PEM POCUS Series: Pediatric Focused Assessment with Sonography for Trauma (FAST)

PEM POCUS fascia iliaca block

Read this tutorial on the use of point of care ultrasonography (POCUS) for Pediatric Focused Assessment with Sonography for Trauma. Then test your skills on the ALiEMU course page to receive your PEM POCUS badge worth 2 hours of ALiEMU course credit.

Take the ALiEMU PEM POCUS: Pediatric FAST Quiz

Module Goals

  1. Summarize the indications and role of the FAST in the evaluation of injured children
  2. Describe the technique for performing the pediatric FAST
  3. Identify anatomical views and landmarks necessary for a complete pediatric FAST
  4. Accurately interpret each pediatric FAST anatomic view and corresponding landmarks
  5. Describe the literature on the pediatric FAST

Case Introduction

You receive an emergency medical services (EMS) notification that they are 2 minutes out from your ED with a 3-year-old boy who fell down a flight of 10 concrete stairs. He is awake and breathing spontaneously but irritable and crying with an obvious deformity to his right arm. EMS placed him in a cervical-collar and are bringing him to your ED.

Vital SignFinding
Temperature37.5oC
Heart Rate158 bpm
Blood Pressure86/48
Respiratory Rate32
Oxygen Saturation98% room air

You conduct your primary assessment:

Trauma AlgorithmAssessment
AirwayPatent: Audibly crying; cervical collar in place
BreathingBilateral breath sounds heard
CirculationSymmetric radial pulses palpable bilaterally; capillary refill 2-3 seconds
DisabilityHis eyes are open, but he is irritable and withdraws to touch (GCS= 13)
ExposureDiffuse superficial abrasions to face and extremities; tenderness and swelling to right forearm; abdomen soft without distension although difficult to appreciate tenderness as patient is crying

You call a trauma consult, connect the patient to the monitor, establish IV access, and reach for your ultrasound probe to perform a FAST.

Trauma remains the leading cause of childhood death and disability in children >1 year of age [1]. While head and thoracic trauma account for most death and disability in children, missed abdominal injuries are a common cause of mortality [2]. Particularly in polytrauma scenarios, it can be difficult for children to locate the exact area of pain and assessing for abdominal injury can be difficult.

FAST is a rapid ultrasound examination of 4 locations (Figure 1) with the primary objective of detecting free fluid within the abdomen, pleural space, and pericardial sac. In injured adults, FAST is useful in rapidly triaging hemodynamically unstable patients to expedite operative management [3]. Free fluid in any one view deems the FAST positive. However, for a FAST to be determined as negative, each of the landmarks in each individual view must be interrogated and evaluated for the presence of free fluid. The role of FAST in the hemodynamically stable child after blunt abdominal trauma is nuanced.

FAST ultrasound probe locations surface anatomy

Figure 1. Location of the 4 FAST views: Right upper quadrant (A), left upper quadrant (B), pelvic (C), subxiphoid (D). Illustration by Dr. Maytal Firnberg.

FAST Technique

The FAST can be performed in parallel with the rest of the trauma evaluation. Serial FAST exams can be repeated as needed throughout the child’s ED stay, particularly if the child has an unexplained change in clinical status. For a complete FAST, each of the views needs to be assessed and every landmark in each view must be visualized. In addition to intra-abdominal hemorrhage and pericardial effusion, point-of-care ultrasound can be used to evaluate the thorax for hemothorax and pneumothorax. When included together, this exam is referred to as the extended FAST (E-FAST).

In general, the child should be positioned supine as free fluid will pool in dependent areas (Figure 2). In children, the recto-vesicular or recto-uterine pouch is the most common place for fluid to collect depending on the patient’s sex [4]. Fluid in the abdomen can move freely up the right pericolic gutter into the right upper quadrant. The left pericolic gutter is higher and the phrenicocolic ligament blocks the flow; consequently, fluid tends to flow to the right pericolic area over the left, regardless of injury type.

Some controversy exists about how much free fluid can be detected by the FAST, and most studies focused on adults. For pediatric patients, we are using 100 mL as it was the median quantity of fluid needed for ultrasound detection of the pelvic view [5].

Free fluid collection areas FAST

Figure 2. Free fluid accumulates in dependent areas. In a supine patient, this is the hepato-renal pouch (right upper quadrant view), the spleno-renal pouch (left upper quadrant view), and recto-vesicular or recto-uterine pouch (pelvic view). Illustration by Dr. Maytal Firnberg.

Use a low frequency ultrasound probe: phased array probe (Figure 3) or curvilinear probe (Figure 4).

    • Phased array probes can generally achieve adequate penetration particularly for smaller pediatric patients and have a smaller footprint allowing for easier intercostal views.
    • Curvilinear probes allow for further penetration and greater depth of abdominal views and may be useful in larger children.

In order to obtain each landmark in the views discussed below, the ultrasound probe will often need to be manipulated in a number of orientations.

probe types

Figure 3 (left): Phased array ultrasound probe; Figure 4 (right): Curvilinear ultrasound probe

For the 4 scanning areas, each view must be interrogated completely, and the clinician should identify all key landmarks. The red dot on the probe correlates with the probe marker.

Right ​​Upper Quadrant (RUQ) View
Probe Placement
RUQ probe placement

Figure 5. Place the probe in the right mid axillary line (around ribs 8-10) with the probe marker towards the head. Fan anterior and posterior and slide up or down a rib space to view the key landmarks.

Normal View and Landmarks
RUQ normal ultrasound view

Figure 6. Normal RUQ ultrasound view with labeled landmarks

  • Diaphragm (including the subdiaphragmatic intraperitoneal space and supradiaphragmatic intrathoracic space)
  • Liver (including the caudal tip of the liver)
  • Kidney (including superior and inferior poles)
  • Hepatorenal Recess (Morison’s Pouch) – A potential space between the liver and kidney where free fluid can collect
Normal Ultrasound Video

Video 1. Normal RUQ ultrasound view
Left ​​Upper Quadrant (LUQ) View
Probe Placement
LUQ probe placement

Figure 7. Place the probe in the left mid or posterior axillary line (around ribs 7-9) with the probe maker towards the head. Fan anterior and posterior and slide up or down a rib space to view the landmarks. In infants and smaller children, the midaxillary line generally provides the best view.

Normal View and Landmarks
Normal LUQ ultrasound view

Figure 8. Normal LUQ ultrasound view with labeled landmarks

  • Diaphragm (including the sub- and supradiaphragmatic areas)
  • Spleen (including splenic tip)
  • Kidney (including superior and inferior poles)
  • Splenorenal Recess – a potential space between the spleen and kidney where free fluid can collect
Normal Ultrasound Video

Video 2. Normal LUQ ultrasound view
Pelvic View
Probe Placement
pelvic probe placement

Figure 9. Place the probe in the midline below the umbilicus and fan or rock the probe down towards the feet until the bladder comes into view. Fan through the entire bladder in both transverse and sagittal orientations. For the transverse and sagittal views, the probe marker should be towards the patient’s right and head, respectively.

Normal View and Landmarks
Normal pelvic ultrasound views

Figure 10. Normal sagittal (left) and transverse (right) views of the pelvic ultrasound with labeled bladder

  • Bladder (including anterior and posterior walls)
    • In patients with uteruses, make sure to visualize the uterus and the recto-uterine space as fluid can collect between the bladder and uterus and also behind the uterus.
Normal Ultrasound Video

Video 3. Normal pelvic ultrasound view (sagittal)

Video 4. Normal pelvic ultrasound view (transverse)
Pericardial View
Probe Placement
pericardial ultrasound probe

Figure 11. Place the probe under the sternum for a subxiphoid view. Point the probe towards the left shoulder and the probe marker towards the right shoulder. This view requires gentle downward pressure as you drop the angle of the probe down towards the patient. If unable to obtain this subxiphoid view, look parasternally.

Normal View and Landmarks
Normal pericardial ultrasound view

Figure 12. Normal pericardial subxiphoid ultrasound view with labeled landmarks

  • Hepatic-pericardial interface
  • Left and right ventricles (atria may also be visible)
  • Pericardial space
Normal Ultrasound Video

Video 5. Normal pericardial ultrasound view (no pericardial effusion and normal contractility)

Free fluid will appear anechoic (black) and will pool in dependent, unobstructed areas. On the right side, fluid in the abdomen can move freely up the pericolic gutter into the right upper quadrant. On the left, the pericolic gutter is higher and the phrenicocolic ligament may impede its flow. The RUQ view is the most sensitive view in adults while the pelvic view is the most sensitive view in children [4]. The following are examples of free fluid identified within the various views of the FAST scan.

free fluid ultrasound labelled

Figure 13. RUQ ultrasound view demonstrating free fluid in Morrison’s pouch in an unlabelled (A) and labelled (B) image

Abnormal RUQ Views

RUQ Free Fluid ultrasound

Figures 14 (left) and 15 (right). Abnormal RUQ ultrasound views with free fluid. Note that the right image demonstrates free fluid both above and below the diaphragm, meaning fluid that is in the peritoneal and pleural cavities, respectively.

Video 6. Abnormal RUQ ultrasound view with free fluid in the pleural space and Morison’s pouch

Abnormal LUQ Views

Tip: In the LUQ view, the free fluid tends to collect just under the diaphragm. Be sure to look at the diaphragm-spleen interface.

LUQ free fluid ultrasound

Figure 16. Abnormal LUQ view with free fluid below the diaphragm and above the spleen

Video 7. Abnormal LUQ ultrasound view with free fluid under the diaphragm

Abnormal Pelvic Views

Tip: Free fluid can collect between the bladder and colon in male patients. In female patients, fluid can collect between the bladder and uterus or between the uterus and colon.

pelvic free fluid ultrasound

Figure 17. Abnormal pelvic view showing free fluid between the bladder and colon

Video 8. Abnormal pelvic ultrasound on sagittal view showing free fluid

Abnormal Pericardial Views

abnormal pericardial FF ultrasound

Figure 18. Abnormal pericardial view showing pericardial free fluid

Video 9. Abnormal pericardial ultrasound view showing free fluid
ArtifactUltrasound Image
Mirror Artifact

These artifacts are cast above the diaphragm in the RUQ and LUQ views.

ultrasound spine sign artifact

Figure 19. The RUQ view shows liver parenchyma architecture cephalad of the diaphragm as a mirror artifact.

Spine Sign

The spine is not typically seen cephalad to the diaphragm by ultrasound due to air artifact. If the spine is visualized above the diaphragm, this indicates the lungs are no longer filled with air, which normally causes the refraction/reflection of ultrasound waves. This occurs in instances where air is replaced by fluid, such as a pleural effusion or hemothorax, or by a dense consolidation or contusion.

Figure 20. A – The spine is not visualized cephalad to the diaphragm in a normal RUQ ultrasound view. B – A pleural effusion results in a “spine sign” where the spine can be seen extended beyond the diaphragm.

Posterior Acoustic Enhancement

Since the bladder is a fluid filled structure which transmits ultrasound waves well, the waves illuminate the posterior wall of the bladder in a phenomenon called posterior acoustic enhancement. This brightness can hide free fluid settled in the pelvis. Thus, decrease the far field gain (brightness) behind the bladder to avoid missing obscured free fluid.

posterior acoustic enhancement

Figure 21. Bladder view with posterior acoustic enhancement artifact

Old Blood

As blood pools, the ultrasound appearance of clotted blood may have similar echotexture to surrounding soft tissue or organs rather than appear anechoic (black) as typical free fluid.

clotted blood artifact

Figure 22. Bladder view showing hypoechoic clotted blood that may be confused as soft tissue

Edge Artifact

Due to ultrasound physics and sound wave transmission between structures of different densities, edge artifacts are seen as a dark thin line tracing off the edge of this interface extending to the bottom of the screen. It can be misinterpreted as free fluid.

edge artifact ultrasound

Figure 23. RUQ view with an edge artifact

Stomach Sabotage

A full stomach will appear as a rounded collection of fluid and air anterior to the spleen. It may mimic a free fluid collection. Fan posterior of the stomach to visualize the spleen and perisplenic spaces.

Stomach sabotage artifact

Figure 24. The stomach obscures the LUQ view. Note the mix of bright (air) and dark (other gastric contents) inside the stomach.

Seminal Vesicles

Seminal vesicles can appear as hypoechoic, contained, symmetric structures posterior to the bladder in the transverse view and can be mistaken for free fluid.

Seminal vesicle artifact

Figure 25. Bladder view showing hypoechoic seminal vesicles  posterior to the bladder

  • The FAST evaluates for the presence free fluid only [6].
    • In trauma, the assumption is that free fluid is due to hemorrhage; however, the FAST cannot adequately distinguish between blood and other types of free fluid, such as ascites or physiologic free fluid.
    • It does not directly evaluate for injury to solid organs, bowel, diaphragm, or retroperitoneum​.
  • In isolation, the FAST cannot rule out intra-abdominal injury [7].
  • The FAST can not detect tiny amounts of hemorrhage.
    • The scan may appear initially negative with a free fluid volume under a threshold of about 100 mL [5].
    • Repeat FAST scans may help detect an accumulation of fluid over time throughout a child’s evaluation.
  • Trace pelvic free fluid may be physiologic in children, thus limiting specificity [8].

For adults, the FAST is integral in the diagnostic evaluation after blunt and penetrating trauma [9]. It improves outcomesby decreasing the time to surgical intervention, patient length of stay, surgical complications, CT scan, and diagnostic peritoneal lavage rates [3].

For children, however, the literature is less clear cut. Pediatric injury patterns commonly result in solid organ lacerations without hemoperitoneum, making the FAST a less sensitive means for detecting important intra-abdominal injury [7]. Further, the test characteristics of the FAST have variable reliability and accuracy in children [7,10,11]. This variation contributes to uncertainty of how to use results of the FAST and decreases its impact on potentially important clinical outcomes such as rates of CT scans and ED length of stay [12]. However…

  • The FAST is able to identify injuries that the physical exam can miss. When combined with the physical exam, the FAST scan has been found to have better test characteristics than the physical exam alone [13].
  • The improvement in POCUS technology, widespread pediatric-specific POCUS expertise, and a focus on clinically relevant outcomes have allowed clinicians to integrate the FAST into novel diagnostic strategies for children after blunt torso trauma [14].
  • The pediatric FAST may be used in combination with signs, symptoms, and other diagnostic testing as a screening algorithm to decrease unnecessary CTs. Investigators will need to conduct larger validation trials to confirm and clarify the algorithm.

Studies that have shaped the pediatric FAST literature landscape:

StudyStudy Type, Location (Time Frame)N, AgesNotes
Menaker et al., J Trauma Acute Care Surg 2014 [7]

Secondary Analysis of a Prospective Observational Study

Multicenter (May 2007 to January 2010)

6,468

Median age, 11.8 yrs; interquartile range (IQR) 6.3-15.5 yrs

  • Evaluated the variability of clinician-performed FAST examinations and the use of abdominal CT following FAST examination in children with blunt trauma
  • 373 (5.8%) were diagnosed with intra-abdominal injury
  • 3,015 (46.6%) underwent abdominal CT scanning. Only 887 (13.7%) underwent FAST examination before CT scan.
  • Use of the FAST increased as clinician suspicion for intra-abdominal injury increased. When clinicians had a lower suspicion, they were significantly less likely to order a CT scan, if a FAST examination was performed.
Holmes et al., JAMA 2017 [12]

Randomized Clinical Trial

University of California, Davis Medical Center (April 2012-May 2015)

925

Mean 9.7 yrs; SD 5.3 yrs

  • Studied the impact of the FAST scan on on multiple patient centered outcomes
  • Hemodynamically stable patients with blunt torso trauma were randomized a FAST or no FAST scan.
  • 50 had intra-abdominal injury, including 40 patients (80%) with intraperitoneal fluid and 9 patients underwent laparotomy.
  • No difference in the proportion obtaining CT, missed intra-abdominal injuries, length of stay, or cost.
Kornblith et al., Acad Emerg Med 2020 [13]

Retrospective Review

University of California, Benioff Children’s Hospital Oakland (November 2013 to July 2015)

354

Median age 8 yr; IQR 4-12 yr

  • Query of trauma database for children who met institutional trauma activation criteria and who also had a FAST performed.
  • 50 (14%) patients were found to have an intra-abdominal injury with 13 (4%) requiring intervention.
  • Positive FAST and positive physical exam were found to be independent predictors of intra-abdominal injury, both with a 74% sensitivity.
  • When combined, FAST and physical exam (FAST-enhanced physical exam) improved sensitivity to 88% (NPV 97.3%).
Liang et al., Pediatr. Emerg Care 2021 [11]

Systematic Review and Meta-Analysis

Multicenter (January 1966- March 2018)

2,135

Study dependent

  • Based on 8 studies, the FAST had a pooled sensitivity of 35% and specificity 96% for intra-abdomianal injury.
  • All 8 studies were prospective; 1 of the 8 was the 2017 Holmes paper mentioned above [12].
  • Conclusion: For a positive FAST, the post-test probability of an intra-abdominal injury was 63% meaning that those patients should get a CT to characterize injury. If the FAST is negative, you may still need a CT, because the post-test probability of intra-abdominal injury was still relatively high at 9%.
  • None of the studies had low enough negative likelihood ratios to obviate the need for CT.
  • Although a negative FAST alone does not exclude an intra-abdominal injury, it can identify low-risk patients with a reassuring physical exam and GCS 14-15.
Kornblith et al., JAMA 2022 [15]

Expert, consensus–based Modified Delphi

International multicenter (May 2021 to June 2021)

n/a
  • Generated definitions for complete pediatric FAST and E-FAST studies in the context of blunt trauma

Future Directions

The use of FAST in pediatric trauma is an evolving area of active research. A clear consensus on the way the FAST fits into pediatric trauma protocols is yet to be determined. Studies will need to be performed to examine the benefits of serial FAST, patient factors that may influence its test characteristics, and effect on patient centered outcomes.

There are a number of strategies to incorporate the above studies into clinical care, and one example is illustrated in the algorithm below. Keep in mind that FAST should be used in conjunction with other signs and symptoms of intra-abdominal injury (vomiting, decrease breath sounds, abdominal pain, thoracic wall trauma). Also consider laboratory testing such as liver function tests and urinalysis, depending on the clinical context and consulting your surgical colleagues.

Sample Algorithm for Pediatric Blunt Torso Trauma

Zuckerberg San Francisco General Pediatric Blunt Torso Trauma Algorithm (shared with permission)

Case Resolution

The primary survey is completed with airway, breathing, and circulation noted to be intact. As someone starts the secondary survey, you grab a phased array probe and perform a FAST . You observe the following:

RUQ View

LUQ View

Pelvis View, Sagittal

Pelvis View, Transverse

Pericardial View

You call out ‘FAST negative’ to the documenting nurse and team leader.

ED Course

The patient has radiographs performed of his chest, pelvis, neck, and right forearm. He is diagnosed with a type 3 supracondylar humeral fracture but the other radiographs are negative for fracture and pneumothorax. The rest of his evaluation is reassuring. Orthopedics is consulted and they admit him for surgery. He is discharged home the next day with pediatrician follow up.

Pediatrician Clinic Follow-Up

At her pediatrician clinic visit 1 week later, he is playful and active with his arm in a cast. He has been eating and drinking normally without any complaints of abdominal pain. He has orthopedics follow up scheduled for the following week.

Learn More…

References

  1. Leading Causes of Death by Age Group United States 2018. Centers for Disease Control and Prevention. Accessed September 28, 2022
  2. Kenefake ME, Swarm M, Walthall J. Nuances in Pediatric Trauma. Emerg Med Clin North Am. 2013;31(3):627-652. doi:10.1016/j.emc.2013.04.004
  3. Melniker LA, Leibner E, McKenney MG, Lopez P, Briggs WM, Mancuso CA. Randomized controlled clinical trial of point-of-care, limited ultrasonography for trauma in the emergency department: the first sonography outcomes assessment program trial. Ann Emerg Med. 2006;48(3):227-235. doi:10.1016/j.annemergmed.2006.01.008
  4. Brenkert TE, Adams C, Vieira RL, Rempell RG. Peritoneal fluid localization on FAST examination in the pediatric trauma patient. Am J Emerg Med. 2017;35(10):1497-1499. doi:10.1016/j.ajem.2017.04.025
  5. Jehle DVK, Stiller G, Wagner D. Sensitivity in Detecting Free Intraperitoneal Fluid With the Pelvic Views of the FAST Exam.
  6. Netherton S, Milenkovic V, Taylor M, Davis PJ. Diagnostic accuracy of eFAST in the trauma patient: a systematic review and meta-analysis. CJEM. 2019;21(6):727-738. doi:10.1017/cem.2019.381
  7. Menaker J, Blumberg S, Wisner DH, et al. Use of the focused assessment with sonography for trauma (FAST) examination and its impact on abdominal computed tomography use in hemodynamically stable children with blunt torso trauma. J Trauma Acute Care Surg. 2014;77(3):427-432. doi:10.1097/TA.0000000000000296
  8. Berona K, Kang T, Rose E. Pelvic Free Fluid in Asymptomatic Pediatric Blunt Abdominal Trauma Patients: A Case Series and Review of the Literature. J Emerg Med. 2016;50(5):753-758. doi:10.1016/j.jemermed.2016.01.003
  9. Bloom BA, Gibbons RC. Focused Assessment with Sonography for Trauma. In: StatPearls. StatPearls Publishing; 2021. Accessed November 14, 2021.
  10. Holmes JF, Gladman A, Chang CH. Performance of abdominal ultrasonography in pediatric blunt trauma patients: a meta-analysis. J Pediatr Surg. 2007;42(9):1588-1594. doi:10.1016/j.jpedsurg.2007.04.023
  11. Liang T, Roseman E, Gao M, Sinert R. The Utility of the Focused Assessment With Sonography in Trauma Examination in Pediatric Blunt Abdominal Trauma: A Systematic Review and Meta-Analysis. Pediatr Emerg Care. 2021;37(2):108-118. doi:10.1097/PEC.0000000000001755
  12. Holmes JF, Kelley KM, Wootton-Gorges SL, et al. Effect of Abdominal Ultrasound on Clinical Care, Outcomes, and Resource Use Among Children With Blunt Torso Trauma: A Randomized Clinical Trial. JAMA. 2017;317(22):2290-2296. doi:10.1001/jama.2017.6322
  13. Kornblith AE, Graf J, Addo N, et al. The Utility of Focused Assessment With Sonography for Trauma Enhanced Physical Examination in Children With Blunt Torso Trauma. Acad Emerg Med Off J Soc Acad Emerg Med. 2020;27(9):866-875. doi:10.1111/acem.13959
  14. Riera A, Hayward H, Torres Silva C, Chen L. Reevaluation of FAST Sensitivity in Pediatric Blunt Abdominal Trauma Patients: Should We Redefine the Qualitative Threshold for Significant Hemoperitoneum? Pediatr Emerg Care. 2021;37(12):e1012. doi:10.1097/PEC.0000000000001877
  15. Kornblith AE, Addo N, Plasencia M, et al. Development of a Consensus-Based Definition of Focused Assessment With Sonography for Trauma in Children. JAMA Netw Open. 2022;5(3):e222922. Published 2022 Mar 1. doi:10.1001/jamanetworkopen.2022.2922

IDEA Series: Ultrasound-capable, 3D-printed central line trainer

Problem: Central venous line (CVL) placement is a key skill for emergency medicine providers. Sites for central line placement include the internal jugular vein, subclavian vein, and femoral vein. Indications include, but are not limited to fluid resuscitation, medication administration, central venous pressure monitoring, pulmonary artery catheter introduction, and transvenous pacing wire placement. Procedural complications can include catheter-associated infection and arterial puncture. Success rates for CVL placement vary based on location and provider experience [1-3]. Point-of-Care Ultrasound (POCUS) increases both success rate and patient safety when used to guide CVL placement [4].

central line trainer 3d idea

Figure 1. Setup for ultrasound-capable, 3D-printed central line trainer

The Innovation

The ultrasound-capable, 3D-printed central line trainer was created to facilitate realistic training of POCUS-guided CVL placement, specifically utilizing the internal jugular vein. The trainer uses a ballistic gel insert that is ultrasound-capable and replaceable, as needed.

The Learners

The model can be utilized by anyone needing practice and training on central line placement. This includes medical and physician assistant students, residents, and fellows. It will be particularly useful with students familiar with POCUS basics.

Group Size

In our experience, 4-5 students were able to utilize the model before the wear from repeated use began to impact the imaging and structure of the model, necessitating replacement of the insert. The dilation step of the Seldinger technique can be skipped or simulated in order to prolong the life of the gel insert.

Equipment

Description of the Innovation

  • The initial head model was designed using 2 common 3D modeling software systems: Tinkercad and  Meshmixer
  • A generic head and neck model was imported into Meshmixer. Using the available tools in Meshmixer, the head was rotated to the side and the neck was manipulated to enhance the appearance of an extended neck with close attention to the sternocleidomastoid muscle and clavicle.
  • The model was then imported into Tinkercad and a section of the neck was removed, inverted, and manipulated inside of a box to create a negative (mold).

central line trainer tinkercad

Figure 2. Screenshot of head being edited in Tinkercad software

central line trainer tinkercad neck

Figure 3. Screenshot of neck mold being edited in Tinkercad software

  • The head was printed with Polylactic acid (PLA) filament in 2 sections that were then glued together with superglue. The seam was sealed and smoothed with latex caulk. The files for both the head and the mold can be found in this Google Drive folder.
  • A hole was drilled from the base of the neck through the top of the head. A second hole was drilled in the base of the model.
  • To make a suitable tray for the ballistic gel insert, a thin plate was printed and then cut to fit the shape of the neck. Finally, that piece was glued to the bottom of the model.
  • The model was painted using matte spray paint.

central line trainer spray paint

Figure 4. Use of matte spray paint to paint the model

  • The mold was printed next. Two holes were drilled on either side to allow for insertion of latex tubing.
  • The ballistic gel was heated according to the directions on the box. The gel can be colored using dye or acrylic paint. Caution should be practiced when using acrylic paint. The heated gel can foam up, increasing the possibility of injury from burn.
  • While the gel was heating, the mold was prepared. The bottom was coated with a thin layer of dish soap to assist with gel release. Two sections of latex tubing, approximately 2 feet each were inserted into the mold. Modeling clay was used to fill the gaps.
  • Once colored and thoroughly heated, the gel was poured into the mold.

central line trainer mold internal jugular vein

Figure 5. Preparation of the mold in which the heated gel will be poured

central line trainer mold pour

Figure 6. The heated, colored gel is poured into the mold

  • After curing, the latex tubes were removed. The gel neck model was then removed and placed into the accompanying space on the 3d printed trainer.
  • The latex tubing was fished back through the available holes, and filled with water. As an optional step, a 30 cc syringe was attached to one end of the thicker tube. Tube stoppers can also be printed and used in place of hemostats. Pumping the syringe plunger simulates the appearance of arterial flow on ultrasound.

Video Demonstration of Final Product

Lessons learned

We are currently investigating how best to research this model. The model is inexpensive compared to available commercial CVL trainers. We estimate the cost at approximately $80 per model in materials. This, of course, does not include the price of a 3d printer, 18v drill, or drill bit. Two comparable models available for purchase are both listed for over $1000 [5, 6]. The build time is approximately 1 week with time spent printing, glue-drying, and ballistic gel setting. The model can be used repeatedly and the insert remade many times over.

If another model were to be designed, the top of the head could be sacrificed in favor of an elongated neck section. The top of the head provides no value and consumes 3d printing filament. Furthermore, an elongated neck may be preferable for a new learner by allowing more room to practice probe and hand placement.

Theory behind the innovation

Simulation as a means of teaching has been a firmly established practice across the landscape of medical education. The model in question is high-fidelity and offers the user a realistic experience in a low-stress environment. The model is small enough to be portable and can be used with little preparation, making it an ideal tool for just-in-time training in the emergency department.

Tools that allow the learner to practice multiple steps of a skill during one exercise are invaluable for skill development, competency-based medical education and mastery learning.

References

  1. McGee DC, Gould MK. Preventing complications of central venous catheterization. New England Journal of Medicine. 2003;348(12):1123-1133. doi:10.1056/nejmra011883
  2. Schummer W, Köditz JA, Schelenz C, Reinhart K, Sakka SG. Pre-procedure ultrasound increases the success and safety of central venous catheterization. British Journal of Anaesthesia. 2014;113(1):122-129. doi:10.1093/bja/aeu049
  3. E Portalatin M, Fakhoury E, Brancato R, et al. Factors contributing to unsuccessful central line placement in the neck and chest. Surgery: Current Trends and Innovations. 2019;3(2):1-5. doi:10.24966/scti-7284/100015
  4. Saugel B, Scheeren TWL, Teboul J-L. Ultrasound-guided central venous catheter placement: A Structured Review and recommendations for Clinical Practice – Critical Care. BioMed Central. Published August 28, 2017. Accessed September 21, 2022.
  5. Life/form Central Venous Cannulation Simulator. Universal Medical. . Accessed September 21, 2022.
  6. Blue Phantom internal jugular Central Line Ultrasound manikin. 3012495 – Blue Phantom – BPP-060 – Ultrasound Trainers. Accessed September 21, 2022.

Trick of the Trade: Getting the last bit of ultrasound gel from the bottle

It’s a busy shift and you need to perform a bedside ultrasound on a patient’s belly to rule out cholecystitis, when you realize that the ultrasound gel bottle is nearly empty. No matter how many times you vigorously shake the bottle, it’s impossible to get the viscous gel out. In a pinch, you could use hand sanitizer, sterile lubricant, or even water as a substitute for gel. Or you could run to the storage room on the other side of the busy department to grab a new bottle. Or…

Trick of the Trade

Use centrifugal force to move the gel to the top of the bottle!

trick ultrasound bottle gel out


  • Turn the bottle upside down so the cap is facing the ground.
  • Place the bottle into a (fresh) patient’s sock or transducer cover. Alternatively, you can use a plastic bag or ortho tubular stockinette.
  • Firmly holding the bag, and spin the bag for a few seconds in a circular motion, almost like you were throwing a grappling hook.
  • The centrifugal motion will generate an outward force pushing all of the viscous gel to the bottle cap!
  • Once you’ve used the gel, store the bottle cap-side down so you don’t have to do this again.

This trick is useful in a pinch, because it makes use of the entire gel bottle and promotes an eco-friendly use of ED resources.

Tip: Just don’t let go while you swing, lest you turn that patient with the belly pain into a trauma activation from a bottle to the face.

Interest in other tricks?

Read more articles in the Tricks of the Trade series.

By |2022-07-25T11:26:09-07:00Jul 27, 2022|Tricks of the Trade, Ultrasound|

Trick of the Trade: Don’t fight the ultrasound cord for peripheral IV access

ultrasound POCUS peripheral iv trick

Ultrasound-guided IVs require hand-eye coordination and fine movements of probe in Goldilocks fashion. Apply too much pressure, and the vein in question is compressed. Slide a little to the right, and now it’s out of the window. Something that practitioners don’t think about is the tension from the cord. If left to its own devices, the cord will tug on the probe, making the probe harder to steer and handle, especially for those tiny veins.

Trick of the Trade: Reduce cord tension

Have the patient grasp the cord!

This makes them an active participant. Usually, if they are awake and good-humored, tell them “audience participation is required.” Doing so will give you enough slack to effectively visualize and troubleshoot the ultrasound-guided IV.

ultrasound cord trick POCUS

 

What if the patient is intubated, or altered, doesn’t quite grasp, or can’t handle the situation?

Tape the cord to the gurney side rail. Use a 2×2 gauze as a buffer between the tape and the rail so the tape doesn’t damage the cord itself.

ultrasound cord POCUS tape

 

Want to learn other tricks?

Read other articles in the Tricks of the Trade series.

By |2022-05-31T00:37:48-07:00Jun 3, 2022|Tricks of the Trade, Ultrasound|

PEM POCUS Series: Pediatric Appendicitis

PEM POCUS pediatric appendicitis

Read this tutorial on the use of point of care ultrasonography (POCUS) for pediatric appendicitis. Then test your skills on the ALiEMU course page to receive your PEM POCUS badge worth 2 hours of ALiEMU course credit.

Take the ALiEMU PEM POCUS: Pediatric Appendicitis Quiz

Module Goals

  1. Describe the indications for performing point-of-care ultrasound (POCUS) for appendicitis
  2. Describe the technique for performing POCUS for appendicitis
  3. Recognize anatomical landmarks for POCUS for appendicitis
  4. Interpret signs of appendicitis on POCUS
  5. List the limitations of POCUS for appendicitis

Case Introduction: Child with thigh pain

Mason is an 8-year-old boy who comes to the emergency department for abdominal pain. The pain has been present for 12 hours, started near his belly button, and now has migrated to the lower right side. He describes it as constant and worsening. His parents are concerned because he had a fever to 101F since 2 hours prior to arrival and had 2 episodes of emesis. They deny diarrhea or bloody stool. They gave acetaminophen for fever 2 hours prior to arrival. He has not wanted to eat anything today.

Vital SignFinding
Temperature37.5 C
Heart Rate120 bpm
Blood Pressure106/58
Respiratory Rate18
Oxygen Saturation (room air)100%

He is uncomfortable appearing, and abdominal examination is soft and tender to palpation periumbilically and in the right lower quadrant. The patient also endorses pain with jumping. Given his history and abdominal pain and tenderness on examination, you are concerned for appendicitis. You place a surgical consult and while waiting, decide to perform a point of care ultrasound (POCUS) examination of the appendix.

Why should I perform the appendix POCUS?

  • Lack of radiation exposure, lower cost, less patient preparation
  • Superior sensitivity and specificity for diagnosing pediatric appendicitis
  • POCUS can save ≥2 hours compared to radiology-performed ultrasound
  • Can help prioritize radiology studies or expedite surgical consult

Limitations of the appendix POCUS

  • Operator dependency and variability in sensitivity
  • Difficult visualization of appendix in retrocecal or aberrant locations
  • Limitation of visualization dependent on patient body habitus
  • Sometimes the appendix cannot be visualized (normal or otherwise)

What are the general principles behind the technique?

  • You are using POCUS to look for an abnormal appendix and/or secondary signs of appendicitis.
  • It is important to recognize anatomical landmarks.
  • The patient should be placed in a supine position.
  • Using the linear transducer is appropriate for most pediatric patients, but if the patient has a larger body habitus, the curvilinear transducer may be used (figure 1).

Figure 1. Linear (left) and curvilinear (right) transducer for ultrasonography

  • Place the probe over the point of maximal tenderness in the abdominal RLQ.
  • Slowly apply increasing gentle pressure (i.e., “graded compression”) to move bowel gas out of the way until able to identify the important landmarks:
    • Iliopsoas muscle
    • Rectus muscle
    • Iliac vessels
  • You can also lightly “jiggle” the probe as shown below to help mitigate bowel gas artifact.
Video 1: External view of the RLQ abdomen with the application of graded compression, such that bowel gas is moved out of the way to obtain a view of the desired anatomical structures
Video 2: POCUS clip of the RLQ abdomen demonstrating the application of graded compression and “jiggling” the probe

1. Start in the RLQ Abdomen

appendicitis pediatric abdomen

Figure 2: Starting in the RLQ abdomen and inferior to the iliac crest, visualize the iliacus muscle and pelvis with no bowel in view. The first bowel you visualize should be the cecum as you scan in a cephalad direction.

Video 3: POCUS clip of the RLQ abdomen showing the cecum coming into view

2. Move the probe more cephalad

Figure 3: Moving the probe in a progressively more cephalad direction, attempt to visualize the iliopsoas, abdominis rectus muscles, and iliac vessels. These anatomic landmarks to help identify the appendix (marked as *) with the CURVILINEAR probe. The appendix may appear in the triangle made by these structures as a blind-ended pouch that does not have peristalsis.[Image courtesy of Dr. Sally Graglia]

Figure 4: Anatomic landmarks to help identify the appendix with the LINEAR probe [image courtesy of Dr. Sally Graglia]


3. Identify the tubular appendix structure

Figure 5: Visualize the appendix in the longitudinal view. In this plane, visualize the end of the pouch to confirm it is a blind-ending tubular structure with no peristalsis that initiates at the cecum. [Image courtesy of Dr. Margaret Martore-Lin]

Figure 6: Visualize the appendix in the transverse view. In this plane, measure the diameter of the appendix from the outer wall to outer wall. An abnormal appendix is >6 mm and non-compressible. [Image courtesy of Dr. Margaret Martore-Lin]

A technique described in Sivitz et al. [1] involves placing the ultrasound probe in a transverse position and starting at the level of the umbilicus. Using compression, move the probe along POCUS-identified anatomical landmarks.

  1. Move laterally to identify the lateral border of the ascending colon.
  2. Move down the lateral border to the end of the cecum.
  3. Move medially across the psoas and iliac vessels.
  4. Move down the border of the cecum.
  5. Move up the border of the cecum.
  6. Rotate the probe into a sagittal position and identify the end of the cecum in the long axis and move medially across the psoas.

Figure 7: The Sivitz et al technique for identifying the appendix on POCUS

Sometimes there is a suboptimal view of the anatomy landmarks on POCUS. The following are troubleshooting tips that may be useful:

  1. Perform graded compression to displace bowel gas that may be obscuring your view.
  2. Apply posterior manual compression to the right lower back in an anteromedial direction of the ultrasound probe. This is usually done with the POCUS operator’s opposite hand (Figure 7).
pediatric appendicitis POCUS posterior compression

Figure 8: Posterior manual compression technique to assist with POCUS visualization of the appendix

  1. Position the patient in the left lateral decubitus position to help visualization of a retrocecal appendix.
  2. Administer analgesia before starting and distraction (videos, smartphone) during the exam to reduce patient movement.
  3. Position the patient with knees flexed, which can relax the abdominal wall musculature.
  4. Use a high-frequency linear probe to improve the resolution of regional structures and anatomy (although a curvilinear probe should be used if increased depth is required for a larger body habitus).
pediatric normal appendix POCUS

Figure 9: Normal appearing appendix on POCUS [Image courtesy of Dr. Will Shyy]

The appendix is a tubular, blind ending structure, which initiates from the cecum and has no peristalsis. A normal appendix is less than 6 mm, is compressible, and has little to no blood flow in the wall of the appendix.

Ultrasonography Signs of Acute Appendicitis

  1. Enlarged appendix >6 mm (Figure 10)
  2. Noncompressible (although can be compressible if perforated appendix)
pediatric appendicitis POCUS

Figure 10: Enlarged appendix measuring 1.36 cm (>6 mm is abnormal) with hyperechoic fat concerning for inflammation [Image courtesy of Dr. Will Shyy]

Secondary Ultrasonographic Signs of Appendicitis

  1. Peri-appendiceal free fluid
  2. Hyperechoic mesenteric fat
  3. Appendicolith
  4. Increased blood flow (“ring of fire”) surrounding the appendix on Doppler color mode
  5. Complex right lower quadrant mass, suggestive of ruptured appendix
Secondary Sign of AppendicitisUltrasound View
Peri-appendiceal free fluid secondary to inflammatory edema or perforation. You may also see an abscess that appears as a complex mass and is a sign of a ruptured appendicitis.
pediatric appendicitis POCUS

Figure 11. Appendix with peri-appendiceal fluid collection [image by Dr. Will Shyy]

Hyperechoic mesenteric fat as a sign of inflammation visible (also see figure 10)
pediatric appendicitis POCUS

Figure 12: Appendicolith (A) within the lumen of the appendix in addition to hyperechoic fat (arrows) concerning for inflammation [image courtesy of Dr. Will Shyy]

pediatric appendicitis POCUS

Figure 13. Appendicitis with hyperechoic fat suggestive of inflammation

Video 4: POCUS clip of a pediatric patient with appendicitis. Notice the hyperechoic fat surrounding the appendix, visible in transverse as a tubular structure at the bottom of the screen.
Appendicolith: A hyperechoic structure within the appendiceal lumen has a dark, clean acoustic shadow, similar to the appearance of a gallstone.Figure 12 above
“Ring of Fire”, or increased blood flow surrounding the appendix: Using the color Doppler mode on the ultrasound, the appendix in transverse view will appear hyperemic, suggestive of appendiceal inflammation.
pediatric appendicitis POCUS ring of fire

Figure 14. “Ring of fire” appendiceal hyperemia using the color Doppler mode on ultrasound [image by Dr. Will Shyy]

pediatric appendicitis POCUS

Figure 15. Cross-sectional image of appendicitis with hyperemia

Complex RLQ mass: A ruptured appendicitis may appear as a complex right lower quadrant mass, where the appendix itself may be difficult to visualize. It can be difficult to distinguish this from other pathologies, such as intussusception or ruptured Meckel’s diverticulitis.

Video 5: POCUS clip of ruptured appendicitis, appearing as a complex right lower quadrant mass
pediatric appendicitis POCUS

Figure 16. Close-up POCUS view of the appendix from video 5

Benefits of Appendix POCUS

An appendix POCUS benefits children with suspected appendicitis, as demonstrated in the literature:

  1. Decrease in CT scan utilization [2-4]
  2. Decrease in lengths of Emergency Department stay [3, 4]
    • Tsung et al, Critical Ultrasound J, 2014 [4]: There was a shorter ED length of stay (LOS) with mean LOS reported for the following modalities:
      • POCUS: 154 minutes
      • Radiology US: 288 minutes
      • CT scan: 487 minutes

Equivocal Findings on POCUS

  • Oftentimes an appendix cannot be visualized on both POCUS and radiology-performed ultrasound, especially in patients with higher BMI [5].
  • In situations with an experienced sonographer, where the appendix is not visualized and there are no secondary signs on radiology-performed ultrasound, patients are at low risk for appendicitis with a negative predictive value in the 80’s% [6, 7].
  • Serial ultrasound has been recommended in equivocal ultrasound cases as ultrasound’s sensitivity increases with length of pain [8].
  • For POCUS for appendicitis, non-visualized appendix studies continue to represent a diagnostic dilemma [1, 9]. For more on this topic, read a deeper-dive on this topic in a PEM Pearls post.

The studies below examine the sensitivity and specificity of appendix POCUS for identification of appendicitis in patients of any age with the exception of Sivitz et al., which specifically studied pediatric patients only. (Table 1).

StudyNPatient AgeSensitivitySpecificityComments
Sivitz et al., 2014 [1]264Pediatric
85%
(95% CI: 75-95%)
93%
(95% CI: 85-100%)
In this study, pediatric emergency medicine ultrasonographers were able to visualize the appendix in 71% of patients. Gold standard was either pathologic review, telephone follow-up to 6 months, or electronic medical records review up to 1 year, if unable to reach the patient.
Fields et al., 2017 [9]6,636Pediatric89%

(95% CI: 47–99%)

97%

(95% CI: 84–99%)

These test characteristics were derived from a pediatric-only sub-analysis of a larger systematic review and meta‐analysis study across all ages to identify the test characteristics of the appendix POCUS, performed by emergency physicians. The overall test characteristics across all ages was 91%
(95% CI: 83–96%) sensitivity and 97% (95% CI: 91–99%) specificity.
Chen et al., 2000 [10]317Any age85%98%After a 5-day intensive training course in abdominal ultrasound, emergency physician-performed POCUS was compared to surgeon’s clinical impression in diagnosing acute appendicitis, as confirmed by pathological reports. Ultrasonography performed better than surgeon clinical impression and resulted in a high sensitivity and specificity.
Fox et al., 2008 [11]132Any age65%

(95% CI: 52-76%)

90%

(95% CI: 81-95)

Emergency physicians performed a 5-minute appendix POCUS for patients with a clinical suspicion for acute appendicitis. The gold standard confirmation was either pathology specimens from appendectomy surgery or telephone follow-up.
Table 1. Published studies evaluating the sensitivity and specificity of appendix POCUS

Case Resolution

The patient has a leukocytosis with a WBC 13.3 x 109/L and an absolute neutrophils count (ANC) 10.3 x 109/L but otherwise unremarkable labs. His final Pediatric Appendicitis Score (PAS) is 8. You decide to incorporate appendix POCUS to your evaluation. You place a linear, high-frequency transducer on the patient and visualize his appendix. You observe the following:

Video 6. An appendix POCUS, demonstrating appendicitis.

Figure 17: Enlarged appendix measuring 1.36 cm in diameter (>6 mm is abnormal)

Normal anatomy for comparison:

Video 7: Appendix POCUS clip showing normal anatomy including the psoas muscle, vasculature, and a small, compressible appendix.

ED Course

The patient receives IV morphine and is made NPO. The general surgeon on call is consulted and agrees with the plan for an appendectomy.


Learn More…

References

  1. Sivitz AB, Cohen SG, Tejani C. Evaluation of acute appendicitis by pediatric emergency physician sonography. Ann Emerg Med. 2014;64(4):358-364.e4. doi:10.1016/j.annemergmed.2014.03.028. PMID: 24882665
  2. Doniger SJ, Kornblith A. Point-of-Care Ultrasound Integrated Into a Staged Diagnostic Algorithm for Pediatric Appendicitis. Pediatr Emerg Care. 2018;34(2):109-115. doi:10.1097/PEC.0000000000000773. PMID: 27299296
  3. Elikashvili I, Tay ET, Tsung JW. The effect of point-of-care ultrasonography on emergency department length of stay and computed tomography utilization in children with suspected appendicitis. Acad Emerg Med. 2014;21(2):163-170. doi:10.1111/acem.12319. PMID: 24673672
  4. Tsung JW, Tay ET, Elikashvili I.  The effect of point-of-care ultrasonography on emergency department length of stay and CT utilization in children with suspected appendicitis. rit Ultrasound J 6, A32 (2014). https://doi.org/10.1186/2036-7902-6-S1-A32
  5. Abo A, Shannon M, Taylor G, Bachur R. The influence of body mass index on the accuracy of ultrasound and computed tomography in diagnosing appendicitis in children. Pediatr Emerg Care. 2011;27(8):731-736. doi:10.1097/PEC.0b013e318226c8b0. PMID: 21811194
  6. Cohen B, Bowling J, Midulla P, et al. The non-diagnostic ultrasound in appendicitis: is a non-visualized appendix the same as a negative study?. J Pediatr Surg. 2015;50(6):923-927. doi:10.1016/j.jpedsurg.2015.03.012. PMID: 25841283
  7. Ly DL, Khalili K, Gray S, Atri M, Hanbidge A, Thipphavong S. When the Appendix Is Not Seen on Ultrasound for Right Lower Quadrant Pain: Does the Interpretation of Emergency Department Physicians Correlate With Diagnostic Performance?. Ultrasound Q. 2016;32(3):290-295. doi:10.1097/RUQ.0000000000000214. PMID: 27082937
  8. Bachur RG, Dayan PS, Bajaj L, et al. The effect of abdominal pain duration on the accuracy of diagnostic imaging for pediatric appendicitis. Ann Emerg Med. 2012;60(5):582-590.e3. doi:10.1016/j.annemergmed.2012.05.034. PMID: 22841176
  9. Matthew Fields J, Davis J, Alsup C, et al. Accuracy of Point-of-care Ultrasonography for Diagnosing Acute Appendicitis: A Systematic Review and Meta-analysis. Acad Emerg Med. 2017;24(9):1124-1136. doi:10.1111/acem.13212. PMID: 2846445
  10. Chen SC, Wang HP, Hsu HY, Huang PM, Lin FY. Accuracy of ED sonography in the diagnosis of acute appendicitis. Am J Emerg Med. 2000;18(4):449-452. doi:10.1053/ajem.2000.7343. PMID: 10919537
  11. Fox JC, Solley M, Anderson CL, Zlidenny A, Lahham S, Maasumi K. Prospective evaluation of emergency physician performed bedside ultrasound to detect acute appendicitis. Eur J Emerg Med. 2008;15(2):80-85. doi:10.1097/MEJ.0b013e328270361a. PMID: 18446069

Additional Reading

  1. Benabbas R, Hanna M, Shah J, Sinert R. Diagnostic Accuracy of History, Physical Examination, Laboratory Tests, and Point-of-care Ultrasound for Pediatric Acute Appendicitis in the Emergency Department: A Systematic Review and Meta-analysis. Acad Emerg Med. 2017;24(5):523-551. doi:10.1111/acem.13181. PMID: 28214369
  2. Estey A, Poonai N, Lim R. Appendix not seen: the predictive value of secondary inflammatory sonographic signs. Pediatr Emerg Care. 2013;29(4):435-439. doi:10.1097/PEC.0b013e318289e8d5. PMID: 23528502Lin-Martore M, Kornblith AE. Diagnostic Applications of Point-of-Care Ultrasound in Pediatric Emergency Medicine. Emerg Med Clin North Am. 2021 Aug;39(3):509-527. doi: 10.1016/j.emc.2021.04.005. PMID: 34215400
  3. Vasavada P. Ultrasound evaluation of acute abdominal emergencies in infants and children. Radiol Clin North Am. 2004;42(2):445-456. doi:10.1016/j.rcl.2004.01.003. PMID: 15136027
By |2022-06-01T10:15:33-07:00May 31, 2022|Pediatrics, PEM POCUS, Ultrasound|

PEM POCUS Series: Confirmation of Endotracheal Tube Placement

PEM POCUS endotracheal tube confirmation badge

Read this tutorial on the use of point of care ultrasonography (POCUS) for confirmation of endotracheal tube (ETT) placement in pediatric patients. Then test your skills on the ALiEMU course page to receive your PEM POCUS badge worth 2 hours of ALiEMU course credit.

Take the ALiEMU PEM POCUS: Pediatric ETT Confirmation Quiz

Module Goals

  1. List indications for performing airway/lung POCUS to confirm ETT placement
  2. Describe the technique of performing airway and focused lung POCUS
  3. Distinguish between normal and abnormal airway and lung POCUS findings
  4. Distinguish between tracheal, endobronchial, and esophageal placement of ETT
  5. List the limitations of airway and lung POCUS

Case Introduction: The Postictal Toddler

Joey is a 2-year-old male with a history of epilepsy who presents to a community hospital emergency department with generalized tonic-clonic seizures of more than 45 minutes duration. After receiving 2 doses of IV midazolam, he stopped seizing. He has very shallow breathing and oxygen saturations as low as 90 percent on 2 liters of supplemental oxygen via nasal cannula. The pediatric transport team arrives to transport him to another hospital for admission and note that he is somnolent with poor respiratory effort. His current vital signs:

Vital SignFinding
Temperature37.0 C
Heart Rate115 bpm
Blood Pressure85/65
Respiratory Rate12
Oxygen Saturation (room air)92% on 2 L via nasal cannula

An end tidal carbon dioxide (ETCO2) monitor shows a ETCO2 level in the high 70s mmHg. The decision is made to intubate the patient given disordered breathing, hypercapnia, and hypoxia following medical management of seizures. The transport team would like to use POCUS to evaluate ETT placement at the outside hospital and during transport.

For simplicity, this module will focus on 3 modes of using POCUS for ETT confirmation. Collectively, these techniques can help improve evaluation.

There are many benefits of using POCUS to confirm ETT placement, such as in the following examples:

  • When compared to auscultation, POCUS ETT can be done in a loud environment where auscultation may be challenging (i.e., as may occur in transport or on scene).
  • When compared to radiography, POCUS ETT can be done rapidly at the bedside when chest radiography may be delayed or unavailable (i.e., in transport or during chest compressions).
  • When compared to capnography, POCUS ETT is helpful in scenarios of low pulmonary blood flow as in cardiac arrest or with poor tissue perfusion when capnography may be less reliable. Also POCUS can distinguish between tracheal and endobronchial ETT placement, whereas capnography cannot.
  • Unlike auscultation and capnography, POCUS ETT can confirm placement in real time, even before ventilating the patient, unlike auscultation and capnography to work.
  • POCUS ETT should typically be used as an adjunct to other methods of confirmation or in resource-limited settings, if other methods are not available.

Just as all methods of confirming ETT placement have their limitations, so does POCUS. This will be discussed in greater detail later in the module.

There are many factors to consider in the performance of ETT POCUS:

FactorOptions
Probe selectionLinear or curvilinear
Location on the anterior neckSuprasternal notch, cricoid, or thyroid cartilage
Probe orientationLongitudinal or transverse plane
TimingDynamic (while intubating) or static (for confirmation)
Evaluation techniqueDirect (visualize the ETT) or indirect (visualize lung movement0

Probe Selection

Two types of probes will be needed for POCUS ETT confirmation.

  • Use a linear probe to visualize the superficial airway and lung structures. The linear probe uses high frequency sound waves to create high resolution images of superficial structures such as the trachea and pleura.
  • Use a curvilinear probe to visualize deeper structures, such as the diaphragm. The curvilinear probe uses lower frequency sound waves to create higher resolution images of deeper structures.
POCUS ultrasound probes

Figure 1: Linear probe (left) and curvilinear probe (right)

Timing of Image Acquisition

If time permits, pre-scan the patient’s neck to locate the trachea. Adjust the gain and depth accordingly to visualize the trachea clearly in the middle of the screen.

pocus neck trachea endotracheal tube ett

Figure 2: Positioning and ultrasound images of the anterior neck anatomy for ETT placement confirmation. Left: Transverse orientation of the linear probe just above the suprasternal notch. Center: Corresponding pictorial display of the trachea and surrounding structures. Note that below the trachea is a dirty shadow artifact, resulting from the air-mucosa interface. Right: Corresponding ultrasound image of the thyroid lobes flanking the empty trachea, with the ovoid esophagus seen posterolaterally (ultrasound image by Jade Sequin).

1. Static Assessment

  • We recommend using the static assessment (i.e., after the patient is intubated), rather than dynamic (i.e., watching the ETT enter the trachea in real time) which is technically more challenging.
  • Positioning: Stand at the patient’s waist, facing the patient’s head, with the probe marker pointing towards the patient’s right (transverse plane) to confirm ETT placement in the neck. Place the linear transducer midline on the anterior neck, slightly above the suprasternal notch (figure 2, left). The orientation of the image on the screen corresponds to the probe direction. This orientation is helpful for procedural POCUS and conceptually allows for easier redirection.
  • Identify the trachea: The trachea is visible in the midline as a semicircular structure with a hyperechoic bright line (upside down U) and shadows distally (figure 2, center). Shadows are reverberation artifact from the air in the trachea (often called “dirty shadows,” or referred to as the air-mucosa interface). The thyroid overlies the trachea as a homogenous structure with the lobes extending bilaterally.
  • Identify the esophagus: The esophagus is generally posterolateral and to the left of the trachea. The esophagus is seen as a collapsed round or oval shaped structure with concentric layers, without air in it (figure 2, right).
    • Anatomy variability: A pediatric study noted that the esophagus can be seen in variable locations in relation to the cricoid ring and trachea. It was partially to the patient’s left (62%), completely to the left (20%), behind the cricoid ring (16%), and partially to the right (2%) [1].

When the ETT is placed correctly in the trachea, you should still see only a SINGLE air-mucosa interface, similar to an empty trachea. An ETT properly positioned in the trachea will have a similar ultrasonographic appearance with one air-mucosal interface as the air-filled tube will be in the trachea and the esophagus will be decompressed without air (figure 2, right).

2. Dynamic Assessment

Dynamic assessment involves watching the ETT pass into the trachea in real-time. In this technique, you will see a brief disturbance within the trachea termed the “snowstorm” which is a subtle finding (Video 1). A dynamic assessment is made more challenging with the multiple tasks and personnel at the bedside during intubation.

Video 1: Dynamic assessment of ETT placement confirmation using a linear probe in the transverse orientation on the anterior neck . With the probe marker to the patient’s right, the trachea is often on the left of the screen in relationship to the esophagus, as in this video. As the ETT enters the trachea, there is a slight disruption termed a “snowstorm” noted in this dynamic view. Video credit: Jade Sequin

Erroneous Esophageal Intubation

If the ETT is placed incorrectly in the esophagus, there will be TWO air-mucosa interfaces with reverberation artifact and posterior shadowing. This has been called the “double trachea sign” or “double tract sign” (figure 3, left). Contrast this to normal anatomy with an empty esophagus (figure 3, right).

Figure 3. Left: Double tract or double trachea sign on ultrasound, visualized when the ETT is placed incorrectly in the esophagus. Note the esophagus appears curved with dirty shadow artifact like the trachea. Right: Normal collapsed esophagus. Images credit: Jade Sequin.

Video 2: Esophageal intubation seen on ultrasound. Note the ETT entering the esophagus, generating the “double tract” or “double trachea” sign. Video used with permission by authors of [2].
Video 3: “Double tract” or “double trachea” sign and esophageal de-intubation. The video starts with the ETT in the esophagus, but then is removed. Video used with permission by authors of [2].

This indirect visualization method uses ultrasound to identify bilateral lung sliding as a means to confirm ETT placement, because this implies that both lungs are ventilated. This method is often used in conjunction with and after direct confirmation using POCUS, seeing the ETT in the trachea.

  • If the ETT is in the right main stem bronchus, ONLY the right lung will have sliding.

Ultrasound Probe Placement

Place the linear transducer on the superior, most-anterior chest wall in the mid clavicular line over the 3rd-5th intercostal space. Ensure that the probe marker is towards the head. Scan both lungs (Figures 4).

pediatric lung sliding positioning

Figure 4. Positioning of the linear probe on the patient’s anterior chest wall to check for lung sliding

Normal Lung Findings on POCUS

ultrasound lung sliding landmarks

Figure 5. Ultrasound of a normal lung: Just deep to the chest wall and ribs, the pleural line of the lung slides horizontally to and fro with each breath.This line is the first hyperechoic line deep to the rib and is the place to look for lung sliding.

Alveoli filled with air have the ARTIFACTS that are the hallmark of airway POCUS.

  • A lines (figure 6): Hyperechoic lines that are parallel to the pleural line (typically horizontal) that are caused by reverberations between the pleura and transducer. They are equidistant from the chest wall. A lines are seen with normal aerated lungs along with lung sliding
  • Z lines or comet tails: Perpendicular lines to the pleura (often appear vertical as the pleura is typically visualized as horizontal) that arise from the pleura. These lines typically do not go to the bottom of the screen.
  • Lung sliding (figure 8): Shimmering artifact of the parietal and visceral pleura sliding against each other. Lung sliding indicates that the lung visualized under the probe is filled with air and ventilated (video 4).

Figure 6. Normal lung with A lines – The most superficial hyperechoic line below the chest wall is the pleural line. The subsequent hyperechoic lines parallel and deep to the pleural line are A lines. A lines are always normal findings.

Video 4: Normal lung ultrasound: Most superficial are the chest wall tissue and 2 ribs (the circular anechoic structures). The hyperechoic line just deep to the ribs is the pleural line. Lung sliding is the subtle movement at the pleural line, referred to as “ants marching.” The hyperechoic lines horizontal and parallel to the pleural line are A lines, and the thin vertical lines are Z lines, or comet tails.

B Lines

In contrast to A lines, B lines may be visualized in patients with abnormal lungs. B lines are hyperechoic lines (typically vertical) that arise at the pleural line and go all the way to the bottom of the screen (at least 4-8 cm depth with some experts recommending to 16 cm). This is in contrast to Z lines which do not go to the bottom of the screen. The presence of multiple B lines indicates increased fluid in the interstitium of the lungs, which can be seen in conditions such as bronchiolitis and pulmonary edema (figure 7, videos 5 and 6). Note that the presence of B lines also indicate aerated lungs.

Figure 7. Lung POCUS showing A and B lines. A lines are the hyperechoic lines parallel to the pleural line. B lines are the hyperechoic projections perpendicular to the pleural line that extends to the bottom of the screen. A lines are normal, while multiple B lines may be pathogenic.

Video 5: Lung ultrasound showing multiple hyperechoic, perpendicular B lines.
Video 6: Lung ultrasound showing lung sliding and multiple B lines. Note that this image uses a curvilinear probe.

M-Mode Setting

For additional confirmation of lung sliding, press the M mode button (motion mode) without lifting the probe to visualize motion of the sliding pleura. The M-mode view represents a small narrow slice of the ultrasound image (where the bold white vertical line appears) and runs only that portion over time.

  • Lung is aerated: Looking below the pleural line level ,you will see a grainy display, known as the “sandy beach” or “seashore” signs (figure 8). You’ll find yourself feeling very relaxed when you see this, because this indicates a successfully aerated lung.
  • Lung is NOT aerated: Looking below the pleural line level, you will see multiple horizontal bar-like, striated lines instead of the grainy, sandy beach (figure 9). This is called the “barcode” or “stratosphere” sign, and may be seen in a pneumothorax or a main-stem bronchus intubation.

Figure 8: Lung ultrasound with M-mode view in a normal, aerated lung (left), showing the grainy, “sandy beach” appearance of the lines deep to the pleural line. Contrast this to an abnormal, non-aerated lung (right), showing the horizontal “barcode” appearance of the lines deep to the pleural line.

Figure 9: Another example of a normal (left) and non-aerated (right lung) in M-mode view

Ultrasound Technique

Visualize lung sliding in both 2D (also known as B mode and is the typical ultrasound mode) and M mode on the both the left and right chest.

  • Note: If the ETT is in the right mainstem bronchus, you may still see subtle movements of the pleural line on the left due to cardiac activity. The lung sliding in this case will be asymmetric with less movement of the pleural line on the left compared to right.

Alternative Causes for Abnormal Lung Sliding After Intubation

Abnormal lung sliding on ultrasound may be worrisome for an esophageal intubation, because the lungs are not aerated with PPV breaths. However, there are other causes to consider before removing the ETT for a re-intubation attempt.

1. Pneumothorax

In order to see lung sliding, visceral and parietal pleural need to be touching. With a pneumothorax, there is air in the pleural space. The parietal pleura will still be visible, but the visceral pleura and moving interface are not seen. In the M-mode view, a “barcode sign” will be present (figure 10), highlighting the importance of evaluating both 2D (B mode) and M mode if there is any doubt about lung sliding.

Figure 10: Lung POCUS demonstrating no lung sliding (“barcode sign”) in M-mode view

Video 10: Lung POCUS of a patient with a pneumothorax, showing no lung sliding for one lung in 2D view (B mode)

2. Main stem bronchus intubation

If there is no lung sliding in just one lung (especially if it occurs on the left), this may be caused by the ETT being too deep into a mainstem bronchus. This results in non-ventilation of the contralateral lung. Be aware that since the visceral and parietal pleural are still touching (unless there is also a pneumothorax), you could see some sliding movement, as the heart still causes some movement of the lungs.

3. ETT obstruction or apnea

This results in the loss of lung sliding bilaterally.

Take Away

When you see symmetric lung sliding on both sides of the chest, the ETT is in good position in the trachea.

Ultrasound Probe Placement

Use a curvilinear probe, because it gives you deeper tissue penetration than the linear probe. This allows you to better visualize the diaphragm, which is a deeper structure.

Figure 11. Left: Using a curvilinear probe with the probe marker towards the head, position it along the mid-axillary line to identify the diaphragm. Continue sliding the probe to the lower edge of the ribcage until you see the diaphragm meeting the spine along the bottom of the ultrasound image. Right: Ideal ultrasound view of the hyperechoic diaphragm. Also seen is the liver with mixed echotexture, a hypoechoic kidney, and the hyperechoic spine.

Normal Findings on POCUS (figure 11)

  • The diaphragm is a hyperechoic line, seen curving vertically on the screen, with a solid organ (liver or spleen) caudal to that.
  • The spine appears as interrupted hyperechoic structures (vertebral bodies), extending caudally from the diaphragm at the bottom of the image. The vertebral bodies shadow as all calcified structures on ultrasound do. Normally the spine is only visualized caudal to the diaphragm, because aerated lung obscures visualizing the spine in the thorax (cephalad to the diaphragm).

Ultrasound Technique

  1. Watch the movement of the diaphragm. In a patient who is paralyzed for intubation, the diaphragm will only move with delivery of positive pressure ventilation (PPV).
    • Normal: If the ETT is in good position, with a PPV breath, the diaphragm moves caudal toward the abdomen as the lungs inflate, and upwards when the lungs deflate (video 7). In M mode, normal diaphragm movement creates a smooth wave with inspiration and expiration (video 8).
    • Esophageal intubation: The diaphragm moves in the reverse direction than is expected. With a PPV breath, the diaphragm moves cephalad, because the abdominal cavity is getting inflated.
    • Mainstem bronchus intubation: The diaphragm on the side of the main stem intubation (typically right) will show exaggerated motion toward the abdomen during PPV. The diaphragm on the contralateral side, where the lung is not properly ventilated will either not move or move paradoxically cephalad during PPV. In M-mode, there is no sinusoidal, wave pattern for the diaphragm in the non-ventilated lung (video 9)
Video 7: Ultrasound view showing diaphragmatic movement with regular breaths. The diaphragm pushes the spleen and kidneys caudal into the abdomen (to the right of the screen) with each breath.
Video 8: Ultrasound M-mode view of the diaphragm with regular breaths. Normal diaphragmatic movement is demonstrated by the hyperechoic sinusoidal line (at 12 cm depth) at the bottom of the screen.
Video 9: Ultrasound of the diaphragm in M-mode setting. The hyperechoic diaphragm does not move either in 2D (top) or M mode (bottom). This could be seen if the ETT is in the esophagus or in a mainstem bronchus, for example.

Abnormal Findings While Assessing Diaphragmatic Movement

1. Hemothorax or pleural effusion

Best seen at the costophrenic angle because fluid is dependent, a hemothorax or effusion will appear anechoic or hypoechoic. Additionally the spine can now be seen cephalad to the diaphragm, known as the “spine sign,” because air now no longer obscures the view of the spine (figure 12). A hemothorax and pleural effusion can look the same on POCUS. The clinical scenario aids in determining the potential cause of the fluid.

Figure 12. Left: Normal lung showing the spine only caudal to the hyperechoic diaphragm. Right: Hemothorax on lung POCUS. Right: Lung POCUS showing a pleural effusion, suggested by the hypoechoic fluid collection and “spine sign”.

Take Away

In a patient paralyzed for intubation and thus with no spontaneous respirations, the ETT is in good position when you see movement of the diaphragm towards the abdomen on both sides of the chest with PPV.

Lin et al. published a systematic review of bedside ultrasound for tracheal tube verification in pediatric patients. The authors proposed the following algorithm (figure 13) for confirming ETT placement.

Figure 13: Algorithm for using and interpreting POCUS to confirm ETT placement in pediatric patients. Image permission granted by author of [3].

  • Operator dependent: As with all POCUS studies, image acquisition and interpretation is operator dependent. The more you practice the concepts and techniques in this module, the more comfortable you will be in obtaining and accurately interpreting these images.
  • Challenging anatomy: It is difficult to perform airway POCUS on a small neck, with a cervical collar in place, or if there is subcutaneous emphysema (air obscures structures below).
  • Depth: Airway POCUS is not able to determine the exact depth of ETT within the trachea, but can be a good surrogate of position:
    • Visualization of the ETT cuff at the suprasternal notch using a linear probe in the transverse orientation correlated with the ETT depth on chest x-ray in 57/60 children (Cl, 86-98%) in a single center, prospective observational study [11]
    • If you are concerned about a mainstem bronchus intubation, slowly pull back on the ETT to see if the lung opposite the main stem intubation starts sliding. If the depth of the tube at the gums/teeth/lips seems appropriate and one side still does not have sliding, there may be a pneumothorax on that side.
  • False negative for ETT placement: In the rare patient with thyroid gland calcifications, there may falsely appear to be 2 shadowing structures (double tract sign), even when the ETT is correctly in the trachea. Calcifications shadow. This can be anticipated with pre-scanning the neck before intubation.
  • False positive for ETT placement: If the esophagus is structurally immediately posterior to the trachea, you wouldn’t see a “double tract” sign if the ETT is in the esophagus. But you should have other signs soon if the ETT is in the wrong place such as lack of ETCO2 and lack of breath sounds.
  • Lack of lung sliding may not always be due to pneumothorax or right mainstem ETT intubation. Other explanations include:
    • ETT obstruction
    • Apnea in a spontaneously breathing patient or no breath being delivered to a patient who is intubated.
    • Lack of sliding or “barcode” (on M-mode) should be interpreted with caution in patients who have parenchymal lung disease or pleurodesis (a procedure where the pleura is surgically or mechanically adhered to the chest wall) making the lung appear not to slide. These patients may not have pneumothorax nor a main stem intubation on the other side.

Adult Literature

In a metanalysis of 30 adult studies assessing the use of POCUS for ETT placement confirmation, the overall sensitivity was 0.98 (95% CI 0.97–0.99) and specificity was 0.96 (95% CI 0.90–0.98) [4].

Other studies have evaluated using various techniques for POCUS evaluation of ETT placement, with no clear winner (Table 1).

VariableSourceFindingsRecommendation
Probe type: Linear vs CurvilinearSahu 2020 [4]No differenceLinear probe
Technique: Static vs DynamicSahu 2020 [4] No differenceStatic technique
Probe placement:

  • Transverse at suprasternal notch
  • Longitudinal at cricoid or thyroid cartilage
Lonchena 2017 [5]Successful ETT visualization

  • Suprasternal notch: 100%
  • Cricoid: 70%
  • Thyroid: 40%
Place probe transverse in suprasternal notch in the anterior neck
Table 1: Published studies in the adult population, comparing different techniques for confirming ETT placement with POCUS.

Pediatric Literature

The pediatric literature for the application of POCUS to evaluate ETT placement is not as robust compared to adult studies; however, it is still compelling. A systematic review by Lin et al. in 2016 [3] included studies that evaluated intubations using direct visualization of tube tip in trachea, diaphragmatic movement and/or lung sliding. All modalities had high sensitivities though the esophageal intubation rates included in the studies were relatively low (Table 2).

StudyEndotracheal IntubEsophageal IntubPOCUS Technique UsedSensitivitySpecificity
Galicinao 2007 [6]501Direct visualization of tube tip in trachea1.00 (0.93-1.00)1.00 (0.03-1.00)
Alonso Quintela 2014 [7]315Direct visualization of tube tip in trachea0.92 (0.75-0.99)1.00 (0.48-1.00)
Hsieh 2004 [8]612Diaphragmatic or lung pleural movement1.00 (0.94-1.00)1.00 (0.16-1.00)
Kerrey 2009 [9]1270Diaphragmatic or lung pleural movement1.00 (0.97-1.00)Not reported
Table 2: Summary of pediatric studies that evaluated using POCUS for ETT confirmation by direct visualization of the tube in the trachea over the anterior neck or indirectly by assessing for diaphragmatic or pleural movement.

Another systematic review of using POCUS to confirm ETT position in the pediatric population by Jaeel et al [10], found that POCUS was comparable to confirming ETT placement by x-ray and capnography for patients outside the neonatal intensive care unit. They concluded that POCUS agreed with x-ray or capnography confirmation in 83-100% of cases. Compared to x-rays, POCUS had a sensitivity of 91-100%.

Case Resolution

After administration of fentanyl, midazolam, and rocuronium, the patient was intubated with a 4.0 cuffed ETT by direct laryngoscopy with a Macintosh blade.

POCUS was used to confirm ETT placement by the transport team in the community hospital ED. Specifically, the provider directly visualized the in the anterior neck (with a single air-mucosa interface), the presence of bilateral lung sliding, and movement of the diaphragm towards the abdomen with PPV. End tidal CO2 further confirmed accurate placement. Once loaded into the ambulance, the ETT was again confirmed to be in the trachea.

Video 11: POCUS showing bilateral lung sliding
Video 12. POCUS showing diaphragmatic movement down to the abdomen with breathing.

Learn More…

References

  1. Tsung JW, Fenster D, Kessler DO, Novik J. Dynamic anatomic relationship of the esophagus and trachea on sonography: implications for endotracheal tube confirmation in children. Journal of Ultrasound in Medicine. 2012 Sep;31(9):1365-70. PMID 22922616
  2. Tessaro MO, Salant EP, Arroyo AC, Haines LE, Dickman E. Tracheal rapid ultrasound saline test (TRUST) for confirming correct endotracheal tube depth in children. Resuscitation. 2015 Apr 1;89:8-12. PMID 25238740
  3. Lin MJ, Gurley K, Hoffmann B. Bedside Ultrasound for Tracheal Tube Verification in Pediatric Emergency Department and ICU Patients: A Systematic Review. Pediatr Crit Care Med. 2016;17(10):e469-e476. PMID 27487913
  4. Sahu AK, Bhoi S, Aggarwal P, et al. Endotracheal tube placement confirmation by ultrasonography: A systematic review and meta-analysis of more than 2500 patients. J Emerg Med. 2020 Aug 1;59(2):254-64. PMID 32553512
  5. Lonchena T, So S, Ibinson J, Roolf P, Orebaugh SL. Optimization of ultrasound transducer positioning for endotracheal tube placement confirmation in cadaveric model. J Ultrasound Med. 2017 Feb;36(2):279-84. PMID 28072483
  6. Galicinao J, Bush AJ, Godambe SA. Use of bedside ultrasonography for endotracheal tube placement in pediatric patients: A feasibility study. Pediatrics 2007; 120:1297–1303. PMID 18055679
  7. Alonso Quintela P, Oulego Erroz I, Mora Matilla M, et al: [Usefulness of bedside ultrasound compared to capnography and radiograph for tracheal intubation]. An Pediatr (Barc) 2014; 81:283–288. PMID 24560730 
  8. Hsieh KS, Lee CL, Lin CC, Huang TC, Weng KP, Lu WH. Secondary confirmation of endotracheal tube position by ultrasound image. Crit Care Med. 2004 Sep;32(9 Suppl):S374-7. PMID 15508663
  9. Kerrey BT, Ceis GL, Quinn AM. A prospective comparison of diaphragmatic ultrasound and chest radiography to determine endotracheal. Pediatrics. 2009;123:1039-43. PMID 19414520
  10. Jaeel P, Sheth M, Nguyen J. Ultrasonography for endotracheal tube position in infants and children. Eur J Pediatr. 2017 Mar;176(3):293-300. PMID 28091777
  11. Uya A, Gautam NK, Rafique MB, et al. Point-of-Care Ultrasound in Sternal Notch Confirms Depth of Endotracheal Tube in Children. Pediatr Crit Care Med. 2020;21(7):e393-e398. PMID 32168296

Additional Reading

  1. Adhikari S, Blaivas M. The Ultimate Guide to Point-of-Care Ultrasound-Guided Procedures. 1st Ed. Springer Nature; 2020.
  2. Blaivas M, Tsung JW. Point-of-care sonographic detection of left endobronchial main stem intubation and obstruction versus endotracheal intubation. J Ultrasound Med. 2008;27(5):785-789. doi:10.7863/jum.2008.27.5.785. PMID 18424655
  3. Chou EH, Dickman E, Tsou PY, et al. Ultrasonography for confirmation of endotracheal tube placement: a systematic review and meta-analysis. Resuscitation. 2015;90:97-103. doi:10.1016/j.resuscitation.2015.02.013. PMID 25711517
  4. Hoffmann B, Gullett JP, Hill HF, et al. Bedside ultrasound of the neck confirms endotracheal tube position in emergency intubations. Ultraschall Med. 2014;35(5):451-458. doi:10.1055/s-0034-1366014. PMID 25014479
  5. Lahham S, Baydoun J, Bailey J, et al. A Prospective Evaluation of Transverse Tracheal Sonography During Emergent Intubation by Emergency Medicine Resident Physicians. J Ultrasound Med. 2017;36(10):2079-2085. doi:10.1002/jum.14231. PMID 28503749
  6. Marciniak B, Fayoux P, Hébrard A, et al. Airway management in children: ultrasonography assessment of tracheal intubation in real time?. Anesth Analg. 2009;108(2):461-465. doi:10.1213/ane.0b013e31819240f5. PMID 19151273
  7. Mori T, Nomura O, Hagiwara Y, Inoue N. Diagnostic Accuracy of a 3-Point Ultrasound Protocol to Detect Esophageal or Endobronchial Mainstem Intubation in a Pediatric Emergency Department. J Ultrasound Med. 2019;38(11):2945-2954. doi:10.1002/jum.15000. PMID 30993739
  8. Prada G, Vieillard-Baron A, Martin AK, et al. Tracheal, Lung, and Diaphragmatic Applications of M-Mode Ultrasonography in Anesthesiology and Critical Care. J Cardiothorac Vasc Anesth. 2021;35(1):310-322. doi:10.1053/j.jvca.2019.11.051. PMID 31883769
  9. Sethi AK, Salhotra R, Chandra M, Mohta M, Bhatt S, Kayina CA. Confirmation of placement of endotracheal tube – A comparative observational pilot study of three ultrasound methods. J Anaesthesiol Clin Pharmacol. 2019;35(3):353-358. doi:10.4103/joacp.JOACP_317_18. PMID 31543584
  10. Sim SS, Lien WC, Chou HC, et al. Ultrasonographic lung sliding sign in confirming proper endotracheal intubation during emergency intubation. Resuscitation. 2012;83(3):307-312. doi:10.1016/j.resuscitation.2011.11.010. PMID 22138058
  11. Singh M, Chin KJ, Chan VW, Wong DT, Prasad GA, Yu E. Use of sonography for airway assessment: an observational study. J Ultrasound Med. 2010;29(1):79-85. doi:10.7863/jum.2010.29.1.79. PMID 20040778
  12. Weaver B, Lyon M, Blaivas M. Confirmation of endotracheal tube placement after intubation using the ultrasound sliding lung sign. Acad Emerg Med. 2006;13(3):239-244. doi:10.1197/j.aem.2005.08.014. PMID 16495415
By |2022-04-30T19:47:20-07:00May 2, 2022|ALiEMU, Pediatrics, PEM POCUS, Radiology, Ultrasound|

PEM POCUS Series: Pediatric Ultrasound-Guided Fascia Iliaca Block

PEM POCUS fascia iliaca block

Read this tutorial on the use of point of care ultrasonography (POCUS) for pediatric fascia iliac block. Then test your skills on the ALiEMU course page to receive your PEM POCUS badge worth 2 hours of ALiEMU course credit.

Take the ALiEMU PEM POCUS: Pediatric Fascia Iliac Block Quiz

Module Goals

  1. List indications of performing a pediatric point-of-care ultrasound fascia iliaca nerve block (POCUS-FINB)
  2. List the limitations of POCUS-FINB
  3. Describe the technique for performing POCUS fascia iliaca nerve block 
  4. Identify anatomical landmarks accurately on POCUS
  5. Calculate the maximum safe weight-based local anesthetic dose
  6. Recognize the signs and symptoms of local anesthetic systemic toxicity (LAST) and describe the appropriate management 

Case Introduction: Child with thigh pain

Sarah is a 3-year-old girl who comes into the emergency department complaining of acute thigh pain that started 30 minutes ago. She was playing on a trampoline when she accidentally fell off. She had immediate pain to the left thigh and she’s been unable to walk since the fall. Parents carried her in to the emergency department for further evaluation.

On arrival, her vital signs are:

Vital SignFinding
Temperature97.5 F
Heart Rate130 bpm
Blood Pressure97/50
Respiratory Rate22
Oxygen Saturation (room air)100%

 
She is in distress secondary to pain. She has a normal HEENT, neck, cardiac, respiratory, abdominal, and back examination. She points to her left anterior thigh when you ask her where her pain is. She has limited range of motion with flexion and extension of her left hip and complains of pain with any manipulation. Her leg is externally rotated and slightly shortened when compared to the opposite leg. She cries when you palpate any part of her leg, but is able to range her knee, ankle, and foot fully. She has 2+ dorsalis pedis and posterior tibialis pulses with intact sensation to light touch throughout. 
 
Given her pain with range of motion at her hip and tenderness to palpation to the femur, you obtain a thigh radiograph, which shows a femoral shaft fracture. The orthopedic team is notified about the patient in order to discuss pain control and possible next steps. You ask your self several questions to help you best care for this child. 
  1. What can we do for pain control in this patient? Are there opioid-sparing options?
  2. Can nerve blockade be utilized in this case?
  3. What local anesthetic is appropriate, and what is a safe dose?
  4. What safety precautions need to be considered for performing a regional block?
You consult with the orthopedic team and discuss performing a Point-of-Care Ultrasound-Guided Fascia Iliaca Nerve Block (POCUS-FINB).

The fascia iliaca nerve block anesthetizes the femoral nerve (FN), lateral femoral cutaneous (LFC) nerve, and obturator nerve (ON), as demonstrated in the lower leg nerve anatomy drawing below.

 

anatomy leg

Figure 1. Thigh and lower leg sensory nerve anatomy. The expected distribution of a fascia iliaca block (via infrainguinal approach described here) includes the FN – Femoral Nerve, often but not always the LFC – Lateral Femoral Cutaneous Nerve, and unreliably the ON – Obturator Nerve.  (Illustration by Dr. Muki Kangwa)

 

The fascia iliaca block thus can assist with pain control for:

  1. Femoral neck and femoral shaft fractures
  2. Patella injuries 
  3. Anterior thigh wound care

Clinicians should keep in mind relative contraindications to this procedure particularly in nonverbal or peri-verbal patients. See the exclusion criteria from the UCSF Benioff Children’s Hospital Oakland institutional protocol:

  1. Young, preverbal patients <2 years old (lower age cutoff may range from 2-5 years dependent on orthopedic consultant)
  2. Concern for acute compartment syndrome of the thigh
    • Tense or firm compartment on palpation
    • Expanding hematoma of the thigh
    • Pain out of proportion to injury
    • Neurologic deficit in femoral distribution
    • Mechanism: crush injury or open fracture
  3. Any child with an American Society of Anesthesia score of >2
  4. Neurologic deficits in the femoral distribution (specifically loss of touch sensation to the anterior thigh)
  5. Signs of vascular injury, coagulopathy, hemodynamic instability, and/or suspected multi-organ system trauma  
  6. Patients at high risk for local anesthetic toxicity (e.g., cardiac/hepatic dysfunction, metabolic/mitochondrial disease, infants <6 months)

Using ultrasonography to perform a fascia iliaca nerve block helps to identify key anatomical landmarks for appropriate administration of local anesthetic. The point-of-care ultrasound-guided fascia iliaca nerve block (POCUS-FINB) allows us to identify the area of interest, which is underneath the fascia iliaca fascial plane. Note that this plane is just deep to femoral artery and vein, in contrast to the fascia lata plane, which is superior to the femoral artery and vein (Figure 2). The area is best visualized distal to the inguinal canal and proximal to the bifurcation of the femoral artery.  

 

fascia iliaca anatomy

Figure 2. Relevant anatomy for the fascia iliaca block for the right groin, demonstrating the location of the fascia iliaca and fascia lata planes (illustration by Dr. Muki Kangwa)

fascia iliaca equipment supplies

Figure 3. Key supplies needed for the ultrasound-guided fascia iliaca block

 

  1. Sterile gel 
  2. Chlorhexidine/alcohol wipes 
  3. Sterile ultrasound probe cover (or equivalent such as Tegaderm dressing, sterile glove, or condom)
  4. 22-gauge spinal/block needle (50-80 mm) with attached tubing primed with sterile saline
  5. Local anesthetic
    • Superficial: 1% lidocaine (buffered, if available) for skin wheal via 30G needle, or LMX, or EMLA cream 
    • Block: Long-acting local anesthetic
  6. 10-20 cc syringes (depending on child’s weight)
  7. Sterile saline flushes 
  8. Tegaderm dressing to label block after completion

Table 1. Local anesthetic medications, their pharmacokinetics, and weight-based maximum dosages [1, 2]

 

A long-acting local anesthetic (e.g., ropivacaine or bupivacaine)  is preferred for this block. Ropivacaine is the preferred anesthetic, because it is thought to be less lipophilic than bupivacaine and, as such, less cardiotoxic and neurotoxic. Minimizing the risk of local anesthetic toxicity is particularly relevant to fascial plane blocks, which remain far from the neurovascular bundle and thus require higher volumes of local anesthetic. This higher volume allows for bathing of the nerve via anesthetic tracking along the fascial plane. Table 1 above illustrates the pharmacokinetics and weight-based dosing maximums for the various local anesthetics.

Table 2 provides guidance on the fascia iliaca block volumes with the medication diluted in 0.9% normal saline to increase the volume. The suggested volumes of local anesthetic and saline depend on the type and concentration of local anesthetic also well as the patient’s ideal body weight, which impacts both the relative size of the potential space in the fascial plane as well as the maximum safe dose.

Table 2. Suggested Fascia Iliaca Block Total Volumes with Local Anesthetic + 0.9% Normal Saline [1, 3, 4]

1. Consult with orthopedist to discuss appropriateness of block.

2. Perform and document a neurovascular and compartment exam prior to and after block.

  • Sensation
    • Anterior thigh (femoral)
    • Medial shin/calf (saphenous/femoral)
    • Lateral foot (sural)
    • Plantar surface of foot/heel (tibial)
    • Dorsal surface of foot (superficial peroneal)
    • 1st webspace (deep peroneal)
  • Motor
    • Great toe extension (extensor hallucis longus)
    • Great toe flexion (flexor hallucis longus)
    • Foot dorsiflexion (tibialis anterior)
    • Foot plantar flexion (gastrocnemius/soleus)
  • Vascular
    • Dorsalis pedis
    • Posterior tibial
    • Capillary refill

3. Ensure informed consent with patient and family.

  • In addition to discussion of risks/benefits/alternatives, consider the relative need for pre-traction/pre-op pain control vs. post-op pain control. Depending on the dose of local anesthetic and timing of operation, a subsequent intra-operative block may or may not be possible.

4. Position the patient supine with hip and knee in extension.

5. Anticipate the child’s anxiety during the procedure.

  • Pro-tip: Depending on the age of the child, the presence of a guardian can be helpful in keeping the child calm and cooperative while undergoing the procedure.
  • It may be helpful to have a dedicated person to hold the limb of interest during the procedure.
  • Involve a childlife specialist, if available.
  • Offering the child a toy, book, or phone/tablet for distraction during the procedure can also help ease anxiety. 
  • Intranasal or intravenous midazolam may be needed for anxiolysis.

6. Select a linear high frequency ultrasound transducer with a wide footprint.

Figure 4. Ultrasound linear transducer with wide footprint and appropriate ultrasound musculoskeletal setting

 

7. Apply a single-use probe cover.

8. Ensure proper ergonomics and positioning.

  • Adjust the height of the bed.
  • Stand on the side of the affected leg.
  • Position the ultrasound machine on the opposite side of the bed such that the ultrasound screen is directly in line of sight with the affected leg us without rotating one’s head.

Figure 5. Appropriate patient, proceduralist, and ultrasound positioning with POCUS machine across from the affected leg

 

9. Place the transducer parallel to the inguinal canal.

  • Perform a survey scan to identify landmarks starting from the inguinal canal (Figure 6).
  • Aim the probe marker towards the patient’s right. This ensures that the screen image directionally matches the body part being scanned.

Figure 6. Linear ultrasound probe placement parallel to the inguinal ligament with probe marker (red dot) aimed towards the patient’s right (illustration by Dr. Muki Kangwa)

10. Ensure immediate intralipid availability

  • Key step: Before starting your procedure, confirm availability of intralipid, the antidote for local anesthetic toxicity.
    • Dose: 1.5 ml/kg bolus over 1 minute
  • Place patient on cardiac monitor.
  • Review the weight-based maximum safe dose of local anesthetic, based on patient’s ideal body weight if they are overweight.
  • Local anesthetic maximum dose calculator (MDCalc)

11. Perform ultrasound survey scan and identify the anatomical landmarks (Figure 7)

  • Muscles: Iliopsoas, sartorius
  • Neurovascular bundle: Femoral nerve, artery, and vein (most medial)
  • Fascia: Fascia lata and fascia iliaca

Figure 7. POCUS image of left hip demonstrating the normal anatomy of the femoral artery (FA), femoral vein (FV), fascia iliaca, fascia lata, femoral nerve, and iliopsoas muscle (left is medial and right is lateral)

 

12. Anesthetize your needle insertion point (adjacent to the lateral edge of the ultrasound probe).

  • Use with 1% buffered lidocaine, if available.
  • Alternatively, apply topical lidocaine, such as LMX or EMLA on the desired area at least 30 minutes prior to the start of the procedure.

13. Prime the needle and tubing with normal saline.

  • The normal saline in the tubing and needle will hydro-dissect the fascial planes prior to injecting the local anesthetic. This helps mitigate the risk for potential local anesthetic toxicity. Furthermore, it ensures appropriate fascial spread prior to injection of the anesthetic, allowing for better visualization of the anatomy and a safe window for anesthetic injection.
  • An alternative practice is to prime the needle and tubing with the diluted local anesthetic.

14. Insert the block/spinal needle.

  • Visualize the length of the needle in-plane and the needle tip at all times.
  • Warning: The needle shaft can easily be confused for the needle tip if the probe is not adequately oriented in parallel with the needle along the entire length. Make subtle rotations in the probe to ensure that the true needle tip is visualized.

15. Identify the femoral nerve.

  • Be sure to remain lateral the the femoral nerve (~2 cm). It is NOT necessary to be directly adjacent to the nerve, which increases the risk of nerve injury.
  • Use the ‘fanning’ technique to elicit anisotropy and identify the femoral nerve. The nerve is DEEP the fascial plane and lateral to the femoral artery. A common mistake is to misidentify the adipose tissue, which lies SUPERFICIAL to the fascial plane and is immediately lateral to the femoral artery, as the femoral nerve (Figure 8). 

Figure 8. POCUS image of the left hip during a fascia iliac block procedure. The adipose tissue (pink) can be confused for the femoral nerve (yellow) which lies below the fascia iliaca (red). The local anesthetic (hypoechoic) is hydrodissecting between the vascular bundle and femoral nerve. FA=femoral artery.

 

16. Puncture the needle through the fascia iliaca.

  • Keep your neurovascular bundle in the corner of your screen as you advance your needle in order to visualize your saline and local anesthetic as you hydro-dissect the nerve from the fascia.
  • Be aware of the patient’s comfort throughout the procedure.

17. Practice key safe injection techniques.

  • Ensure excellent, real-time needle and needle tip visualization on ultrasound.
  • Aspirate and look for blood once the needle is below the fascia iliaca to confirm that you will not inject into the vasculature.
  • Hydrodissect the fascial plane with 2-5 mL of normal saline. You will visualize the saline migrating medially towards the neurovascular bundle. Make adjustments in depth to find the correct plane.
  • Inject small aliquots (2-5 mL at a time) of local anesthetic. Aspirate between each aliquot to check for blood, allowing time (circulation cycle) between aliquots to monitor the patient for signs of local anesthetic systemic toxicity.

Video 1. POCUS clip of a traditional femoral nerve block block showing hydrodissection. The needle is seen directly below the bright fascia iliaca with anechoic (black) saline injected into the fascial plane. Note that in this clip, the needle tip is directly adjacent to the nerve as in a traditional femoral nerve block, rather than more laterally as in a fascia iliaca block. 

 

Video 2. POCUS clip showing a fascia iliaca block hydrodissection. In comparison to Video 1, this clip shows the needle directly below the bright fascia iliaca with anechoic (black) saline infected into the fascial plane. Note the difference in the needle positioning in comparison to the nerve. This is the correct positioning of your needle, more lateral to the neurovascular bundle compared to the needle positioning in video 1. Video courtesy of Dr. Arun Nagdev (highlandultrasound.com

 

Video 3. POCUS clip showing a fascia iliaca block hydrodissection. The pulsatile femoral artery can be seen medially, and the femoral nerve can be seen being displaced downwards below the fascial plane.

 

18. Instill the appropriate volume of long-acting anesthetic.

  • Once the needle is appropriately positioned deep to the fascia iliaca plane, carefully and incrementally instill the weight-based volume of either ropivacaine or bupivacaine, utilizing the safe injection techniques described in step 17.

19. Label your block and document in the medical record.

  • Label the block location with a Tegaderm dressing noting time and date of procedure.
  • Document the procedure in real-time, including type and dose of local anesthetic, to ensure accurate and timely communication with multidisciplinary care team (e.g., anesthesia, in order to avoid cumulative local anesthetic overdose).

20. Monitor the patient post-procedure.

  • Maintain the patient on a cardiac monitor to watch for local anesthetic systemic toxicity for 30 minutes post-block.
  • Re-evaluate the patient for efficacy of the block.

There are many errors that can make defining the relevant sono-anatomy difficult, but there are 2 common errors that are easily corrected by small changes in probe placement.

1.  Error: Probe placement distal to femoral artery bifurcation

Problem: In order to get the view needed for a successful block, the operator must image the vasculature at the level of the common femoral artery, prior to its bifurcation. When distal to the common femoral artery, the structures that are seen are usually the superficial and deep femoral arteries (Figure 9 and Video 4). At this level, the femoral nerve and the fascia iliaca can be difficult to visualize.

Solution: Slide the probe cephalad and position it just inferior to the inguinal ligament. The common femoral artery is well-visualized at this level.

Figure 9. Arterial anatomy of the thigh, adapted from Wikimedia Commons (left); POCUS image of the femoral artery bifurcation. which is too distal for fascia iliaca block (right)

 

Video 4. POCUS clip showing a femoral artery bifurcation, which is too distal for the fascia iliaca block

 

2. Error: Incorrect probe angle

Problem: If the probe is not perpendicular to the common femoral artery, the artery will be visualized, but the fascia iliaca and iliopsoas muscle can be difficult to locate.

Solution: Keep the probe parallel to the inguinal ligament, which aligns it perpendicularly to the common femoral artery (Figure 10).

 

Figure 10. Proper ultrasound probe positioning means placing the probe parallel to the inguinal canal and perpendicular to common femoral artery. Grey: probe with probe marker to patients right, Purple: inguinal canal, Red: femoral artery (illustration by Dr. Muki Kangwa)

  1. Quadriceps muscle spasms: These are usually secondary to anesthetic injection directly into the femoral nerve.
  2. Delayed recognition of compartment syndrome: This is less common in the thigh compartment compared to the lower leg.
    • Fractures account for approximately 75% of cases of acute extremity compartment syndrome. The risk increases with increasing severity of the fracture (e.g., comminuted fractures). The tibia is involved most often, with acute compartment syndrome developing in approximately 1-10% of such fractures.
  3. Local anesthetic systemic toxicity (LAST) is a rare event resulting from dose-dependent blockade of the sodium channels in the cardiovascular and central nervous system.
    • Risk of LAST can be mitigated by:
      • Calculating the maximum safe dose for the anesthetic and patient’s weight
      • Real-time cardiac monitoring
      • Continuous needle visualization to ensure proper placement of anesthetic
      • Aspirating prior to each injection
      • Hydrodissection of fascial plane with saline prior to anesthetic
      • Injection of small aliquots and monitoring for signs/symptoms during circulation cycle
      • Monitoring of the patient for 30 minutes as per American Society of Regional Anesthesia and Pain Management recommendations.
    • Mild-moderate LAST toxicity
      • Oral numbness and tingling
      • Metallic taste
      • Tinnitus
      • Nausea and dizziness
    • Severe LAST toxicity
      • Tremors
      • Convulsions
      • Bradycardia and other cardiac arrhythmias
      • Respiratory depression
      • Hypotension
      • Cardiac arrest
    • Treatment
      • Lipid emulsion (20%) – 1.5 mL/kg followed by continuous infusion at 0.25 mL/kg/min
      • For more local anesthetic systemic toxicity resources, visit asra.com

Nerve blockade is being performed widely by many emergency medicine physicians, and is now becoming standard of care in an attempt to reduce the amount of opiates used particularly in the elderly with femoral fractures. However, ultrasound guided nerve blockade it is not a core skill found in most pediatric emergency medicine curricula, and the lack of educational training presents a barrier to implementation within Pediatric Emergency Medicine. Prior studies of fascia iliaca nerve blockade have shown great success and improved pain control. A few of these studies are summarized below.

 

YearAuthorsTitleStudy TypeFindings
2007Wathen JE et al.Randomized Controlled Trial Comparing a Fascia Iliaca Compartment Nerve Block to a Traditional Systemic Analgesic for Femur Fractures in a Pediatric Emergency Department (PMID 17210208)Randomized controlled trialFascia iliaca compartment block performed by pediatric emergency medicine attendings and fellows for children ages 15 months to 18 years with a femur fracture can result in lower pain scores, longer duration of analgesia, and higher staff satisfaction in comparison with traditional analgesia.
2012Frenkel O et al.Ultrasound-guided Femoral Nerve Block for Pain Control in an Infant with a Femur Fracture due to Non-accidental Trauma (PMID 22307191)Case reportCase report of a 3-month-old female with a subtrochanteric femoral neck fracture due to non-accidental trauma requiring multiple doses of IV pain medication. An ultrasound-guided femoral nerve block was performed using 2 mL of 0.25% bupivacaine for placement into a Pavlik harness. The patient only required 1 dose of analgesia in 18 hours following the femoral nerve block.
2014Turner AL et al.Impact of Ultrasound-guided Femoral Nerve Blocks in the Pediatric Emergency Department (PMID 24651214)Retrospective cohort studyIn a pre- and post-implementation retrospective cohort study of children with femur fractures in a pediatric ED, an ultrasound-guided femoral nerve block was associated with a 3-times longer duration of initial analgesia (6 hr vs 2 hr), lower total morphine dose, and fewer nursing interventions in comparison with systemic analgesia alone.
2014Neubrand T et al.Fascia Iliaca Compartment Nerve Block Versus Systemic Pain Control for Acute Femur Fractures in the Pediatric Emergency Department (PMID 24977991)Retrospective chart studyRetrospective chart review of children receiving systemic analgesia (control) vs fascia iliaca nerve block evaluating effectiveness and adverse effects. Outcomes included total doses of systemic medications received and comparison of pre- and post-intervention pain scores. Effectiveness, as measured by pain scores and total doses of systemic analgesia, was improved in the fascia iliaca nerve block group versus the control. There was no difference in adverse events between the groups.
2022Heffler MA et al.Ultrasound-Guided Regional Anesthesia of the Femoral
Nerve in the Pediatric Emergency Department (PMID 35245015)
Multicenter retrospective case seriesUltrasound-guided regional anesthesia of the femoral nerve (fascia iliaca compartment block, n=70; femoral nerve block, n=15) was performed by residents, fellows, and attendings with varying degrees of formal POCUS training for pediatric patients aged 50 days to 15 years at 6 pediatric emergency departments across North America. There were no reported complications across a heterogenous patient population at these 6 tertiary care centers, supporting the safety and generalizability of these techniques.
Table 4. Published studies supporting effectiveness of POCUS fascia iliaca nerve block in pediatric patients.

Full Video of Fascia Iliaca Nerve Block 

Video 5. POCUS clip of the complete fascia iliaca block procedure. The clip starts with an initial anatomy scan, followed by needle visualization, and lastly hydrodissection.

 

    Case Resolution

    Given that the patient remains in significant painful distress despite non-opioid analgesia, you decide to incorporate POCUS-FINB to your evaluation and treatment.

    The patient is evaluated by the on-call orthopedic team member and is found to have no evidence of neurovascular compromise or signs and symptoms of compartment syndrome. You confirm the availability of lipid emulsion (intralipid) in the emergency department and calculate the maximum safe dose of your anesthetic.

    • The patient weighs 20 kg.
    • The MAXIMUM safe dose of 0.2% ropivacaine (3 mg/kg) equals 60 mg, or 30 mL.
    • Looking at your institutional guidelines and Table 2 you decide to use 12 mL, which is well underneath this maximum dose.
    • You add 3 mL of saline to increase the overall fluid volume to reach the weight-based target goal of 15 mL volume for the fascia iliaca procedure.
     

    Tables 1 and 2 (cropped from original tables): Local anesthetic medications and their pharmacokinetics, weight-based maximum doses, and suggested total volumes (anesthetic + 0.9% normal saline) for fascia iliaca block

     

    The patient undergoes a safe and effective fascia iliaca nerve block with her pain score improving from a 10 to a 2. The orthopedic team is able to place the patient into traction prior to transfer to the operating room.

    Orthopedic Clinic Follow-Up

    At her orthopedic follow-up visit 4 weeks later, she’s doing well with minimal pain. Her follow up x-ray demonstrates appropriate healing with new bone formation. 

     

    Learn More…

    References

    1. Suresh S, Polaner DM, Coté CJ. 42 – Regional Anesthesia. In: Coté CJ, Lerman J, Anderson BJ, eds. A Practice of Anesthesia for Infants and Children (Sixth Edition). Elsevier; 2019:941-987.e9.
    2. Gadsen J. Local Anesthetics: Clinical Pharmacology and Rational Selection. The New York School of Regional Anesthesia website, October 2013.
    3. Dalens B. Lower extremity nerve blocks in pediatric patients. Techniques in Regional Anesthesia and Pain Management. January 2003 2003;7(1):32-47.
    4. Karmakar MK, Kwok WH. 43 – Ultrasound-Guided Regional Anesthesia. In: Coté CJ, Lerman J, Anderson BJ, eds. A Practice of Anesthesia for Infants and Children (Sixth Edition). Elsevier; 2019:988-1022.e4.

     

    Additional Reading

    1. Black KJ, Bevan CA, Murphy NG, et al. Nerve blocks for initial pain management of femoral fractures in children. Cochrane Database Syst Rev. 2013(12):CD009587.
    2. Bretholz A, Doan Q, Cheng A, et al. A presurvey and postsurvey of a web- and simulation-based course of ultrasound-guided nerve blocks for pediatric emergency medicine. Pediatr Emerg Care. 2012;28(6):506-9. PMID 22653464
    3. Chenkin J, Lee S, Huynh T, et al. Procedures can be learned on the Web: a randomized study of ultrasound-guided vascular access training. Acad Emerg Med. 2008;15(10):949-954. PMID 18778380
    4. Coté, Charles J., et al. “Chapter 42: Regional Anesthesia.” A Practice of Anesthesia for Infants and Children, Elsevier, Philadelphia, PA, 2019.
    5. Frenkel O, Mansour K, Fischer JW. Ultrasound-guided femoral nerve block for pain control in an infant with a femur fracture due to nonaccidental trauma. Pediatr Emerg Care. 2012 Feb;28(2):183-4. PMID 22307191
    6. Heffler MA, Brant JA, Singh A, et al. Ultrasound-Guided Regional Anesthesia of the Femoral Nerve in the Pediatric Emergency Department [published online ahead of print, 2022 Jan 10]. Pediatr Emerg Care. PMID 35245015
    7. Lam-Antoniades M, Ratnapalan S, Tait G. Electronic continuing education in the health professions: an update on evidence from RCTs. J Contin Educ Health Prof. 2009;29(1):44-51. PMID 19288566
    8. Lin-Martore M, Olvera MP, Kornblith AE, et al. Evaluating a Web‐based Point‐of‐care Ultrasound Curriculum for the Diagnosis of Intussusception. Academic Education and Training. 2020 Sep 23;5(3):e10526. PMID 34041433
    9. Marin JR, Lewiss RE, American Academy of Pediatrics CoPEM, et al. Point-of-care ultrasonography by pediatric emergency physicians. Policy statement. Ann Emerg Med. 2015;65(4):472-478. PMID 25805037
    10. Neubrand TL, Roswell K, Deakyne S, Kocher K, Wathen J. Fascia iliaca compartment nerve block versus systemic pain control for acute femur fractures in the pediatric emergency department. Pediatr Emerg Care. 2014 Jul;30(7):469-73. PMID 24977991
    11. Thigh Arteries Schema. Wikimedia Commons, 23 July 2010. Accessed 17 Dec. 2021.
    12. Turner AL, Stevenson MD, Cross KP. Impact of ultrasound-guided femoral nerve blocks in the pediatric emergency department. Pediatr Emerg Care 2014 Apr;30(4):227-9. PMID 24651214
    13. Vieira RL, Hsu D, Nagler J, et al. Pediatric emergency medicine fellow training in ultrasound: consensus educational guidelines. Acad Emerg Med. 2013;20(3):300-6. PMID 23517263
    14. Wathen JE, Gao D, Merritt G, et al. A randomized controlled trial comparing a fascia iliaca compartment nerve block to a traditional systemic analgesic for femur fractures in a pediatric emergency department. Ann Emerg Med. 2007. ;50(2):162-171.e1. PMID 17210208
    By |2022-04-05T22:52:29-07:00Apr 6, 2022|Orthopedic, Pediatrics, PEM POCUS, Ultrasound|
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