The body mass index and level of resection: predictive factors for compensatory sweating after sympathectomy

Compensatory sweating (CS) is the most common adverse event and the main cause of dissatisfaction among patients undergoing a VATS sympathectomy for the treatment of primary hyperhidrosis. It has been described that obese individuals experience more sweating than thinner ones. The aim of this study is to identify the Body Mass Index (BMI) and the level of resection as predictive factors for CS and its relation to levels of patient satisfaction following the procedure.

From October 1998 to June 2003, 102 patients undergoing VATS sympathectomies (51 for palmar hyperhidrosis, PH, and 51 for axillary hyperhidrosis, AH) were prospectively surveyed. They were divided into three groups according to their BMI: Group I was composed of 19 patients with BMI<20 (9 patients with PH and 10 with AH); Group II was composed of 52 patients with 20 < or =BMI<25 (25 with PH and 27 with AH); and Group III was composed of 31 patients with BMI > or =25 (17 with PH and 14 with AH). Each procedure was simultaneously and bilaterally performed under general anesthesia using two 5.5 mm trocars and a 30 degrees optic system.

Patients treated for PH (resection of T2-T3) had more severe CS than those with AH (resection of T3-T4) (p=0.007) and the greater the BMI, the greater the severity of the CS (p<0.001). No statistically significant difference was found between the BMI bands in relation to the degree of satisfaction (p=0.644), nor when we compared the degree of satisfaction to the degree of CS (p=0.316).

The greater the BMI, the more severe the CS, but this did not correlate with the patients' level of satisfaction. Avoiding the resection of T2 sympathetic ganglia is also important in reducing the intensity of CS.