Submersion injury

Background

• Defined as respiratory impairment from submersion in liquid (regardless of pt outcome)
• No significant clinical differences between fresh-water and salt-water injuries
• No significant clinical differences between dry and wet drowning
• Epidemiology
  • Common in children <5yr, teenagers, and elderly
• Pathophysiology
  • Submersion>panic>voluntary breath holding>laryngospasm>reflex inspiration>aspiration

Diagnosis

• History
  • Important to get witness and EMS accounts
  • Ask about trauma, ETOH, temperature of water, submersion time, PMH
  • Important to assess for trauma and causes of syncope resulting in drowning
  • Always consider non-accidental trauma
• Primary Survey
  • A-Intubate if not breathing or unable to protect the airway
  • B-If pt is severly hypothermic, ventilate at half the normal rate
  • C-Watch for "afterdrop" with rewarming when hypothermic
    • Peripheral vasodilation -> cool blood returning to the heart
  • D-Baseline neurological exam is crucial
  • E-Remove all wet clothing, observe for signs of trauma

Work-Up

1. CXR (pulm edema)
2. Labs
   1. CBC, Chemistry, troponin, coags, UA, total CK
3. CT head/C-spine (if history of trauma)
4. ECG
   1. Dysrhythmias are common in hypothermia

Treatment

1. Neurologic
   1. Assume C-spine injury if unclear mechanism
   2. Intubate to protect airway if indicated
   3. Control seizures if they occur, consider sub-clinical status epilepticus
2. Pulmonary
   1. O2 to keep SaO2 >95%
   2. Significant injury often requires intubation and mechanical ventilation (high PEEP)
   3. If severly hypothermic, ventilate at half the normal rate
3. Cardiovascular
   1. IV fluid for volume depletion (common secondary to cold diuresis)
   2. Arrhythmias
      1. Defibrillate with normal Joules
      2. If initial defib attempt unsuccessful and temp <32, rewarm to 32 deg and reattempt
         1. Rewarm with passive versus active depending on degree of hypothermia
4. ID
   1. Abx
      1. Controversial
      2. Consider if concerned for pulmonary aspiration (must cover pseudomonas)
5. Resuscitation
   1. Length
      1. Controversial
         1. Must weigh against devastating neuro injury with ROSC after prolonged resuscitation
      2. Recommend at least 30 min in warm water drowning, 60 min in cold water
      3. Longest submersion time with full recovery is 66 min, occurred in cold water
   2. Potassium
      1. Value >10 mmol/dL not compatible with resuscitation in pts with hypothermia

Disposition

• GCS >13, O2 sat >95%, normal pulm exam
  • Consider discharge after 4-6hr of obs
• GCS <13, supp O2 required, or abnormal pulm exam
  • Admit

Prognosis

• Poor prognosis associated with:
  • Prolonged submersion and resuscitation, low GCS, warm water, asystolic rhythm, male
  • Hypothermia is actually a POOR prognisticator as it indicates prolonged submersion

Source

• Tintinalli's
• Pediatric EM Practice