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D Z Lubowski

Publications and source records attributed to D Z Lubowski.

At least 19 recordsLinked to original sources

Sacral nerve stimulation induces pan-colonic propagating pressure waves and increases defecation frequency in patients with slow-transit constipation.

OBJECTIVE: Colonic propagating sequences are important for normal colonic transit and defecation. The frequency of these motor patterns is reduced in slow-transit constipation. Sacral nerve stimulation (SNS) is a useful treatment for fecal and urinary incontinence. A high proportion of these patients have also reported altered bowel function. The effects of SNS on colonic propagating sequences in constipation are unknown. Our aims were to evaluate the effect of SNS on colonic pressure patterns and evaluate its therapeutic potential in severe constipation. METHOD: In eight patients with scintigraphically confirmed slow-transit constipation, a manometry catheter (16 recording sites at 7.5 cm intervals) was positioned colonoscopically and the tip fixed in the caecum. Temporary electrodes (Medtronic) were implanted in the S2 and S3 sacral nerve foramina under general anaesthesia. In the fasted state, 14 Hz stimulation was administered and four sets of parameters (pulse width 300 or 400 micros; S2 and S3) were tested in four 2-h epochs, in random order, over 2 days. Patients were then discharged home with the sacral wires in situ and a 3-week trial stimulation commenced during which patients completed a daily stool diary. RESULTS: When compared with basal activity, electrical stimulation to S3 significantly increased pan-colonic antegrade propagating sequence (PS) frequency (5.4 +/- 4.2 vs 11.3 +/- 6.6 PS/h; P=0.01). Stimulation at S2 significantly increased retrograde PSs (basal 2.6 +/- 1.8 vs SNS 5.6 +/- 4.8 PS/h; P=0.03). During the subsequent three-week trial (continuous stimulation), six of eight reported increased bowel frequency with a reduction in laxative usage. CONCLUSION: These data demonstrate that SNS induces pan-colonic propagating pressure waves and therefore shows promise as a potential therapy for severe refractory constipation.

Adult↗

Rigid sigmoidoscopy: a potential hazard for cross-contamination.

BACKGROUND: Rigid sigmoidoscopy using a disposable or nondisposable sigmoidoscope is a common outpatient procedure. It has been assumed that the nondisposable bellows and light head of the sigmoidoscope remain free from enteric organisms so that the procedure is sterile if a disposable or nondisposable (metal) sigmoidoscope shaft is used. The aim of this study was to identify the presence of organisms within the bellows or light head of the sigmoidoscope. METHODS: Of 21 patients undergoing rigid sigmoidoscopy with a disposable instrument, bacterial cultures were taken from the inside of sterile Jackson-Pratt bulbs in 12 patients, with the bulbs being used to simulate the nondisposable insufflation bellows. In an additional nine patients, swabs were taken for culture from the inside of the nondisposable light head. RESULTS: Enteric gram-negative Escherichia coli and mixed anaerobic organisms were cultured from the Jackson-Pratt bulbs in two cases, and gram-positive organisms were cultured in another case. Gram-negative organisms, including Bacillus, Proteus mirabilis, Klebsiella, and Enterococcus faecalis, were cultured from the inside of the light head in two cases. CONCLUSION: Sigmoidoscopy using a disposable instrument is not a sterile procedure and may pose a risk of patient-to-patient cross-contamination by potentially harboring organisms in the bellows or light head.

Cross Infection↗

Extracorporeal magnetic stimulation of the pelvic floor: impact on anorectal function and physiology. A pilot study.

PURPOSE: This study was designed to investigate the effect of extracorporeal magnetic stimulation on anorectal function and physiology. METHODS: A pilot study comparing the physiology of ten incontinent (9 females) and five continent (4 females) patients with and without perineal magnetic stimulation (10 Hz and 50 Hz) was performed. The ten incontinent patients were treated with two sessions weekly for five weeks of perineal magnetic stimulation. At treatment completion, precontinent and postcontinent scores and resting and squeeze anal pressure were compared. Patients also reported symptom improvement and satisfaction on a linear analog scale. RESULTS: The patients' mean age was 57 years. Sitting resting and squeeze anal pressures were significantly greater than lying pressures (P = 0.007, 0.047). Both 10-Hz and 50-Hz stimulation effected a significant increase in anal pressures compared with the baseline resting pressure (P = 0.005). The baseline squeeze pressures were significantly higher than the stimulated pressures compared with 50-Hz pressures (P = 0.022). After six weeks of treatment, there was a statistically significant increase in resting and squeeze anal pressures and a significant decrease in continence scores (P = 0.007, P = 0.008, P = 0.017). The mean percentage subjective improvement was 16 percent, and the mean patient satisfaction score was 3.3, positively correlating with an improvement in the continence score. CONCLUSIONS: Extracorporeal magnetic stimulation results in a significant increase in anal resting pressure irrespective of pretreatment continence. Although the subjective improvement in continence after treatment is small, there is a significant improvement in both resting pressures and patient continence scores.

Anal Canal↗

Long-term follow-up of dynamic graciloplasty for faecal incontinence.

OBJECTIVE: This paper presents the long-term morbidity, function and quality of life data for patients who have undergone dynamic graciloplasty (DGP) for faecal incontinence. PATIENTS AND METHODS: All patients (n = 38) who had undergone DGP at one institution between 1993 and 2003 are presented. Thirty-three were available for long-term follow-up (median 60 months) and completed a telephone questionnaire assessing quality of life (QOL), bowel and sexual function and patient satisfaction. All patients had interval anorectal physiology studies. RESULTS: At a median follow-up of 5 years, 72% had pain, swelling or paraesthesia in the donor leg and 27% had sexual dysfunction. Sixteen percent of patients had been converted to an end-colostomy for persisting incontinence and 11% for obstructed defaecation. All other patients have a normally functioning graciloplasty. Sixteen percent of patients reported a faecal continence score < 12. Of those patients with a functioning graciloplasty, 50% had obstructed defaecation and 64% reported that their bowel dysfunction had a negative impacted on their QOL. Age, medical comorbidity and anal manometry did not correlate with functional outcome. Quality of life scores and patient satisfaction scores correlated significantly with continence scores. There was a trend toward higher QOL and satisfaction scores with conversion to colostomy compared with a continence score > 12. Sixty percent of patients rated their satisfaction with DGP as 50% or better on a visual analogue scale, and this correlated strongly with the continence score at the time of the assessment (P < 0.001). CONCLUSION: Dynamic graciloplasty significantly improves patient quality of life and anal continence for some patients. Despite increased experience, morbidity remains high and long-term continence scores are poor in a majority of cases. Obstructed defaecation is a significant problem after graciloplasty and antegrade colonic enemas may be needed. Significant prognostic factors for obstructed defaecation remain to be identified. The mechanism of both continence failure and surgical morbidity remains poorly defined in many patients and requires further investigation. The individual patient can expect a 16% chance of normal faecal continence at 5 years, with at least one surgical morbidity as a result of the procedure.

Adolescent↗

Transanal endoscopic microsurgery excision: is anorectal function compromised?

PURPOSE: Transanal endoscopic microsurgery is a new technique that has not yet found its place in routine practice. The procedure results in dilation of the anal sphincter with a large-diameter operating sigmoidoscope, sometimes for a prolonged period. The purpose of the present study was to assess the effect of transanal endoscopic microsurgery on anorectal function. METHODS: Eighteen consecutive patients undergoing transanal endoscopic microsurgery excision of rectal tumors, of whom 13 were available for evaluation, were included. Continence was scored by a numeric scale before surgery and at three and six weeks after surgery. Anorectal physiology studies were performed preoperatively and six weeks postoperatively with manometry, pudendal nerve motor terminal latency, anal mucosal electrosensitivity, rectal balloon volume studies, and endoanal ultrasound. RESULTS: There was a significant reduction in mean anal resting pressure (104 +/- 32 cm H2O before surgery, 73 +/- 30 cm H2O after surgery; P = 0.0009). There was no significant change in squeeze or cough pressure, pudendal nerve terminal motor latency, anal mucosal electrosensitivity, or rectal balloon study volumes. Fall in resting pressure was significantly correlated with length of operating time (r2 =0.39, P = 0.047). There was no significant change in mean continence score after surgery. CONCLUSION: Transanal endoscopic microsurgery results in a reduction in internal sphincter tone. This did not affect continence in a short-term study.

Adult↗

Neuropeptides and nerve growth in inflammatory bowel diseases: a quantitative immunohistochemical study.

Many studies have indicated changes in neuropeptides in inflammatory bowel disease (IBD), but with contradictory results. Nerve growth factor also has a potential role in the maintenance of enteric nerves and may be associated with IBD. A quantitative immunohistochemical method was used to measure area density of immunoreactive nerves in the colonic mucosa of surgical specimens. No significant differences in immunoreactivity for substance P, vasoactive intestinal polypeptide, growth associated protein 43, and the neurotrophin receptor p75 were seen in the control, Crohn's, and ulcerative colitis groups. Compared to age-matched normal colon (N = 18), there was an increase in neutrophil number in Crohn's (P < 0.05) and ulcerative colitis (P < 0.01) (both N = 9). There were positive correlations (P < 0.05) between neutrophil number and growth associated protein, between p75 and substance P immunoreactive nerves in ulcerative colitis, and between p75 and vasoactive intestinal polypeptide in Crohn's specimens. These data indicate a link between the immunologic and nervous systems in IBD.

Adult↗

The proximal colonic motor response to rectal mechanical and chemical stimulation.

We aimed to determine whether rectal distension and/or infusion of bile acids stimulates propagating or nonpropagating activity in the unprepared proximal colon in 10 healthy volunteers using a nasocolonic manometric catheter (16 recording sites at 7.5-cm spacing). Sensory thresholds and proximal colonic motor responses were assessed following rectal distension by balloon inflation and rectal instillation of chenodeoxycholic acid. Maximum tolerated balloon volume and the volume that stimulated a desire to defecate were both significantly (P < 0.01) reduced after rectal chenodeoxycholic acid. The frequency of colonic propagating pressure wave sequences decreased significantly in response to initial balloon inflations (P < 0.05), but the frequency doubled after subsequent chenodeoxycholic acid infusion (P < 0.002). Nonpropagating activity decreased after balloon inflation, was not influenced by acid infusion, and demonstrated a further decrease in response to repeat balloon inflation. We concluded that rectal chenodeoxycholic acid in physiological concentrations is a potent stimulus for propagating pressure waves arising in the proximal colon and reduces rectal sensory thresholds. Rectal distension inhibits all colonic motor activity.

Adult↗

Clostridium septicum and malignancy.

BACKGROUND: Clostridium septicum is known to be associated with malignancy or immunosuppression. It has a variable clinical presentation and is associated with a high mortality. The aim of the present study was to review the experience at St George Hospital, Sydney, over a 10-year period, with particular reference to the association of this condition with colorectal cancer. METHODS: The records of five patients with blood culture-proven Clostridium septicum infection, among a larger group of 31 patients with clostridial infections, presenting to St George Hospital between 1990 and 2000 were reviewed. RESULTS: Associated malignancy was found in four (80%) of the patients with Clostridium septicum infection. Two infections were related to colorectal cancer, two to haematological malignancies and one to radiation-induced recto-urethral fistula. Those patients who had colorectal cancer presented with septicaemia and vague abdominal symptoms. CONCLUSIONS: Clostridium septicum infections have a strong association with malignancy. When this infection occurs without an obvious underlying aetiology there should be a high index of suspicion about associated malignancy. In the absence of haematological malignancy a colonoscopy is warranted. Early diagnosis and aggressive treatment is essential in order to improve prognosis.

Adult↗

Do patients assess rectal bleeding accurately?

BACKGROUND: The accuracy of a patient's assessment of the volume of blood passed per rectum is unknown. The aim of the present study was to compare subjective estimations with known amounts of blood. METHODS: Thirty subjects (10 patients, 10 nurses and 10 doctors) made a visual estimation of four volumes of blood (0.25 mL, 10 mL, 50 mL, 200 mL), each placed in a standardized way into a toilet bowl. Subjects gave their estimations in mL, and also by drawing a line on a cup at the level to which they estimated that the amount of blood would fill the cup. Statistical analysis was carried out using Student's t-test. Multiple comparisons were analysed by anova. RESULTS: There was no significant difference between the groups in their estimations of each of the four volumes. Each group made a statistically significant overestimation for the 0.25 mL, 10 mL and 50 mL volumes with cup marking, as well as with estimation in mL (except for patients with the 50 mL volume, where there was a non-significant overestimation). For the 200 mL volume, patients and doctors made statistically significant underestimations with cup marking, but for nurses the underestimation did not reach significance. For the 200 mL volume estimations in mL, both nurses and doctors made underestimations that were not significant. CONCLUSIONS: Small to moderate amounts of blood in the toilet bowl are subjectively significantly overestimated, whereas larger volumes tend to be underestimated. This may have implications for the management of patients presenting with rectal bleeding.

Adult↗

Prolonged multi-point recording of colonic manometry in the unprepared human colon: providing insight into potentially relevant pressure wave parameters.

OBJECTIVES: To determine the feasibility of and derive normative data for prolonged, 24-h, multipoint, closely spaced, water perfused manometry of the unprepared human colon. METHODS: In 14 healthy volunteers, 24-h recordings were made using a water perfused, balloon-tipped, 17 lumen catheter which was passed pernasally and positioned so that 16 recording sites spanned the colon at 7.5 cm intervals from cecum to rectum. The area under the pressure curve and propagating pressure wave parameters were quantified for the 16 regions. High amplitude propagating sequences were defined as were rectal motor complexes. RESULTS: Nasocolonic recording was well tolerated and achievable. Propagation sequences, including high amplitude propagating sequences, originated in the cecum (0.32 +/- 0.05/h) more frequently than in other regions and the extent of propagation correlated significantly with proximity of the site of sequence origin to the cecum (p < 0.001). Propagation velocity of propagating sequences was greater than high amplitude propagating sequences (p = 0.0002) and region-dependent, unlike high amplitude propagating sequences (p < 0.01). The frequency of propagating sequences did not increase after the meal, but frequency of high amplitude propagating sequences was increased significantly by the meal (p < 0.01). Rectal motor complexes were seen throughout the colon with no apparent periodicity. CONCLUSIONS: Prolonged, multipoint, perfusion manometry of the unprepared colon provides improved spatial resolution of colonic motor patterns and confirms the diurnal and regional variations in propagating pressure waves detected in the prepared colon. The study demonstrates differences between high amplitude propagating sequences and propagating sequence parameters that may have functional significance; and also, that the rectal motor complex is a ubiquitous pan colonic motor pattern.

Adult↗

Oral sodium phosphate solution is a superior colonoscopy preparation to polyethylene glycol with bisacodyl.

PURPOSE: The aim of this study was to compare the efficacy and patient tolerance of two bowel preparations for colonoscopy. METHODS: Three hundred twenty-three consecutive patients undergoing colonoscopy were randomly assigned to receive either oral sodium phosphate, or 2 liters of polyethylene glycol solution preceded by the stimulant laxative bisacodyl. Patients were asked to record the effects of the preparation, noting any vomiting, nausea, or abdominal pain, and to determine a discomfort rating on a scale of 1 to 5. One hundred sixty-nine patients were assigned to the oral sodium phosphate solution, and 154 to polyethylene glycol with bisacodyl. Surgeons were blinded to the preparation used and rated the quality of the bowel preparation on a scale of 1 to 5. RESULTS: Ninety-nine percent of patients in the sodium phosphate group drank all of the solution as opposed to 91 percent of patients in the polyethylene glycol with bisacodyl group. Patients in the sodium phosphate group reported significantly less discomfort (P = 0.002). No significant difference was reported for vomiting, nausea, or abdominal pain associated with the preparations. The quality of bowel cleansing was considered by the colonoscopists significantly better for the sodium phosphate group than the polyethylene glycol with bisacodyl group (P < 0.000001). CONCLUSIONS: Colonoscopy preparation with sodium phosphate solution is better tolerated and more effective than polyethylene glycol with bisacodyl.

Administration, Oral↗

Standards for anal sphincter replacement.

PURPOSE: Anal sphincter replacement offers a new treatment option for patients with severe refractory fecal incontinence or for those who require abdominoperineal resection for localized malignancy. The purpose of this study was to review the current status of anal sphincter replacement, formulate a consensus statement regarding its current use, and outline suggestions for future development. METHODS: Four areas of interests were selected: indications for sphincter replacement, continence scoring and quality of life, choice of therapy, and dissemination of new technology. A questionnaire regarding these issues was developed and circulated to working party members; its results served as the basis for this consensus document. RESULTS: Both electrically stimulated skeletal muscle neosphincter and artificial anal sphincter are options for patients with end-stage fecal incontinence. Electrically stimulated skeletal muscle neosphincter is also appropriate for reconstruction after surgical excision of the anorectum in selected cases. Avoidance of complications requires strict attention to sterile technique, prophylactic antibiotics, and deep venous thrombus prophylaxis. A standardized scoring system is proposed that evaluates both continence and evacuation. Quality of life is a critical endpoint for assessing sphincter replacement, and use of The American Society of Colon and Rectal Surgeons incontinence-specific quality-of-life instrument is recommended. As the efficacy of sphincter replacement becomes proven, dissemination of the technique should occur in a controlled manner to ensure adequate surgeon training, minimization of complications, and optimization of results. CONCLUSIONS: Sphincter replacement by electrically stimulated skeletal muscle neosphincter and artificial anal sphincter provide a continent option for patients with end-stage fecal incontinence and those requiring abdominoperineal resection. The guidelines offered in this document are intended to facilitate the controlled and safe development and acceptance of these new techniques.

Anal Canal↗

Circular muscle contraction, messenger signalling and localization of binding sites for neurokinin A in human sigmoid colon.

1. Neurokinin (NK)A is the endogenous ligand for the tachykinin NK2 receptor. In the present study, tachykinins and selective receptor agonists were tested as contractile agonists in human colon circular muscle and [125I]-NKA was used to localize binding sites in human colon. 2. In strips of circular muscle, removal of mucosa and submucosa significantly (P < 0.05) increased the potency and the maximum response achieved by NKA. 3. The rank order of potency of tachykinin and selective receptor agonists in contracting circular muscle strips was NKA > or = [Lys5,MeLeu9,Nle10]NKA(4-10) > or = neuropeptide (NP)gamma > or = [betaAla8]NKA(4-10) >> NKB > substance P (SP) >> senktide approximate to [Pro9]SP. 4. Specific binding sites for [125I]-NKA were densely localized over circular muscle and muscularis mucosae. Weak specific binding was seen on longitudinal muscle and taenia coli, whereas no binding sites were seen on mucosa, ganglia or blood vessels. 5. In circular muscle, the selective NK2 receptor agonist [LysS,MeLeu9,Nle10]NKA(4-10) produced weak increases (maximum 37%) in inositol monophosphate formation with a pD2 of 6.8+/-0.51 (n = 3). Carbachol (100 micromol/L) was also a weak stimulant (maximum 45%). These agonists were over 10-fold more efficacious in stimulation of inositol monophosphate in rat urinary bladder. 6. In conclusion, [125I]-NKA binding sites localized on human colon circular muscle were characterized as NK2 receptors. Functionally, the tachykinin NK2 receptor is mediating circular smooth muscle contraction. Although the human NK2 receptor is coupled to the phosphatidylinositol pathway, other second messenger mechanisms may also operate in this tissue.

Aged↗

Spatial and temporal organization of pressure patterns throughout the unprepared colon during spontaneous defecation.

OBJECTIVE: The aim of this study was to examine colonic motor events associated with spontaneous defecation in the entire unprepared human colon under physiological conditions. METHODS: In 13 healthy volunteers a perfused, balloon-tipped, 17-lumen catheter (outer diameter, 3.5 mm; intersidehole spacing, 7.5 cm) was passed pernasally and positioned in the distal unprepared colon. RESULTS: In the hour before spontaneous defecation, there was an increase in propagating sequence frequency (p = 0.04) and nonpropagating activity when compared to basal conditions (p < 0.0001). During this hour the spatial and temporal relationships among propagating sequences demonstrated a biphasic pattern. Both the early (proximal) and late (distal) colonic phases involved the whole colon and were characterized by respective antegrade and retrograde migration of site-of-origin of arrays of propagating sequences. There was a negative correlation between propagating sequence amplitude and the time interval from propagating sequence to stool expulsion (p = 0.008). CONCLUSIONS: The colonic motor correlate of defecation is the colonic propagating sequence, the frequency and amplitude of which begin to increase as early as 1 h before stool expulsion. During the preexpulsive phase, the spatial and temporal relationship among the sites of origin of individual propagating sequences demonstrate a stereotypic anal followed by orad migration, which raises the possibility of control by long colocolonic pathways.

Adult↗