Continuous versus intermittent flow irrigation in transurethral resection of the prostate.

OBJECTIVE: We compared fluid absorption, blood loss, and immediate postoperative complications in transurethral resection of the prostate (TURP) performed with the continuous flow and the intermittent flow irrigation techniques. We also studied pressure conditions under which fluid absorption occurs when continuous flow irrigation is used. METHODS: One experienced urologic surgeon performed TURP in 40 patients using suprapubic drainage of the bladder and in 40 other patients using the intermittent-filling technique. Fluid absorption was measured by the ethanol method every ten minutes. The intravesical pressure was recorded continuously in 23 of the patients with suprapubic drainage. RESULTS: Fluid absorption was more common when suprapubic drainage was used (P < 0.004). There were no differences in operating time, blood loss, postoperative complications, or in the period of hospitalization. Low-degree absorption occurred during minor elevations of the intravesical pressure, and massive fluid absorption was associated with pressures between 1.0 and 2.5 kPa (10 and 25 cm H2O). CONCLUSIONS: Continuous flow irrigation promoted fluid absorption, which occurred at lower pressures than commonly believed. With respect to other parameters, we found no superiority of one irrigating technique over the other.