Skin blood flow and temperature oscillations during cold pressor test

Area of Science:

• Physiology
• Biomedical Engineering
• Thermoregulation

Background:

• The cold pressor test (CPT) is a standard method to assess autonomic nervous system function and vascular reactivity.
• Understanding the interplay between skin blood flow and temperature regulation is crucial for diagnosing circulatory disorders.

Purpose of the Study:

• To investigate the relationship between skin blood flow and skin temperature variations during a cold pressor test.
• To analyze the dynamic changes in vascular tone and thermoregulation in response to cold stimuli.

Main Methods:

• Simultaneous measurements of laser Doppler flowmetry (LDF) for skin blood perfusion and skin temperature (ST) were performed.
• Data were collected from the fingers of 8 healthy subjects during a contralateral CPT.
• Power spectral density analysis was used to assess variations in LDF and ST signals.

Main Results:

• Skin blood perfusion decreased stepwise during CPT in all subjects.
• Mean finger pad temperature dropped by approximately 1°C.
• LDF and ST pulsations showed distinct responses, with changes in amplitude being strongly anticorrelated across subjects.
• Two distinct patterns of myogenic mechanism response (0.1 Hz pulsations) were observed.

Conclusions:

• CPT significantly alters skin blood flow and temperature, demonstrating complex vascular responses.
• The anticorrelation between perfusion and temperature pulsations suggests intricate regulatory mechanisms.
• Further research into these vascular reactions can elucidate physiological responses to cold exposure.