Drowning and hypothermia
Management
Remove wet clothing and cover.
ABC.
Warming – core and peripheral techniques.
Prevent secondary brain injury (neuroprotective measures).
Supportive treatment.
Warm water drowning (water >20) has a worse prognosis than cold.
Rewarming
Passive (prevention of heat loss)
Remove wet clothes
Blankets
Temp ↑ 0.5/h
Active
Peripheral
FAW
Hot water bottles
Note peripheral vasodilatation can lead to further heat loss and CVS collapse
Central
Warm IV fluids (max 40)
Warmed inspired gases (max 45)
Warm irrigation (max 40) - NG, bladder, pleural cavity
Intravascular warming catheter (warms blood as it goes past)
Haemofiltration (2h to get from 28-34)
Cardiopulmonary bypass (by far the most effective – 15mins)
Effects
CNS
Irreversible neuronal cell death begins within 5 min of inadequate cerebral oxygen delivery.
Significant primary brain injury promotes cerebral oedema, peaking in severity at 24–72 hours after the initial event
RS
Laryngospasm
Bronchospasm
VQ mismatch
Pulmonary oedema
Pneumonitis if chlorine or vomit
Up to 70% get ALI/ARDS due to surfactant loss
Remember if PO2 measured at 37 then it will be lower in the patient due to ↑ solubility at low temp
CVS (hypothermic effects)
Bradycardia progressing to complete heart block
J-wave (+ve deflection after QRS)
Refractory VF <28
Hypovolaemic shock
Extravasation
Cold diuresis (inability of kidneys to conserve water)
SIRS post resuscitation
Infection
If stagnant water
Better prognosis
Short immersion time
Cold water
No arrest
Conscious
Bystander CPR
Poor prognosis
>5mins submersed
Warm water
Arrest
No bystander CPR
Asystole
Fixed dilated pupils