Near-sitting position and two-lung ventilation for endoscopic transthoracic sympathectomy

Abstract

To control for hypoxemia during endoscopic transthoracic sympathectomy, usually by using double-lumen tube and one-lung ventilation, a different anesthetic technique was adopted. A prospective clinical study. A university-affiliated medical center. Twenty-one adult patients (10 male and 11 female) between 15 and 44 years of age (mean, 22 years), ASA (American Society of Anesthesiologists) physical status I and II, participated in the study. Under general anesthesia, a single-lumen endotracheal tube was inserted. The radial artery was cannulated for blood pressure monitoring and blood gas sampling. Patients were gradually raised from a supine position to 60 to 70 degrees from the horizontal plane. Mean fractional inspiratory O2 ratio was 0.4 +/- 0.02 (mixture of O2 and air) throughout the operation. Blood gas samples were taken during two-lung ventilation before surgery, at each one-chest operation, and when switching between the operated chest sides. An artificial pneumothorax was established by insufflation of CO2, the sympathetic chain coagulated, the pneumothorax released, and the lung reinflated. Comparisons were performed using one-way analysis of variance and the Bonferroni post-test. Arterial O2 partial pressure at right- and left-chest operation were 209 +/- 83 and 189 +/- 63 mmHg, respectively, compared with 227 +/- 43 and 241 +/- 69 mmHg on two-lung ventilation before and during surgery, respectively. O2 saturation, arterial CO2 partial pressure, bicarbonate, base excess, peak inspiratory pressure, and hemodynamic parameters (in most patients) did not change throughout the operation. The near-sitting position, a single-lumen tube, and a continuous two-lung ventilation technique is simple and may prevent hypoxemia during endoscopic transthoracic sympathectomy.