Clinical Physiology Laboratory
In the Department of Orthopaedic Surgery
Visit UC San Diego Department of Orthopaedic Surgery
Explore other UCSD Health Sciences Sites
UC San Diego Clinical Physiology Laboratory • 9452 Medical Center Drive • La Jolla, CA 92037-0863 • 858-534-4655
About the Lab | Research | People | Publications | Contact
Official Web Site of the University of California, San Diego. Copyright ©2018 Regents of the University of California. All rights reserved.
Legal | Policy Notices | Site Feedback
Home / Research / Microvascular Flow
Microvascular Flow Research Projects
Increasing Microvascular Flow with External Compression to Improve Foot Sensation
Purpose: Therapies utilizing external compression of the leg are employed to prevent deep venous thrombosis, decrease
lower extremity edema, manage chronic venous insufficiency, and increase healing in the treatment of venous stasis ulcers.
Moreover, patients with diabetes or other peripheral vascular diseases have decreased capillary density, reduced arterial
inflow, and poor microvascular blood flow limiting wound healing and tissue viability. Alterations in the microcirculation involve
degeneration of the small arteries, arterioles, capillaries, and post-capillary venules. This leaves patients with a higher risk of
non-traumatic foot injuries and toe amputations. The goal of this experiment is to measure microvascular blood flow and foot
sensation by applying continuous and cyclic mild external compression on the subject’s calf in order to determine how blood
flow changes in the lower extremities with mild compression and the resultant change in foot sensation.
Hypothesis: Intermittent pneumatic compression will increase microcirculatory blood flow in both healthy and diabetic
Technologies used: Single leg chamber, PPG, NIRS, and sensory monofilaments.
Hand and Leg Volume Changes with Water Immesion Related to Cardiovascular Health
Purpose: Wrinkling of the fingers is commonly seen when hands are immersed in
water. However, if there is excess wrinkling, it can be indicative of a disease condition
such as cystic fibrosis. Or if there is less to no wrinkling, it might reflect a sympathetic
nervous dysfunction or a vascular disease. We aim to establish a link between the
wrinkles on the hand and changes in hand volume and age related changes. This
study may be used as a simple and non-invasive test to estimate age related tissue
health, autonomic dysfunction and as a diagnostic marker of cystic fibrosis, cardiac
deconditioning and vascular disease.
Hypothesis: The wrinkling of skin, and associated limb volume changes, are age dependent and can bring to light age related
Technologies used: Limb volume water displacement, CCFP, IOP, LBNP
Noninvasive Measurement of Microvascular Flow in Skin and Muscle
Purpose: During microgravity conditions a cephalad fluid shift occurs causing the mean arterial pressure at the feet reduces
from 200 mmHg to about 100 mmHg and also causing mean arterial pressure at the head to increase from 70mmHg to
100mmHg. This redistribution of pressures and fluid in microgravity leads to decreased bone mass density as well as muscle
deconditioning during long duration space flight. This increases the risk of osteoporosis and fracture upon return to Earth for
astronauts. The use of lower body negative pressure is a known countermeasure used to help combat the severity of the
cephalad fluid shift that occurs during spaceflight. We aim to better understand how varying external pressure exposure will
affect circulation to the lower extremities. We will be investigating how mild variations in positive and negative pressure
exposures to different regions of the lower body will affect tibialis anterior muscle and overlying skin microvascular blood flows
as well as leg circumference.
Hypothesis: There will be an overall increase in microvascular muscle blood flow during intermittent compression.
Technologies used: Lower body pressure chambers, PPG and strain gauge.