Drowning

Some facts

Drowning is important: 1,000 people drown every day, 2 every 3 minutes, 41 per hour. It is the world’s 3rd leading cause of accidental death: 3.6 million people over 10 years.

Disease of youth

• 64% < 30 years old
• 43% < 15 years old
• 25% < 5 years old

Male: female ratio 2:1

In 40%, alcohol is on board

4 stages of Immersion associated with particular risk in drowning

Initial Responses/Sudden Death (first 3-5 min)

• Skin cooling

Short-Term Responses (5-30 min)

• Superficial Nerve and Muscle Cooling

Long-Term Responses (30 min +)

• Cooling of deep tissues

Post-immersion (during rescue)

• Collapse of arterial pressure
• Continued cooling

Fresh versus salt water drowning

Lethal aspiration of salt water 22ml/kg (approx 1.5 litre), fresh water 44ml/kg

Be aware that drowning can take up to 4 hours – observe and watch for 6!

Prognostication

Better outcomes:

• Rescued and BLS commenced < 5-10 min
• Children
• Those who have not aspirated
• Water temperature < 10 ^oC, core body temperature 33-35 ^oC
• Neurologically intact on arrival at hospital
• Minimum blood pH > 7.1, blood glucose < 11.2mmol/L
• ROSC on scene
• Spontaneous ventilation in ED

Worse prognosis

• Risk of death or severe neurological impairment after hospital discharge is reported to be nearly 100% when the duration of submersion exceeds 25 min
• Following 30 mins resuscitation, if no signs of life, resuscitation is futile -> stop

It is important to remember that casualties who have entered water sometimes have access to a “bubble” of air – particularly if they had entered the water following a boating incident or were in a car at the point they entered the water. In these circumstances it is impossible to judge the point at which submersion has occurred. 

What about cold water???

This is a regular point of discussion and concern. Water temperature is a key determinant: icy versus not. In the UK sea water is very unlikely to be icy or cold enough – however, small areas of water may well be, particularly in the winter months. 

References

• Szpilman D, Bierens JJ, Handley AJ, Orlowski JP (2012) Drowning. New Engl J Med. 366: 2102–10. 
• Tipton & Golden (2011). Decision making guide for immersion incidents involving total (head under) submersion. Resuscitation. 82: 819-824.
• Golden & Hervey, 1981 
• Oakley & Pethybridge, 1997
• Tipton 2016
• Bierens 2014. Handbook of Drowning.