ing thermogenesis and the pediatric patient cannot compensate for
hypothermia by shivering until they are several years old. The rapid
movement seen with shivering consists of asynchronous muscular
activity that suggests there is no central modulator to this activity.
There is, however, a slower synchronous pattern of activity that is
superimposed on the fast muscular contraction. This is presumed to
be centrally mediated.
7. Adverse consequences of even mild hypothermia include __________ .
a. hypercoagulability
b. decreased drug metabolism
c. hypoventilation
d. hypoglycemia
b. Coagulation is impaired by even mild hypothermia leading to poten-
tially increased blood loss. A cold-induced defect in platelet function
is the primary problem, although hypothermia directly impairs the
enzymes of the coagulation cascade as well. Initial respiratory
response to mild hypothermia is a centrally mediated hyperventilation
often producing an initial respiratory alkalosis. Hypoventilation and
abnormal breathing patterns are seen with more severe drops in body
temperature and/or residual effects of anesthetics. Humeral stress
responses to the development of mild hypothermia lead to increases
in plasma glucose and drops in plasma insulin levels. The resultant
hyperglycemia further increases the risk of surgical site infection,
which is directly increased by the effects of hypothermia on immune
cell function. Drug metabolism is markedly decreased by periopera-
tive hypothermia. Prolonged duration of action of neuromuscular par-
alytics, IV sedatives and inhalational agents are all observed in
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