If cardiopulmonary resuscitation (CPR) is required,
the risk of neurologic damage is similar to
that in other instances of cardiac arrest. However,
hypothermia associated with drowning can provide
a protective mechanism that allows persons
to survive prolonged submersion episodes. Hypothermia
can reduce the consumption of oxygen
in the brain, delaying cellular anoxia and ATP depletion.
Hypothermia reduces the electrical and
metabolic activity of the brain in a temperaturedependent
fashion. The rate of cerebral oxygen
consumption is reduced by approximately 5% for
each reduction of 1°C in temperature within the
range of 37°C to 20°C.22