2006 IRRIGATION FLUID ABSORPTION DURING 120W HIGH-POWER GREENLIGHT LASER VAPORIZATION OF THE PROSTATE: RESULTS FROM A PROSPECTIVE INVESTIGATION USING EXPIRED BREATH ETHANOL MEASUREMENTS

INTRODUCTION AND OBJECTIVES: Greenlight laser vaporisation (LV) of the prostate has been shown to be a safe procedure even for high-risk patients with lower urinary tract symptoms caused by prostate enlargement. Intra-operative fluid absorption was not detectable during LV using the first generation 80W greenlight laser. For the more powerful 120W greenlight laser, a different spectrum of adverse events, including a higher rate of capsular perforations and more bleeding complications, has been reported. The aim of the present investigation was to assess if fluid absorption occurs during LV using the more powerful 120W laser. METHODS: A total of 50 consecutive patients was investigated during 120W greenlight LV of the prostate. Intra-operative irrigation was performed using isotonic saline containing 1% ethanol. The breath ethanol concentration was measured every 10 min throughout the procedure with a conventional alcometer. The volume of fluid absorption was calculated from the results of these measurements. Intraoperative changes of haemoglobin, haematocrit, venous pH and serum electrolytes were also recorded. RESULTS: The median patients’ age was 69 y (range: 49-84) and the median prostate volume 41 mL (23-118). 25 patients (50%) were operated under thrombocyte aggregation inhibition and 8 (16 %) under anti-coagulation therapy. The median operation time was 70 min (30-170), the median irrigation volume 18 L (8-45) and the median applied laser energy 230 kJ (65-400). 22 patients (44 %) had a positive ethanol breath test. The median amount of fluid absorption in these patients was 1249 mL (138-3452). The surgeons reported intra-operative events in form of opened venous sinuses (n 2), capsular perforation (n 3) or a deep bladder neck incision (n 5) In 10 of these patients (45%). In the group of patients with a positive ethanol test, a significant decrease of the haemoglobin, haematocrit and venous pH and a significant increase of the serum chloride were detectable. CONCLUSIONS: Intra-operative fluid absorption was detectable in 44% of the patients undergoing 120W greenlight LV of the prostate. Absorption of isotonic saline does not result in a classical TUR-syndrome. However, care must be taken in cardiovascular highrisk patients because absorption of up to 3.5 liters of saline can result in serious complications in these patients. Intra-operative monitoring with venous pH or serum chloride might help to detect potentially dangerous fluid absorption if ethanol breath ethanol measurements are not performed.