Meekins A Rebecca, Siddiqui Nazema Y, Amundsen Cindy L, Kuchibhatla Maragatha, Dieter Alexis A
From the Departments of Obstetrics and Gynecology and Biostatistics and Bioinformatics, Duke University Medical Center, Durham, North Carolina, and the Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill.
South Med J. 2017 Dec;110(12):785-790. doi: 10.14423/SMJ.0000000000000733.
To evaluate the relation between voided volume and void trial "success" to create an algorithm that minimizes the need for postvoid residual volume (PVR) assessment in backfill-assisted void trials.
This article is an ancillary analysis of deidentified data from a randomized trial evaluating prophylactic antibiotics after urogynecologic surgery. Void trials were routinely performed after surgery; voided volumes, PVR, and void trial outcomes were collected. The void trial regimen was as follows: the bladder was backfilled with 300 mL of normal saline or until the patient reported the urgency to void, the catheter was removed, and the participant was prompted to void immediately. PVR volume was measured either by sonographic bladder scan or catheterization. Voided volumes were categorized in 25-mL increments from 50 to 225 mL. For each voided volume range, the PVR and void trial outcome data were incorporated to calculate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) in terms of ability of voided volume alone to predict a passing void trial result. An algorithm was created using the voided volumes that optimize PPV and NPV.
The study population included 255 participants. Voided volumes <100 mL and ≥200 mL were identified as optimal thresholds to predict failure and passage of backfill-assisted void trials, respectively. When patients voided <100 mL, 3% passed their void trial (NPV odds ratio 96.7, 95% confidence interval 88.6-99.5). When patients voided ≥200 mL, 97% passed (PPV odds ratio 97.4, 95% confidence interval 93.5-99.3).
We propose an algorithm for void trials after urogynecologic surgery. After backfilling the bladder if voided volume is ≥200 mL, the void trial is successful and no PVR is needed; if voided volume is between 100 and 199 mL, the void trial is indeterminate and PVR is recommended; and if voided volume is <100 mL, the void trial is unsuccessful and catheterization is needed. Applying this algorithm to our study population would have eliminated the need for PVR in 85% of patients. Calculated PPVs and NPVs depend on the prevalence of voiding dysfunction in the population being studied, and therefore may be unique to our institution.
评估排尿量与排尿试验“成功”之间的关系，以创建一种算法，尽量减少在回填辅助排尿试验中对残余尿量（PVR）评估的需求。
本文是对一项评估妇科泌尿手术后预防性使用抗生素的随机试验中去识别化数据的辅助分析。术后常规进行排尿试验；收集排尿量、PVR和排尿试验结果。排尿试验方案如下：用300 mL生理盐水对膀胱进行回填，或直至患者报告有排尿紧迫感，然后拔除导尿管，并促使参与者立即排尿。通过超声膀胱扫描或导尿测量PVR量。排尿量以25 mL为增量进行分类，范围从50至225 mL。对于每个排尿量范围，纳入PVR和排尿试验结果数据，以计算仅根据排尿量预测排尿试验通过结果的敏感性、特异性、阳性预测值（PPV）和阴性预测值（NPV）。使用优化PPV和NPV的排尿量创建一种算法。
研究人群包括255名参与者。排尿量<100 mL和≥200 mL分别被确定为预测回填辅助排尿试验失败和通过的最佳阈值。当患者排尿量<100 mL时，3%的患者排尿试验通过（NPV优势比96.7，95%置信区间88.6 - 99.5）。当患者排尿量≥200 mL时，97%的患者通过（PPV优势比97.4，95%置信区间93.5 - 99.3）。
我们提出了一种妇科泌尿手术后排尿试验的算法。膀胱回填后，如果排尿量≥200 mL，排尿试验成功，无需测量PVR；如果排尿量在100至199 mL之间，排尿试验结果不确定，建议测量PVR；如果排尿量<100 mL，排尿试验失败，需要导尿。将该算法应用于我们的研究人群，85%的患者将无需测量PVR。计算出的PPV和NPV取决于所研究人群中排尿功能障碍的患病率，因此可能因我们机构而异。
