What type of EKG changes may be seen following ingestion of this medication, often prescribed for an upper respiratory infection?
[Author’s own image]
Preschool wheezing is one of the most common pediatric ED presentations, and reaching for azithromycin can be tempting. Rhinovirus is the virus most often detected in these episodes, but pathogenic bacteria are commonly found in the nasopharynx of affected children, and some earlier outpatient data suggested that early antibiotic therapy might blunt severity.
The AZ-SWED trial (Azithromycin Therapy in Preschoolers with a Severe Wheezing Episode Diagnosed at the Emergency Department), published in the New England Journal of Medicine, tested this directly in the ED. The trial was stopped early for futility [1].
Denninghoff et al enrolled 840 children aged 18-59 months presenting with moderate-to-severe wheezing across eight PECARN emergency departments. The age range was chosen to target preschool-aged children before a clear asthma diagnosis is typically established, the population in whom antibiotic benefit has been most often hypothesized and in whom practice variation is greatest. Children were randomized to either a 5-day course of azithromycin or a matching placebo, with all participants also receiving standard care at the treating clinician’s discretion, including bronchodilators and corticosteroids.
Because prior research raised the possibility that bacterial co-colonization might identify a subgroup most likely to benefit from antibiotics [2-5], the trial pre-specified separate analyses for children with and without detectable nasopharyngeal Streptococcus pneumoniae, Moraxella catarrhalis, or Haemophilus influenzae, the three organisms most commonly implicated in respiratory illness in this age group. This let the investigators test whether the bacteria-positive children benefit, rather than leaving it as a post hoc question.
The primary outcome was symptom severity over 5 days, measured using the Asthma Flare-up Diary for Young Children (ADYC), a validated 17-item caregiver-reported instrument in which each symptom is scored from 1 (best) to 7 (worst) [6]. Secondary outcomes included ED and hospital length of stay and return ED visits or hospitalizations within 72 hours [1].
Azithromycin provided no clinical benefit over placebo, regardless of bacterial detection status.
ADYC symptom scores over 5 days were similar between groups in children with detectable nasopharyngeal bacteria (p = 0.70) and in those without (p = 0.69). There were no meaningful differences in length of stay or in return visits or hospitalizations.
Rhinovirus was the most commonly detected virus, identified in 72.5% of participants. Pathogenic bacteria were detected on nasopharyngeal swab in 62% of children overall. Azithromycin did clear nasopharyngeal bacteria more effectively than placebo (58.7% vs 11.4%), confirming that the drug was biologically active. That microbiologic effect, however, did not translate to clinical improvement on any outcome measured.
This is a large, ED-based randomized trial, and it argues against routine antibiotic use in preschool wheezing. Up to a quarter of children hospitalized for wheezing currently receive antibiotics, which likely reflects the same uncertainty the trial set out to address. The bacteria detected in the nasopharynx do not appear to drive the acute wheezing episode in these children, and treating them does not change how the children do.
The dissociation between bacterial clearance and clinical outcomes is itself informative. The fact that azithromycin reliably eradicated nasopharyngeal bacteria without any detectable clinical signal suggests that these organisms are bystanders rather than drivers of the acute episode, at least in most preschool wheezers. This has implications beyond this trial: it cautions against using bacterial detection alone as a rationale for antibiotic prescribing in this age group.
Routine azithromycin has no role in the management of preschool wheezing, even in children with detectable nasopharyngeal bacteria. Bronchodilators and corticosteroids where appropriate remain the mainstays of care, and these data give clinicians another reason to hold antibiotics in this group.
When people intentionally lick this toad, which toxin can they be exposed to?
[Image by Spencer B. via iNaturalist]
Read this tutorial on the use of point of care ultrasonography (POCUS) for pediatric musculoskeletal evaluation. Then test your skills on the ALiEMU course page to receive your PEM POCUS badge worth 2 hours of ALiEMU course credit.
A 13-year-old female with no past medical history presents to the emergency department with pain and swelling to her left knee. The pain started 3 days ago, with the pain worsening and swelling noted on the day prior to arrival. She can bear weight but has a limp. She has had no other current or past joint pain or swelling, no known trauma, no fever or other infectious symptoms, no recent travel, and no known insect or tick bites. She spent the summer at camp in the northeast United States. Her vaccines are up to date.
On arrival, her vital signs are:
| Vital Sign | Finding |
|---|---|
| Temperature | 37.3 C |
| Heart rate | 109 bpm |
| Blood pressure | 117/74 |
| Respiratory rate | 20 |
| Oxygen saturation (room air) | 99% |
On physical examination, she is well appearing and in no acute distress. Her exam is significant for left knee swelling and tenderness to palpation anteriorly with decreased knee flexion due to pain. She has no redness, warmth, or numbness around her knee. She has an antalgic gait but can bear weight.
Given her pain and swelling of her left knee, blood tests and X-rays are ordered, and orthopedics is consulted. You decide to perform a musculoskeletal point-of-care ultrasound (MSK POCUS) examination.
Note: This module focuses on diagnostic uses in musculoskeletal POCUS and not on procedural uses.
Figure 1. Linear ultrasound probe.
Figure 2. Linear probe with copious gel (L). The clinician floats the probe on the gel and rests the base of the scanning hand on an uninjured area to minimize pressure on the painful area (R).
To evaluate for fracture, dislocation, or osteomyelitis, place a linear transducer over the desired area to identify changes to the bony contour or alignment.
Figure 3. Water bath technique to image a phalanx dorsally (L) and ventrally (R), with the submerged probe floating just above but not touching the injured hand.
Figure 4. Normal finger phalanx imaged with the water bath technique, with the probe not touching the finger and approximately 1 cm of anechoic fluid between the probe and the finger. Air bubbles may be visible in the water.
Figure 5. Ultrasound clip of a normal finger phalanx using the water bath technique.
Normal bone is seen as a hyperechoic line with posterior acoustic shadowing.
Normal physis:
Figure 6L. Longitudinal view of a normal physis. The hypoechoic band of cartilage forms a smooth V-shape between the hyperechoic metaphysis and epiphysis (yellow arrows: physis above, bone below). Compare with the contralateral side to confirm symmetry. | Figure 6R. Longitudinal scanning of a normal physis. |
Figure 7L. Transverse view of a normal physis. The cartilage band appears regular but ragged between the curvilinear hyperechoic metaphysis and epiphysis (yellow arrows: physis above, bone below). | Figure 7R. Transverse scanning of a normal physis. |
Ultrasonography can reliably detect diaphyseal (long bone) fractures including the forearm, lower leg, and clavicle. It is also useful for detection of other fractures.
Figure 8L. Forearm fracture in longitudinal view. An angulated, displaced distal radius fracture is shown, with the physis visible distal to the fracture site. | Figure 8R. Longitudinal scanning of a distal radius fracture. |
Figure 9L. Forearm fracture in transverse view. The fracture site shows an irregular curvilinear bony surface with both edges of the fracture visible. | Figure 9R. Transverse scanning of a distal radius fracture. |
Figure 10L. Two examples of buckle fracture of the distal radius (arrows). Top: small “bump” in the bony cortex without discontinuity. Bottom: a second buckle fracture of the distal radius in longitudinal view. | Figure 10R. Buckle fracture of the distal radius. |
Figure 11. Discontinuity of the bony cortex of the phalanx (arrow) in a water bath, consistent with fracture. The adjacent joint is regular and intact.
Figure 12L. Longitudinal scanning of a phalanx fracture. | Figure 12R. Transverse scanning of a phalanx fracture. |
Figure 13L. Cortical discontinuity (arrow) in a metacarpal fracture, with periosteal fluid (asterisk) adjacent to the fracture site. | Figure 13R. Scanning of a metacarpal fracture. |
Figure 14. Linear probe positioning to evaluate for a nasal fracture.
Figure 15. Transverse view of a normal nasal bone (L) and a nasal fracture with cortical discontinuities (arrows, R).
Figure 16. Transverse scan of a nasal fracture.
Figure 17L. Healing distal radius fracture in longitudinal view, with periosteal thickening and callus formation. | Figure 17R. Longitudinal scan of a healing distal radius fracture. |
Figure 18L. Healing distal radius fracture in transverse view, with periosteal thickening and callus formation. | Figure 18R. Transverse scan of a healing distal radius fracture. |
For evaluation of a joint effusion, the linear or curvilinear transducer is used to identify anechoic or hypoechoic fluid in the joint space. POCUS identifies the effusion but cannot distinguish hemorrhagic, infectious, or inflammatory etiologies; labs and/or advanced imaging are needed for further work-up.
POCUS of the lower extremity can assess for hip, knee, or ankle effusions. Findings must be interpreted with the clinical presentation and physical examination. For hip effusions, the Kocher criteria may be used to evaluate for septic hip.
Figure 19. Linear probe positioning to evaluate for hip effusion (L) and normal hip anatomy (R). The arrow points to the femoral head physis.
Figure 20. Longitudinal scanning of a normal hip.
Figure 21. Hip effusion with anechoic fluid layering over the femoral neck measured to 5.7 mm. Also visible are the femoral head with an open physis (arrow) and the iliopsoas muscle (*).
Figure 22. Longitudinal scanning of the hip showing a hip effusion.
Figure 23. Linear probe positioning to evaluate for knee effusion. Note the towel under the knee for slight knee flexion (L). Normal knee anatomy showing the quadriceps tendon (arrows) and cartilage around the patella (asterisk) (R).
Figure 24. Normal bursae anatomy at the knee. The suprapatellar bursa is contiguous with the knee joint space [2].
Figure 25. Longitudinal scanning of a normal knee.
Figure 26. Two examples of a knee effusion with anechoic fluid (*) between the femur and the quadriceps tendon (L) and with measurement of effusion (R).
Figure 27. Longitudinal scanning of a knee effusion.
Figure 28. Ankle POCUS: Linear probe positioning to evaluate for ankle effusion (L) and normal ankle anatomy with an arrow pointing to the tibiotalar joint space (R).
Figure 29. Ankle POCUS of bilateral ankles showing an effusion (*) in the right tibiotalar joint compared with the normal left side.
Figure 30. Longitudinal scanning of an ankle effusion.
POCUS of the upper extremity can assess for elbow and shoulder effusions. When an elbow effusion is identified after trauma, radiography is typically needed to further characterize a fracture.
Figure 31. Linear probe positioning for performing POCUS of the elbow to evaluate the elbow posterior fat pad in longitudinal (L) and transverse (R) views.
Figure 32. Elbow POCUS: Normal elbow anatomy in longitudinal (L) and transverse (R) views with the posterior fat pad (PFP) located under the distal humeral line (dotted line).
Figure 33. Scanning of a normal elbow in longitudinal (L) and transverse (R) views.
Figure 34. Elevated posterior fat pad in longitudinal view rising above the distal humeral line (L) and transverse view rising above the line connecting both edges of the olecranon fossa (R). In both views, the posterior fat pad pushes up on the triceps muscle.
Figure 35. Scanning of an elbow effusion with an elevated posterior fat pad in longitudinal (L) and transverse (R) views.
Figure 36. Elbow POCUS: Elevated posterior fat pad with lipohemarthrosis (*) in longitudinal (L) and transverse (R) views.
Figure 37. Shoulder POCUS: Linear probe positioning to evaluate for shoulder effusion (L) and the corresponding ultrasound view with normal shoulder anatomy (R).
Figure 38. Shoulder POCUS: anechoic fluid (*) adjacent to the humeral head (L) and transverse scanning of the same effusion (R).
Figure 39. Transverse view of an anterior shoulder dislocation: humeral head dislocated anteriorly, or farther away from the probe (L) and corresponding transverse scanning (R).
Figure 40. Finger dislocation with probe positioned dorsally (L) and ventrally (R).
Figure 41. Scanning of a finger dislocation: dorsal view (L) and ventral view (R).
Figure 42. Osteomyelitis of the distal femur with irregular bony cortex and periosteal abscess (*) (L) and increased vascular flow adjacent to the periosteal abscess (R).
Figure 43. Scanning of a distal femur with osteomyelitis: longitudinal view (L) and transverse view (R).
Figure 44. Longitudinal scanning of a distal femur with osteomyelitis showing increased vascularity on color Doppler.
MSK POCUS is excellent for long-bone fractures but is less reliable for fractures at joints, epiphyses, and the small bones of the hands and feet, whose curved, irregular contours are more difficult to image. Non-displaced physeal fractures (Salter-Harris I) and fractures <1 mm may also be missed. POCUS generally focuses on the area of injury and does not image the entire bone, so distant pathology can be missed.
Additionally, for elbow evaluation, radial neck and medial epicondyle fractures are extra-capsular and may occur without an associated effusion. A normal posterior fat pad on POCUS does not exclude these fractures. If a patient has tenderness at the radial neck or medial epicondyle, obtain further imaging.
POCUS can identify the presence of pathology such as a joint effusion or bone infection, but it cannot determine the etiology (e.g., hemorrhagic vs. infectious vs. inflammatory effusion). Further work-up, such as labs, joint aspiration, or advanced imaging, is needed to characterize the underlying process.
Sharing POCUS clips within or between institutions can be cumbersome. Where feasible, archiving images to the medical record helps preserve diagnostic context for the broader healthcare team.
| Study | Application | N | Sensitivity | Specificity | Comments |
|---|---|---|---|---|---|
| Morello et al, Eur J Pediatr 2024 [3] | Distal forearm fractures | 23 studies, 3,484 children | 92–100% | 85–100% | Scoping review |
| Hassankhani et al, Skeletal Radiol 2024 [4] | Clavicle fractures | 7 studies, 1,255 patients | 94% | 98% | Pediatric subset (4 studies, 863 children): Sn 96%, Sp 94% |
| Zhao et al, Medicine 2019 [5] | Hand fractures | 7 studies, 842 patients | 91% | 96% | Fracture prevalence 39% |
| Tokarski et al, J Pediatr 2018 [6] | Elbow fractures | 6 studies, 512 children | 96% | 81% | Fracture prevalence 48% |
| Gottlieb et al, Am J Emerg Med 2019 [7] | Shoulder dislocation | 7 studies, 739 patients | 99% | 99% | Dislocation prevalence 41%; associated fracture: Sn 98%, Sp 99.8% |
Table 1. Key systematic reviews and meta-analyses on musculoskeletal POCUS.
Other notable studies focusing on musculoskeletal POCUS include the following.
The BUCKLED multicenter, noninferiority, randomized trial by Snelling et al enrolled 262 children ages 5–15 years with clinically non-angulated distal forearm injuries [8]. Children were randomized to POCUS or radiography. Those in the POCUS group with a cortical break identified also received radiography and usual care; buckle fractures were managed with a splint.
Results: At 4 weeks, physical function of the affected arm was non-inferior in the POCUS group. The POCUS group also had fewer X-rays, shorter emergency department length of stay, and higher patient satisfaction. The authors emphasized that physical function at 4 weeks is an important, real-world clinical outcome.
Adhikari and Blaivas compared POCUS with physical examination for the diagnosis of joint effusions [9]. They enrolled 54 adult patients with joint pain, erythema, and swelling.
Results: POCUS was more sensitive and accurate than physical examination. POCUS altered emergency department management in 65% of patients, either by avoiding an unnecessary joint aspiration or by identifying a clinically occult effusion.
Jones et al conducted a multicenter prospective diagnostic study in children <18 years requiring radiology-performed hip ultrasound, comparing hip POCUS with the radiology study as the reference standard [10]. 161 children were enrolled by 18 PEM physicians, with 3 high-volume operators contributing 62% of cases.
Results: POCUS had an overall sensitivity of 94% and specificity of 98%. Among high-volume operators, sensitivity was 98% (specificity 98%); among low-volume operators, sensitivity was 83% (specificity 97%).
A musculoskeletal POCUS of the left knee with a linear, high-frequency probe demonstrated a joint effusion in the suprapatellar bursa with internal septations (Figures 45 and 46).
Figure 45. Left knee POCUS demonstrating a joint effusion in the suprapatellar bursa (L) and internal septations within the effusion (R).
Figure 46. Longitudinal scan of the left knee showing the joint effusion with internal septations.
Initial laboratory studies showed a white blood cell count of 10 × 109/L, ESR 69 mm/hr, and CRP 32 mg/L. Knee radiographs were negative for fracture. Orthopedics performed an arthrocentesis that yielded synovial fluid with 52,000 white blood cells/µL, raising concern for septic arthritis.
The patient was admitted, started on intravenous antibiotics, and taken to the operating room for incision, drainage, and washout. Joint fluid cultures returned negative, but Lyme serologies returned positive. She was transitioned to a 28-day course of doxycycline for Lyme arthritis.
Read this tutorial on the use of point of care ultrasonography (POCUS) for pediatric first-trimester pregnancy evaluation. Then test your skills on the ALiEMU course page to receive your PEM POCUS badge worth 2 hours of ALiEMU course credit.
A 17-year-old female with a past medical history of pelvic inflammatory disease, presents as a walk-in from triage with lower abdominal pain and vaginal bleeding that started this morning. She has soaked through three pads since this morning without the passage of clots. She reports mild nausea, and dizziness. She denies any fevers, chills, chest pain, shortness of breath, vomiting, or decreased appetite. She is currently sexually active with one male partner in a monogamous relationship and does not use protection. Her menstrual periods are irregular and she is unsure of her last menstrual period.
On arrival, her vital signs are:
| Vital Sign | Finding |
|---|---|
| Temperature | 37 C |
| Heart rate | 94 bpm |
| Blood pressure | 98/62 |
| Respiratory rate | 14 |
| Oxygen saturation (room air) | 99% |
An obstetric POCUS can be performed using both the curvilinear (transabdominal approach) and endocavitary probes (transvaginal approach). Certain anatomical structures such as the ovaries and an early pregnancy can be visualized earlier and with greater detail using an endocavitary probe due to its closer proximity to the area of interest. While earlier pregnancies may be identified by the transvaginal approach, we recommend starting with the transabdominal probe because it is less invasive. The transabdominal examination is best performed with a full bladder and the endocavitary examination is best performed with an empty bladder. Longitudinal and transverse views of the uterus should be obtained when using either the transabdominal or endocavitary probe.
Figure 1. Different probes used for first-trimester pregnancy ultrasound
Figure 2. Positioning for transabdominal approach
Figure 3. Normal transverse view of the uterus and bladder using the transabdominal probe. Image courtesy of The Pocus Atlas and Drs. Lindsay Davis and Hannah Koplinski
Figure 4. Normal longitudinal (sagittal) view of an anteverted uterus and bladder using the transabdominal probe. Image courtesy of The Pocus Atlas and Drs. Lindsay Davis and Hannah Koplinski
Not all institutions have access to an endocavitary probe. However, if your institution does, the transvaginal ultrasound examination can provide additional views of the uterus and surrounding structures.
Figure 5a. Positioning of endocavitary probe in transvaginal approach using a simulation model
Figure 5b. Indicator labeled on endocavitary probe
Key Point: To definitively diagnose an intrauterine pregnancy, either a yolk sac or fetal pole must be visualized within the gestation sac of the uterus.
There are many conflicting opinions about the upper limits of the discriminatory zone (B-hCG level at which an embryo is expected to be seen). In general, for a patient with a positive B-hCG with concern for an ectopic pregnancy, an ultrasound should be performed. Typically, a pregnancy should be visible by transvaginal ultrasound examination with a B-hCG of 1000-2000 mIU/mL and by transabdominal ultrasound examination at 6000-6500 mIU/mL [1, 2].
Figure 6. Double decidual sac sign in a normal intrauterine pregnancy
Figure 7. Fetal pole and yolk sac in a normal intrauterine pregnancy
In these sonographic images, there are several characteristic sonographic features of a normal first-trimester IUP. To definitively diagnose an intrauterine pregnancy, either a yolk sac or fetal pole must be visualized within the gestation sac of the uterus.
Once the embryo is identified, a fetal heart rate (FHR) can be obtained as early as 6 weeks of gestation. The fetal heart movement may be visualized as a flicker of movement. Visualization can be performed using either the endocavitary or curvilinear probe and the M-mode function. In POCUS, we do not use Doppler as this has a theoretical risk to the fetus.
To calculate the FHR, follow the following steps:
A normal FHR usually ranges from 110-160 beats per minute. It begins around 90–110 bpm and increases to 170 bpm by 9 weeks of estimated gestational age.
Figure 8. Fetal heart rate measurement (rate of 148 bpm) using M-mode
The most accurate time to estimate gestational age is during the first trimester. Accurate estimation of gestational age is crucial for guiding prenatal care, decision making in high-risk pregnancies, and establishing a reliable due date. This can be performed by either measuring mean sac diameter (MSD) or crown-rump length (CRL).
The MSD is the earliest measurement that can be used to estimate gestational age. This measurement is, however, less accurate than using crown-rump length and is typically performed between 5-8 weeks of gestation using the following steps:
Most ultrasound machines should help you perform this calculation; however, the gestational age can be calculated manually using the following formula: [4]
Gestational Age (days) = MSD (mm) + 30
Once an embryo is present in the gestational sac, CRL can be measured. CRL is the most accurate single measurement and is typically used to estimate gestational age between 6-13 weeks of gestation [4]. This measurement can be performed using the following steps:
Most ultrasound machines should help you perform this calculation. There are also available calculators (e.g. perinatology.com CRL calculator).
Figure 9. Crown rump length measurement showing an estimated fetal age of 6 weeks and 3 days
An ectopic pregnancy is a pregnancy in which a fertilized egg implants and grows outside the uterine cavity. The most common site for an ectopic pregnancy is the ampulla of the fallopian tube. The primary goal of performing an obstetric ultrasound in a pregnant patient who presents with abdominal pain, pelvic pain, and vaginal bleeding is not to rule in an ectopic pregnancy, but rather to rule in an IUP.
Ruling in an IUP essentially rules out an ectopic pregnancy, given that the incidence of a heterotopic pregnancy – the simultaneous occurrence of an intrauterine and an ectopic pregnancy – is 1 in 30,000. The rate of heterotopic pregnancies, however, rises significantly in patients who have undergone in-vitro fertilization (IVF) to ranges from 1 in 100 to 1 in 500 pregnancies [5]. A history of pelvic inflammatory disease also increases concern for heterotopic and ectopic pregnancy.
If an empty uterus is visualized on bedside ultrasound in a patient (as shown below) with a B-hCG level greater than the discriminatory zone, the next step is to examine the adnexa for sonographic signs of an ectopic pregnancy. However, the lack of a visualized IUP on POCUS in a pregnant patient is concerning for ectopic pregnancy, and it is not expected to be able to visualize the actual ectopic pregnancy.
Video 1. Coronal (transverse) view of uterus without an intrauterine pregnancy
Video 2. Sagittal (longitudinal) view of uterus without an intrauterine pregnancy
To examine the adnexa in the transabdominal view, ensure that the patient has a full bladder and identify the uterus in the sagittal and transverse views. Using the uterus as a landmark, sweep laterally and posteriorly at which point the ovaries may or may not be visualized. Use color Doppler to help distinguish the ovary (which has a vascular hilum) from surrounding structures. Sonographic signs of an ectopic pregnancy include:
A thick hyperechoic ring around a hypoechoic tubal mass
Video 3. Coronal (transverse) view of uterus showing tubal ring sign
A well-circumscribed hypoechoic structure surrounded by a hypervascular ring seen on color Doppler due to trophoblastic activity and neovascularization. Note that the ring of fire sign is also present in corpus luteum cysts, which are a type of functional ovarian cyst that forms after ovulation to support a possible pregnancy.
Figure 10. Ring of fire of the adnexa
If there is high suspicion for an ectopic pregnancy, assess for free fluid in the pelvis and abdomen, especially in the posterior cul-de-sac (pouch of Douglas) and hepatorenal recess (Morison’s pouch). The hepatorenal view is key for detecting hemoperitoneum in the supine patient. Fluid will often collect in Morison’s pouch first. Sweep through the pelvis in both sagittal and transverse planes to look for anechoic or hypoechoic fluid. While trace fluid may be normal in patients, the presence of moderate to large amounts of free fluid, particularly if echogenic (suggesting hemoperitoneum), raises concern for ruptured ectopic pregnancy and warrants immediate intervention. Ultimately, if the bedside ultrasound is inconclusive in a patient with clinical concern for ectopic pregnancy, a radiology performed ultrasound and/or gynecology consult should be ordered urgently.
Figure 11. Free fluid collecting in the right upper quadrant hepatorenal recess (Morison’s pouch)
Uterine fibroids, also known as leiomyomas or myomas, are benign smooth muscle tumors of the uterus. On ultrasound, they typically appear as well-circumscribed, hypoechoic (relative to the myometrium) structures that can arise within the myometrium (intramural), along the outer surface of the uterus (subserosal), project into the endometrial cavity (submucosal), and can be attached by a stalk (pedunculated).
Figure 12. Uterine fibroids
A molar pregnancy, also called a hydatidiform mole, is a type of gestational trophoblastic disease that results from abnormal fertilization, leading to the growth of abnormal trophoblastic tissue rather than a normal embryo.
A complete mole, which occurs due to fertilization of an empty ovum by one (or two) sperm, typically has a “snowstorm” or “cluster of grapes” appearance. On ultrasound, the uterus may appear larger than expected for gestational age and may show a diffusely echogenic intrauterine mass with numerous cystic spaces.
Figure 13. Molar pregnancy
An ovarian cyst is a fluid-filled sac within or on the surface of the ovary. Most are benign and functional, especially in reproductive-age women, and often resolve spontaneously.
On ultrasound, simple ovarian cysts appear as a thin, smooth-walled anechoic structure. A corpus luteum cyst, which may have a “ring of fire” appearance on color Doppler, is more thick-walled in appearance. Hemorrhagic cysts tend to have mixed echogenicity with a lacy, reticular pattern.
Figure 14. Ovarian cysts
Ovarian torsion is often on the differential for female patients presenting with sudden onset lower abdominal pain. It is a gynecologic emergency where the ovary twists on its own vascular pedicle, compromising blood flow. Patients with large ovarian cysts or masses ≥5cm are at increased risk.
On ultrasound, an enlarged, edematous ovary with absent or decreased flow may suggest this diagnosis. The ovary also tends to have peripheralized follicles. A midline ovary can also be a concerning sign. Venous flow is typically lost prior to arterial flow; however, presence of flow does not rule out ovarian torsion. Lastly, a highly specific finding for ovarian torsion may be the presence of a whirlpool sign which is visualized as a targetoid, coiled structure on color Doppler.
Figure 15. Ovarian torsion with midline, edematous ovary
Integration of the obstetric POCUS into early pregnancy assessment can significantly accelerate diagnosis and initiation of treatment, particularly in urgent cases like an ectopic pregnancy. Faster timelines could translate into improved clinical outcomes and more efficient ED workflows.
Studies that helped shape the landscape for the utility of POCUS in early pregnancy in the emergency department setting include:
| Study | Study Type, Location (Time frame) | N, Ages | Notes |
|---|---|---|---|
| Doubilet et al., N Engl J Med. 2013 [6] | Review Article | N/A | This review establishes more stringent ultrasound criteria for diagnosing early pregnancy failure to minimize false-positive results:
These guidelines are designed to protect viable pregnancies from premature or inappropriate interventions. |
| Thamburaj et al. Pediatr Emerg Care. 2013 [7] | Retrospective case-cohort review, Single ED at Newark Beth Israel Medical Center (2007) | 330 Female patients aged 13-21 Bedside POCUS group (n = 244, ~74%; Radiology group (n = 86) | Time-to-scan: 82 min vs. 149 min (POCUS vs. radiology), P < 0.001 LOS: 142 min vs. 230 min (P < 0.001) Despite similar demographics, chief complaints, diagnoses, and dispositions between groups, bedside ultrasound significantly reduced both scan time and overall ED stay. |
| McRae et al. CJEM. 2009 [8] | Systematic review, multiple EDs including international data | N/A | ED-targeted ultrasound is highly specific and reliably identifies IUP. The specificity for detecting IUP exceeded 98% in most studies, and sensitivity typically above 90%. Bedside ultrasound reduced missed ectopic diagnosis, decreased time to surgical treatment for ectopic cases, shortened ED lengths of stay in normal pregnancies, and showed greater cost-effectiveness versus formal radiology ultrasound. |
| Durston et al. Am J Emerg Med. 2000 [9] | Retrospective cohort, single-center (1992-1998) | 120 patients diagnosed with ectopic pregnancy | Compared 3 different ultrasound availability models over sequential time periods:
Increasing ED ultrasound availability improved the quality of ectopic pregnancy detection. The combined approach of initial ED physician bedside ultrasound followed by formal imaging when indicated was the most cost-effective and efficient. |
| Mateer et al. Acad Emerg Med. 1995 [10] | Prospective cohort, single-center | 148 pregnant women at risk for ectopic pregnancy | Emergency physicians trained in bedside transvaginal ultrasound (TVUS) demonstrated a 93% agreement rate with gynecologists in interpreting scans. Most ectopic pregnancies were identified early, allowing prompt management. Established feasibility and high accuracy of ED physician-performed POCUS for early pregnancy evaluation, promoting wider adoption in emergency care. |
| Beals et al. Am J Emerg Med. 2019 [11] | Systematic review, multi-center | 2,350 patients across 6 studies | Patients who received POCUS had a mean reduction in ED LOS of 73.8 minutes (95% CI: 49.1–98.6) compared to those who underwent comprehensive ultrasound. All included studies reported decreased LOS with POCUS. |
You use a curvilinear abdominal probe (Figure 16) and endocavitary probe (Figure 17) and visualize the following:
Figure 16. Right adnexal view showing a “ring of fire” sign suggestive of an ectopic pregnancy
Figure 17. Sagittal view of uterus showing the absence of an intrauterine pregnancy
Given her initial low blood pressure and an obstetric ultrasound concerning for an ectopic pregnancy, you decide to perform a FAST exam, and you see free fluid in the hepatorenal recess.
Figure 18. Right upper quadrant abdominal view, showing free fluid in Morison’s pouch
Serum labs show the following:
The obstetrics and gynecology team is consulted for a likely ectopic pregnancy, and the patient is taken to the OR for an emergent laparotomy.
Ingestion of the pictured mushroom is most associated with which toxicity?
[Image credit to William Morris via Creative Commons]
(more…)
For years, clinicians and researchers have debated a fundamental question in pediatric emergency care: does the type of fluid used in pediatric sepsis resuscitation matter?
The PRoMPT BOLUS trial was designed to answer this question. Conducted across 47 international sites in 5 countries and enrolling more than 9,000 children, this large, pragmatic randomized trial compared 0.9% saline with balanced crystalloids in children treated for suspected septic shock.
The results have just been released. Across a wide range of clinically meaningful outcomes (including kidney injury, mortality, and recovery), there was no difference between fluid types.
Sepsis remains a major global health concern, affecting approximately 50 million people each year, with children accounting for nearly half of these cases. Early fluid resuscitation is a cornerstone of treatment, making the choice of fluid a critical and historically debated decision.
Two primary types of crystalloid fluids are used in practice:
Prior research raised concerns that saline could contribute to metabolic acidosis and kidney injury, while balanced fluids were associated with improved outcomes in some adult and smaller pediatric studies. However, the pediatric literature remained inconsistent, with observational studies reaching conflicting conclusions. As a result, guidelines offered only weak recommendations favoring balanced fluids and called for more definitive trials.
PRoMPT BOLUS was designed to fill this gap.
This trial used a pragmatic, randomized design (NS vs. balanced fluids), intentionally embedded into routine clinical care. Pragmatic trials evaluate clinical interventions within typical practice, rather than highly controlled clinical settings. By incorporating fluid randomization without modifying additional aspects of clinical practice, this approach allowed investigators to study fluid choice in real-world conditions across diverse healthcare systems. PRoMPT BOLUS was a collaborative effort across multiple networks including PECARN (Pediatric Emergency Care Applied Research Network), PERC (Pediatric Emergency Research Canada), and PREDICT (Paediatric Research in Emergency Departments International Collaborative).
Children ages 2 months to <18 years were eligible if clinicians suspected sepsis and were planning to treat with more than one fluid bolus for abnormal perfusion consistent with septic shock. They were randomized to receive either balanced fluids or 0.9% saline, with clinicians otherwise managing care as they normally would.
The primary outcome was MAKE30 (Major Adverse Kidney Events within 30 days), a composite that includes mortality, need for renal replacement therapy, or persistent kidney dysfunction at hospital discharge or 30 days, whichever came first.
This pragmatic approach was critical to the study’s success. It allowed for:
The primary outcome, MAKE30, occurred at nearly identical rates in both groups:
This difference was neither statistically nor clinically significant. There were also no differences in any of the individual MAKE30 components between treatment groups.
Similarly, there were no meaningful differences in:
Together, these findings strongly support the conclusion that both fluids are equally safe and effective.
Although there were measurable and statistically significant biochemical differences between groups (such as higher rates of hyperchloremia and hypernatremia with saline and hyperlactatemia with balanced fluids), these changes did not translate into clinically meaningful outcomes.
Subgroup analyses across patient characteristics, illness severity, and total fluid volume showed no differences in outcomes. While there was a non-significant trend suggesting potential benefit of balanced fluids in the most severely ill patients, the study was not powered to confirm this finding.
The results of PRoMPT BOLUS can be distilled into several key conclusions:
Importantly, while the study cannot fully exclude a benefit of balanced fluids in the sickest patients, it provides strong evidence that for children presenting to the ED with suspected sepsis, either fluid is an appropriate choice.
These findings have immediate and meaningful implications for clinical practice.
First, they simplify decision-making. Clinicians can focus on timely recognition and treatment of children with suspected sepsis, and engage in fluid resuscitation with fluids that make sense for the clinical scenario.
Second, the results support flexibility in care. Fluid choice can now be guided by:
While the study is robust, several limitations should be considered.
The overall incidence of MAKE30 was lower than expected (~3% vs. an anticipated ~6%), which may reflect a less severely ill population than initially projected. This could limit the ability to detect small differences between groups.
Additionally, although subgroup analyses suggested a possible benefit of balanced fluids in more severely ill patients, the study was not powered to draw definitive conclusions in this population.
The PRoMPT BOLUS trial provides the strongest evidence to date addressing fluid choice in children presenting to the ED with suspected sepsis. Both 0.9% saline and balanced crystalloids are safe and effective for resuscitation in children with suspected septic shock.
