Coagulating intermittent cutting - Improved high-frequency surgery in transurethral prostatectomy

Objectives: Transurethral prostatectomy (TURP) is the gold standard in surg ical therapy of symptomatic bladder outlet obstruction. TURP is characteris ed by immediate treatment success, due to the removal of obstruction combin ed with a long-lasting improvement of symptoms and voiding parameters. In s pite of good long-term results of TURP, intraoperative blood loss produces morbidity. We investigated a blood-sparing cut using a new high-frequency t echnology. Methods: (1) A standard high frequency generator was extended in its functi on by additional electronics. (2) The possibility of a blood-sparing cut us ing 'coagulating intermittent cutting' (CIC cocut BMP) was quantified ex vi vo using a blood-perfused porcine kidney. Four cuts next to each other were performed through the parenchyma using a standard resectoscope with a stan dard loop. This was done with a commercially available generator and CIC co cut BMP. The blood loss was determined semiqantitatively. Results: (1) In a first step 'coagulating cutting' with coagulating and cut ting periods (10/94-08/96) was developed. During each cut, phases with pred ominant cutting effect alternate with coagulating phases of defined duratio n. As a disadvantage, operation time increased due to lower cutting speed. In a second step cutting combined with coagulation effect with high voltage pulses - 'coagulating intermittent cutting' (08/96-06/97) - was developped . In this technique, the output signal consists of a pulse-modulated sinuso idal voltage with high amplitudes, But gas bubbles impaired vision. This fi nally resulted in the 'coagulating intermittent cutting' with constant volt age pulses and control of pulse intervals (CIC cocut BMP, since 07/97 up to now). (2) Comparing the function of the high-frequency generators in vitro , the Wilcoxon test for paired samples revealed a significant reduction of the observed bleeding with the CIC cocut BMP (p = 0.002). Conclusions: 'Coagulating intermittent cutting' improves the gold standard of TURP with reduced blood loss. The procedure is feasible with a standard resection equipment. The already trained surgeon has no further learning cu re, and teaching of classical TURP is maintained. Copyright (C) 2001 S. Kar ger AG, Basel.