Use of expired breath ethanol measurements in evaluation of irrigant absorption during high-power potassium titanyl phosphate laser vaporization of prostate

Abstract

Objectives To evaluate formally the risk and levels of irrigant absorption during high-power potassium titanyl phosphate (KTP) laser vaporization of the prostate by the Greenlight PV system using the expired breath ethanol technique. Methods Forty consecutive patients underwent laser vaporization of the prostate. Of these patients, 17 had a preoperative transrectal ultrasound estimation of the prostate volume (mean 97 cm 3). All procedures were performed under general anesthesia, by either of two consultants or a trainee. A 1% ethanol solution was used as irrigation fluid. Throughout the operation, the expired breath was analyzed for ethanol using a standard alcometer “plumbed” into the anesthetic circuit. Venous blood samples were taken immediately before and after the procedure for measurements of serum sodium and plasma alcohol levels. Results On average, 155,000 J of laser energy was delivered in 47 minutes. In all patients and on all occasions, the expired breath ethanol remained at 0. No statistically significant change was found in the serum sodium concentration during the procedure ( P = 0.42), and no patient displayed any clinical evidence of transurethral resection syndrome. Conclusions The results of this study have confirmed, for the first time, the lack of significant absorption of irrigation fluid during high-power KTP vaporization of the prostate using a recognized sensitive technique and the safety of using sterile water as that irrigant. This was the case even in those patients with very large prostates who are usually considered at high risk of experiencing the clinical consequences of fluid absorption during transurethral resection of the prostate and regardless of the experience of the surgeon.