Ambulatory surgery patients may be discharged before voiding after short-acting spinal and epidural anesthesia

BACKGROUND: Voiding before discharge is usually required after outpatient epidural or spinal anesthesia because of concern about bladder overdistention and dysfunction. Shorter duration spinal and epidural anesthesia may allow return of bladder function before overdistention occurs in low-risk patients (those younger than age 70, not having hernia, rectal, or urologic surgery, and without a history of voiding difficulty), and predischarge voiding may not be necessary. METHODS: After institutional review board approval and informed consent, 201 low-risk ambulatory patients were prospectively studied in either a standard or accelerated pathway after undergoing spinal or epidural anesthesia with procaine, lidocaine, 2-chloroprocaine, or less than 7 mg bupivacaine; epinephrine was not used in any anesthetic. Standard pathway patients (n = 70) were required to void before discharge. Accelerated pathway (n = 131) patients were not required to void. (After randomization of an initial 163 patients to one of the two tracks, 38 additional patients were assigned to the accelerated pathway.) If accelerated pathway patients voided, they were discharged when all other discharge criteria were met. If they did not spontaneously void after block resolution, a bladder ultrasound (BUS) was performed. If the BUS indicated a urine volume of less than 400 ml, the patients were discharged and instructed to return to the emergency department if they were unable to void within 8 h of discharge. If the BUS indicated a urine volume of greater than 400 ml, the patients were reassessed in 1 h and were discharged if they could void spontaneously. If they could not void spontaneously, they were catheterized to facilitate discharge. All patients were contacted the next day to assess the return of normal bladder function. RESULTS: All standard pathway patients voided without difficulty, and were discharged in 153 +/- 49 (SD) min. 62 patients in the accelerated pathway voided spontaneously after resolution of their block and were discharged in 127 +/- 41 min. 46 patients were discharged with a BUS less than 400 ml in 120 +/- 42 min. 23 patients had a BUS greater than 400 ml: of these, 20 patients voided within an hour and were discharged in 162 +/- 45 min. Three were catheterized after 1 h, and were discharged in 186 +/- 61 min. Mean discharge time for all patients in the accelerated pathway was 22 min shorter than the standard pathway (P = 0.002). No patients had difficulty voiding or returned to the hospital for urinary problems. None reported new urologic symptoms. CONCLUSIONS: Delay of discharge after outpatient spinal or epidural anesthesia with short-duration drugs for low-risk procedures is not necessary, and may result in prolonged discharge times.     

Management of bladder function after outpatient surgery.

BACKGROUND: This study was designed to test a treatment algorithm for management of bladder function after outpatient general or local anesthesia. METHODS: Three hundred twenty-four outpatients, stratified into risk categories for urinary retention, were studied. Patients in category 1 were low-risk patients (n = 227) having non-pelvic surgery and randomly assigned to receive 10 ml/kg or 2 ml/kg of intravenous fluid intraoperatively. They were discharged when otherwise ready, without being required to void. Patients in category 2 (n = 40), also presumed to be low risk, had gynecologic surgery. High-risk patients included 31 patients having hernia or anal surgery (category 3), and 31 patients with a history of retention (category 4). Bladder volumes were monitored by ultrasound in those in categories 2-4, and patients were required to void (or be catheterized) before discharge. The incidence of retention and urinary tract symptoms after surgery were determined for all categories. RESULT: Urinary retention affected 0.5% of category 1 patients and none of category 2 patients. Median time to void after discharge was 75 min (interquartile range 120) in category 1 patients (n = 27) discharged without voiding. Fluids administered did not alter incidence of retention or time to void. Retention occurred in 5% of high-risk patients before discharge and recurred in 25% after discharge. CONCLUSION: In reliable patients at low risk for retention, voiding before discharge appears unnecessary. In high-risk patients, continued observation until the bladder is emptied is indicated to avoid prolonged overdistention of the bladder.     

Voiding in patients managed with or without ultrasound monitoring of bladder volume after outpatient surgery.

The goal of this study was to determine whether recovery room monitoring of bladder volume would affect patient outcome after ambulatory surgery. Incidence of urinary retention and times to void and to discharge were compared in 161 patients managed with ultrasound bladder monitoring versus 173 controls without bladder monitoring. Urinary retention was diagnosed by clinical means or by ultrasound, confirmed by bladder catheterization. Patients were required to void or were catheterized before discharge. In the control patients without underlying risk factors for retention, median time to void was 95 min, and retention occurred in 0.8%, which was not significantly different from the ultrasound group (80 min and 0%, respectively). After hernia/anal surgery or spinal/epidural anesthesia, voiding was delayed (130 and 213 min), incidence of retention was increased (17% and 13%), and there was a trend toward earlier voiding (168+/-99 vs. 138+/-68 min) with bladder monitoring. We conclude that most patients at low risk of retention void within 3 h of outpatient surgery; their outcome is unaffected by bladder monitoring. After hernia/anal surgery and spinal/ epidural anesthesia, the likelihood of urinary retention is increased, and ultrasound monitoring facilitates deciding whether such patients should be catheterized. IMPLICATIONS: Incidence of bladder catheterization and urinary retention were compared in patients managed with and without ultrasound monitoring of bladder volume after outpatient surgery. Monitoring did not alter outcome in patients at low risk of retention, but it facilitated determining when to catheterize patients at high risk of retention (hernia/anal surgery, spinal/epidural anesthesia).     

Management of bladder volumes when using neuraxial anesthesia

The major principles of management of bladder function during outpatient neuraxial blockade include choice of short-acting local anesthetics, avoidance of adding epinephrine, and reasonable fluid administration (750 to 1000 mL) to avoid overdistention of the bladder. Data suggest that low-risk patients are at no greater risk of retention than after general anesthesia, and may be discharged home with similar instructions regarding return if unable to void. High-risk patients may require closer monitoring with a BUS, and catheter drainage if volumes exceed 600 mL.     

Management of Bladder Function after Outpatient Surgery

Background: This study was designed to test a treatment algorithm for management of bladder function after outpatient general or local anesthesia.

Methods: Three hundred twenty-four outpatients, stratified into risk categories for urinary retention, were studied. Patients in category 1 were low-risk patients (n = 227) having non-pelvic surgery and randomly assigned to receive 10 ml/kg or 2 ml/kg of intravenous fluid intraoperatively. They were discharged when otherwise ready, without being required to void. Patients in category 2 (n = 40), also presumed to be low risk, had gynecologic surgery. High-risk patients included 31 patients having hernia or anal surgery (category 3), and 31 patients with a history of retention (category 4). Bladder volumes were monitored by ultrasound in those in categories 2-4, and patients were required to void (or be catheterized) before discharge. The incidence of retention and urinary tract symptoms after surgery were determined for all categories.

Results: Urinary retention affected 0.5% of category 1 patients and none of category 2 patients. Median time to void after discharge was 75 min (interquartile range 120) in category 1 patients (n = 27) discharged without voiding. Fluids administered did not alter incidence of retention or time to void. Retention occurred in 5% of high-risk patients before discharge and recurred in 25% after discharge.     

An evaluation of general and spinal anesthesia techniques for prostate brachytherapy in a day surgery setting

We evaluated four anesthetic techniques for transperineal brachytherapy of the prostate in a day-surgery setting: general anesthesia with either fentanyl and propofol total IV anesthesia (TIVA) or with fentanyl, thiopental, and isoflurane (F-P-I), versus spinal block using 5 mg of 0.5% large-dose spinal hyperbaric bupivacaine (LDS) or 2.5 mg of 0.5% hyperbaric bupivacaine plus fentanyl 25 mug small-dose spinal (SDS). Operating room time was shorter in the general anesthesia groups. TIVA patients voided earlier (103 +/- 41 min) than F-P-I patients (131 +/- 65 min), SDS (126 +/- 55 min), and LDS patients (169 +/- 65 min; P < 0.05 TIVA versus all groups and between spinal groups). TIVA patients were discharged earlier (119 +/- 42 min) than F-P-I patients (160 +/- 69 min) and SDS or LDS patients (132 +/- 53 and 186 +/- 72 min, respectively; P < 0.05 versus all groups and between the spinal groups). There were no intergroup differences regarding postanesthesia nausea or vomiting, pain score, return to normal function at home, or overall satisfaction. Whereas all four techniques are suitable for this procedure, TIVA provides the earliest voiding and consequently fastest discharge. Between spinal techniques, the SDS technique requires more intraoperative sedation but provides earlier voiding and consequently earlier discharge. TIVA, general anesthesia with isoflurane and fentanyl, and two spinal techniques (5 mg of bupivacaine 0.5% or 2.5 mg of bupivacaine 0.5% plus 25 mug of fentanyl) are suitable techniques for transperineal brachytherapy in the day-surgery setting. TIVA allows for earliest voiding and therefore fastest discharge home. Spinal block with 2.5 mg of bupivacaine plus 25 mug of fentanyl provides earlier voiding and consequently earlier discharge than 5 mg of bupivacaine alone.     

Treatment of interstitial cystitis with hydrodistention and bladder training

This study aimed to evaluate the efficacy of hydrodistention (HD) and bladder training for interstitial cystitis (IC). From 1997 to 2006, 361 consecutive IC patients were treated by HD, followed by bladder training. Each patient was followed up using a diary for 8 weeks after HD weekly and monthly thereafter. The efficacy of the treatment was evaluated using the average of the voided volumes and the voiding frequency. The mean +/- standard deviation of the pre-HD daytime voided volumes and voiding frequency were 110.0 +/- 47.0 ml and 14.7 +/- 11.0, respectively. Furthermore, the nocturnal values were 173.1 +/- 91.8 ml and 2.8 +/- 1.7, respectively. After 72 weeks post-HD, the 185 patients who completed the follow-up had volumes/frequency of daytime, 306.5 +/- 80 ml and 6.9 +/- 2.1, respectively, and nocturnal, 325.8 +/- 122.4 ml and 1.3 +/- 0.6, respectively. The implementation of HD and bladder training is crucially important for long-term remission among IC patients.     

Voiding patterns in patients with post-prostatectomy incontinence: urodynamic and demographic analysis

PURPOSE: A significant percentage of patients with post-prostatectomy incontinence have been reported to void by Valsalva's maneuver, which is our observation as well. We determine the mechanism of voiding in patients with post-prostatectomy incontinence and correlate this to demographic data, urodynamic parameters and outcome after artificial urinary sphincter implantation, and identify possible risk factors. MATERIALS AND METHODS: Videourodynamic data from 61 consecutive patients with post-prostatectomy incontinence were reviewed to determine voiding patterns. The causes of incontinence were radical prostatectomy in 58 patients and transurethral resection of the prostate followed by radiation therapy in 3. The relationship between voiding patterns and demographic data (age, diabetes mellitus, degree and duration of incontinence, history of radiation therapy or treated bladder neck contracture) as well as urodynamic parameters (bladder capacity, compliance, instability, sensation, leak point pressure and residual urine) were studied. After artificial urinary sphincter implantation outcome was assessed in relation to the voiding patterns. RESULTS: Stress incontinence was present in all patients while concomitant urgency/urge incontinence was present in 48%. Of the patients 43 (70.5%) voided by detrusor contraction (group 1) while the remaining 18 (29.5%) voided by straining (group 2). Mean patient age +/- SD was 70.8 +/- 6.9 and 69.2 +/- 7.2 years, and duration of incontinence was 48 +/- 33 and 46 +/- 30 months in groups 1 and 2, respectively (p >0.05). Also, no significant differences were found between the groups with regard to other demographic data. Delayed first sensation (at volume greater than 140 ml.) was seen in 42.5% and 29.4%, capacity less than 300 ml. in 41.9% and 39%, impaired/poor compliance in 25.6% and 22.2%, bladder instability in 16.3% and 5.6%, abdominal leak point pressure 60 cm. H(2)O or less in 59.4% and 60% and residual urine greater than 50 ml. in 11.6% and 17.6% in groups 1 and 2, respectively (p >0.05). After artificial urinary sphincter implantation 35% and 22.2% of patients used greater than 1 pad a day in groups 1 and 2, respectively. One patient in each group reported difficulty during urination and both patients had no residual urine. CONCLUSIONS: No identifiable demographic or urodynamic risk factors could be detected in association with the strain pattern of voiding in patients with post-prostatectomy incontinence. The absence of a difference in bladder compliance, residual urine volume and outcome after artificial urinary sphincter implantation between detrusor and strain voiders would suggest no increased risk for complications in the strain voiding group.     

Recovery of Storage and Emptying Functions of the Urinary Bladder after Spinal Anesthesia with Lidocaine and with Bupivacaine in Men

Background: The aim of this study was to evaluate and compare the effects of spinal anesthesia with lidocaine and with bupivacaine on urinary bladder function in healthy men who were scheduled for minor orthopaedic surgical procedures.

Methods: Twenty men were randomly allocated to receive either bupivacaine or lidocaine. Before spinal anesthesia, filling cystometry was performed with the patient in the supine position and a pressure flow study was done with the patient in the standing position. After operation, cystometric measurements were continued until the patient could void urine spontaneously. The levels of analgesia and of motor blockade were recorded.

Results: The urge to void disappeared immediately after injection of the local anesthetics. There was no difference in the duration of lower extremity motor blockade between bupivacaine and lidocaine. Detrusor blockade lasted significantly longer in the bupivacaine group (means +/- SD, 460 +/- 60 min) than in the lidocaine group (235 +/- 30 min). Total fluid intake and urine volume accumulated during the detrusor blockade were significantly higher in the bupivacaine group than in the lidocaine group. In the bupivacaine group, the total volume of accumulated urine (875 +/-385 ml) was also significantly higher than cystometric bladder capacity (505 +/- 120 ml) with the risk of over distension of the bladder. Spontaneous voiding of urine did not occur until segmental sensory analgesia had regressed to the third sacral segment.     

Herpes zoster-associated acute urinary retention: a case report

An 87-year-old woman presents with a 4-week history of urinary incontinence during which she had been treated for disseminated herpes zoster virus (HZV). On physical exam painful vesicles involving the entire vulvar region with mainly right sacral distribution were found. A catheterized volume exceeded 600 ml of retained urine after the patient failed to void spontaneously. Multichannel voiding-pressure urodynamic studies revealed an acontractile neurogenic bladder with overflow incontinence. The patient was discharged on a conservative regimen with arrangement for visiting nurse services to perform intermittent self-catheterization twice daily. Urodynamic testing was repeated 10 weeks after initial symptoms. During voiding cystometry a biphasic increase in detrusor pressure of 15 cm H₂O was observed with no increase in abdominal pressure. The patient emptied 400 ml with a postvoid residual of 300 ml. Recovery from HZV-associated bladder emptying dysfunction can be achieved usually through conservative management, including intermittent self-catheterization. Complete recovery time ranges from 4 to 10 weeks.     

Micturition and uroflowmetric analysis of adult females

Voiding parameters on the Uroflow Diagnostic Interpretation (UDI) were analysed in relation to the voided volume in 58 micturitions of 36 healthy adult females. The maximum flow rate (Qmax) and the mean flow rate during central 90% of the voided volume (QM90) increased linearly up to the voided volume of 400 ml. The voiding time (T100) took a value within a certain range independently of the voided volume from 100 to 400 ml and never exceeded 21 seconds in all micturitions. Voiding time for the central 90% of the voided volume (T90), time to Qmax (TQmax) and time from Qmax to 95% of the voided volume (Tdesc) were independent of the volume voided. The maximum rate of increase of flow rate (dQ/dT max) and the estimated bladder wall contraction velocity at 40 ml bladder contents (dL/dT 40) showed a tendency to increase depending on the volume voided. T100 showed a prolongation in 84.0% of 25 micturitions in 20 neurogenic bladder patients and in 66.7% of 27 in 21 chronic cystitis patients, always accompanied by a prolongation of T90. No other parameters were clearly different between healthy women and patients and/or between the two groups of patients. Voiding time is a useful parameter representing female micturition.     

Healthy, middle-aged, history-free, continent women--do they strain to void?

PURPOSE: We evaluated to what extent abdominal straining is used for voiding in an asymptomatic, continent, healthy, middle-aged female population. MATERIALS AND METHODS: A total of 32 women (mean age 49 +/- 6 years old) could be prospectively included. Technical investigations consisted of flowmetry, pressure flowmetry with EMG and electrosensation evaluation. Some data were compared with those of stress incontinent women investigated prospectively in the same way. RESULTS: There were 4 women who were excluded from analysis because of abnormal sensory evaluation. The symptom-free participants voided with low detrusor pressure, a high flow rate and no residual. A large segment (42%) used additional abdominal straining to void on cystometry and reported that such straining was their usual habit for voiding at home. Straining was seen as frequent in women with stress incontinence. However, significantly more women with stress incontinence used straining without detrusor contraction. CONCLUSIONS: These healthy middle-aged women without a history of pelvic surgery, or symptoms or signs of urological, anorectal or gynecological problems, voided with a mean Pdetmax of 25 cm H(2)O, mean Qmax of 29 ml per second, and the majority without residual. Many of them strained during detrusor contraction and this had not led to the development of signs or symptoms. The way straining is done may make the difference in that during reflex bladder contraction and urethral relaxation, additional straining may have little negative effect. If straining is used to void without the initiation of the micturition reflex, voiding dysfunction and incontinence might develop more easily.     

Bladder inhibition or voiding induced by pudendal nerve stimulation in chronic spinal cord injured cats

AIMS: To investigate pudendal-to-bladder spinal reflexes in chronic spinal cord injured (SCI) cats induced by electrical stimulation of the pudendal nerve. METHODS: Bladder inhibition or voiding induced by pudendal nerve stimulation at different frequencies (3 or 20 Hz) was studied in three female, chronic SCI cats under alpha-chloralose anesthesia. RESULTS: Voiding induced by a slow infusion (2-4 ml/min) of saline into the bladder was very inefficient (voiding efficiency=7.3%+/-0.9%). Pudendal nerve stimulation at 3 Hz applied during the slow infusion inhibited reflex bladder activity, and significantly increased bladder capacity to 147.2+/-6.1% of its control capacity. When the 3-Hz stimulation was terminated, voiding rapidly occurred and the voiding efficiency was increased to 25.4+/-6.1%, but residual bladder volume was not reduced. Pudendal nerve stimulation at 20 Hz induced large bladder contractions, but failed to induce voiding during the stimulation due to the direct activation of the motor pathway to the external urethral sphincter. However, intermittent pudendal nerve stimulation at 20 Hz induced post-stimulus voiding with 78.3+/-12.1% voiding efficiency. The voiding pressures (39.3+/-6.2 cmH2O) induced by the intermittent pudendal nerve stimulation were higher than the voiding pressures (23.1+/-1.7 cmH2O) induced by bladder distension. The flow rate during post-stimulus voiding induced by the intermittent pudendal nerve stimulation was significantly higher (0.93+/-0.04 ml/sec) than during voiding induced by bladder distension (0.23+/-0.07 ml/sec). CONCLUSIONS: This study indicates that a neural prosthetic device based on pudendal nerve stimulation might be developed to restore micturition function for people with SCI.     

Walking reduces the post-void residual volume in parturients with epidural analgesia for labor: a randomized-controlled study

Background: The post-void residual volume is higher among parturients who received epidural analgesia than those who received no or alternative analgesia.
Methods: This prospective, randomized, controlled, non-blinded study was performed in a tertiary referral center labor suite. The post-void residual volume was measured by a transabdominal ultrasound following a voiding attempt. Healthy parturients with low-dose epidural analgesia in active labor were randomized either to walk to the toilet or to use a bedpan for voiding. The primary outcome measure (post-void residual volume in labor) was compared between the study groups.
Results: The toilet group ( n =34) and the bedpan group ( n =28) demonstrated similar post-void residual volumes (212 ± 100 vs. 168 ± 93 ml, P =0.289). Twenty patients (59%) randomized to the toilet group were unable to walk and actually voided in a bedpan. A secondary analysis was performed analyzing the groups as treated. The post-void residual volume was significantly lower in the actual toilet group ( n =14, 63 ± 24 ml) vs. the bedpan group ( n =48, 229 ± 200 ml), P =0.0052. Thirteen (93%) women who walked to the toilet managed to void before the ultrasound measurement vs. 20/48 (42%) using the bedpan, P =0.001. Fewer women who managed to walk to the toilet required urinary bladder catheterization during the labor than women who used the bedpan (6/14, 43% vs. 36/48, 75%) P =0.028.
Conclusion: Women who were randomized to walk to the bathroom with epidural analgesia and were able to do so during labor had a significantly reduced post-void residual volume and a reduced requirement for urinary catheterization.     

Altered NGF regulation may link a genetic predisposition for hypertension with hyperactive voiding

PURPOSE: Hyperactive voiding and elevated smooth muscle NGF output are traits of the spontaneously hypertensive rat (SHR). Elevated target-derived NGF is associated with hypertension and hyperactive voiding in SHRs. In the present study, we tested for possible genetic links between hypertension, hyperactive voiding and augmented bladder smooth muscle cell (BSMC) NGF secretion. MATERIALS AND METHODS: We crossed SHRs with WKYs to produce a gene segregating F2 population. We measured F2 mean arterial blood pressure (BP) and six-hour voiding frequency. BSMCs were cultured from 'Low BP F2s' (95+/-2) and 'High BP F2s' (141+/-3 mm. Hg) and conditioned medium tested for NGF with a two-site ELISA. The NGF regulators isoproterenol, platelet-derived growth factor (PDGF) and phorbol-12-myristate-13-acetate were tested in F2 BSMC cultures. RESULTS: A positive correlation (r = 0.75) between blood pressure and voiding frequency existed in this F2 population. As BP rose voiding frequency increased and volume per void decreased such that there were no significant changes in total urine voided (Low BP F2s: 1.0+/-0.5; High BP F2s: 6.2+/-0.5 voids/6 hours). Low BP F2s (2.0+/-0.2) secreted NGF at a higher basal rate than High BP F2s (0.7+/-0.1 fg NGF/hr/100 cells). However, High BP F2s (1,620 and 3,850) were oversensitive to isoproterenol and PDGF-induced increases in NGF output, compared with Low BP F2s (219 and 1,282% control, respectively). CONCLUSIONS: Elevated tissue NGF due to a hypersensitivity to NGF regulating stimuli, rather than alterations in basal NGF, may genetically link hypertension and hyperactive voiding.     

Effect of lumbar-epidural administration of tramadol on lower urinary tract function

AIMS: Intrathecal and epidural administration of micro-agonist opioids is associated with urinary retention, a potentially serious adverse-event. In animal studies tramadol has been found not to affect voiding function. We evaluated urodynamic effects of epidural tramadol in humans. METHODS: Fifteen adults planned for cystoscopy under local-anesthesia underwent urodynamics (UDS) at baseline and 30 min after administration of 100 mg tramadol in lumbar-epidural space. UDS consisted of filling cystometry, pressure-flow study and pelvic floor electromyography (EMG). Subsequently, all underwent cystoscopy and were observed for 6 hr. RESULTS: After injection of tramadol, a significant rise was observed in bladder capacity (391.8 +/- 179.6 ml vs. 432.7 +/- 208.8 ml; P = 0.019) and compliance (60.1 +/- 51.5 ml/cm H(2)O vs. 83.0 +/- 63.0 ml/cm H(2)O; P = 0.011) without a significant change in filling pressure (22.5 +/- 13.2 cm H(2)O vs. 24.1 +/- 15.1 cm H(2)O; P = 0.576). Filling sensations were delayed significantly (P < or = 0.05). EMG during filling phase showed a significant fall (P = 0.027). Peak flow-rate (Q(max)), average flow-rate, postvoid residue and detrusor pressure-at-Q(max) did not show significant change from baseline (P > 0.05). Three patients had bladder outlet obstruction which did not worsen after the injection. Guarding reflex was inhibited in seven out of 12 patients who had it at baseline (P = 0.016). CONCLUSIONS: Epidural tramadol increases the bladder capacity and compliance and delays filling-sensations, without ill effect on voiding. This seems true even for patients with obstructed outflow; however, due to small number of patients a definite conclusion cannot be derived. These results will guide clinician to avoid catheterization in cases where epidural tramadol is used for postoperative pain. The inhibitory effects of tramadol on EMG activity are intriguing and need further studies.     

Filling and voiding pressures measured by ambulatory monitoring and conventional studies during natural and artificial bladder filling

A total of 20 men awaiting elective prostatectomy for bladder outflow obstruction underwent conventional medium filling cystometry and ambulatory monitoring of bladder pressures during natural bladder filling. Total bladder capacity was similar during both tests (medium filling cystometry 256 +/- 138 ml. and ambulatory monitoring 248 +/- 120 ml., p not significant) as was the voided volume (medium filling cystometry 180 +/- 100 ml. and ambulatory monitoring 179 +/- 88 ml., p not significant). However, the peak urinary flow rate at the end of medium filling cystometry (4 +/- 6 ml. per second) was significantly lower than during ambulatory monitoring (9 +/- 4 ml. per second, p less than 0.05). The bladder contraction pressure during medium filling cystometry (79 +/- 44 cm. water) was significantly lower than during ambulatory monitoring (107 +/- 39 cm. water, p less than 0.005). Bladder pressures during voiding recorded after natural filling were significantly greater than after artificial filling. This finding may have significant implications for the use of conventional cystometry to study conditions such as outflow obstruction.     

Variation in urinary flow according to voiding position in normal males.

Our objective was to study whether the urinary flow rate would vary according to voiding position. Twenty-one normal healthy male volunteers aged 24 to 40 years (mean, 29 years) were studied. The bed used was designed so that a hole could be opened at its center for voiding, and the bed could be bent at two points so that the subject could void in various positions. Urinary flow was measured with a portable uroflowmeter (P-Flow), which permits measuring urinary flow rate. Each subject assumed five voiding positions (standing, sitting, lateral, supine, and prone) in random order. Urinary flow was measured at least twice in each position to record a stable voiding. For voiding in the lateral position, subjects were instructed to void while bending the upper leg to keep an open angle between the legs. All subjects were also instructed to void without increasing abdominal pressure. Maximum flow rate was 20.7 +/- 6.59 mL/sec with voided volume of 262 +/- 77.8 mL in the lateral, 22.1 +/- 7.05 mLl/sec with voided volume of 309 +/- 130 mL in the supine, 25.0 +/- 8.25 mL/sec with voided volume of 287 +/- 122 mL in sitting, 27.1 +/- 8.89 mL/sec with voided volume of 263 +/- 102 mL in the standing, and 28.7 +/- 10.6 mL/sec with voided volume of 303 +/- 98 mL (mean +/- SD) in the prone positions. The maximum and mean urinary flow rates were greatest in the prone position. With regard to these parameters, significant differences were noted between the prone and lateral positions and between the prone and supine positions. In conclusions, the maximum urinary flow rate was highest in the prone position, followed by the standing, sitting, supine, and finally the lateral positions in normal males. Neurourol. Urodynam. 18:553-557, 1999.     

Voiding after gynecologic surgery: Experience with 24-hour Foley catheterization

Postoperative voiding was studied in 227 gynecologic patients after the introduction of a new routine of 24-hour Foley catheterization in all patients. After catheter removal 85% of patients (laparotomy 88.2%, colposuspension 85.2% and vaginal plastic surgery 80.3%) were able to void spontaneously, with residual urine <100 ml. 13.7% of patients had intermittent catheterization 1–3 times (mean 1.6) but established satisfactory voiding before evening. Altogether 98.7% of patients (laparotomy 99%, colposuspension 98.1%, vaginal surgery 98.6%) voided adequately before the end of the first postoperative day. One patient in each group had prolonged retention and required 3–63 days before voiding normally. The differences in retention rates between the three surgical groups were not statistically significant. The regimen of 24-hour postoperative Foley catheterization followed by intermittent catheterization if required is convenient and may be recommended after all common gynecologic operations.