Diagnostic Accuracy of Intraoperative Void Score in Predicting Catheter Free Status in Patients Undergoing Transurethral Resection of the Prostate (TURP)

Abstract

Objective: To analyze the accuracy of diagnosis and inter-observer reliability of the intraoperative void score in predicting the catheter-free status after TURP.

Methodology: The prospective study on diagnostic accuracy was a diagnostic accuracy study that was carried out in the Department of Urology, Sindh Institute of Urology and Transplantation, during a period of six months. One hundred and seventeen men aged ≥50 years with benign prostatic hyperplasia who received TURP were recruited through consecutive sampling. The intraoperative void score was measured right after the resection through the application of standardized suprapubic pressure (50 N) and the rating of the urinary stream. The scoring was done by two independent assessors. Success in the study was a trial without a catheter (TWOC) on days 3-5 post-operation and a post-void urine of less than 100 mL and no re-catheterization. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), overall accuracy, 95% confidence intervals, and Cohen's kappa were determined.

Results: Among 117 patients, 71 (60.7%) patients managed to have their catheter-free voiding, and 46 (39.3%) patients failed TWOC. The intraoperative void score was able to point out 58 true positives, 46 true negatives, 13 false negatives, and no false positives. The sensitivity was 81.7%; specificity, 100%; PPV, 100%; NPV, 78.0, and general diagnostic accuracy, 88.9%. Inter-rater reliability was high (0.81), which means that there was near-perfection.

Conclusion: Intraoperative void score is a very specific, reliable, and practical predictor of catheter-free voiding after TURP. Its simplicity to use and its good diagnostic capability justify its application in the routine perioperative assessment to inform the early postoperative management.

Keywords: Benign Prostatic Hyperplasia (BPH), Catheter-Free Voiding, Intraoperative Void Score, Transurethral Resection of the Prostate (TURP), Trial Without Catheter (TWOC)