Skin hemodynamics during change from supine to lateral position

Area of Science:

• Physiology
• Neurology
• Biomedical Engineering

Background:

• Skin hemodynamics play a crucial role in thermoregulation and nutrient delivery.
• Autonomic nerve dysfunction is a common complication in various neurodegenerative diseases.
• Understanding skin blood volume changes during postural shifts is vital for assessing circulatory regulation.

Purpose of the Study:

• To investigate skin hemodynamics during supine to lateral position changes in patients with neurodegenerative diseases.
• To compare these hemodynamic responses with those of healthy volunteers.
• To identify the influence of autonomic nerve function on skin blood volume regulation during postural changes.

Main Methods:

• Utilized a portable, noninvasive near-infrared spectroscopy tissue oxygen monitor.
• Measured total hemoglobin concentration (indicating skin blood volume) in the left flank.
• Participants (19 neurodegenerative patients, 12 healthy controls) underwent sequential position changes: supine, left lateral, supine, right lateral, supine.

Main Results:

• Healthy volunteers exhibited predictable increases/decreases in skin blood volume upon changing from supine to lateral positions, with gradual recovery.
• Three patients with sporadic olivopontocerebellar atrophy (OPCA) and one Parkinsonian patient with severe orthostatic hypotension showed impaired recovery of skin blood volume.
• These findings suggest a link between autonomic dysfunction and altered skin hemodynamics during postural transitions.

Conclusions:

• Skin blood volume dynamically changes during supine to lateral position shifts.
• Autonomic nerve function is a key regulator of these intracutaneous blood volume changes.
• Impaired recovery of skin hemodynamics in certain neurodegenerative patients indicates compromised autonomic regulation.