ROLE OF PHYSICAL COUNTERMANEUVERS IN THE MANAGEMENT OF ORTHOSTATIC HYPOTENSION - EFFICACY AND BIOFEEDBACK AUGMENTATION

Objective: To evaluate the efficacy of various physical countermaneuve rs in reducing orthostatic hypotension and its associated symptoms and to assess the efficacy of biofeedback training in enhancing the effec tiveness of physical countermaneuvers. Material and Methods: In nine s tudy subjects with neurogenic orthostatic hypotension, four training s essions on physical countermaneuvers mere performed after tilt-up, thr ee with visual feedback on the effect of physical countermaneuvers on blood pressure and other cardiovascular variables. Blood pressure chan ge and orthostatic symptoms during tilt-up were determined, as were th e changes in total peripheral resistance, stroke index, and heart rate . Results: The five female and four male patients had a mean age of 53 years and a mean duration of symptoms of 4.2 years. On an orthostatic symptom scale of 0 to 10, these patients had a mean symptom score of 7.3. The increment in systolic blood pressure was better for some mane uvers (such as leg crossing and a combination) than others (such as ne ck flexion and abdominal contraction). Three patterns of responses to biofeedback were found. Simple maneuvers such as squatting did not imp rove with training; visual feedback was needed for maneuvers such as t high contraction, and performance declined without biofeedback; the th ird pattern, seen in maneuvers such as leg crossing, showed continued improvement with training, even without biofeedback. A survey at 3 to 4 months after training revealed continued use of physical maneuvers ( 3.8 +/- 3.1 per day), increased standing time with each episode of pre syncopal symptoms (8.3 +/- 5.8 minutes), and continued global symptoma tic improvement. Total peripheral resistance, but not heart rate or st roke index, showed significant regression with blood pressure improvem ent. Conclusion: Physical countermaneuvers are efficacious in reducing orthostatic hypotension, can be augmented by use of biofeedback, and may significantly improve the functional outcome. The major mechanism of improvement is an increase in total peripheral resistance, presumab ly by reducing the vascular capacitance.