An objective assessment of the sudomotor response after thoracoscopic sympathectomy

Thoracoscopic sympathectomy has become an accepted therapeutic option for palmar hyperhidrosis. Objective assessment of sweat output after sympathectomy, however, has not been reported to date. We report for the first time sweat output measurements after sympathectomy during a 3-year postoperative period.

Thoracoscopic sympathectomy was performed by division of T2 and T3 sympathetic ganglia in 17 healthy adult patients with no comorbidities. Preoperative and postoperative sweat measurements were done at 29 degrees C (below sweat threshold, at baseline, after conversation, and after a mental arithmetic challenge) and at 40 degrees C (baseline and after exercise) with the ventilated capsule technique in left palm, sole, and chest wall. Serial postoperative measurements were conducted at 1 and 6 months and 1, 2, and 3 years.

Sweat output fell significantly after sympathectomy relative to preoperative levels under all experimental conditions (P < .001, analysis of variance) in the left palm. Differences in sweat outputs in the left palm were statistically significant between groups at baseline and postoperatively after mental arithmetic challenge and exercise at 40 degrees C (P < .05, analysis of variance). Compensatory increases in the sweat outputs from the left sole and chest were observed after sympathectomy. No patients had recurrence of preoperative sweat output values at follow-up.

According to objective sweat output measurements, thoracoscopic sympathectomy results in long-term control of palmar hyperhidrosis. This evaluation method is valuable in investigating recurrence of symptoms or compensatory hyperhidrosis after sympathectomy, providing a robust and objective criterion for planning intervention.