Submersion injury

Background

• Definition: "The process of experiencing respiratory impairment from submersion/immersion in liquid"
  • Term "near-drowning" no longer used
• Three possible outcomes = death, survival with morbidity, survival without morbidity
• Consider secondary causes such as intoxication, syncope, cardiac arrhythmia, ACS, non-accidental trauma, etc.

Pathophysiology

• Submersion → voluntary breath holding → aspiration → coughing/laryngospasm → aspiration continues → hypoxia → death
• Aspiration destroys surfactant which → alveolar collapse, atelectasis, non-cardiogenic pulmonary edema, and V-Q mismatch.

Differential Diagnosis

Water-related injuries

• Hypothermia
• Immersion pulmonary edema
• Marine toxins, envenomations, and bites
• Scuba diving emergencies
• Submersion injury (drowning and near-drowning)

Evaluation

• CXR
• ABG

• Other work-up generally not needed unless specifically indicated by history or exam, but may consider:
  • Labs, EKG
  • CT head/C-spine (if history of trauma) - C-spine injury extremely unlikely without evidence or history of trauma (<0.5% in large cohort study)

Management

Neurologic

• Assume C-spine injury if unclear mechanism
• Intubate to protect airway if indicated
• Control seizures if they occur, consider subclinical status epilepticus

Pulmonary

• O2 to keep SaO2 >95%
• Significant injury often requires intubation and mechanical ventilation (high PEEP)
  • Strong considerations for intubation: if on high flow oxygen with: O2 saturations <90%, or PaO2 <60 (adults) <80 (peds), or PaCO2> 50
• If severely hypothermic, ventilate at half the normal rate

Cardiovascular

• IV fluid for volume depletion (common secondary to cold diuresis)
• Arrhythmias
  • Defibrillate with normal Joules
  • If initial defib attempt unsuccessful and temperature <32, rewarm to 32 deg and reattempt

Hypothermia

• Rewarm with passive versus active depending on degree of hypothermia
• Occurs more quickly in pediatric population secondary to lower body mass:surface area

ID

• Empiric Antibiotics
• Consider if immersion with grossly dirty water (sewage, glades...)
• Consider if concerned for pulmonary aspiration (must cover pseudomonas)

Resuscitation

• The length of resuscitation to achieve ROSC must weigh against devastating neuro injury with ROSC after prolonged resuscitation
• Recommend at least 30 min in warm water drowning, 60 min in cold water
• Longest submersion time with full recovery is 66 min, occurred in cold water with ECMO rewarming

Potassium

• Value >10 mmol/dL not compatible with resuscitation in patients with hypothermia

Disposition

• Discharge after 4-6 hours of observation if:
  • Normal mental status, SpO2 >95% on room air, normal respiratory exam
• Admit all others

Prognosis

• Poor prognosis associated with:
  • Prolonged submersion time (11-25 mins associated with 88% mortality rate)
  • Time until BLS >10 mins
  • Resuscitation >30mins
  • Initial GCS<5
  • Age<3
  • Core temperature <33C (Hypothermia is actually a POOR prognostic factor - indicates prolonged submersion)

See Also

• Water-related injuries
• Immersion pulmonary edema

Video

{{#widget:YouTube|id=FznXbFcHLdM}}