Perfusion Index: An Indicator of Success During Endoscopic Thoracic Sympathectomy for Hyperhidrosis
Eric I-Hun Jeng1, Nikolaus Gravenstein2, Charles T Klodell3
1Division of Thoracic and Cardiovascular Surgery, University of Florida, Gainesville, Florida.
Background:
Endoscopic thoracic sympathectomy (ETS) is indicated for refractory hyperhidrosis. The pulse oximetry-derived perfusion index (PI) quantifies pulsatile blood flow at the oximeter. Thoracic sympathectomy increases blood flow; thus we postulate it will reliably increase PI. We evaluated the ipsilateral finger PI as a predictor of successful sympathectomy during ETS.
Methods:
After institutional review board approval and informed consent, 100 adult patients undergoing bilateral ETS were studied. Finger and earlobe pulse oximetry probes were placed. Hemodynamic variables and PI were continuously monitored. PI data were collected before and every minute after sympathectomy for 5 minutes and then at 10 minutes. We defined a successful sympathectomy by at least a 50% increase of the PI on the ipsilateral arm. A repeated measures analysis of variance was conducted to determine overall model significance (p ≤ 0.05).
Results:
Left sympathectomy was associated with a mean 240% increase in PI (p < 0.0001) during the first consecutive 10 minutes, whereas the right side exhibited a mean 236% increase in PI (p < 0.0001). Statistically significant differences were observed between the mean baseline PI value ± the standard error of the mean and time intervals (1, 2, 3, 4, 5, and 10 minutes after baseline) on both the left and right sides for all time intervals. The hemodynamics remained constant throughout the study period. All patients had postoperative resolution of their hyperhidrosis symptoms.
Conclusions:
In patients with hyperhidrosis of the upper extremities, intraoperative PI derived from an ipsilateral finger pulse oximeter is an intraoperative marker for successful thoracic sympathectomy.
