Experimental hypothermia by cold air: a randomized, double-blind, placebo-controlled crossover trial

Area of Science:

• Medical Research
• Clinical Trials
• Hypothermia Studies

Background:

• Accidental hypothermia presents significant morbidity and mortality risks.
• Research challenges include low incidence and patient heterogeneity.
• A new method for experimental hypothermia trials is needed for active rewarming studies.

Purpose of the Study:

• To develop and validate a novel protocol for inducing mild hypothermia.
• To assess the efficacy of cold ambient air as a cooling method.
• To determine if drug-induced suppression of thermoregulation is necessary.

Main Methods:

• Randomized, double-blind, crossover trial with 15 healthy volunteers.
• Exposure to 5°C windy climate chamber with wet clothing.
• Comparison of active drugs (meperidine, buspirone) versus placebo.

Main Results:

• A mean core temperature difference of 1.7°C was observed between drug and placebo groups.
• Shivering was reduced but not fully inhibited by the drug regimen.
• Core temperature decreased at an average rate of -0.82°C per hour.

Conclusions:

• The developed protocol using cold air and drug intervention is effective for inducing mild hypothermia.
• This method facilitates future research into accidental hypothermia and active rewarming.
• Minor protocol adjustments are suggested for optimization.