Biomedical subjects

L Brubaker

Publications and source records attributed to L Brubaker.

At least 19 recordsLinked to original sources

PubMed2003

Variability of 24-hour voiding diary variables among asymptomatic women.

PURPOSE: We determine whether urinary diary values are stable over time among women without lower urinary tract symptoms. MATERIALS AND METHODS: Women without lower urinary tract symptoms completed a 24-hour log of fluid intake and volumes voided during June/July 2001 and again during February/March 2002. Initial and repeat diaries were compared using Wilcoxin signed rank tests, considered significant at the 5% level. RESULTS: A total of 137 subjects completed both diaries. Subjects voided a median of 8 times per 24 hours during the first and 7 per 24 hours during the second diary with 95% of subjects recording fewer than 13 voids per 24 hours during both diaries. Nighttime voids were recorded by 59 (43%) subjects during the first and 54 (39%) during the second diary. Urinary frequency and total urine volume were significantly greater during the first than second diary (Z = 2.1, p = 0.03 and Z = 3.3, p = 0.001, respectively). No significant differences in mean voided volume, maximum voided volume, voids per liter intake, total intake, or daytime or nighttime diuresis rates were found when the groups were compared. However, there were large individual differences in all diary variables. CONCLUSIONS: While there is large individual variation in diary values, pooled data from 24-hour urinary diaries concerning voids per liter intake, and mean and maximum voided volumes remain stable. Pooled data concerning raw urinary frequency and urine volumes may vary significantly without any treatment. When urinary frequency is of interest, the number of voids per liter intake may represent the most stable measure.

Adolescent↗

PubMed2002

Bother arising from urinary frequency in women.

Patients commonly express bother with the symptom of frequent urination. The relationship between actual voiding frequency and this symptom is undocumented. We reviewed records of 200 women who had completed 24-hour frequency-volume charts, and had indicated their degree of bother with urinary frequency utilizing the short form of the Urogenital Distress Inventory. The degree of bother was correlated with daytime and nighttime voiding frequency, maximum functional capacity, mean voided volume, and demographic variables. Among 200 women, 180 (90%) indicated at least a minor degree of bother with urinary frequency. A voiding frequency of eight or more times in 24 hours was reported by 166 (83%) of women. Among the 34 women voiding fewer than eight times/24 hours, 26 (76%) reported bother with urinary frequency. There was large variation in the degree of bother reported at a given voiding frequency. Postmenopausal women without hormone replacement therapy (HRT) recorded more nighttime voids than those on HRT. Among postmenopausal women without HRT, mean voided volume and maximum functional capacity were inversely related to patient age. Our study suggests that the currently utilized cutoff value of eight daily voids to define urinary frequency, may not be helpful in the management of women in this country. A racially diverse study of the voiding habits of asymptomatic North American women is mandated.

Adult↗

PubMed2002

Urinary habits among asymptomatic women.

OBJECTIVE: The purpose of this study was to determine normal ranges for voiding diary variables for a racially diverse sample of women without lower urinary tract symptoms in the United States. STUDY DESIGN: Three hundred women without lower urinary tract symptoms completed a 24-hour log of fluid intake and volumes voided. We used linear regression to analyze diary data according to patient characteristics, which included race, age, body mass index, and parity. RESULTS: The following races were represented: black, 118 women (39%); white, 117 women (39%); Hispanic, 36 women (12%); Asian, 28 women (9%); and mixed race, 1 woman (<1%). Subjects voided a median of 8 times in 24 hours; 95% of the subjects recorded fewer than 13 voids per 24 hours. Subjects recorded a median of 4 voids per liter of fluid intake (95% recorded fewer than 9 voids per liter intake) and a median of 5 voids per liter urine output (95% recorded fewer than 12 voids per liter output). Nighttime voids were recorded by 133 subjects (44%). According to current definitions, polyuria was present in 54 subjects (18%). Linear regression showed that the number of voids per 24 hours was related to patient age (beta =.2, P <.001) and fluid intake (beta =.39, P <.001). Mean (beta = -.31, P <.001) and maximum (beta = -.2, P =.003) voided volumes were lower among black women. Voids per liter of fluid intake varied with age (beta =.19, P =.002) and were higher among parous women (beta =.12, P =.003) and Asian women (beta =.17, P =.002). Voids per liter output were lower among black women (beta =.34, P <.001). The number of nighttime voids depended only on patient age (beta =.23, P <.001). CONCLUSION: The results of this multiracial study differ materially from other studies of asymptomatic women. It is probably inappropriate to apply a single set of normative values to all women in the United States because of the significant variability in regional climates and populations.

Adult↗

PubMed2001

The etiology of urinary retention after surgery for genuine stress incontinence.

Transient postoperative urinary retention after stress incontinence surgery is common, and there is no widely accepted method of hastening the return to normal voiding. The etiology of this retention is poorly understood. Failure of the relaxation of the striated external urethral sphincter has been proposed as an etiologic agent, but has not been documented. Ten patients about to undergo a Burch colposuspension or sub-urethral sling, who demonstrated normal preoperative voiding, were recruited to a study of postoperative retention. Hook-wire electromyographic (EMG)probes were placed into the external urethral sphincter while the patients were under anesthesia, and a suprapubic catheter was placed. We performed instrumented voiding trials 1 or 2 days after surgery while continuously recording urethral EMG and intravesical pressure. Two patients demonstrated normal voiding. Two patients were able to void but demonstrated no EMG silencing. Six patients were unable to void and demonstrated persistent EMG activity. Four of these demonstrated no detrusor contraction, whereas two demonstrated detrusor contractions. All patients resumed normal voiding by clinical parameters within 14 days of surgery. Our study supports other research that suggests that failure of relaxation of the striated urethral sphincter contributes to postoperative urinary retention.

Aged↗

PubMed2001

Myosin isoforms in female human detrusor.

The aim of this study was to document the relative proportions of two isoforms of myosin heavy chain in detrusor smooth muscle of women with detrusor overactivity and in asymptomatic controls. Women aged 35-65 with documented detrusor overactivity and without a history of neurologic disease, prior incontinence surgery, elevated post-void residual urine volume, or indwelling urinary catheter were eligible for the study. Full-thickness biopsies of extraperitoneal bladder dome were obtained at the time of laparotomy in six patients with documented detrusor overactivity and in a control group of eight continent patients. Biopsies were frozen in liquid nitrogen, crushed with a frozen mortar and pestle at -80 degrees C, and homogenized in buffer, and the extracts were electrophoresed on 6% polyacrylamide sodium dodecyl sulfate gels and stained with Coomassie blue. The gels were de-stained and then the protein bands were scanned with a densitometer. The mean patient age was 48 years (range, 36-59). Seven patients were Caucasian and seven patients were African American. Detrusor smooth muscle contains a mean of 34% (range, 27-43%) SM1 and 66% (range, 57-73%) SM2 isoforms. There was no difference in isoform composition when patients were compared according to urogynecologic diagnosis or according to race. In detrusor biopsies from women, approximately 34% of myosin is of the SM1 isoform and approximately 66% is of the SM2 isoform. This ratio is relatively constant in the two races studied and unchanged in women with detrusor overactivity. Animal models utilizing outlet obstruction of the bladder to provoke detrusor instability and detrusor hypertrophy are known to alter myosin isoform distribution and may not be appropriate models of detrusor instability in human females.

Adult↗

PubMed2001

The standardization of terminology for researchers in female pelvic floor disorders.

The lack of standardized terminology in pelvic floor disorders (pelvic organ prolapse, urinary incontinence, and fecal incontinence) is a major obstacle to performing and interpreting research. The National Institutes of Health convened the Terminology Workshop for Researchers in Female Pelvic Floor Disorders to: (1) agree on standard terms for defining conditions and outcomes; (2) make recommendations for minimum data collection for research; and (3) identify high priority issues for future research. Pelvic organ prolapse was defined by physical examination staging using the International Continence Society system. Stress urinary incontinence was defined by symptoms and testing; 'cure' was defined as no stress incontinence symptoms, negative testing, and no new problems due to intervention. Overactive bladder was defined as urinary frequency and urgency, with and without urge incontinence. Detrusor instability was defined by cystometry. For all urinary symptoms, defining 'improvement' after intervention was identified as a high priority. For fecal incontinence, more research is needed before recommendations can be made. A standard terminology for research on pelvic floor disorders is presented and areas of high priority for future research are identified.

Fecal Incontinence↗

PubMed2001

Risk factors for an elevated postvoid residual urine volume in women with symptoms of urinary urgency, frequency and urge incontience.

The aim of this study was to identify factors in patients with symptoms of urgency/frequency or urge incontinence that predict that the postvoid residual urine volume (PVR) will be elevated. A restrospective chart review was carried out of all patients new to our urogynecology practice between June 1998 and May 1999, with symptoms of urgency, frequency and/or urge incontinence. Demographic variables, symptoms and physical findings were correlated with the presence of an elevated PVR (>100 ml) using logistic regression analysis. An elevated PVR was found in 10% (33/336) of patients with urge incontinence (UI). and in 5% (3/57) of patients with urgency/frequency without UI. In patients with UI the presence of pelvic organ prolapse (POP) > or = stage II, symptoms of voiding difficulty and the absence of the symptom of stress incontinence, predicted 82% of patients with an elevated PVR.

Adolescent↗

PubMed2001

Donor fascia in urogynaecological procedures: a canine model.

OBJECTIVE: To explore the in vivo characteristics of donor fascia used in urogynaecological procedures, in a canine model. MATERIALS AND METHODS: Two experiments were conducted. In the first, donor fascia grafts were obtained from 12 dogs, the grafts freeze-dried and half were irradiated. The grafts were used for sacrocolpopexy and suburethral slings in each of five dogs. The dogs were killed at 2, 6 and 12 weeks after graft implantation, the grafts retrieved and assessed using tensilometry. In the second experiment, unirradiated sacrocolpopexy grafts were implanted in eight dogs; four grafts were placed under no tension and four under moderate tension. At 8 weeks, the grafts were retrieved and assessed by tensilometry. Measures of strength in both experiments included the ultimate tensile strength, ultimate strain and stiffness. All measures were compared using Kruskal-Wallis nonparametric tests in both studies. RESULTS: In the first experiment, a significant minority (23%) of grafts had complete loss of strength. Measures of graft strength did not vary when analysed according to donor dog, host dog, history of graft irradiation, duration of implantation or location of graft. In the second experiment, grafts placed under no tension tended to have lower tensile strength (chi2(1) = 3.125, P = 0.077), lower stiffness (chi2(1) = 3.125, P = 0.077) and lower ultimate strain (chi 2(1) = 3.182, P = 0.074). CONCLUSION: Graft irradiation as an isolated variable did not predispose grafts to failure in vivo. Biomechanical factors at the implantation site are likely to play a critical role in determining ultimate graft strength.

Animals↗

PubMed2001

Responsiveness of quality of life measurements to change after reconstructive pelvic surgery.

OBJECTIVE: We sought to determine whether Incontinence Impact Questionnaire (IIQ-7) and Urogenital Distress Inventory (UDI-6) scores are sensitive to changes in clinical status after surgery for genuine stress incontinence (GSI) or pelvic organ prolapse (POP). STUDY DESIGN: Patients were included in this study if they had completed the IIQ-7 and UDI-6 scales and had undergone urodynamic testing before and 3 months after surgery for GSI or POP. Kruskal-Wallis tests and logistic regression were used to compare IIQ-7 and UDI-6 scores according to the outcome of surgery. RESULTS: Among 55 patients satisfying inclusion criteria for the study, 34 (62%) underwent Burch colposuspension, and 21 (38%) underwent suburethral sling procedures for GSI; 44 (80%) patients were subjectively continent after surgery. Thirty-four (62%) patients underwent surgical treatment of their POP; 31 (90%) were subjectively cured of their POP symptoms. Mean IIQ-7 and UDI-6 scores were lower in patients who were subjectively continent, and UDI-6 scores were lower in patients who were objectively cured of GSI. CONCLUSION: UDI-6 and IIQ-7 scores change after surgery for GSI and POP, with patients who are subjectively continent having lower postoperative scores on both scales.

Adult↗

PubMed2001

Role of urethral electromyography in predicting outcome of Burch retropubic urethropexy.

OBJECTIVE: To establish preoperative urethral electromyographic parameters that predict which women are unlikely to be cured of genuine stress incontinence by Burch retropubic urethropexy procedures. STUDY DESIGN: Eighty-nine women who underwent preoperative urodynamic testing with urethral electromyography and retropubic urethropexy for genuine stress incontinence were prospectively studied. Raw electromyographic signals were processed by an electromyographic instrument equipped with automated motor unit analysis software programs. Quantitative electromyographic software was used to analyze the electrical activity of the urethral sphincter with use of mean rectified voltage (MRV)-mean amplitude calculated over the entire tracing after the waveform is rectified-with women at rest and during voluntary urethral squeezing, repetitive coughing, and bladder filling. Objective outcomes were determined 3 months after the operation with single-channel cystometrograms performed while subjects were standing. Nonparametric statistical analyses included the chi(2) test of association for nominal data and the Mann-Whitney test for comparison of population medians. RESULTS: All women had urethral hypermobility and met our standard clinical criteria for retropubic urethropexy. Fifteen women had incomplete follow-up data and were excluded from final analysis. Fifty-nine of 74 women (80%) were objectively cured, and 15 women had persistent genuine stress incontinence. Women who were cured did not differ from those who were not cured in age, parity, menopausal status, maximum urethral closure pressure, Valsalva leak point pressure, maximum cystometric capacity, detrusor instability, or prolapse stage. Women with persistent genuine stress incontinence were more likely to have had previous pelvic operations (P =.01). There were no differences in any electromyographic parameters at rest, with urethral squeezing, or during bladder filling between the groups. Women who were objectively cured had larger MRV values with repetitive coughing (P =.05) and larger increases from resting MRV values (DeltaMRV) with repetitive coughing (P =.04). Twenty-seven of 30 women with MRV values > or =25 microV with repetitive coughing were cured (positive predictive value [PPV] = 90%; negative predictive value [NPV] = 32%), and 22 of 24 women with more than a 10-microV increase in resting MRV values with repetitive coughing (DeltaMRV > 10 microV) were cured (PPV = 92%; NPV = 29%). If women had both an MRV value > or =25 microV and a DeltaMRV value >10 microV, the PPV was 100%; however, the NPV remained at 30%. CONCLUSION: Women who were cured of genuine stress incontinence with Burch retropubic urethropexy procedures had better motor unit action potential activation with repetitive coughing than women with persistent genuine stress incontinence. Urethral electromyography may be used to assess the neuromuscular integrity of the striated urethral sphincter and to help predict which women will have successful retropubic urethropexy procedures.

Adult↗

PubMed2000

Editorial comment

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Journal Article↗

PubMed2000

Effects of pudendal nerve injury in the female rat.

To test a neurogenic hypothesis for external urethral sphincter (EUS) dysfunction associated with urinary incontinence, the proximal pudendal nerve was crushed in anesthetized retired breeder female rats (n = 5) and compared with a sham lesion group (n = 4). Outcome measures included concentric needle electromyograms (EMGs) from the target EUS, voiding patterns during a 2-hour dark period, and micturition data over a 24-hour period. Fast Blue (FB) was introduced to the crush site at the time of injury and Diamidino Yellow (DY) to the EUS at the time the rats were killed (3 months post-operative), when histological analysis of the nerve and urethra was also performed. EMG records indicated the EUS motor units undergo typical denervation changes followed by regeneration and recovery. Voiding patterns from the crush group show a significant increase of small urine marks in the front third of the cage. At 1-2 weeks post-op, the frequency of voids was significantly increased in the crush group compared to pre-op and late post-op time periods. The mean volume voided in the light phase at the early post-op time was significantly increased in the sham group. Light and electron microscopic patterns seen in nerve and muscle suggest the regenerating motor units maintain a structural integrity. Motoneurons in the lower lumbar cord were labeled with either DY (14. 5 +/- 6.8), FB (31.7 +/- 23.7), or both (35.0 +/- 17.5) tracers, indicating approximately 54% of the crushed pudendal neurons regenerated to the EUS. In conclusion, several measures suggest this reversible crush lesion induces mild urinary incontinence. This animal model is promising for further development of hypotheses regarding neural injury, the pathogenesis of incontinence, and strategies aimed at prevention and treatment. Neurourol. Urodynam. 19:53-69, 2000.

Animals↗

PubMed2000

Complex repetitive discharges during urethral sphincter EMG: clinical correlates.

Complex repetitive discharges (CRDs) are a form of abnormal needle electromyographic (EMG) activity associated with a variety of neuromuscular disorders, including chronic denervation. Urethral CRDs have also been associated with symptoms of voiding dysfunction. We reviewed the findings of 351 consecutive urethral sphincter EMG studies to characterize the patients with CRDs in our patient population and further to characterize the peri-operative course of any patient with urethral CRDs who underwent surgery for genuine stress incontinence (GSI). Among the 351 women studied, a subgroup of 27 (8%) women demonstrated CRDs during their study. Patients with CRDs were more likely to report the symptom of strain voiding (48% of patients with CRDs, 18% of patients without CRDs; chi(2)((1)) = 17.6, P < 0.001). Patients with CRDs were also more likely to have undergone prior urethral dilation (15% of patients with CRDs versus 2% of patients without CRDs, chi(2)((1)) = 9.5, P < 0.01). Patients with CRDs were similar to patients without CRDs with respect to symptoms of incontinence and history of hysterectomy or surgery for incontinence. Ten patients who had urethral CRDs underwent surgery for their GSI with a 90% success rate. The duration of post-operative catheterization did not differ from that of our general population of patients undergoing similar procedures. Urethral CRDs appear to be a non-specific finding, and it is premature to alter the approach to patients with lower urinary tract dysfunction for this reason.

Action Potentials↗

PubMed2000

Ultrastructure of detrusor and urethral smooth muscle in women with urinary incontinence.

OBJECTIVE: We performed a quantitative study to determine whether mixed urinary incontinence was associated with any ultrastructural changes in detrusor and urethral smooth muscle. STUDY DESIGN: Detrusor and urethral smooth muscle biopsy specimens were obtained at the time of laparotomy from 5 women aged 35 to 65 years with mixed urinary incontinence and from a control group of 5 continent women. Smooth muscle morphologic characteristics were assessed from a systematic random sample of electron micrographs. A further 16 urethral biopsy specimens were similarly analyzed to confirm the findings of the initial study. RESULTS: The electron-dense portion of the sarcolemma was smaller in urethral biopsy specimens taken from patients with intrinsic sphincter deficiency than in those from control subjects (chi(2)((1)) = 4.9; P =.027). No other morphologic characteristics were unique to patients with incontinence. CONCLUSIONS: Our study suggests that focal adhesion architecture is decreased in urethral smooth muscle of patients with intrinsic sphincter deficiency.

Adult↗

PubMed2000

Electrical stimulation in overactive bladder.

Electrical stimulation is an effective and well-tolerated treatment for overactive bladder. Initial work in animals indicated the potential of this treatment, and early clinical experience in Europe further supported its likely efficacy. Although the mechanism of action of electrical stimulation remains unproven in humans, it is believed to be a neuromodulating therapy which affects the neural signaling that controls continence. There is also strong evidence that electrical stimulation affects striated muscle. The therapy can cause hypertrophy of skeletal muscle fibers, possibly by the recruitment of faster-conducting motor units, which would not normally be recruited during voluntary efforts. In addition, electrical stimulation can alter the expression of myosin isoforms, favoring a conversion to type I muscle. Despite our incomplete understanding of the mechanism of action of electrical stimulation, clinical devices have been developed quickly. Case series have been reported throughout Europe. These were followed by controlled clinical trials in the United States. There is good evidence that the use of vaginal electrical stimulators can reduce the occurrence of symptoms of overactive bladder in about half of the patients treated. Multiple uses of nonimplanted stimulation, including thigh stimulation, anal stimulation, and direct pelvic muscle stimulation, have been reported. In these trials, it is common for objective findings to be poorly correlated with subjective reports of improvements or cure. Patients frequently report that the urge-to-leak time improves, but this is difficult to measure objectively. The use of nonimplanted devices is effective and well tolerated, and should precede the use of implanted devices. A direct comparison with other effective methods of treatment for overactive bladder is warranted.

Adult↗

PubMed2000

The antigenicity of fascia lata allografts.

OBJECTIVE: To determine whether commercially available fascia lata allograft material contains donor antigens. MATERIALS AND METHODS: Human leukocyte antigens (HLA) class I and II were assessed in: (i) freeze-dried fascia lata allografts; (ii) a Tutoplast fascia lata graft (Mentor Urology, Santa Barbara, CA, USA); (iii) an acellular dermal graft; and (iv) a successful donor fascia sacrocolpopexy graft one year after implantation, using a polymerase chain reaction sequence-specific primer-based assay. RESULTS: The donor for both the freeze-dried fascia lata and Tutoplast fascia lata was fully HLA-typed. At one year after implantation, antigens from the implanted sacrocolpopexy graft matched the host blood antigens. The antigenicity of the acellular dermal graft could not be ascertained because this material interfered with the assay. CONCLUSION: Donor fascia lata grafts prepared by freeze-drying or by the Tutoplast technique retain donor antigens. The significance of this antigenicity is unknown. All donor antigens are replaced by host antigens after implantation.

Fascia Lata↗

PubMed2000

The fate of rectus fascia suburethral slings.

OBJECTIVE: Autologous rectus fascia is commonly used to construct suburethral slings for the treatment of genuine stress incontinence. This fascia performs well and has not been associated with clinical problems related to its choice as a sling material. However, the histologic appearance of such slings after implantation has not been documented. STUDY DESIGN: At the time of revision of autologous rectus fascia suburethral slings in 5 patients, biopsy specimens of the slings were obtained and submitted for histologic examination. A specimen of rectus fascia before implantation was also obtained from a sixth patient who had no symptoms. RESULTS: After implantation autologous rectus fascia slings remain viable. There is fibroblast proliferation, neovascularization, and remodeling of the graft. No evidence of inflammatory reaction or of graft degeneration was detected. A linear orientation of connective tissue and fibroblasts was seen in some areas, whereas other areas had remodeled to form tissue similar to noninflammatory scar. CONCLUSION: Autologous rectus fascia slings undergo extensive remodeling after implantation.

Aged↗

PubMed2000

Urethral collagen morphologic characteristics among women with genuine stress incontinence.

OBJECTIVE: This was a study of the morphologic characteristics of urethral collagen in women with stress incontinence and continent control women. STUDY DESIGN: Urethral needle biopsy specimens were obtained from 31 women. Fifteen women were continent, and the other 16 had undergone full urogynecologic assessment for symptoms of urinary incontinence. Biopsy specimens were assessed under electron microscopy. Mean collagen fibril diameter was measured and collagen morphologic characteristics were assessed. RESULTS: The biopsy specimens from 30 women were included in the analysis. Collagen fibril diameter did not vary with continence status, the presence of pelvic organ prolapse, age, race or hormonal status. Alterations in collagen fibril morphologic characteristics were evident in the biopsy specimens from nine patients with incontinence. The alterations in collagen morphologic characteristics fell into three patterns, which for convenience were referred to as the obscured pattern, the dense pattern, and the degenerative pattern. CONCLUSION: Altered collagen morphologic characteristics are found in some patients with stress incontinence, and possible causes for those alterations are suggested by their appearances.

Adult↗