Serum enzyme levels during experimental hypothermia in man

Area of Science:

• Physiology
• Biochemistry

Background:

• Hypothermia, both surgical and accidental, is associated with elevated serum enzyme levels, potentially due to cellular damage.
• The precise mechanisms and influencing factors in clinical settings remain unclear.
• Previous research indicates a link between hypothermia and enzyme level changes.

Purpose of the Study:

• To investigate the relationship between controlled hypothermia and serum enzyme levels in a laboratory setting.
• To monitor physiological parameters during induced hypothermia.
• To determine if mild hypothermia in healthy volunteers affects serum enzyme concentrations.

Main Methods:

• Four subjects were subjected to controlled hypothermia four times in a laboratory setting.
• Auditory canal temperature was reduced to a mean of 35.0°C.
• Serum enzyme levels and other physiological parameters were monitored throughout the cooling process.

Main Results:

• Mild hypovolemia and acidosis were observed in the subjects.
• No significant changes in serum enzyme levels were detected during the experiment.
• The controlled hypothermia protocol did not induce the expected enzyme elevations.

Conclusions:

• Elevations in serum enzyme levels due to hypothermia cannot be reliably studied in healthy volunteers cooled to 35°C in a laboratory.
• The mild hypothermia achieved in this study was insufficient to cause significant ultrastructural cell damage leading to enzyme release.
• Further research may require different models or more severe hypothermia to study this phenomenon.