Background
• AHA guidelines suggest a broad definition of drowning to include death from drowning, near drowning, wet drowning, etc.
• Traditional definitions still used:
• Drowning = death from asphyxiation from fluid aspiration after submersion in liquid
• Dry drowning = asphyxia from severe laryngospasm, no significant fluid aspiration
• >4000 drowning deaths annually in US, toddlers & teenage boys at greatest risk
• Freshwater vs. saltwater vs. chlorinated pool water: No difference, theoretical diff only
• Primary insult to lung; water moves across alveolar-capillary membrane, destroys (freshwater) or washes out (salt water) surfactant → hypoxia
• Diving reflex = immersion of face in water <68°F, blood shunts from periphery → brain & heart → apnea, bradycardia, hypothermia → ↓metabolic demand prevents/delays severe cerebral hypoxia
Approach
• Careful hx: Possible diving (cervical spine or head) injury vs. primary drowning, intoxicants, comorbidity, submersion time, water temp, initial rescuer response (ACLS)
• Extricate pt, remove wet clothing, ABCs, ACLS, intubation as appropriate
• Bedside glucose or D50 if AMS
• Cervical spine immobilization if suspicion for head or neck injury (diving, pool accident)
History
• Submersion event
Findings
• Variable presentation (awake, coma, cardiac arrest)
• Wheezes/rales/rhonchi, ecchymosis/crepitus/other signs of trauma on exam
Evaluation
• CBC, Chem 7, LFTs, tox, CXR may show pulmonary edema or aspiration 2–6 h after event, CT head & c-spine if concern for trauma, AMS
Treatment
• ABCs, intubation or supplemental O2, CPR, ACLS, Foley placement
• Measure core temp, treat for hypothermia if indicated to temp 30°C/86°F
• Ventilator PEEP 5–10 mm H2O to ↓ intrapulmonary shunting
Disposition
• Admission for continued tx, watch for signs of ARDS/VALI
• May develop pulm Δ even after mild submersion, observe asx pts for at least 8 h
Pearls
• Prophylactic abx & steroids not indicated
• Artificially induced hypothermia does not improve outcome