Cold water survival
Cold shock (zero to 2 minutes): gasp reflex, uncontrolled breathing, hyperventilation, rapid heart rate.
Functional disability (2 to 15 minutes): difficulty swimming, loss of functional ability, loss of manual dexterity, muscle cramping, swimming speeds onset of hypothermia.
Onset of hypothermia (after 30 minutes): cooling to unconsciousness; if head keeps going under, drowning within 30 to 120 minutes; if head remains above water, cooling to cardiac arrest in 90 to 180 minutes or more, depending on water temperature, body size, clothes and other factors.
See related article:
April 2013 issue