🏊 Chapter 117: Submersion Injury (Drowning)

Definitions · Pathophysiology (hypoxemia, surfactant loss, ARDS) · Rescue CPR (5 rescue breaths first) · Hypothermia protection · Prognosis (unwitnessed, prolonged submersion) · PICU lung & brain protection

🔍 Core Concepts: Submersion Injury

📌 Definitions (WHO 2002)
Drowning: respiratory impairment from submersion/immersion. Fatal vs non-fatal drowning. Avoid terms "near-drowning", "dry/wet".
🫁 Pathophysiology
Hypoxemia from aspiration (fresh/salt water similar) → surfactant loss, ARDS, V/Q mismatch. Neurologic injury from hypoxia, not electrolyte shifts.
🆘 Rescue & initial CPR
Rescuer safety first. Unresponsive: 5 rescue breaths before chest compressions (hypoxic arrest). C-spine immobilization only if diving/high suspicion.
❄️ Hypothermia & prognosis
"You are not dead until warm and dead." Continue resuscitation until rewarmed (core >32-34°C). Prolonged submersion >60 min, unwitnessed, asystole → poor prognosis.
🫀 PICU management
Lung protective ventilation (ARDSnet), treat myocardial dysfunction, mild therapeutic hypothermia (35-36°C) for cerebral protection, seizure control.
⚠️ Poor prognostic factors
Unwitnessed event, prolonged resuscitation, CPR at scene, fixed pupils in ED, coma >72h, elevated ICP signs.

🩺 Stepwise Management of Submersion Injury

1
Scene safety & rescue
Rescuer safety first. Remove from water with spinal precautions if diving or suspected head/neck injury.
2
Initial assessment & CPR
Unresponsive? Open airway, give 5 rescue breaths (hypoxic arrest), then 30:2 compressions:breaths. Do NOT attempt abdominal thrusts or drain water from lungs.
3
C-spine management
Immobilize only if high-risk mechanism (diving, water slide, signs of injury). Routine immobilization not indicated for all drowning.
4
Hypothermia protocol
Measure core temperature. Continue ALS until patient rewarmed to ≥32-34°C and still asystolic. Warm fluids, warm humidified oxygen, consider bypass if refractory.
5
ED & PICU management
Secure airway if GCS <8 or hypoventilation. Lung-protective ventilation (tidal volume 6 mL/kg, PEEP, permissive hypercapnia). Treat seizures, mild hypothermia (35-36°C) for 24-48h post-ROSC for neuroprotection.
6
Prognostication
Poor signs: unwitnessed, submersion >10-20 min, CPR >30 min, fixed pupils at presentation, coma >72h. MRI/EEG after 72h.