Management of Acute and Chronic Retention in Men

Magnetic soft robotic bladder for assisted urination

The poor contractility of the detrusor muscle in underactive bladders (UABs) fails to increase the pressure inside the UAB, leading to strenuous and incomplete urination. However, existing therapeutic strategies by modulating/repairing detrusor muscles, e.g., neurostimulation and regenerative medicine, still have low efficacy and/or adverse effects. Here, we present an implantable magnetic soft robotic bladder (MRB) that can directly apply mechanical compression to the UAB to assist urination. Composed of a biocompatible elastomer composite with optimized magnetic domains, the MRB enables on-demand contraction of the UAB when actuated by magnetic fields. A representative MRB for a UAB in a porcine model is demonstrated, and MRB-assisted urination is validated by in situ computed tomography imaging after 14-day implantation. The urodynamic tests show a series of successful urination with a high pressure increase and fast urine flow. Our work paves the way for developing MRB to assist urination for humans with UABs.

Mitigation of postoperative urinary retention among total joint replacement patients using the ERAS protocol and applying risk-stratified catheterization

BACKGROUNDS

We intended to identify the incidence and risk factors (RFs) for Postoperative urinary retention (POUR) after applying a risk-stratified catheterization optimization method in enhanced recovery after surgery (ERAS)-total joint arthroplasty (TJA).

METHODS

A total of 381 patients were prospectively monitored for POUR. POUR diagnosis was done by a perioperative specialist. Data on potential risk factors (RFs) for POUR were accumulated. Univariate analysis (UA) was conducted to identify possible indicators of POUR, followed by multivariate analysis (MA) of identified indicators.

RESULTS

POUR occurred in 5.5% of cases, including 8 (3.4%) patients underwent total knee arthroplasty and 13 (10.4%) patients underwent total hip arthroplasty. In UA, age, sex, American Society of Anesthesiologists (ASA) score, and the type of operation were significantly different on UA (P = 0.046, P = 0.022, P = 0.000 and P = 0.049, respectively). Other additional predictors, including body mass index (BMI), international prostate symptom score (IPSS) score, preoperative haemoglobin (Hb), duration of operation, estimated intraoperative blood loss, intraoperative fluid volume, fluid infusion volume within 24 h postoperatively were not associated with POUR (P > 0.05). MA results demonstrated that age, ASA score, type of operation and standard intraoperative placement of an indwelling bladder catheter (SIP-IBC) were strongly associated with POUR development risk (P < 0.05).

CONCLUSION

Overall, we had a low POUR incidence in our study cohort. However, with the shift from non-ERAS TJA to ERAS TJA protocol, it is crucial to closely monitor the male gender, advanced age, THA and SIP-IBC, as these variables can markedly enhance POUR risk.

Urinary retention on an acute geriatric hospitalisation unit: prevalence, risk factors and the role of screening, an observational cohort study

PURPOSE

Urinary retention (UR) is common in older patients. The aim of this observational cohort study was to measure the prevalence of UR in patients aged ≥ 75 years on admission to an acute geriatric hospitalisation unit and to determine which at risk group would benefit from screening.

METHODS

Post-void residual volumes (PVR) were measured within 3 days of admission with an ultrasound bladder scan. Uni- and multivariable analysis were used to determine risk factors associated with PVR ≥ 150 and ≥ 300 millilitres.

RESULTS

Ninety-four patients, mean age 84.6 years, were included. The male/female ratio was 0.7. Patients with PVR ≥ 150 (29.8%) had more urological comorbidities, symptoms of overflow incontinence, voiding difficulties, subtotal voiding, faecal impaction, urinary tract infection (UTI) and were more frequently referred because of urinary symptoms. Patients with PVR ≥ 300 lived less at home, had more urological comorbidities, dysuria, voiding difficulties, subtotal voiding, constipation, faecal impaction, UTI, detrusor relaxants, and were more frequently referred because of urinary symptoms. Voiding difficulties and referral because of urinary symptoms were independently associated with PVR ≥ 150. Not living at home, reporting subtotal voiding, constipation, and referral because of urinary symptoms were independently associated with PVR ≥ 300.

CONCLUSION

Screening for UR on admission to an acute geriatric hospitalisation unit is most indicated in patients with urinary and defaecation problems. However, because the prevalence was high, because UR was also observed in patients without these problems, and history taking may be difficult, the threshold for PVR measurement in acutely ill geriatric patients should be low.

TRIAL REGISTRATION

Clinicaltrials.gov NTC04715971, January 19, 2021 (retrospectively registered).

Superficial peroneal neuromodulation of nonobstructive urinary retention in cats

AIMS

To determine if superficial peroneal nerve stimulation (SPNS) can improve nonobstructive urinary retention (NOUR).

METHODS

In α-chloralose anesthetized cats, NOUR was induced by repetitive application (4-16 times) of 30-minute tibial nerve stimulation (TNS: 5 Hz frequency, 0.2 ms pulse width) at 4 to 6 times threshold intensity (T) for inducing toe twitches. SPNS (1 Hz, 0.2 ms) at 2 to 4 times threshold intensity (T) for inducing posterior thigh muscle contractions was applied either continuously (SPNSc) during a cystometrogram (CMG) or during voiding (SPNSv) by a surgically implanted cuff electrode or by skin surface electrodes to determine if the stimulation reduced NOUR induced by prolonged TNS.

RESULTS

During control CMGs, efficient (86.4% ± 5.5%) voiding occurred with a postvoid residual (PVR) volume equal to 14.9% ± 6.2% of control bladder capacity. NOUR elicited by prolonged TNS significantly (P < .05) increased bladder capacity to 168.6% ± 15.5% of control, reduced voiding efficiency to 30.4% ± 4.8%, and increased PVR to 109% ± 9.2% of control. Using the implanted cuff electrode, SPNSc and SPNSv significantly (P < .05) increased voiding efficiency to 66.7% ± 7.4% and 65.0% ± 5.9%, respectively, and reduced PVR to 52.2% ± 11.4% and 64.3% ± 11.6%, respectively. SPNSc but not SPNSv significantly (P < .05) reduced bladder capacity to 133.4% ± 15% of control. Transcutaneous SPNSv but not SPNSc also significantly (P < .05) reversed the TNS-induced NOUR responses.

CONCLUSIONS

This study shows that SPNS is effective in reversing NOUR induced by prolonged TNS. Transcutaneous SPNS provides the opportunity to develop a noninvasive neuromodulation therapy for NOUR to treat more patients than current sacral neuromodulation therapy.

The role of clean intermittent catheterization in the treatment for detrusor underactivity

OBJECTIVE

To study the influence of clean intermittent catheterization (CIC) on the lower urinary tract function in patients with urinary retention (UR) due to detrusor underactivity (DU).

MATERIAL AND METHODS

A longitudinal study was carried out on 49 patients (28 men, 21 women) of mean age 55years, who underwent CIC for UR secondary to DU. The mean CIC frequency was 3.15 times/day. Patients' clinical data were collected, and they underwent urodynamic study before and after CIC, with a mean interval of 4years. Fisher's exact test was used for the analysis of categorical variables and Student's t test for parametric variables. The level of significance was set at 0.05 for a two-tailed test.

RESULTS

The second urodynamic study showed a significantly increased bladder compliance, the Bladder Outlet Obstruction Index (BOOI) and the Bladder Contractility Index (BCI) also increased but without reaching statistical significance. There was a significantly higher percentage of benign prostatic hyperplasia (BPH) and acontractile detrusor cases among the group of patients whose BCI improved after CIC, with significantly lower CIC time.

CONCLUSIONS

CIC improved bladder compliance in the patients of our series. The BCI improved in BPH patients and in patients with acontractile detrusor.

Prolonged nonobstructive urinary retention induced by tibial nerve stimulation in cats

Nonobstructive urinary retention (NOUR) is a medical condition without an effective drug treatment, but few basic science studies have focused on this condition. In α-chloralose-anesthetized cats, the bladder was cannulated via the dome and infused with saline to induce voiding that could occur without urethral outlet obstruction. A nerve cuff electrode was implanted for tibial nerve stimulation (TNS). The threshold (T) intensity for TNS to induce toe twitch was determined initially. Repeated (6 times) application of 30-min TNS (5 Hz, 0.2 ms, 4-6T) significantly (P < 0.05) increased bladder capacity to 180% of control and reduced the duration of the micturition contraction to 30% of control with a small decrease in contraction amplitude (80% of control), which resulted in urinary retention with a low-voiding efficiency of 30% and a large amount of residual volume equivalent to 130% of control bladder capacity. This NOUR condition persisted for >2 h after the end of repeated TNS. However, lower frequency TNS (1 Hz, 0.2 ms, 4T) applied during voiding partially reversed the NOUR by significantly (P < 0.05) increasing voiding efficiency to 60% and reducing residual volume to 70% of control bladder capacity without changing bladder capacity. These results revealed that tibial nerve afferent input can activate either an excitatory or an inhibitory central nervous system mechanism depending on afferent firing frequencies (1 vs. 5 Hz). This study established the first NOUR animal model that will be useful for basic science research aimed at developing new treatments for NOUR.

Clinical Outcome of Immediate Transurethral Surgery for Benign Prostate Obstruction Patients with Acute Urinary Retention: More Radical Resection Resulted in Better Voiding Function

Introduction: Transurethral surgery of the prostate is currently the gold standard treatment modality for patients with benign prostatic hyperplasia (BPH) with recurrent acute urinary retention. This study aimed to evaluate the outcome and predictors of patients receiving immediate surgery after acute urinary retention (AUR) episodes. Materials and Methods: From January 2016 to January 2017, we retrospectively included 714 patients who received transurethral surgery of prostate due to BPH. Among them, 158 patients received surgeries immediately after an AUR episode. General characteristics data including age, Body mass index (BMI), International prostate symptom score (IPSS score), prostate volume and Prostate-specific antigen (PSA) were reviewed. We also collected surgery-related parameters including surgical types, operation time, and specimen weight. Resection ratio was defined as (resected specimen weight)/(Transurethral ultrasound (TRUS) volume). The catheterization status on discharge, post-operative medication for BPH, and AUR within 3 months after operation were evaluated. Statistical analysis was performed with Statistical product and service solutions (SPSS). Results: The mean age of the patients was 73.5 years, with a BMI of 24 kg/m². IPSS total score was 25 with a Voiding symptom/Storage symptom score (V/S score) of 14.6 and 10.4, respectively. A total of 74 (46.8%) patients still took medication for BPH for over 1 month after the surgeries, 28 (17.7%) patients were not catheter-free at the time of discharge, and 14 (8.9%) patients had AUR within 3 months after the surgeries. Surgical type did not impact the outcome of surgeries. In patients who received Transurethral resection of the prostate (TURP), the resection ratio is the only predictor for the catheterization status on discharge and post-operative medication for BPH within 3 months after operation. Conclusions: In patients with BPH-related AUR followed by immediate transurethral surgeries, more radical resection is significantly correlated with short-term medication-free and catheter-free status.

Lower Urinary Tract Symptoms, Benign Prostatic Hyperplasia, and Urinary Retention

Lower urinary tract symptoms (LUTS) consist of a common set of urologic symptoms that can affect the elderly. The prevalence of LUTS is expected to rise owing to the continued increase of numbers of the elderly. Although benign prostatic hyperplasia is considered a common cause of LUTS, the broader potential causes of LUTS are myriad. A wide range of diagnostic modalities and treatments are available to manage patients with LUTS and their utilization should not be limited to the urologist.

Non-neurogenic Chronic Urinary Retention: What Are We Treating?

PURPOSE OF REVIEW

This review examines current terminology used to define non-neurogenic chronic urinary retention (CUR), describes the pathophysiology of urinary retention, and highlights contemporary diagnostic and treatment algorithms.

RECENT FINDINGS

There is no standardized definition for the condition, but volumes >300 ml are commonly used to describe CUR. It is a clinical diagnosis which does not require urodynamics. Pathophysiologic causes of CUR be from myogenic, neurogenic, bladder outlet obstruction, or a combination of these sources. Treatment algorithms recommend stratifying patients with chronic urinary retention by risk and by symptoms before initiating treatment. Common CUR outcome endpoints need to be better utilized so that treatment modalities can be compared. Non-neurogenic CUR is a heterogeneous condition that has multiple definitions, underlying physiologies, and possible endpoints. Standardization is needed to better understand and treat CUR.

AUA White Paper on Nonneurogenic Chronic Urinary Retention: Consensus Definition, Treatment Algorithm, and Outcome End Points

PURPOSE

The AUA (American Urological Association) QIPS (Quality Improvement and Patient Safety) committee created a white paper on the diagnosis and management of nonneurogenic chronic urinary retention.

MATERIALS AND METHODS

Recommendations for the white paper were based on a review of the literature and consensus expert opinion from the workgroup.

RESULTS

The workgroup defined nonneurogenic chronic urinary retention as an elevated post-void residual of greater than 300 mL that persisted for at least 6 months and documented on 2 or more separate occasions. It is proposed that chronic urinary retention should be categorized by risk (high vs low) and symptomatology (symptomatic versus asymptomatic). High risk chronic urinary retention was defined as hydronephrosis on imaging, stage 3 chronic kidney disease or recurrent culture proven urinary tract infection or urosepsis. Symptomatic chronic urinary retention was defined as subjectively moderate to severe urinary symptoms impacting quality of life and/or a recent history of catheterization. A treatment algorithm was developed predicated on stratifying patients with chronic urinary retention first by risk and then by symptoms. The proposed 4 primary outcomes that should be assessed to determine effectiveness of retention treatment are 1) symptom improvement, 2) risk reduction, 3) successful trial of voiding without catheterization, and 4) stability of symptoms and risk over time.

CONCLUSIONS

Defining and categorizing nonneurogenic chronic urinary retention, creating a treatment algorithm and proposing treatment end points will hopefully spur comparative research that will ultimately lead to a better understanding of this challenging condition.

Teaching of intermittent self-catheterisation through dedicated nurse-led TOV clinic for patients with uncomplicated acute urinary retention: How useful is it in practice?

Objectives:

Acute urinary retention (AUR) is a common urological emergency. Our institution has established an outpatient pathway for managing patients with uncomplicated AUR on discharge from A&E: with catheter education and alpha-blocker therapy. They are followed up in a nurse-led clinic where intermittent self-catheterisation (ISC) can be taught if required. The aim of this study is to investigate the outcomes of our nurse-led trial of void (TOV) clinic and specifically the merit of teaching ISC.

Methods:

Data was prospectively collected and analysed for all patients with AUR who were followed up in the nurse-led TOV clinic between October 2012 and December 2014.

Results:

Over 26 months, 120 men with AUR attended the TOV clinic with an average age of 71 years (range 28–94 years). Forty-nine of 120 (41%) patients had an identifiable cause for AUR (UTI=13, constipation=13, alcohol=11, anti-cholinergics=7, post-operative=4 and post-brachytherapy=1). Sixty-four men passed and 50 failed TOV. Six were excluded from this analysis as they did not proceed to TOV in clinic (three requested LTC and three were not appropriate for outpatient clinic). All 50 patients who failed TOV were offered ISC. Thirty-two of 50 patients (64%) learnt ISC. Ten declined and eight were unable to perform ISC. Only seven of 50 patients (14%) went on to have a TURP, four of whom had declined to learn ISC. Of the remaining 43 patients, 24 (56%) had return of spontaneous voiding.

Conclusion:

In our experience, a pathway for reviewing AUR patients in a nurse-led TOV clinic where expertise for ISC tuition is available is extremely useful. In our series, only 14% of patients who failed TOV required TURP. Bladder function often returns to normal over time but ISC offers patients an autonomous management option if satisfactory to themselves whilst avoiding the complications of LTC.

Altered distribution of interstitial cells and innervation in the rat urinary bladder following spinal cord injury

Changes in the distribution of interstitial cells (IC) are reportedly associated with dysfunctional bladder. This study investigated whether spinal cord injury (SCI) resulted in changes to IC subpopulations (vimentin-positive with the ultrastructural profile of IC), smooth muscle and nerves within the bladder wall and correlated cellular remodelling with functional properties. Bladders from SCI (T8/9 transection) and sham-operated rats 5 weeks post-injury were used for ex vivo pressure–volume experiments or processed for morphological analysis with transmission electron microscopy (TEM) and light/confocal microscopy. Pressure-volume relationships revealed low-pressure, hypercompliance in SCI bladders indicative of decompensation. Extensive networks of vimentin-positive IC were typical in sham lamina propria and detrusor but were markedly reduced post-SCI; semi-quantitative analysis showed significant reduction. Nerves labelled with anti-neurofilament and anti-vAChT were notably decreased post-SCI. TEM revealed lamina propria IC and detrusor IC which formed close synaptic-like contacts with vesicle-containing nerve varicosities in shams. Lamina propria and detrusor IC were ultrastructurally damaged post-SCI with retracted/lost cell processes and were adjacent to areas of cellular debris and neuronal degradation. Smooth muscle hypertrophy was common to SCI tissues. In conclusion, IC populations in bladder wall were decreased 5 weeks post-SCI, accompanied with reduced innervation, smooth muscle hypertrophy and increased compliance. These novel findings indicate that bladder wall remodelling post-SCI affects the integrity of interactions between smooth muscle, nerves and IC, with compromised IC populations. Correlation between IC reduction and a hypercompliant phenotype suggests that disruption to bladder IC contribute to pathophysiological processes underpinning the dysfunctional SCI bladder.

Evaluation of the clinical value of a simple flowmeter in the management of male lower urinary tract symptoms

Study Type - Diagnostic (exploratory cohort) Level of Evidence 3b What's known on the subject? and What does the study add? Electronic uroflowmetry reasonably predicts the likelihood of bladder outlet obstruction (BOO) and risk of AUR. This low-cost device, Uflowmeter(™) , allows men to perform uroflowmetry at home with ease and the results are compatible with that of electronic uroflowmentry. It can also estimates risk of AUR and the need for TURP to relieve LUTS.

OBJECTIVE

To show the clinical value of a simple flowmeter, which has been devised to measure uroflow on an ordinal scale (<10, 10-15, 15-19 and >19 mL/s) at home, for the management of male lower urinary tract symptoms (LUTS).

PATIENTS AND METHODS

A total of 186 men with LUTS were enrolled in the study. The mean (range) follow-up was 220 (68-431) days. The men's mean (range) age was 65.5 (46-83) years, mean (range) maximum urinary flow rate (Qmax) 12.8 (4.3-39.5) mL/s, mean (range) voided volume 294.8 (151-686) mL; mean (range) postvoid residual urine volume (PVR) 50 (0-303) mL and mean (range) International Prostate Symptom Score (IPSS) 13.5 (1-31). The men underwent electronic uroflowmetry ('clinic uroflowmetry') and completed an IPSS questionnaire in the clinic. They then conducted 10 measurements with the device at home ('home uroflowetry'). The uroflowmetry and IPSS questionnaire were repeated 2 weeks later. Quadratically weighted Kappa analysis (κ) of the home uroflowmetry vs. clinic uroflowmetry, and of the sensitivity and specificity of the home uroflowmetry values to correspond to the mean Qmax of clinic uroflowmetry (<10, 10-15, 15-19 and >19 mL/s) was performed. Similar analyses were performed for the IPSS. Kaplan-Meier analysis was performed to evaluate whether home uroflowmetry was able to prognosticate acute urinary retention (AUR) or the need for transurethral resection of the prostate (TURP).

RESULTS

The home uroflowmetry values (κ= 0.84, 95% confidence interval [CI]: 0.78-0.90) were superior to the IPSS (κ= 0.083; 95% CI: 0-0.173) in correlating with the mean Qmax of clinic uroflowmetry. Home uroflowmetry was most sensitive in identifying a mean Qmax of >19 mL/s (sensitivity: 0.99; 95% CI:0.97-1.00) and most specific in identifying a mean Qmax of <10 mL/s (specificity: 0.90; 95% CI:0.83-0.94). The home uroflowmetry works best in ruling out a mean Qmax of <19 mL/s (diagnostic odds ratio [DOR]= 349.3; 95% CI:40.24-3037.7), followed by a mean Qmax of <15 mL/s (DOR = 91.02; 95% CI:31.23-265.23) and a mean Qmax of <10 mL/s (DOR = 32.04; 95% CI:14.0-73.19). Men with a home uroflowmetry value ≤10 mL/s were more likely (n= 6; 8.8%) than those with a home uroflowmetry value >10 mL/s (n= 2; 1.7%) to develop AUR or require TURP (log-rank test: P= 0.017; hazard ratio:5.61(95% CI:1.10-28.64)). The IPSS failed to display the same discriminative capability.

CONCLUSION

Home uroflowmetry using this simple device is a satisfactory estimation of clinic uroflowmetry using an electronic flowmeter and can predict the significant progression of male LUTS.