11.2 Special Circumstances at Exam Level

Special Circumstances Still Use Core PALS

Special circumstances change emphasis and add cause-specific actions. They do not cancel high-quality CPR metrics, the shockable/nonshockable branch, weight-based epinephrine, or the evaluate–identify–intervene loop. On exam items, wrong answers often invent an entirely different algorithm; right answers apply PALS plus the circumstance-specific priority.

Drowning

Drowning produces hypoxic injury. Water aspiration, laryngospasm, and apnea drive hypoxemia that progresses to bradycardia and arrest. Rescue and bystander response that restore oxygenation early improve outcomes.

Priorities

1. Remove from the water safely; start resuscitation on a firm surface as soon as possible.
2. Open the airway and ventilate with oxygen—ventilation is a core priority because hypoxia is the driver.
3. If no pulse, start high-quality CPR with compressions and ventilations (pediatric conventional CPR, not hands-only as the preferred healthcare approach for children).
4. Attach AED/monitor; treat shockable rhythms if present (less common than hypoxic asystole/PEA but still possible).
5. Consider hypothermia after cold-water submersion: prevent further heat loss; rewarm per protocol; prolonged resuscitation may be appropriate while rewarming in selected severe hypothermia cases.
6. After ROSC, expect pulmonary injury, ARDS risk, and need for critical-care respiratory support—post-arrest care still applies (Chapter 12).

Exam traps

• Skipping ventilations because "compressions-only is always enough" in a drowning child
• Delaying CPR for prolonged attempts to "drain the lungs" with unproven maneuvers
• Declaring death immediately in a cold drowning victim without considering hypothermia physiology and rewarming

Anaphylaxis

Anaphylaxis is a distributive emergency that can obstruct the airway, cause bronchospasm, and produce shock or arrest.

Priority sequence

1. Remove ongoing allergen exposure when possible.
2. Give intramuscular epinephrine into the mid-anterolateral thigh immediately (autoinjector or weight-appropriate IM dose per protocol). IM epinephrine is first-line—not antihistamines, not steroids first.
3. Support airway early; edema can progress rapidly. Give oxygen; prepare for advanced airway if upper-airway obstruction or severe respiratory failure develops.
4. Place the child supine with legs elevated if shock is present and breathing allows; avoid sudden upright positioning that can worsen hypotension.
5. Establish IV/IO access; give isotonic fluid boluses for hypotension/shock with reassessment.
6. Adjuncts (antihistamines, corticosteroids, bronchodilators, epinephrine infusion for refractory anaphylaxis) follow after IM epinephrine.

If cardiac arrest occurs from anaphylaxis, run the standard pediatric arrest algorithm and treat the cause: IM or IV/IO epinephrine pathways per protocol, volume for distributive physiology, and aggressive airway management.

Pulmonary Hypertensive Crisis

A pulmonary hypertensive crisis is an acute, rapid rise in pulmonary artery pressure. Pulmonary blood flow falls, the left ventricle (or single ventricle) loses preload, and cardiac output collapses—producing systemic hypotension, myocardial ischemia, and arrest. Children at risk include those with idiopathic pulmonary arterial hypertension, congenital heart disease with pulmonary arterial hypertension, and the early postoperative cardiac surgical population.

Prevention: control the triggers

Hypoxemia and acidosis are both potent pulmonary vasoconstrictors, and pain or agitation raises pulmonary vascular resistance through sympathetic activity. The 2025 recommendations are therefore about physiology hygiene:

• Provide careful respiratory management and monitoring to avoid hypoxia and acidosis
• In mechanically ventilated at-risk children, provide adequate analgesia, sedation, and neuromuscular blockade
• Avoid dehydration, fluid overload, and anemia—hypovolemia drops preload, while volume overload congests a failing right ventricle, and anemia cuts oxygen-carrying capacity

Treatment of an active crisis

A final honest point for the exam: in a child with pulmonary hypertension who is already in cardiac arrest, it is unknown whether adding pulmonary hypertension–specific therapies improves CPR outcomes. Run standard high-quality CPR and the pediatric arrest algorithm; do not substitute a vasodilator for compressions.

Opioid Overdose: Pulse Present vs Cardiac Arrest

Opioids cause respiratory depression and apnea, leading to hypoxia and, if untreated, cardiac arrest. Public-access naloxone and healthcare naloxone use are emphasized in contemporary resuscitation systems of care.

Respiratory arrest or severe depression with a pulse

• Open airway; support ventilation with bag-mask and oxygen—do not wait for naloxone to start breathing for the child if ventilation is inadequate.
• Give naloxone per protocol (intranasal, IM, or IV/IO depending on setting and access).
• Reassess continuously; naloxone's duration may be shorter than some opioids—repeat doses or infusions may be needed.
• Monitor for withdrawal agitation after reversal, but treat life-threatening hypoventilation first.

Cardiac arrest (no pulse)

• Start standard high-quality pediatric CPR immediately.
• Use the full PALS arrest algorithm (rhythm checks, epinephrine 0.01 mg/kg IV/IO every 3–5 minutes, defibrillation if VF/pVT).
• Naloxone may be considered as an adjunct when opioid toxicity is suspected, but naloxone does not replace chest compressions, ventilation, or epinephrine.
• Exam trap: choosing "naloxone only, no CPR" for a pulseless child.

Trauma

Traumatic cardiac arrest and peri-arrest trauma care blend PALS with trauma priorities.

High-yield actions

1. Hemorrhage control: direct pressure, packing, tourniquet for life-threatening extremity bleeding; rapid movement toward definitive hemorrhage control for truncal bleeding.
2. Airway and ventilation with cervical spine motion restriction when mechanism suggests spinal injury—open the airway with jaw thrust when indicated; do not neglect oxygenation.
3. Bilateral breath sounds every assessment cycle: unequal sounds + shock → think tension pneumothorax → decompress.
4. Consider tamponade with penetrating chest trauma or suggestive physiology.
5. Volume resuscitation with blood products preferred for hemorrhagic shock/arrest per trauma systems; IO/IV access without delay.
6. Minimize scene time when definitive surgical care is required; high-quality CPR during transport when indicated by local protocol.

Trauma PEA is often hypovolemia, hypoxia, tension pneumothorax, or tamponade—run the T's aggressively rather than only giving epinephrine into an empty, obstructed, or exsanguinated circulation.

Congenital Single-Ventricle / Ductal-Dependent Reinforcement

Chapter 6 covers obstructive/ductal-dependent shock in depth. Exam-level reinforcement for arrest and peri-arrest:

• Neonates with ductal-dependent systemic blood flow (e.g., HLHS spectrum, critical coarctation, interrupted arch) can present in shock or arrest as the ductus closes.
• Prostaglandin E1 (PGE1) to reopen/maintain the ductus is a disease-specific bridge while arranging urgent pediatric cardiology/cardiac critical care.
• Avoid treating every gray neonate as pure hypovolemic gastroenteritis; differential pulses, lack of volume-loss history, and refractory shock push you toward congenital heart disease.
• Single-ventricle physiology after staged palliation is complex (shunt dependence, passive pulmonary blood flow in Fontan physiology)—exam items stay high-level: support ABCs, avoid harmful excessive ventilation or volume mistakes when taught, call specialty help early. Detailed surgical stage management is beyond typical provider PALS recall, but "this is not ordinary septic shock—get cardiology/PGE1 when ductal dependence is suspected" is fair game.

Family Presence During Resuscitation (2025 Concept)

Contemporary resuscitation guidance recognizes that family presence during CPR, when supported by institutional policy and a dedicated staff member, can reduce complicated grief and improve psychological outcomes for families. The 2025-era ethics and systems framing encourages organizations to:

• Develop policies defining when family presence is appropriate and when it may be precluded (safety, space, forensic constraints, or family preference to step out)
• Train teams to work with a family support person who explains events, answers questions, and escorts family if they need to leave
• Keep the clinical team focused on high-quality resuscitation—family presence is an adjunct to good care, not a replacement for closed-loop communication and role clarity

Exam-level takeaway: offering or allowing family presence when the system can support it safely is consistent with modern PALS/systems-of-care teaching; forcibly excluding all families without reason is outdated. Conversely, if presence would endanger the team or destroy resuscitation quality, the patient’s care remains the priority.

Clinical scenarios (synthesis)

Drowning: A school-age child pulled from a pool is unresponsive and apneic with no pulse. Start CPR with ventilations and compressions, oxygenate aggressively, apply AED/monitor. Do not choose hands-only-only care as ideal for this hypoxic arrest.

Anaphylaxis: A child with peanut exposure has stridor, wheeze, and hypotension. Give IM epinephrine in the thigh first; then oxygen, fluids, and airway readiness. Antihistamine-only first answers are wrong.

Opioid: An adolescent is apneic with pinpoint pupils and a strong pulse. Ventilate and give naloxone. If the same patient has no pulse, start CPR and run the arrest algorithm; naloxone is not a substitute for compressions.

Trauma: A restrained child in a high-speed crash loses pulses. CPR, hemorrhage control, C-spine precautions, check both lung fields, prepare for tension decompression, rapid transport/trauma activation.

Bottom line for 11.2: Special circumstances add priorities—ventilate drowning victims, IM epi for anaphylaxis, naloxone when pulse present with opioid respiratory failure, standard CPR in opioid cardiac arrest, hemorrhage/C-spine/breath sounds in trauma, PGE1/specialty path for ductal-dependent neonates, and support family presence when systems allow—without abandoning core PALS.