Position-related changes in uroflowmetric parameters in healthy young men

AIMS: Uroflowmetric measurements are a common procedure in urological examination of patients presenting with lower urinary tract symptoms and it can be influenced by various factors. In this study, we investigated position-related changes in uroflowmetric parameters and postvoiding residual urine (PVR) volume in healthy young men. MATERIALS AND METHODS: Thirty normal healthy male volunteers, whose mean age was 28.6 +/- 0.7 years old were studied and evaluated with uroflowmetry in the standing, sitting, and squatting down voiding positions. Three measurements were obtained for each voiding position and for each man (total 270 urinary flows). PVR were measured by transabdominal ultrasound. The maximum flow rate (Q(max)), average flow rate (Q(ave)), corrected maximum flow rate (cQ(max)), voiding volume (VV), voiding time (VT), and PVR values were compared between the three different voiding positions. RESULTS: The mean Q(max) values for the standing, sitting, and squatting down voiding positions of the patient group were 26.8 +/- 1.3, 31.3 +/- 1.2, 31.0 +/- 1.0 ml/sec, respectively and the mean Q(ave) values were 16.8 +/- 0.6, 18.5 +/- 0.6, 18.6 +/- 0.6 ml/sec, respectively. There were significant differences between voiding positions regarding the Q(max) (P < 0.0001) and Q(ave) (P = 0.0002) values in the patient groups. However, the difference between VT, VV, and PVR in the standing, sitting, and squatting down voiding position of the patient group was not statistically significant. CONCLUSIONS: Our results suggest that the urinary flow rates are affected by the voiding position. Therefore, it is important to perform uroflowmetric measurements in the same position.     

Voiding position does not affect uroflowmetric parameters and post-void residual urine volume in healthy volunteers

OBJECTIVE: To investigate the effect of voiding position using uroflowmetry and post-void residual (PVR) urine volume assessment in healthy men and women. MATERIAL AND METHODS: The study population comprised 72 healthy volunteers. The mean (range) ages of the male (n = 36) and female (n = 36) subjects were 30 (18-40) years and 32 (21-44) years, respectively. The uroflowmetric studies were repeated in the standing, sitting and crouching positions for men and in the sitting and crouching positions for women. At least three measurements were obtained for all voiding positions for each volunteer. PVR volumes were measured using trans-abdominal ultrasound after each voiding. Maximum flow rate (Qmax), average flow rate (Qave), voided volume (VV) and PVR values obtained in each voiding position were compared with those obtained in the other positions. Comparisons were done using one-way ANOVA. RESULTS: The mean Qmax and Qave values obtained in the sitting, crouching and standing positions in men were 24.29 +/- 0.73 and 15.67 +/- 0.37, 23.28 +/- 0.64 and 15.56 +/- 0.33, and 23.58 +/- 0.63 and 15.81 +/- 0.34 ml/s, respectively. The mean VV and PVR values obtained in the sitting, crouching and standing positions in men were 297.5 +/- 12.71 and 13.52 +/- 1.02, 306.3 +/- 13.46 and 14.02 +/- 1.08, and 309.9 +/- 13.14 and 12.92 +/- 0.95 ml, respectively. In women, the mean Qmax and Qave values obtained in the sitting and crouching positions were 28.09 +/- 0.66 and 18.26 +/- 0.36, and 27.98 +/- 0.59 and 17.31 +/- 0.35 ml/s, respectively. The mean VV and PVR values obtained in the sitting and crouching positions in women were 331.8 +/- 13.28 and 11.82 +/- 0.99, and 326.9 +/- 12.87 and 12.79 +/- 1.07 ml, respectively. There were no significant differences in any of the parameters between voiding positions in either group. CONCLUSION: Urinary flow rates and PVR urine volume do not seem to be affected by voiding position in healthy men and women.     

Effect of voiding position on uroflowmetric parameters and post-void residual urine volume in patients with benign prostatic hyperplasia

OBJECTIVE: To investigate the effect of position on voiding using uroflowmetry and post-void residual (PVR) urine volume assessment in patients with lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). MATERIAL AND METHODS: A total of 44 patients (mean age 61.7 years; range 47-72 years) with symptomatic BPH and 44 healthy men (mean age 60.3 years; range 40-67 years) who were used as controls were enrolled in the study. The uroflowmetric studies were performed in both standing and sitting positions. At least two measurements were obtained for both voiding positions for each participant. The PVR volumes were measured by means of a transabdominal ultrasound probe after each voiding. The maximum flow rate (Qmax), average flow rate (Qave), voided volume (VV) and PVR values were compared between the two different voiding positions. RESULTS: The mean Qmax values for the standing and sitting positions in the patient group were 10.2+/-0.49 and 9.5+/-0.55 ml/s, respectively and the mean Qave values were 4.7+/-0.25 and 4.7+/-0.31 ml/s, respectively. The mean VV values for the standing and sitting positions in the patient group were 292.6+/-17.19 and 271.1+/-15.51 ml, respectively and the mean PVR values were 82.2+/-10.97 and 85.5+/-12.46 ml, respectively. The mean Qmax values for the standing and sitting positions in the control group were 24.8+/-0.78 and 25.3+/-0.78 ml/s, respectively and the mean Qave values were 13.2+/-0.36 and 13.5+/-0.33 ml/s, respectively. The mean VV values for the standing and sitting positions in the control group were 275.9+/-10.79 and 278.0+/-10.23 ml, respectively and the mean PVR values were 11.9+/-1.16 and 10.7+/-1.06 ml, respectively. There were no significant differences between voiding positions regarding the Qmax (p = 0.360), Qave (p = 0.978), VV (p = 0.355) or PVR (p = 0.842) values in the patient group. Similarly, there were no significant differences between voiding positions regarding the Qmax (p = 0.638), Qave (p = 0.537), VV (p = 0.890) or PVR (p = 0.412) values in the control group. CONCLUSION: The urinary flow rates and PVR urine volume do not seem to be affected by the voiding position (standing or sitting) either in patients with BPH or in healthy men.     

Respiratory function and ribcage contribution to ventilation in body positions commonly used during anesthesia

Lung function tests are normally performed in the upright position, whereas anesthesia is usually administered with the patient in the supine position, and occasionally in other postures. We therefore compared forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), functional residual capacity (FRC), and ribcage contribution to ventilation by respiratory inductive plethysmography in 13 conscious healthy male volunteers, sitting and in four horizontal positions used during anesthesia. Forced vital capacity and FEV1 were similar in all positions, except for a significant mean increase in FVC of 300 mL (SD 213) when sitting compared with when supine (P less than 0.001). The mean decrease in FRC was 806 mL (SD 293) between the sitting and supine positions (P less than 0.001). A significant increase in FRC occurred (252 mL, SD 329, P less than 0.01) when supine subjects raised their arms above their heads as required for computed tomography. Functional residual capacity in the prone and lateral positions was significantly larger than in the supine position (mean change 350 mL, P less than 0.001), but was still some 450 mL less than in the sitting position. Mean ribcage contribution was similar in all horizontal positions (32%-36%), whereas supine values were significantly different from those of the sitting position (mean 70%, SD 11, P less than 0.001). In conclusion, the various horizontal postures studied have no effect on FVC, FEV1, or ribcage contribution to ventilation. However, FRC in the prone, lateral, and arms-up positions is on average 250 mL larger than in the supine position, an observation that may affect gas exchange during anesthesia in these positions.     

Detrusor pressure uroflowmetry studies in women: effect of a 7Fr transurethral catheter

PURPOSE: We evaluated whether a 7Fr transurethral catheter affects urinary flow in women undergoing pressure flow studies for voiding symptoms. MATERIALS AND METHODS: We reviewed a urodynamic database of 600 consecutive women referred for the evaluation of voiding symptoms. Before urodynamics all patients voided privately using a standard toilet and free flow was recorded. Urodynamics were performed using a 7Fr double lumen transurethral catheter. At functional bladder capacity patients were asked to void in the sitting position and pressure flow studies were performed. All uroflowmetry tracings were inspected and analyzed manually. Only patients who voided similar volumes varying by less than 20% on the free and pressure flow studies were assessed. Free and pressure flow parameters were compared according to voided volume category, main urodynamic diagnosis, uroflowmetry pattern and pre-void bladder volume. RESULTS: A similar volume was voided on the free and pressure flow studies of 100 women. In each voided volume category and urodynamic diagnosis pressure flow parameters were significantly different from the equivalent free flow parameters in all but 4 cases. Specifically the maximum flow rate was significantly less and flow time was significantly longer on pressure versus free flow studies (each p <0.01). An intermittent flow pattern was more common on pressure than in free flow measurements (43% versus 9%). CONCLUSIONS: A 7Fr transurethral catheter may adversely affect uroflowmetry parameters in women undergoing pressure flow studies for lower urinary tract symptoms. This finding may have further clinical implications regarding the interpretation of these parameters as well as establishment of an accurate diagnosis.     

Data from frequency-volume charts versus filling cystometric estimated capacities and prevalence of instability in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia

The aim was to examine associations of filling cystometric estimated compliance, capacities, and prevalence of bladder instability with data from frequency-volume charts in a well-defined group of men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH). Men with LUTS suggestive of BPH were included if they met the criteria of the International Consensus Committee on BPH, i.e., they voided more than 150 mL during uroflowmetry, their residual volume and prostate size were estimated, and they completed frequency-volume charts correctly. From the frequency-volume charts, voiding habits, and fluid intake in the daytime and at night were evaluated. Filling cystometric studies were performed in these men as well. Decreased compliance was an exceptional finding. Cystometric capacity and especially effective capacity (cystometric capacity minus residual volume) corresponded significantly with the maximum voided volume on the frequency-volume charts. Effective capacity was almost twice as high as the average voided volume. Minimum voided volume on frequency-volume charts was not related to filling cystometric data. The presence of instability in the supine or sitting position or in both positions was not significantly associated with smaller voided volumes, higher nocturia, or diuria. Filling cystometric capacities were strongly associated with maximal and mean voided volumes derived from frequency-volume charts. The presence of detrusor instability during filling cystometry did not significantly affect voided volumes, diuria, or nocturia     

The effect of psychological motivation on volumes voided during uroflowmetry in healthy aged male volunteers

AIMS: To study the effect of psychological motivation on the voided volume during uroflowmetry in aged-male volunteers. METHODS: An open contest of free-flow rate was held for the elderly community. People over 60 years old with no prior history of lower urinary tract symptoms were invited to compete. Participants were given the suggestion to void only when strong desire was experienced because greater the volume, faster the flow. One month later, 20 of the male participants were asked to come back for an office uroflowmetry, given the instruction to hold until strong desire was experienced. The results of the maximum flow rate, mean flow rate, and voided volume were compared between these two tests. RESULTS: In the first uroflowmetry, the average voided volume for the 20 participants was 532+/- 109 ml; maximum flow rate and average flow rate were 27.1+/- 9.4, and 17.2+/- 6.4 ml/sec, respectively. The voided volume decreased significantly in the second uroflowmetry (338+/- 82 ml, P<0.01); the maximum and average flow rates did not changed significantly (24.2+/- 9.5 and 14.9+/- 6.9 ml/sec, respectively). No participant had a shift of more than one standard deviation between the two tests on the Siroky's flow-rate nomogram. CONCLUSIONS: With psychological motivation to win the contest, the participants showed greater tolerance to bladder filling. This suggests that the state of mind can affect the perception on bladder sensation. On the other, the performance on emptying function is not significantly improved by motivation.     

Measurements of pelvic flexion angle using three-dimensional computed tomography

The purpose of the current study was to evaluate whether safe acetabular component position depends on differences in pelvic location between the supine, standing, and sitting positions. The subjects of the current study were 101 patients who had total hip arthroplasty. Anteroposterior radiographs of the pelvis with the patients in the supine, standing, and sitting positions were obtained preoperatively and 1 year after total hip arthroplasty. Computed tomography images of the pelvis were obtained preoperatively. Using image matching between the three-dimensional computed tomography model and anteroposterior radiograph, pelvic flexion angles with the patient in the supine, standing, and sitting positions were calculated. The mean preoperative pelvic flexion angle was 5 degrees +/- 9 degrees (range, -37 degrees -30 degrees ) in the supine position, 3 degrees +/- 12 degrees (range, -46 degrees -33 degrees ) in the standing position, and -29 degrees +/- 12 degrees (range, -62 degrees -10 degrees ) in the sitting position. Because there was much intersubject variability in pelvic flexion angle, it is not appropriate to determine orientation of the acetabular component from anatomic landmarks. In 90% of the cases, the difference in pelvic flexion angle between the supine and standing positions preoperatively was 10 degrees or less. In 90% of the cases, there was 20 degrees or greater extension of the pelvis from the supine position to the sitting position preoperatively, and the safe range of flexion of the hip from anterior prosthetic impingement in the sitting position was 20 degrees or greater than that in the supine position. Preoperative pelvic position in each case was almost completely maintained 1 year after total hip arthroplasty. It is reasonable to regard the pelvic position in the supine position as the functional pelvic position and proper pelvic reference frame in determining optimal orientation of the acetabular component in 90% of cases before and 1 year after total hip arthroplasty, although an adjustment of orientation of the acetabular component was needed for the remaining cases.     

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.     

Measurement of urinary flow rate using ultrasound in young boys and infants

PURPOSE: We present a technique for measuring urinary flow rates with ultrasound in male infants and children. MATERIALS AND METHODS: Urinary flow rate was measured simultaneously by an ultrasound probe placed around the base of the penis and by a funnel with a rotating disk at the bottom in 30 boys with a mean age of 6.7 years (range 4.5 to 10.5), and by ultrasound in 8 infants with a mean age of 10 months (range 1 to 28). Voided volume was measured with a graded cylinder or calculated from the weight change of diapers in infants. Ultrasound and rotating disk maximum flow rates were calculated. The ultrasound signal was calibrated by comparing the collected voided volume to the area under the curve for that void. The volume calculated from the rotating disk flow rate curve was also compared with the collected volume. RESULTS: Both methods yielded similar flow curves. However, ultrasound maximum flow rate significantly exceeded rotating disk maximum flow rate (13 +/- 6 ml. per second, range 5 to 22 versus 10 +/- 4 ml. per second, range 4 to 21, t test p <0.001). The underestimation of the flow rate by the rotating disk method may have been due to adherence of urine to the funnel wall. Rotating disk maximum flow rate was lower and voided volume was underestimated by up to 50% (average 15 +/- 2%) in 21 cases. Ultrasound maximum flow rate averaged 6 +/- 3 ml. per second (range 3 to 11.6 [oldest infant]) in the 8 infants. CONCLUSIONS: Urinary flow rates can be measured accurately using ultrasound in boys who produce small volumes and/or who are not toilet trained and also in infants. In future studies ultrasound will be applied to subsets of male infants with bladder dysfunction.     

Preoperative urodynamic evaluation may predict voiding dysfunction in women undergoing pubovaginal sling

PURPOSE: We determine which urodynamic parameters can best predict postoperative voiding dysfunction following pubovaginal sling surgery. MATERIALS AND METHODS: The records of 98 consecutive women who had undergone pubovaginal sling surgery with allograft fascia lata between July 1998 and July 2000 were reviewed. Urodynamic and followup data were sufficient for evaluation for 73 patients. Urodynamic and clinical parameters were correlated with urinary retention, time to return of efficient voiding and development of postoperative urgency symptoms. RESULTS: Average time to return of efficient voiding was 3.92 days (median 3). Of 21 women who voided without a detrusor contraction urinary retention developed in 4 (23%) versus 0 of 48 who voided with detrusor contraction (p = 0.007). Urinary retention was defined as the need to perform even occasional self-catheterization. All 4 women with urinary retention had a detrusor pressure of less than 12 cm. H(2)O (0 in 3, 4 in 1). None of the women with a detrusor pressure of greater than 12 cm. H(2)O had urinary retention (p = 0.047). The presence of Valsalva voiding in women without a detrusor contraction did not affect the incidence of urinary retention (11.1%) compared to those who did not demonstrate Valsalva voiding (5.1%) (p = 0.603). Peak flow rate, detrusor instability on preoperative urodynamics and post-void residual urine volume were not associated with postoperative urinary retention. Finally, post-void residual urine volume predicted delayed return to normal voiding (p = 0.001). There were no other urodynamic parameters that were significantly associated with urinary retention, delayed return to normal voiding or postoperative urgency symptoms including peak flow rate, capacity or compliance. CONCLUSIONS: Women who void without or with a weak detrusor contraction are most likely to have urinary retention postoperatively. Therefore, we conclude that preoperative urodynamic evaluation may be used to counsel women regarding the risk of urinary retention following the pubovaginal sling procedure.     

Uroflowmetry nomogram in Iranian children aged 7 to 14 years

Background

As the voiding habits of Iranian children differs from other children because of some cultural and religious considerations, we aimed to establish normal reference values of urinary flow rates in Iranian children between 7 to 14 years of age.

Methods

Eight hundred and two uroflowmetry studies were performed on children with no history of a renal, urological, psychological or neurological disorder, between the ages 7 and 14. Five hundred twenty five studies from 192 girls and 335 boys were considered in this study excluding the staccato/interrupted voiding pattern or voided volume less than 20 ml. The voiding volume, the maximum and average urinary flow rates were extensively analyzed.

Results

The maximal and average urine flow rate nomograms were plotted for both girls and boys. Mean maximum urine flow rate was 19.9 (ml/sec) for boys and 23.5 (ml/sec) for girls with a mean voided volume of 142 (ml) for boys and 147 (ml) for girls. Flow rates showed a close association with voiding volume in both sexes. The maximum and average flow rates were higher in girls than in boys, and they showed a significant increase in flow rates with increasing age, where boys did not. The mean maximum urine flow rates (19.9 ml/sec for boys and 23.5 ml/sec for girls) were found to be higher in this study than other studies.

Conclusion

Nomograms of maximal and average flow rates of girls and boys are presented in centile form, which can help the physician to evaluate the response to medical or surgical treatment and be useful for the screening of lower urinary tract disturbances in children, for a wide range of voided volumes.     

Normal variation and influence of stress,caffeine intake,and sexual activity on uroflowmetry parameters of a middle-aged asymptomatic cohort of volunteer male urologists

AIMS: To assess normal variations of uroflowmetry in middle-aged asymptomatic male urologists and to analyse the influence of stress, caffeine intake, and sexual activity. METHODS: Thirty-one male urologists from Quebec and Ontario were recruited for this study. All were healthy, not taking any current medications known to interfere with lower urinary tract function, and symptom-free (International Prostate Symptom Score less than 5). Each received two identical flowmeters to keep over a period of 2 weeks, one at home and one in his busiest office. Ten uroflow tracings, with a volume greater than 150 mL, were requested from each of them; five at home and five in the office. A total of 310 flows were analysed. The subjective level of stress, coffee intake, and sexual activity, in the hour before each uroflowmetrogram, was recorded, through a short self-administered questionnaire and stress visual scale. RESULTS: are presented as an average per individual. The voided volume was 331.9 mL, with an SD of 94.8 mL. The voiding time was 32.7 seconds (SD=15.5). The peak flow rate was 20.5 mL/sec (SD=3.9), the mean flow rate was 14.3 mL/sec (SD=3.0), and the time to maximum flow was 7.2 sec (SD=4.0). Subjective levels of stress did not significantly change these parameters. Uroflows were obtained with and without coffee drinking. The voided volume was 337.4 mL (SD=109.2) vs. 290.8 mL (SD=77.3) (P=0.03), and peak flow rate 19.4 mL/sec (SD=4.1) vs. 18.9 mL/sec (SD=3.1) (P=0.49), respectively. CONCLUSIONS: Uroflowmetry parameters and voided volume are highly variable in a normal asymptomatic population. Subjective stress level does not seem to have an influence on these parameters. Coffee intake significantly increases the voided volume but does not change the peak flow rate. These conclusions should be considered when using uroflowmetry parameters as an outcome measure.     

Radionuclide assessment of bladder-emptying function in normal male population and in patients before and after prostatectomy.

Radionuclide assessment of the bladder-emptying function was evaluated in 82 normal individuals and in 16 patients before and after prostatectomy. The parameters evaluated were: average flow rate (AFR), peak flow rate (PFR), corrected peak flow rate (CPFR = PFR/[bladder volume] 0.5), ejection fraction (EF) of the bladder, and post-voiding residual urine (RU) volume. A good interobserver reproducibility was found in 19 measurements. Urinary flow rates, EF, and RU showed a highly significant statistical difference between normal individuals and patients before surgery: AFR, 9.2 +/- 5.1 vs. 2.9 +/- 1.5 mL/sec; PFR, 19.5 +/- 9.2 vs 7.4 +/- 3.2 mL/sec; CPFR, 1.17 +/- 0.34 vs 0.54 +/- 0.22; EF, 95.6 +/- 4.6 vs 68.2 +/- 23.2 percent; and RU, 11.8 +/- 15.8 vs 93.4 +/- 115 mL; respectively. After prostatectomy the urinary flow rates showed a highly significant improvement and did not differ from the normal individuals: AFR, 7.9 +/- 2.7 mL/sec; PFR, 19.0 +/- 6.4 mL/sec; and CPFR, 1.32 +/- 0.57. The EF after surgery (91.7 +/- 10.9%) was lower than in normal individuals, but showed a significant improvement compared with EF before surgery. The RU after surgery (27.4 +/- 48.0 mL) although lower than before surgery did not differ significantly and was greater than in the normal individuals. No relationship between age and flow was found in this study. Both average and peak flow rates were related to the bladder volume. This method involves a single, noninvasive procedure which enables determination of bladder-emptying function.     

Loads on internal spinal fixators measured in different body positions

Telemeterized internal spinal fixation devices were implanted in ten patients. The loads acting on the fixators were compared for different body positions, including standing, sitting, and lying in a supine, prone, and lateral position. Implant loads differed considerably from patient to patient depending, for example, on the indication for surgery and the surgical procedure. They were altered by anterior interbody fusion. Mostly, only small differences in implant loads were found for the various lying positions. Flexion bending moments were significantly higher in upright than in lying body positions. Loads on the fixators were not higher for sitting than for standing. Patients who have undergone mono- or bisegmental spine stabilization should therefore be allowed to sit as soon as they can leave the bed. Received: 16 July 1999 Accepted: 20 July 1999     

Effects of diabetes on female voiding behavior

PURPOSE: We studied voiding behavior in women with type 2 diabetes vs nondiabetic female controls and examined factors associated with voiding dysfunction in patients with diabetes. MATERIALS AND METHODS: After eliminating coexisting medical factors that could affect voiding function we evaluated voiding behaviors in 194 female patients with diabetes treated regularly at a diabetic clinic and 162 control women using a lower urinary tract symptom questionnaire based mainly on the American Urological Association Symptom Index questionnaire and free flow analyses with post-void residual urine estimates. Emptying efficiency was defined as 100% x volume voided/(volume voided + post-void residual urine). RESULTS: Compared with controls patients with diabetes had significantly higher nocturia scores (p = 0.003), weaker urinary streams (p = 0.02), less voided volumes (220 +/- 97 vs 280 +/- 104 ml, p = 0.04) and lower maximal flow rates (19.4 +/- 8.4 vs 25.9 +/- 8.5 ml per second, p <0.001). Remarkable residual urine (100 ml or greater) was detected in 1.8% of controls vs 13.9% of patients. After controlling for age and voided volume diabetes was significantly associated with a decrease in baseline maximum flow of 4.5 ml per second (95% CI 2.9 to 6.2). In patients with diabetes peripheral neuropathy was an independent factor associated with the decrease in emptying efficiency (p = 0.03). CONCLUSIONS: Diabetes significantly altered voiding patterns in a significant proportion of women treated at the diabetic clinic. Peripheral neuropathy is an important factor associated with diabetic voiding dysfunction.     

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.     

Voiding function study with ultrasound in male and female neonates

BACKGROUND: The neonatal period has been characterized as a time when males have a much higher incidence of urinary infection and severe ureteral reflux than females. However, little information about the voiding function in the neonatal period is available. METHODS: The bladder urine volumes, before and after voiding, and urinary flow rates were determined with the use of noninvasive voiding-provocation maneuvers and ultrasound in the apparently normal neonates. RESULTS: There was no significant difference in the prevoid bladder urine volume between the two sexes. After they were stimulated to enhance the tension of their abdominal wall musculature, 65 of 118 females (55.1%) and 64 of 115 males (55.7%) voided. The voiding was observed in 94 (81.0%) of the 116 neonates who had had a prevoid volume above 12 ml. The residual urine expressed as a percentage of the prevoid volume was significantly higher in the males (median, 12.0% in males vs. 3.0% in females, P < 0.01), with the values being above 20% in 26 (41%) of the 64 males compared with 10 (15%) of the 65 females (P < 0.01). Urinary flow rates, determined in 52 neonates, were significantly smaller in males than in females (mean +/- SD, 2.6 +/- 0.9 g/second vs. 3.8 +/- 1.3 g/second, respectively, P < 0.001). CONCLUSION: This voiding function study with ultrasound using noninvasive voiding-provocation maneuvers successfully revealed that male neonates have a larger residual urine volume and smaller urinary flow rates than female neonates. This study should be useful for the diagnosis of voiding dysfunction in children with abnormal urinary symptoms.     

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.     

Maximum and average urine flow rates in normal male and female populations--the Liverpool nomograms

The study of voiding in men and women has been handicapped by the lack of a normal reference range covering urinary flow rates over a wide range of voided volumes. Normal volunteers (331 males and 249 females) were studied. Each voided once into a calibrated Dantec Urodyn 1000 mictiograph. On a second occasion 282 men and 46 women voided. The maximum and average urine flow rates of the first voids in both sexes were compared with the respective voided volumes. Nomogram charts, in centile form, for both the maximum and average urine flow rates were constructed using statistical transformations of the data. Males showed a significant decline in both urinary flow rates with age, although there was no statistically significant variation in either urine flow rate with respect to first versus repeated voiding. Females showed no statistically significant variation in either urine flow rate with respect to age, parity or first versus repeated voiding. The maximum and average urine flow rates in both sexes showed an equally strong relationship to voided volume. No artificial restriction of voided volume, e.g. minimum 200 ml, appeared appropriate. These nomograms offer reference ranges for both maximum and average urinary flow rates in both sexes covering a wide range of voided volumes (15-600 ml).