INCIDENCE AND MANAGEMENT OF AUTONOMIC DYSREFLEXIA AND OTHER INTRAOPERATIVE PROBLEMS ENCOUNTERED IN SPINAL-CORD INJURY PATIENTS UNDERGOING EXTRACORPOREAL SHOCK-WAVE LITHOTRIPSY WITHOUT ANESTHESIA ON A 2ND-GENERATION LITHOTRIPTOR

Spinal cord injury patients are at increased risk for urolithiasis and many will require treatment, most commonly with extracorporeal shock wave lithotripsy. New, second generation lithotripsy devices allow tre atment without tub immersion, and without general or regional anesthes ia for most patients' Spinal cord injury patients, with loss of sensat ion below the level of injury, would seem to be ideal candidates for s uch treatment. We present our experience with 20 consecutive spinal co rd injury patients treated without anesthesia on the Medstone STS seco nd generation lithotriptor. All patients were awake and experienced no direct sensation from the shock waves. All but 1 patient (T12 level), however, experienced autonomic dysreflexia, with significant elevatio ns in systolic blood pressure (mean increase 44 mm. Hg, maximum 74) an d diastolic blood pressure (mean increase 24 mm. Hg, maximum 61), with reflex bradycardia (mean decrease -22 beats per minute). Autonomic dy sreflexia was successfully treated in this setting with short-acting s ublingual nifedipine. Associated bradycardia was treated with atropine in 6 patients. Preoperative bowel preparation proved to be useful in spinal cord injury patients to maximize stone imaging and may decrease autonomic dysreflexia if this is caused by shock waves impacting on t he distended bowel. Other problems included uncontrolled skeletal musc le spasms elicited by shock waves, which proved to be troublesome in m aintaining patient position and stone localization. Muscle spasms were decreased with benzodiazepines. Care was also observed in spinal cord injury patients to pad all pressure points on the hard, dry treatment surfaces associated with second generation lithotriptors and, thus, p revent skin breakdown.