Materials and Methods

We designed a retrospective cross-sectional observational study that was conducted between January 2015 and March 2020. A total of 315 patients with the diagnosis of NMIBC localized on lateral wall of the bladder were analysed at Izmir Bakircay University Cigli Training and Research Hospital Urology Department and Recep Tayyip Erdogan University Urology Department. Patients with a history of previous TUR-BT, diagnosis of non-urothelial carcinoma, coagulopathy, history of allergic reaction to the local anaesthetic agent, presence of muscle invasive bladder cancer, history of chemotherapy or radiotherapy before TUR-BT, presence of variant histopathology, use of bipolar energy for the resection of bladder tumour, presence of concomitant upper urothelial tract urothelial carcinoma, neuromuscular disease, pregnancy or history of medication affecting the immune system were excluded. Of the initial 315 patients, 209 were excluded from the study, and the remaining 106 patients were included (Fig. 1). After local ethical committee permission was received (local ethical committee number 2020/131), data from the patients with the diagnosis of NMIBC were recorded retrospectively from the hospital patient record system. Patients’ demographic characteristics, localization, largest tumour size, histopathological type of tumour, presence of recurrence and/or progression, time to recurrence from initial TUR-BT, presence of muscle tissue in the surgical specimen, inability to complete resection, death from cancer and both perioperative and postoperative complications were recorded for further statistical analyses. All TUR-BT procedures were performed using monopolar energy for the resection of the tumour with a 26 Fr Karl-Storz resectoscope under 30 degree optical vision with adjustment to 120 joules for cutting and 80 joules for coagulation. One surgeon performed the TUR-BT procedure on the patients in group 1 in Recep Tayyip Erdogan University, Urology department and one surgeon performed the TUR-BT procedure on the patients in group 2 in Izmir Bakircay University Cigli Training and Research Hospital, Urology Department. All obturator block decisions were made by the anesthesiologist when the suggestion of surgeon according to the localization of tumor. Spinal anaesthesia was performed in the operating room in a sitting position at the level of the L3–4 or L4–5 intervertebral space with a 25 gauge Quincke needle, and 10–15 mg of 2–3 ml 0.5% hyperbaric bupivacaine was administered through the needle into the subarachnoid space before the patient was repositioned to a supine position. After waiting for 10 min, and when sensorial blockade up to T10 dermatome was observed, a lithotomy position was performed. Additional obturator nerve blockade with ultrasound guidance was performed according to the localization of the tumour. First, the antero-medial side of the femur was demonstrated by a two-dimensional 38 mm, 6–13 MHz ultrasound probe (Mindray, M7, Biomedical Electronics Co., Shenzhen, China). Afterward, a high-frequency probe was placed proximal to the adductor longus muscle to determine the adductor longus, brevis and magnus muscles. When the obturator nerve was demonstrated between the muscle groups, the position of the nerve was confirmed by setting the current of the stimulator (Braun Stimuplex HNS11, B. Braun, Melsungen, Germany) to 1.5–2 mA and the duration to 0.1 ms. Under ultrasound vision, a 50 mm needle (21 gauge, 50 mm Stimuplex A, B. Braun, Melsungen, Germany) was inserted parallel to the long axis of the probe and guided to the anterior branch of the obturator nerve. After adductor contractions were observed at 0.3–0.5 mA, a maximum of 10 mL 2% lidocaine was injected through the needle. Surgery started after 10 min had passed. During the surgery, patients were monitored with non-invasive blood pressure, pulse, sPO2 intraoperative electrocardiography.
In our study, all patients underwent monopolar TUR-BT due to the presence of controversial results regarding bipolar versus monopolar techniques and strong advice to use monopolar TUR-BT in current urology guidelines (12). Patients were divided into two groups according to the anaesthesia used. While only spinal anaesthesia was performed in Group 1, spinal anaesthesia combined with ultrasound-guided obturator nerve blockade according to the localization of the tumour was performed in Group 2. The groups were compared statistically in terms of oncological outcomes. In patients with an incomplete resection, re-TUR-BT was performed 4–6 weeks after the first TUR-BT. The first follow-up was performed with all patients the third month after the initial TUR-BT, and subsequent follow-ups were performed every 3 months up to 2 years, then every 6 months up to 5 years and 1 per year after 5 years. A detailed history, physical examination, cystoscopic examination and urinary cytology were collected at each follow-up (12).
All statistical analyses were conducted using the SPSS Statistics 26.0 (IBM Inc., Armonk, NY, US) software package. Categorical variables were described by frequencies and percentages; continuous variables were described by means and standard deviations. The Kolmogorov–Smirnov test was used to evaluate the normality of the distributions, and the Mann–Whitney U test was used to compare groups and quantitative independent data. The chi-square test was used for qualitative independent data. Spearman’s correlation analysis was applied for correlation, and the Kaplan–Meier test was used to calculate survival statistics. A p -value less than 0.05 was chosen as the criterion for statistical significance.