Transurethral resection of bladder cancer on the lateral bladder wall without obturator nerve block: extent of adductor spasms using the monopolar versus bipolar technique-a prospective randomised study.

PURPOSE: To establish whether bipolar transurethral resection of tumours (bTURB) on the lateral bladder wall is superior to monopolar transurethral resection (mTURB) of such tumours. To our knowledge, this is the first prospective randomised study, which defines complete resection depending on obturator jerk as primary endpoint.

METHODS: In a prospective, randomised, single centre study, 52 patients with newly diagnosed or recurrent bladder tumour on the lateral bladder wall were enrolled and randomised to undergo mTURB or bTURB; 44 patients were eligible for analysis, of whom 21 underwent mTURB and 23 bTURB. Any differences between the two techniques related to the incidence of unwanted stimulation of the obturator nerve and subsequent adductor spasms were evaluated. All procedures were carried out under laryngeal mask anaesthesia without obturator nerve block (ONB) and without drug-induced relaxation.

RESULTS: Baseline characteristics of the two study groups did not differ statistically significantly. The success rate defined as complete resection of the bladder tumour without any clinically relevant adductor spasm was 61.9% in the monopolar group and 82.6% in the bipolar group (p = 0.18).

CONCLUSIONS: Complete, undisturbed resection of tumours of the lateral bladder wall is feasible with mTURB and bTURB. Adductor spasms due to obturator jerk can occur suddenly with the risk of bladder perforation. We therefore support ONB when using spinal anaesthesia and drug-induced relaxation when using general anaesthesia when performing TURB on the lateral bladder wall.