Accuracy of postvoid residual volumes after vaginal delivery: a prospective equivalence study to compare an automatic scanning device with transurethral catheterization

Post-void residual measurement: A comprehensive review of the clinical relevance and precision of bladder scanner devices

OBJECTIVE

To evaluate the accuracy of bladder scanners in measuring bladder volume and to compare their precision.

METHOD

MEDLINE and Cochrane databases were searched from January 1, 1990 to December 30th, 2023. We selected studies assessing results of bladder volume measurement using bladder scanners, standard ultrasonography or bladder catheterization.

RESULTS

In total, 177 studies were screened, of which 22 were included in the final analysis. According to the literature, there is no clinically significant difference in the measurement of bladder volume using urethro-vesical catheterization, bladder scanner, or conventional ultrasound. Studies comparing different types of bladder scanners did not show any difference in accuracy.

CONCLUSIONS

Bladder scanners are precise tools to evaluate bladder volume in urological patients, applicable in daily practice. Knowledge of the patient's medical history is crucial to better interpret the measurement.

Agreement and Reliability of Patient-measured Postvoid Residual Bladder Volumes

OBJECTIVE

To assess the reliability, agreement with provider measurement, and patient preferences regarding patient self-measurement of postvoid residual bladder volume (PVR). PVR measurement in the nonhealthcare setting is a valuable opportunity for remote monitoring of voiding dysfunction patients. We hypothesized that patient self-measurement of PVR using a smart-device portable ultrasound system with artificial intelligence would demonstrate high reliability, strong agreement with provider measurement, and be preferred over provider measurements.

METHODS

Patients were enrolled during outpatient Urology visits. PVRs were measured in triplicate by providers using each of the following: an FDA-cleared (standard) bladder scanner, the portable ultrasound probe using ultrasound images (Butterfly US image mode), and the portable ultrasound probe using abstract images (Butterfly abstract mode). Subjects self-measured PVRs in triplicate using both imaging modes and reported their experiences via questionnaire. Reliability was assessed via intraclass correlation. Agreement between methods was assessed via Bland-Altman analyses using a clinically acceptable difference threshold of 50 mL.

RESULTS

Fifty patients were enrolled. Intraclass correlations ranged from 0.95 to 0.98 for each method. 95% limits of agreement between standard bladder scanner and patient self-measurement were - 71.73 mL and 86.73 mL using Butterfly US image mode and - 93.84 mL and 112.52 mL using Butterfly abstract mode, respectively. Most patients preferred self-measurement over provider measurement (74% vs 26%, respectively).

CONCLUSION

Patient self-measurement of PVR using smart-device integrated portable ultrasound probes is feasible, reliable, and preferred by patients. Limits of agreement between patient self-measurement and standard bladder scanner measurements exceeded our clinically acceptable difference threshold, though the inherent error of ultrasound-based bladder volume measurements should be considered. Longitudinal PVR assessments in nonhealthcare settings may facilitate remote monitoring of voiding dysfunction patients.

Accuracy of Bladder Scanner in Measuring Bladder Volumes in Postpartum Women

IMPORTANCE

Ultrasound bladder scanners may provide a less invasive method to measure postpartum urinary volume, but their accuracy must be validated.

OBJECTIVE

The objective of this study was to evaluate the accuracy of a bladder scanner in measuring bladder volumes in postpartum women. The secondary objective was to evaluate the effect of obesity on scanner accuracy.

STUDY DESIGN

This prospective cohort study included women older than 18 years who gave birth vaginally at term gestation. After delivery, we obtained 3 sequential measurements of the bladder volume using an ultrasound bladder scanner. We then measured true bladder volume by transurethral catheterization. The primary outcome was the absolute difference between the bladder scanner volume and the catheterized volume. A Wilcoxon signed-rank test was used to compare absolute median difference between the bladder scan volume and true catheter volume. Repeated-measures analysis of variance and linear regression were used to evaluate the effect of obesity on the accuracy of the bladder scanner.

RESULTS

We enrolled 70 patients (61.4% nulliparous, 38.6% multiparous). One delivery was vacuum-assisted, 4 were forceps-assisted, and 65 were spontaneous vaginal. The median age was 34 years, and median body mass index was 30.5. Median difference between bladder scanner and catheter volume was 42.7 mL (P < 0.001), with the scanner underestimating true volume 82.9% of the time. The scanner was less accurate in patients with a body mass index ≥ 30 (P = 0.001).

CONCLUSIONS

The bladder scanner is less accurate than catheterized urine volume. However, the median difference between the bladder scanner and the catheterized volume is 42.7 mL, making it suitable for clinical use. Accuracy deteriorates in obese patients.

An International Continence Society (ICS)/ International Urogynecological Association (IUGA) joint report on the terminology for the assessment and management of obstetric pelvic floor disorders

AIMS

The terminology of obstetric pelvic floor disorders should be defined and reported as part of a wider clinically oriented consensus.

METHODS

This Report combines the input of members of two International Organizations, the International Continence Society (ICS) and the International Urogynecological Association (IUGA). The process was supported by external referees. Appropriate clinical categories and a sub-classification were developed to give coding to definitions. An extensive process of 12 main rounds of internal and 2 rounds of external review was involved to exhaustively examine each definition, with decision-making by consensus.

RESULTS

A terminology report for obstetric pelvic floor disorders, encompassing 357 separate definitions, has been developed. It is clinically-based with the most common diagnoses defined. Clarity and user-friendliness have been key aims to make it usable by different specialty groups and disciplines involved in the study and management of pregnancy, childbirth and female pelvic floor disorders. Clinical assessment, investigations, diagnosis, conservative and surgical treatments are major components. Illustrations have been included to supplement and clarify the text. Emerging concepts, in use in the literature and offering further research potential but requiring further validation, have been included as an Appendix. As with similar reports, interval (5-10 year) review is anticipated to maintain relevance of the document and ensure it remains as widely applicable as possible.

CONCLUSION

A consensus-based Terminology Report for obstetric pelvic floor disorders has been produced to support clinical practice and research.

Postpartum urinary retention after the institution of a universal voiding protocol

OBJECTIVE

Postpartum urinary retention is a frequently occurring condition for which screening is not typically a standardized part of postpartum care. The aim of this study was to determine the incidence of and risk factors for postpartum urinary retention after the introduction of a universal postpartum voiding protocol.

METHODS

This was a single-center retrospective case-control study of women delivering in a 12-month period. Women with a documented diagnosis of postpartum urinary retention per the institution's voiding protocol were classified as cases, and a matched sample of those without urinary retention were controls. Demographic and obstetric characteristics were compared between both groups using univariate and multivariate analyses as a means to identify risk factors for postpartum urinary retention.

RESULTS

8992 women were studied during the time period examined; 195 (2.2%) were identified to have postpartum urinary retention. On multivariate logistic regression analysis, operative vaginal delivery (aOR 2.98 95% CI 1.32-6.70) and second-degree or greater perineal laceration (aOR 2.83 CI 1.59-5.04) were significantly associated with postpartum urinary retention.

CONCLUSIONS

The incidence of postpartum urinary retention with a postpartum voiding protocol in place was low. Risk factors identified for urinary retention included operative vaginal delivery and second degree or greater perineal laceration. Awareness of these risk factors and implementation of standardized voiding protocols may aid with the early identification and prevention of postpartum urinary retention.

Prevalence of urinary retention after vaginal delivery: a systematic review and meta- analysis

INTRODUCTION AND HYPOTHESIS

Postpartum urinary retention requires timely detection and intervention as late detection can lead to long-term voiding dysfunction; however, trends in the prevalence of urinary retention during the postpartum period remain unclear. This systematic review and meta-analysis aimed to estimate the pooled overall prevalence of overt and covert urinary retention in women after vaginal delivery and the difference in prevalence within 4 days after delivery.

METHODS

MEDLINE, CINAHL, Ichu-shi web, and J-stage databases were searched up until October 2020. Two researchers screened and included observational studies reporting the prevalence of urinary retention up to 4 days postpartum based on inclusion criteria. The overall prevalence of overt and covert urinary retention was calculated.

RESULTS

From 24 studies, the overall overt and covert urinary retention prevalence rates were estimated to be 1% and 13%, respectively. The prevalence of overt urinary retention over time was 2% at 6 h postpartum, 1% at 6-12 h, and 3% from postpartum to 24 h postpartum. The prevalence of covert urinary retention over time was 19% (6 h postpartum), 15% (24 h postpartum), 11% (1 day postpartum), 7% (2 days postpartum), 8% (3 days postpartum), and 0.1% (4 days postpartum).

CONCLUSIONS

By postpartum day 4 after vaginal delivery, 14% of women were found to have experienced urinary retention. The highest prevalence was observed at 6 h postpartum, suggesting that urinary retention could be identified at 6 h postpartum.

Postpartum urinary retention: what are the sequelae? A long-term study and review of the literature

INTRODUCTION AND HYPOTHESIS

Postpartum urinary retention (PUR) may cause long-term urogenital tract morbidity. The incidence ranges from 0.18 to 14.6%, but the importance of prompt diagnosis and appropriate management is often underappreciated. The paucity of data on long-term outcome after PUR contributes to these drawbacks. The aim of this study was to assess long-term persistence of elevated PVR (post-void residual urine) volume after PUR. Pathophysiology, risk factors and management of PUR are reviewed.

METHODS

In our tertiary referral urogynecology unit in the University Women's Hospital of Bern, Switzerland, all patients who were referred for PUR were asked to participate in this study. PVR was measured sonographically every 2 days until day 15, then after 6, 12, 24 and 36 months and, if increased, the patients were instructed to perform clean intermittent self-catheterization. If retention persisted longer than the lactation period, multichannel urodynamics was performed.

RESULTS

Sixty-two patients were included. The median PVR normalized at day 7. Long-term voiding disorders were found in 8.2%, 6.7%, and 4.9% after 1, 2, and 3 years respectively. Multichannel urodynamics confirmed in all patients with persisting retention an acontractile detrusor and de novo stress urinary incontinence in 4 cases. Quantile regression did not reveal any factor contributing to earlier recovery. Eighty-nine percent of the patients with PUR had operative vaginal deliveries, emphasizing the importance of this risk factor for PUR.

CONCLUSIONS

In most cases PUR resolves early, but voiding difficulties persist more often than previously thought, and for these patients the consequences are devastating. Obstetric awareness, early active management, and developing management strategies in the postpartum period might preclude lower urinary tract morbidity.

Recommendations and future research initiative to optimize bladder management in pregnancy and childbirth International Consultation on Incontinence - Research society 2018

With increasing birth rates globally, obstetric bladder care and long term pelvic floor dysfunction continues to be a issue. This paper aims to provide an overview of the concerns in the antenatal, intrapartum an post partum periods and presents recommendation for the research requirements necessary and education to challenge current practice.

Three-dimensional bladder ultrasonography with the BladderScan® overestimates post void residual one week after delivery

Objective

Postpartum urinary retention is a frequent complication after childbirth. It is usually a temporary condition. However, unrecognised urinary retention can lead to considerable morbidity due to bladder over distention, detrusor atony and long term voiding dysfunction. In our clinic we noticed an overestimation of post void residual measured with the BladderScan^® in comparison with catheterization in women one week after delivery.

Study design

We included 25 women in this prospective pilot study. These women had a urinary retention over 1000 ml within 4-5 h postpartum. Conform our local protocol, an indwelling catheter was inserted for one week. After removal of the indwelling catheter, a micturition trial was conducted. The post void residual was first measured with BladderScan^® (BVI 3000), directly followed by clean intermittent catheterization which is the golden standard at this moment.

Results

There was a significant mean difference in post void residual measurements with the BladderScan^® and catheterization of 312 ml (95% CI 220-404 ml) (p < 0.001). According to our post void residual definition of 200 ml, the sensitivity and specificity of the BladderScan^® was respectively 100% and 17.6%. The positive predictive value was 36%.

Conclusion

The BladderScan^® (BVI 3000) is a non-reliable instrument to measure post void residual one week postpartum. For now clean intermittent catherization remains the golden standard.

Validity of bladder volume measurement by ultrasound in women postpartum

INTRODUCTION

Vaginal birth increases the risk of urinary retention and overdistention of the bladder. To avoid unnecessary discomfort by catheterization, it is preferable to use ultrasound for diagnosis of these conditions. The aim of this study was to determine the validity of transabdominal ultrasound and a portable ultrasound system, Biocon-700, to measure bladder volume in women postpartum.

METHODS

Fifty women were included in this method comparison study. Within 48 h of giving birth, their bladder volume was measured in randomized order with both transabdominal ultrasound and Biocon-700. After urination, participants were scanned with Biocon-700 to measure residual bladder volume, and finally the bladder was emptied by catheterization. The total bladder volume was calculated as the voided volume plus the catheterized volume.

RESULTS

Biocon-700 measured 43.4 ml ± 117.4 ml (mean ± SD) lower than the total bladder volume, while volumes measured by transabdominal ultrasound were 117.8 ml ± 110.0 ml (mean ± SD) lower. Linear regression showed significant proportional bias in both methods. The Biocon-700 could detect a residual bladder volume > 150 ml with a positive predictive value of 66.7% and a negative predictive value of 100%.

CONCLUSIONS

Neither transabdominal ultrasound nor the portable ultrasound system, Biocon-700, can be used to measure bladder volume precisely after vaginal delivery. However, both ultrasound methods can be used as screening tools to prevent overdistention of the bladder, and Biocon-700 can furthermore be used to screen women for a residual bladder volume > 150 ml.