EM ReSCu Peds 16: Supraventricular Tachycardia

Brief Narrative Description of Case

A 6-month-old girl is brought in by parents for poor feeding. She is in compensated supraventricular tachycardia (SVT) on initial exam. Learners will initiate initial assessment by obtaining history and performing physical. SVT will be identified on cardiac monitoring and/or ECG. SVT will be unresponsive to vagal maneuvers and adenosine. 10 minutes into the case, the patient will decompensate and require bag mask ventilation (BMV) and electrical cardioversion, which will succeed in converting the patient into sinus rhythm. Learners will then identify a disposition plan for the patient.

Primary Learning Objectives

At the end of this simulation, participants should be able to:

  1. Demonstrate early evaluation of a critically ill patient (application)
  2. Describe signs/symptoms of SVT in an infant (comprehension)
  3. Differentiate compensated from decompensated shock in an infant (analysis)
  4. Demonstrate physiologic (vagal), pharmacologic, and electrical cardioversion for SVT (application)
  5. Demonstrate BMV in an infant (application)
  6. Demonstrate focused history taking from a caregiver (application)
  7. Explain diagnosis and management to caregivers (synthesis)
  8. Demonstrate teamwork and closed loop communication (application)

Critical Actions

  • Assign/assume team roles
  • Obtain history from parent
  • Perform primary assessment
  • Administer supplemental oxygen
  • Place patient on continuous cardiac monitor
  • Obtain vascular access
  • Perform focused physical exam
  • Verbalize recognition of SVT from ECG and/or monitor
  • Perform vagal maneuver (ice pack to face, rectal stimulation via thermometer insertion, knees to chest)
  • Administer adenosine in appropriate dose(s) (0.1-0.2 mg/kg IV) with rapid flush
  • Apply defibrillator pads to patient
  • Support oxygenation and ventilation by bag-mask ventilation (BMV)
  • Perform synchronized electrical cardioversion
  • Explain diagnosis to parent and how it relates to the patient presentation

Case Creators


  • Rebekah Burns, MD
  • Marc Auerbach, MD, MSc, FAAP


  • Michael Nguyen, MD, FACEP
  • Moon Lee, MD, MPH
  • Sara Skarbek-Borowska, MD

Updated August 18, 2020

Go to Next Tab – Setup


Chief complaint: Poor feeding
Patient age: 6 month old
Weight: 7 kg

Recommended Supplies

  • Manikin: Infant (e.g., Laerdal SimBaby or Gaumard Newborn PEDI)
  • Moulage: None
  • Resources: Pediatric Advanced Life Support (PALS) cards and/or weight-based tape (e.g., Broselow Tape)
  • Manikin set up: Intravenous (IV) line x 1 in place with drainage bag
  • Equipment:
    • Defibrillator with snaps for simulator or pediatric defibrillator pads
    • Pediatric airway equipment of various sizes/airway cart
      • Simple facemask
      • Non-rebreather mask
      • Nasal cannula
      • Oxygen tubing
      • Bag valve mask (self-inflating bag with infant mask)
      • Suction
      • Optional: Intubation supplies (laryngoscope, end tidal CO2, endotracheal (ET) tube, laryngeal mask airway (LMA) or Intersurgical i-gel®, stylet, tape)
    • 3-way stop cock
    • Syringes
    • Ice pack
  • Medications: Adenosine, midazolam or lorazepam, fentanyl or morphine, epinephrine, normal saline bag, normal saline flush, optional intubation medications (rocuronium, succinylcholine, atropine, ketamine, propofol, etomidate)

Supporting Files

  • Initial ECG (supraventricular tachycardia)
  • Post-cardioversion ECG (sinus rhythm)
  • Chest x-ray post conversion (normal)
  • Chest x-ray after intubation (optional Stage 3)
  • Point-of-care labs


  • Participants/learners:
    • Team leader
    • Airway manager
    • Survey physician
    • Medication preparer
    • Medication giver
    • Family liaison/history taker
  • Other:
    • Faculty or other embedded participants can play a nurse, respiratory therapist, or tech, if there are not enough
      learners to perform the above roles
    • Standardized patient (actor or faculty) to play patient’s parent

Team roles may need to be adjusted in order to suit local practices and norms

Prerequisite Knowledge

  • Faculty
    • PALS protocols
    • General knowledge of emergency medicine
    • Simulation implementation and debriefing experience
  • Emergency medicine residents
    • Any stage of training (preferably PGY-1 or PGY-2)
    • Completed PALS certification

Case Alternatives

  • Have learners apply defibrillator pads, charge, and deliver shock even if these roles are usually performed by a different team member.
  • If residents attempt intubation during the case, the patient loses pulses and the team must administer CPR for 2 minutes and one dose of IV epinephrine before rhythm returns to unstable SVT.
  • If an unsynchronized shock is delivered while the patient is in SVT, the rhythm converts to ventricular fibrillation (VF). Chest compressions must be started and the patient converts to sinus tachycardia after defibrillation with 2 J/kg.

Virtual Resus Room

This simulation case can be run virtually using Google Slides and Zoom from the Virtual Resus Room (Infant SVT) page.


PC1. Emergency Stabilization
PC2. Performance of Focused History & Physical Exam
PC3. Diagnostic Studies
PC5. Pharmacotherapy
PC9. General Approach to Procedures
PC10. Airway Management
PC14. Vascular Access
ICS1. Patient Centered Communication
ICS2. Team Management


  1. de Caen AR, Berg MD, Chameides L, et al. Part 12: Pediatric Advanced Life Support: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2015;132(18 Suppl 2):S526-42. PMID: 26473000
  2. Chang PM, Silka MJ, Moromisato DY, Bar-Cohen Y. Amiodarone versus procainamide for the acute treatment of recurrent supraventricular tachycardia in pediatric patients. Circ Arrhythm Electrophysiol. 2010;3:134-40. PMID: 20194798
Go to Next Tab – Presentation
Overall Appearance6-month-old female alert, but crying and fussy
HPIPatient arrives by private vehicle accompanied by a parent. “She does not want to take her formula for the past 8 hours”
If the learners ask for specifics:
 She seems hungry, but then stops drinking her formula after she has had about one ounce. Before today, she took about 4-6 ounces every 3 hours. The patient is bottle-fed and has been on Enfamil formula since birth.ROS: Fatigue, fussiness, and sweating with attempted feeding. No fevers, cough, emesis, diarrhea or rashes.
Past Medical/Surgical History
  • Prior history of admission for bronchiolitis at 2 months of age.
  • Born at 37-weeks gestation. Unremarkable gestation and delivery.
AllergiesNo known drug allergies
Family HistoryUnremarkable
Social HistoryNo pets. No smokers. Attends daycare.
Go to Next Tab – Stage 1

Compensated SVT

Start through second dose of adenosine OR 10 minutes into case

Critical Actions

  • Team leader assigns tasks
  • Obtain history from parent
  • Perform primary survey
  • Administer supplemental oxygen
  • Place patient on continuous cardiac monitor
  • Obtain vascular access
  • Perform focused physical exam
  • Verbalize recognition of SVT from ECG and/or monitor
  • Verbalize stable vs unstable SVT appropriately
  • Perform vagal maneuver (ice pack to face, rectal stimulation by thermometer insertion, knees to chest)
  • Administer normal saline bolus at 5-10 mL/kg
  • Discuss progress and plan of care with the parent (and involve them in decision-making)
  • Administer adenosine (0.1-0.2 mg/kg IV, rapid push with immediate flush for first dose; 0.2 mg/kg for subsequent doses)
  • Apply defibrillator pads to patient (should be in place prior to performing vagal maneuvers or administering adenosine)

Unbolded items may be excluded depending on local practices and norms.

Physical Exam

Vital SignsT: 37.5°C, HR: 280, BP: 100/70, RR: 50, SpO2: 96%, Wt: 7 kg
GeneralAlert, crying, tachypneic
LungsClear to auscultation bilaterally
CardiovascularTachycardic, no abnormal heart sounds, strong pulses, capillary refill 4 seconds
AbdomenNormal, liver edge palpated just below costal margin
NeurologicalFussy but alert; moves all extremities
SkinDiaphoretic, mottled
Other Relevant SystemNo edema

Instructor Notes: Changes and Case Branch Points

Team attempts IV lineFaculty/nurse verbalizes that the attempt is successful.
Supplemental oxygen providedSpO2 = 100%
Treatment initiated without discussing with the parentParent asks, “Why does this have to be done?” Parent will be satisfied with a direct/accurate explanation.
Vagal maneuver attempted such as ice pack administered to patient’s face (without obscuring the mouth or nose), performing rectal stimulation via thermometer insertion, or placing knees to chestNo change in cardiac rhythmPatient tolerates procedure
Adenosine administered (each dose)No change in cardiac rhythm or (optional) very transient change in heart rate that returns to 280. Brief flat line after administration with resumption of SVT.Prior to administration, faculty/nurse will ask for clarification on how the medication should be given
Gradually over the first 10 minutes of the case OR after second dose of adenosine (0.2 mg/kg)Proceed to Stage 2.
Go to Next Tab – Stage 2

Decompensated SVT

10 minutes from the start of the case (or after second dose of adenosine) through cardioversion at 1 J/kg

Critical Actions

  • Verbalize decompensated state
  • Support airway by BMV
  • Perform synchronized electrical cardioversion

Physical Exam

Vital SignsHR: 280, BP: 60/38, RR: 4, SpO2: 80%
Exam Changes
  •  The patient becomes unresponsive. Notably, she stops crying.
  • Central pulses 1+
  • Shallow, infrequent respirations
  • Capillary refill 5 seconds

Instructor Notes: Changes and Case Branch Points

In this stage, the patient fails to improve with first-line medications.

Learners do not recognize decompensated state or change in mental statusNurse or parent says, “What happened? She’s not responding?”
Learners do not recognize poor inspiratory effortNurse says, “Her respirations are really shallow and it seems her respiratory rate has decreased.”
BMV started with appropriate seal and rateSpO2 = 96% but patient over-breathing bagging
Learners attempt to intubate rather than cardiovertIf they proceed with intubation, the patient rapidly develops bradycardia to 50. This then progresses to PEA, requiring CPR and 1 dose of IV epinephrine (0.01 mg/kg) before ROSC.Nurse states, “I am worried the patient will further decompensate if we don’t cardiovert her as quickly as possible.”
10-20 mL/kg isotonic bolus givenCapillary refill improves to 4 seconds. Crackles develop at the lung bases. No changes in SpO2.
30-40 mL/kg isotonic fluid givenCapillary refill improves to 4 seconds. Crackles develop at the lung bases. SpO2 decreases to 92% with supplemental oxygen.
50-60 mL/kg of isotonic fluid givenSpO2 decreases to 85%, diffuse crackles, liver palpated at 2 cm below costal margin.
Synchronized cardioversion at 0.5 J/kgNo change in cardiac rhythm
Synchronized cardioversion at 1 J/kgConversion to sinus rhythm. Proceed to Stage 4.

If learners are PGY-3 or PGY-4, the rhythm is sinus rhythm for a few seconds and then converts back to SVT (no matter how many cardioversion attempts are done).

If there are more than 3 cardioversion attempts at (1 J/kg), the rhythm changes to VF and the patient loses pulses.

If learners are PGY-3 or PGY- 4 go to optional Stage 3.

Learners must start chest compressions at a ratio of 15:2 and defibrillate with 2 J/kg before return to sinus tachycardia for a few seconds and then back to SVT.

Pain medication and/or sedative provided before cardioversionNo change in case
Delivery of unsynchronized shockRhythm changes to VF, and the patient loses pulses.Learners must start chest compressions at a ratio of 15:2 and defibrillate with 2 J/kg before return to sinus tachycardia, then go to Stage 4.

If learners are PGY-3 or PGY-4, the rhythm reverts to SVT. Go to optional Stage 3.

Go to Next Tab – Stage 3

Refractory SVT (optional)

After cardioversion at 1 J/kg through administration of amiodarone or procainamide

Critical Actions

  • Verbalize cardioversion is not working (refractory SVT)
  • Support airway by BMV or intubation at this stage
  • Management of SVT with anti-arrhythmic medications

Physical Exam

Vital Signs
(with BMV in Stage 2)
HR: 280, BP: 60/40, RR: 4, SpO2: 80%
Vital Signs
(without BMV in Stage 2)
HR: 280, BP: 72/40, RR: 30 (or bagged rate), SpO2: 80%
Exam ChangesSame as Stage 2:

  • The patient is unresponsive.
  • Central pulses 1+
  • Shallow, infrequent respirations
  • Capillary refill 5 seconds

Instructor Notes: Changes and Case Branch Points

BMV started with appropriate seal and rateSpO2 = 96%
Learners intubate patient with RSISpO2 = 99%If intubation is successful
Learners intubate patient without RSIPt gags, and the nurse states, “The child just had a large emesis.”
Synchronized cardioversion at 0.5-2 J/kgFew seconds of sinus rhythm (HR 160’s), then goes back to SVT
Learners do not recognize cardioversion is not workingNurse says, “It doesn’t seem like the shocks are working.”
Amiodarone or procainamide administeredConverts to sinus rhythm. Proceed to Stage 4.
Go to Next Tab – Stage 4

Case Conclusion

After cardioversion with 1 J/kg OR administration of amiodarone or procainamide

Critical Actions

  • Obtain post-conversion ECG and POC/baseline labs (if not already done)
  • Verbalize recognition of sinus rhythm
  • Explain diagnosis to parent and how it relates to the patient
  • Consult pediatric cardiology
  • Notify admission team/arrange for transfer

* Unbolded items may be excluded depending on local practices and norms

Physical Exam

Vital SignsHR: 160, BP: 80/52, RR: 40, SpO2: 100%
Exam Changes
  • Crying and responsive
  • Pulses 2+
  • Capillary refill 3 seconds
Go to Next Tab – Debrief

Demonstrate early evaluation of a critically ill patient (application)

Learners should approach a critically ill patient in a standardized fashion. Airway, breathing, and circulation should be assessed immediately. Interventions such as airway repositioning/adjuncts, BMV, and CPR should be started concurrently, if required. After A, B, C have been addressed, the patient should be evaluated for disability and exposed for a thorough head-to-toe exam. In pediatrics, people often say that D also stands for “don’t forget the dextrose” as a blood glucose level should be checked in any child with altered mental status.

Describe signs/symptoms of SVT in an infant (comprehension)

Unlike adults and older children, infants are unable to report a sensation of their heart racing. Instead, caregivers and providers must rely on other non-specific signs and symptoms. Infants’ hearts may tolerate the rapid rate for many hours so presenting symptoms might be reported over a longer period than in older patients. Common complaints from parents are generally non-specific and include increased fussiness, pallor, poor feeding, sleepiness, quick breathing, or increased spit ups/new vomiting. On exam, infants will be tachycardic with heart rates greater than 220. They may have signs of decreased peripheral perfusion such as delayed capillary refill. Signs of congestive heart failure will likely only be present if the episode has lasted more than 24 hours. An ECG is used to identify SVT. Most cases of SVT will present with a narrow QRS and absent or abnormal p-waves.

Differentiate compensated from decompensated shock in an infant (analysis)

Children tend to compensate well initially. In compensated shock, homeostatic mechanisms help maintain systolic blood pressure within the normal range for age. To compensate, the heart rate will increase and peripheral vasoconstriction occurs. Findings on exam may include delayed capillary refill, diminished pulses, and cool extremities. Once compensatory mechanisms have been exhausted, decompensated shock (now referred to as hypotensive shock in PALS) occurs. Systolic hypotension and altered mental status from brain hypoperfusion occur. Decreased respiratory drive can occur as cardiovascular collapse ensues.

Demonstrate physiologic (vagal), pharmacologic, and electrical cardioversion for SVT (application)

Vagal maneuvers can be attempted while other supplies and medications are gathered. The patient should be on a continuous ECG monitor while attempts to break SVT are made. Defibrillator pads should also be in place. In infants, a bag of ice and water may be placed over the face (without obstructing the nose and mouth) for 15-30 seconds in an attempt to elicit the “diving reflex.” Rectal stimulation via thermometer insertion is another method. Carotid massage should not be performed in infants. Orbital pressure should be avoided in all patients, as this may result in retinal injury.

If the rhythm is not rapidly converted by vagal maneuvers, pharmacologic management should be emergently instituted. For stable SVT, adenosine 0.1 mg/kg (max 6 mg) should be administered by rapid IV injection. If SVT continues, 0.2 mg/kg (max 12 mg) should be used for subsequent doses.

For refractory SVT in the setting of decompensated (hypotensive) shock, synchronized cardioversion at 0.5-1 J/kg should be performed. If not effective, increase to 2 J/kg. The patient may receive sedatives such as fentanyl, versed, ketamine, or etomidate before, but cardioversion should not be delayed if the patient is unstable.

If cardioversion attempts are not working, then the learners need to consider adding an antiarrhythmic medication (amiodarone 5 mg/kg or procainamide 15 mg/kg). In older children, verapamil 0.1-0.3 mg/kg may be considered for use in refractory SVT. However, it should not be used in infants as it may cause myocardial depression, hypotension, and cardiac arrest. Beta-blockers such as esmolol may be considered for refractory SVT that is well tolerated. If the patient is stable, a cardiology consultation is strongly recommended prior to giving antiarrhythmics other than adenosine.

Demonstrate BMV in an infant (application)

When? If the patient is not adequately ventilating on his/her own, it is very important for us to do this for him/her. The most common scenarios will be when the patient exhibits the follow conditions:

  • Inadequate respiratory effort
  • Hypoventilation
  • Apnea

These can all be caused by a variety of issues but it is imperative that the learners recognize this early and intervene given that respiratory arrest is the MOST common reason for an arrest in pediatrics.


  1. Positioning: Make sure that the patient is in the appropriate anatomical position and that the airway is patent. This can be hard in children under 4 years old, because their heads are large in proportion to their bodies and will cause them to flex and obstruct their airways. To make sure they are in a neutral position, slide a roll or towel under the shoulders. The goal is to elevate them by 2 inches.
  2. Tilt the head back and lift the chin: This will pull the tongue and airway up and forward to open the airway. It is very important
    to remember that the pediatric airway is much less developed and floppier, and thus can “fall back” and cause obstruction in patients. This maneuver is often enough but remember that oral airways and nasal trumpets can be used in some patients.
  3. Size matters: There are 3 different mask sizes and if your mask is too big or too small, you will not have a good seal. So if the mask doesn’t look correct, try another one. For self-inflating bags, there are multiple sizes as well. These are designed to limit total volumes based on patient size and thus, reduce associated barotrauma from BMV. The goal is for tidal volumes between 5-8 mL/kg.
  4. Seal is crucial: If you are short staffed, then one person can hold the mask in place and bag at the same time. This is done using the “EC” technique. With your left hand, hold the mask with your thumb and index finger creating a “C” to hold the mask to the face. Then position your 3rd, 4th and 5th digits along the jaw to make an “E” and lift the jaw up to the mask. “Push down” with the C part and “pull up” with the E part, making a tight seal between mask and face. Then bag with the R hand and keep the seal with the L hand. This can be difficult to do and will require practice to master this technique. Ideally, if you have adequate staffing, you should use a two-person technique. In this case, a second person holds the mask in place using “EC” technique on both sides of the mask. This allows one to maximize the seal between the mask and the face and allows optimal positioning of the airway to achieve adequate ventilation. The other person can then focus on bagging and observing the child’s chest for adequate chest rise.
  5. How fast? For pediatric patients, you should provide a breath about every 3-5 seconds or a rate of 12-20/minute (for neonates, the rate is one breath every 3 seconds or 40-60 breaths/min). Remember that you MUST let the patient exhale or they will not be adequately ventilating and they will build up CO2. If they are intubated, the rate is one breath every 6 seconds (10 breaths/min).
  6. Which bag? You can use either a self-inflating bag or an anesthesia bag, depending on availability or practice patterns at your institution. The self-inflating is technically easier because it does NOT require that you be connected to an oxygen source. Ideally, one should always be connected to oxygen and that way you can treat any hypoxia if present, but the anesthesia bag WILL NOT work without an active gas source to inflate it. Self-inflating bags also come with a pressure setting so that you can increase or decrease your maximum inspiratory pressure and thus, prevent barotrauma of the lungs. Note that self-inflating bags cannot be used to provide CPAP, while the anesthesia bags can do this.

Common pitfalls and debriefing points:

  • Was the patient in the appropriate position to maximize his/her airway? Most commonly, the learners will forget that a child’s head is larger than an adult’s and will not compensate for this.
  • Was the mask sized appropriately for the patient’s size/age? Again, this is a very common error and using the wrong size means poor seal and poor BMV technique.
  • Was the size of bag used appropriate for the patient?
  • Did they use single or two-person technique for BMV? If so, did the person holding the mask use the appropriate “EC” grip with good seal? Did they maximize the airway by use head-tilt and jaw-thrust appropriately?
  • Was the bag used connected to an oxygen source?
  • What rate did they use? Was it appropriate for the age of the patient?
  • Did they use the right pressure setting if they were using a self- inflating bag?


Demonstrate focused history taking from a caregiver (application)

  • Components of history taking: Past medical history, surgical history, family history, medications, allergies, social history, vaccination history
  • Specifically for patients presenting with a seizure, recent illnesses, fever, and prior seizure history are all very important questions.

Explain diagnosis and management to caregivers (synthesis)

If personnel are available, one member of the team may stay with the family to gather history and explain interventions. Information should be relayed to the family using layperson’s terms. The rationale for interventions such as ice to the face, IV placement, cardioversion, and BMV should be explained preceding or at the time of occurrence, when possible.

Demonstrate teamwork and closed loop communication (application)

Teams may use different frameworks to improve team dynamics and communication. Below are a few definitions that may be helpful to discuss, adapted from the AHRQ TeamSTEPPS Pocket Guide.

  • Brief: Short session prior to start of encounter to share the plan, discuss team formation, assign roles and responsibilities, establish expectations and climate, anticipate outcomes and likely contingencies
  • Huddle: Ad hoc team discussion to re-establish Situation Awareness; designed to reinforce plans already in place and assess the need to adjust the plan
  • Callout: A strategy used to communicate critical information during an emergent event. Helps the team prepare for vital next steps in patient care. (Example: Leader- “Airway status?”; Surveying provider- “Airway clear”; Leader- “Breath sounds?”; Surveying provider- “Breath sounds decreased on right”)
  • Check-back: A closed-loop communication strategy that requires a verification of information ensuring that information conveyed by the sender is understood by the receiver as intended. The sender initiates the message; the receiver accepts it and restates the message. In return, the sender verifies that the re-statement of the original message is correct or amends if not. (Example: Leader- “Give diphenhydramine 25 mg IV push”; Med Prep- “Diphenhydramine 25 mg IV push”; Leader- “That’s correct”)
  • SBAR: A framework for team members to structure information when communicating to one another.
    • S = Situation (What is going on with the patient?)
    • B = Background (What is the clinical background or context?)
    • A = Assessment (What do I think the problem is?)
    • R = Recommendation (What would I do to correct it?)
  • Situation monitoring: The process of continually scanning and assessing a situation to gain and maintain an understanding of what is going on around you.
  • Situation awareness: The state of “knowing what’s going on around you.”
  • Shared mental model: Result of each team member maintaining situation awareness and ensures that all team members are “on the same page.” An organizing knowledge structure of relevant facts and relationships about a task or situation that are commonly held by team members.
  • STEP: A tool for monitoring situations during complex situations. A systematic method to review Status of patient, Team members’ performance and status, Environment, and Progress towards goal.
  • Cross-monitoring: A harm error reduction strategy that involves 1. Monitoring actions of other team members 2. Providing a safety net within the team. 3. Ensuring that mistakes or oversights are caught quickly and easily. 4. “Watching each other’s back.”
  • CUS: Signal phrases that denote “I am Concerned,” “I am Uncomfortable,” and “This is a Safety Issue.” When spoken, all team members should understand clearly not only the issue but also the magnitude of the issue.
Go to Next Tab – Files

Initial ECG

Post-Cardioversion ECG

Chest X-ray

Post-Intubation Chest X-ray

Download Case 16 supporting files


  • ECG Interpretation: Supraventricular tachycardia. Image from Dr. Michael Nguyen.
  • Post-Cardioversion ECG Interpretation: Sinus tachycardia. Image from Dr. Michael Nguyen.
  • Chest X-Ray Interpretation: Normal. Image from Dr. Rebekah Burns.
  • Post-Intubation Chest X-ray Interpretation: Endotracheal tube in place. Image from Dr. Rebekah Burns.
Go to Next Tab – SP Script

For the embedded participant playing the patient’s parent

Case Background Information

Your daughter is having an episode of supraventricular tachycardia or SVT. This is when there is a very fast heartbeat coming from the top chambers of the heart. Babies may be fussy, pale or even become unresponsive and need medicine called adenosine to return the rhythm to a normal rhythm. If the medicine doesn’t work, the baby needs electricity from a defibrillator machine to fix the rhythm. You are bringing your daughter to the Emergency Department because she has been fussy and not wanting to eat for the past 8 hours. This is very unusual for her and has never happened before.

Who are the Learners?

Emergency medicine residents

This case is specifically aimed at interns who are in their first year of specialty training and may have experience in gathering information from patients and families, and standard medical treatments and procedures. They may be less familiar with escalating medical therapies when first measures are not successful.

Standardized Patient Information

You brought your daughter to the Emergency Department because she has refused to eat for much of the day and has been very fussy and pale. She was fine when she first woke up. This is very atypical for her. You are worried she is sick but do not know with what.

Your demeanor is concerned but relatively calm. You do not want to obstruct care but want to know what is happening. Do not interrupt them if they are thinking out loud or discussing care with one another but ask questions when possible if they don’t explain what they are doing.

Patient Information

(Please remember not to offer any of this information, but when asked please respond while remaining in character.)

  • CHIEF COMPLAINT (your response to open-ended questions such as “what’s going on?” or “what can we do for you? Or “what happened?”): “She hasn’t wanted to eat in the past 8 hours.”
  • AGE: 6 months old
  • ADDITIONAL HISTORY: You first noticed the fussiness around 7 AM this morning. She woke up at 6:30 AM normally had a good feed. At 7 AM, she became fussy. At first, you didn’t think much of it because she occasionally gets fussy. Normally this improves after a diaper change, playing a song on her music toy, or some cuddles and a pacifier. She had a wet diaper at that time which was normal. None of your usual calming methods worked. She went to sleep at 10:30 AM for her normal late morning nap but woke up after 30 minutes fussy again. You have also noticed that she looks more pale than normal (this you just noticed over the past 4 hours). She also seems a little sweaty now. She has not had fevers, cough, congestion, emesis, or diarrhea. She has not received any medications. There are no medications other than acetaminophen and ibuprofen at home. She has not had any falls or injuries at home.
  • PAST MEDICAL HISTORY: Born at 37-weeks’ gestation. Spent 3 days in the hospital. Received oxygen but was not intubated at that time.
  • SOCIAL HISTORY: Lives with both parents. No pets. No smoke exposure. Attends daycare 5 days a week since 4 months of age. No travel.
  • FAMILY HISTORY: Unremarkable
  • ALLERGIES: No known drug allergies.
  • IMMUNIZATIONS: Up-to-date through 6 months
  • FEEDINGS: Normally takes 8 ounces of formula every 4 hours. Started table food last month and has had mashed peas, sweet potatoes, and avocados without issues.
  • WET DIAPERS: Only one wet diaper in past 12 hours
  • BIRTH HISTORY: Born by spontaneous vaginal delivery at 37 weeks to a 32 yo G1P1 woman. Normal prenatal care, no complications during pregnancy or delivery. Discharged home from hospital on day 2 of life with mom. Prior history of admission for bronchiolitis at 2 months of age.

Potential Dialogue

IMPORTANT: Do not offer unsolicited information. Please allow the learners to ask questions. Do not offer information unless they ask you.

Things you could say without being asked:

  • “I have never seen her this fussy before. She won’t take a bottle. All the normal things I do to calm her down like rock her and give her a pacifier aren’t working.”
  • “She is normally such a good eater and a pretty mellow baby.”

Things you might say triggered by events in the scenario:

If they place a bag of ice on your child’s face or tip the baby upside down without explaining to you what they are doing“Why does this have to be done?”
After they give adenosine“Did that work?”
If they start using a bag mask to help your child breath without telling you what they are doing“Is she not breathing?”
If they start CPR“Is she going to die?!”
Go to Next Tab – Ideal
Learners enter the room to find that the infant is alert but crying and fussy. They immediately place the patient on bedside monitors and recognize that the patient has a narrow complex tachycardia with evidence of diminished distal perfusion. Stable SVT is identified. Supplemental oxygen is provided, and an IV is placed. Vagal maneuvers may be attempted while access is being obtained and adenosine is being prepared. The patient is rapidly given at least 2 doses of adenosine without resolution of the arrhythmia. The patient’s circulation, oxygenation, and ventilation then deteriorate as she develops unstable SVT. The patient requires BMV with good response to appropriate bagging. Synchronized cardioversion is then attempted with return of sinus rhythm after administration of at least 1J/kg. After cardioversion, the patient becomes responsive and no longer requires BMV.

Anticipated Management Mistakes

  1. Intubation of patient during decompensated SVT: We found that learners sometimes proceeded to intubate the patient rather than provide BMV while cardioverting the patient. In this scenario, this leads to PEA, requiring CPR and epinephrine. We found it helpful to discuss the risk/benefit of intubation when effective oxygenation and ventilation can be provided by BMV during an arrhythmic event. Facilitators may also point out signs of adequate bagging such as chest rise, equal breath sounds, and improvement in SpO2.
  2. Excessive fluid resuscitation: Some of our learners may provide aggressive fluid resuscitation in an attempt to normalize heart rate and blood pressure. Given the underlying cardiac dysfunction in the setting of SVT that has likely been present for several hours, this can lead to volume overload and signs of heart failure. Facilitators can point out decreasing SPO2 and worsening crackles and hepatomegaly to clue in learners.
  3. Delivery of unsynchronized shock: The patient does not ever lose a pulse in this scenario, and therefore should be managed using the PALS “pediatric tachycardia with a pulse and poor perfusion algorithm.” If an unsynchronized shock is delivered to the patient, she will develop ventricular fibrillation requiring CPR and defibrillation. The indications of synchronized cardioversion should then be reviewed during the debriefing. Alternatively, a facilitator can also reorient learners to the appropriate algorithm and provide real time guidance before an unsynchronized shock is delivered to the patient.


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Learner (scan or click on QR code)

Facilitator (click or scan QR code)