A STUDY OF POST-ISCHAeMIC PARAeSTHESIAe

Abstract

Post-ischemic paresthesiae consist of 4 sensory components: thermal, buzzing or tingling, pricking, and pseudo-cramp. A 12-cm. cuff above the elbow, inflated to 200 mm. Hg, produces no changes for 2 min. Ischemic paresthesia, a soft tingling sensation, rises to a peak by 3 min., subsides and disappears by 5 min. Paralysis and anesthesia occur at 15 min. Release of cuff at 30 min. produces a thermal paresthesia during the first 30 sec. At 1 min. 10 sec. after release both anesthesia and paralysis disappear. At 50 sec. tingling begins and is gone at 10 min. Pseudo-cramp develops at 50 sec. and subsides to disappearance at 3-4 min. Pricking begins at 70 sec. and is gone at 12-15 min. The sensations are severe and complex 2 min. after release. Less than 5 min. ischemia produces no post-ischemic symptoms, but pricking and tingling increase with longer ischemic periods. Pseudo-cramp appears only after 20-25 min. ischemia. Individuals vary as to onset, duration and relative intensity. Sensory end organs and peripheral nerves need not be intact. Post-ischemic paresthesiae are due to recovery of nerves beneath and peripheral to the point of occlusion, and increase with the peripheral lengths of the nerves. Conduction is by nerves normally mediating touch, pressure, movement and position, the sympathetic nerves and those mediating pain and temp. not being involved.