Cold pressor test using strain-gauge plethysmography.

Area of Science:

• Physiology
• Cardiovascular Regulation
• Biomedical Engineering

Background:

• Peripheral blood flow regulation is crucial for thermal homeostasis.
• The cold pressor test (CPT) is a standard method to induce sympathetic nervous system activation and study vasoconstriction.
• Understanding the relationship between blood pressure, heart rate, and vascular resistance during CPT is essential for diagnosing cardiovascular conditions.

Purpose of the Study:

• To teach students how to measure forearm muscle blood flow (FBF) and analyze peripheral blood flow regulation.
• To investigate the physiological mechanisms of thermal regulation in healthy subjects using the CPT.
• To differentiate healthy and pathological responses to sympathetic stimulation by quantifying peripheral vascular resistance.

Main Methods:

• Utilizing strain-gauge plethysmography for noninvasive monitoring of forearm blood flow.
• Implementing the cold pressor test (CPT) to induce controlled arterial vasoconstriction.
• Calculating peripheral vascular resistance as the ratio of forearm muscle blood flow to mean arterial pressure.

Main Results:

• Demonstrated the ability to measure FBF and physiological parameters (BP, HR) during CPT.
• Quantified peripheral vascular resistance to elucidate its role in BP and HR changes during cold exposure.
• Provided a method to distinguish healthy vascular responses from those potentially indicative of hypertension or other conditions.

Conclusions:

• The laboratory activity effectively teaches methods for assessing peripheral vascular function.
• Quantifying peripheral vascular resistance during CPT provides critical insights into sympathetic nervous system influence on blood flow.
• This approach enhances understanding of cardiovascular biomechanics and thermal regulation in both healthy and diseased states.