Premium
Effects of increased systemic blood pressure on the tissue fluid pressure threshold of peripheral nerve
Author(s) -
Szabo Robert M.,
Gelberman Richard H.,
Williamson Richard V.,
Hargens Alan R.
Publication year - 1983
Publication title -
journal of orthopaedic research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.041
H-Index - 155
eISSN - 1554-527X
pISSN - 0736-0266
DOI - 10.1002/jor.1100010208
Subject(s) - blood pressure , wrist , medicine , median nerve , compression (physics) , anesthesia , peripheral , carpal tunnel syndrome , carpal tunnel , cardiology , anatomy , surgery , materials science , composite material
This study was designed to evaluate the functional response of the median nerve at the wrist to various degrees of acute, local compression in hypertensive patients. After measuring resting tissue fluid pressure in the carpal tunnel of the nondominant hand of nine subjects (diastolic pressures of 90 mm Hg or greater), localized pressures of 50, 60, or 70 mm Hg were applied to the palmar aspect of the wrist. Motor and sensory latencies and amplitudes of the median nerve were evaluated before compression, during 30–240 min of compression, and during the postcompression recovery phase. Sensory responses were completely blocked at a threshold tissue fluid pressure of 60–70 mm Hg, measured by the wick catheter technique. This pressure threshold was greater than the 40–50 mm Hg previously found in normotensive subjects. The tissue pressure threshold of normotensive and hypertensive subjects was consistently 30 mm Hg below diastolic blood pressure (approximately 45 mm Hg below mean arterial blood pressure). These results support the concept that ischemia is the prime mechanism of conduction block in low pressure, nerve‐compression syndromes.