Traditional measures of normal anal sphincter function using high-resolution anorectal manometry (HRAM) in 115 healthy volunteers.

BACKGROUND: High-resolution anorectal manometry (HRAM) is a relatively new method for collection and interpretation of data relevant to sphincteric function, and for the first time allows a global appreciation of the anorectum as a functional unit. Historically, traditional anal manometry has been plagued by lack of standardization and healthy volunteer data of variable quality. The aims of this study were: (i) to obtain normative data sets for traditional measures of anorectal function using HRAM in healthy subjects and; (ii) to qualitatively describe novel physiological phenomena, which may be of future relevance when this method is applied to patients. METHODS: 115 healthy subjects (96 female) underwent HRAM using a 10 channel, 12F solid-state catheter. Measurements were performed during rest, squeeze, cough, and simulated defecation (push). Data were displayed as color contour plots and analysed using a commercially available manometric system (Solar GI HRM v9.1, Medical Measurement Systems). Associations between age, gender and parity were subsequently explored. KEY RESULTS: HRAM color contour plots provided clear delineation of the high-pressure zone within the anal canal and showed recruitment during maneuvers that altered intra-anal pressures. Automated analysis produced quantitative data, which have been presented on the basis of gender and parity due to the effect of these covariates on some sphincter functions. In line with traditional manometry, some age and gender differences were seen. Males had a greater functional anal canal length and anal pressures during the cough maneuver. Parity in females was associated with reduced squeeze increments. CONCLUSIONS & INFERENCES: The study provides a large healthy volunteer dataset and parameters of traditional measures of anorectal function. A number of novel phenomena are appreciated, the significance of which will require further analysis and comparisons with patient populations.

Temporary gastric neuromodulation for intractable nausea and vomiting.

INTRODUCTION: Gastric neuromodulation (GNM) has been advocated for the treatment of drug refractory gastroparesis or persistent nausea and vomiting in the absence of a mechanical bowel obstruction. There is, however, little in the way of objective data to support its use, particularly with regards to its effects on gastric emptying. METHODS: Six patients (male-to-female ratio: 4:2, mean age: 49 years, range: 44-57 years) underwent the GNM between April and August 2010. Three patients had confirmed slow gastrointestinal transit. Aetiology included previous gastric surgery in two, diabetes in one and idiopathic nausea and vomiting in three patients. GNM pacing wires were placed endoscopically and left in situ for seven days. Patients underwent gastric scintigraphy before and 24 hours after the commencement of GNM. Total gastroparesis symptom scores (TSS), weekly vomiting frequency scores (VFS), health-related quality of life (using the SF-12(®) questionnaire), gastric emptying, nutritional status and weight were compared before and after GNM. RESULTS: TSS improved after GNM in comparison with baseline data. VFS improved in three of four symptomatic patients. The SF-12(®) physical composite score improved in four patients (27.5 vs 34.3) and the mental composite score improved in five patients (34.9 vs 35.9). All patients reported an improvement in oral intake. A significant weight gain (mean: 1kg, range: 0.3-2.4kg) was observed over seven days. Gastric emptying half-time improved in four patients. CONCLUSIONS: GNM improved upper gastrointestinal symptoms, quality of life and nutritional status in patients with intractable nausea and vomiting. GNM merits further investigation.

Injectable anal bulking agent for the management of faecal incontinence.

This study was conducted to determine the safety and efficacy of injectable bulking agents. A total of 13 procedures were performed on 11 patients with faecal incontinence during 2002 to 2007. Patients with internal anal sphincter defect and low incontinence score (Cleveland score < 10) revealed improvement. Patients with higher incontinence score and external sphincter defect secondary to obstetric damage required further intervention. At a median follow-up of 43 months, 7 (63%) patients showed improvement in incontinence score and 4 (32%) showed marked improvement in their symptoms. Fifty six percent of the patients described this as an effective procedure, though the level of effectiveness varied from person to person. Anal injectable collagen was found safe and effective in the management of faecal incontinence. Long-term follow-ups are required to re assess and consider definitive procedure in failed cases.

Randomized controlled trial of patient-controlled sedation for colonoscopy: Entonox vs modified patient-maintained target-controlled propofol.

AIM: Propofol sedation is often associated with deep sedation and decreased manoeuvrability. Patient-maintained sedation has been used in such patients with minimal side-effects. We aimed to compare novel modified patient-maintained target-controlled infusion (TCI) of propofol with patient-controlled Entonox inhalation for colonoscopy in terms of analgesic efficacy (primary outcome), depth of sedation, manoeuvrability and patient and endoscopist satisfaction (secondary outcomes). METHOD: One hundred patients undergoing elective colonoscopy were randomized to receive either TCI propofol or Entonox. Patients in the propofol group were administered propofol initially to achieve a target concentration of 1.2 µg/ml and then allowed to self-administer a bolus of propofol (200 µg/kg/ml) using a patient-controlled analgesia pump with a handset. Entonox group patients inhaled the gas through a mouthpiece until caecum was reached and then as required. Sedation was initially given by an anaesthetist to achieve a score of 4 (Modified Observer's Assessment of Alertness and Sedation Scale), and colonoscopy was then started. Patients completed an anxiety score (Hospital Anxiety and Depression questionnaire), a baseline letter cancellation test and a pain score on a 100-mm visual analogue scale before and after the procedure. All patients completed a satisfaction survey at discharge and 24 h postprocedure. RESULTS: The median dose of propofol was 174 mg, and the median number of propofol boluses was four. There was no difference between the two groups in terms of pain recorded (95% confidence interval of the difference -0.809, 5.02) and patient/endoscopist satisfaction. There was no difference between the two groups in either depth of sedation or manoeuvrability. CONCLUSION: Both Entonox and the modified TCI propofol provide equally effective sedation and pain relief, simultaneously allowing patients to be easily manoeuvred during the procedures.

Sacral neuromodulation for the treatment of faecal incontinence in a patient with organophosphate poisoning.

Faecal incontinence is a debilitating condition. Sacral neuromodulation may have a role in the treatment of faecal incontinence. We report a case of faecal incontinence secondary to chronic organophosphate poisoning, which was successfully treated with sacral neuromodulation. The patient's faecal incontinence and quality of life improved significantly.

Artificial neural networks to predict presence of significant pathology in patients presenting to routine colorectal clinics.

AIM: Artificial neural networks (ANNs) are computer programs used to identify complex relations within data. Routine predictions of presence of colorectal pathology based on population statistics have little meaning for individual patient. This results in large number of unnecessary lower gastrointestinal endoscopies (LGEs - colonoscopies and flexible sigmoidoscopies). We aimed to develop a neural network algorithm that can accurately predict presence of significant pathology in patients attending routine outpatient clinics for gastrointestinal symptoms. METHOD: Ethics approval was obtained and the study was monitored according to International Committee on Harmonisation - Good Clinical Practice (ICH-GCP) standards. Three-hundred patients undergoing LGE prospectively completed a specifically developed questionnaire, which included 40 variables based on clinical symptoms, signs, past- and family history. Complete data sets of 100 patients were used to train the ANN; the remaining data was used for internal validation. The primary output used was positive finding on LGE, including polyps, cancer, diverticular disease or colitis. For external validation, the ANN was applied to data from 50 patients in primary care and also compared with the predictions of four clinicians. RESULTS: Clear correlation between actual data value and ANN predictions were found (r = 0.931; P = 0.0001). The predictive accuracy of ANN was 95% in training group and 90% (95% CI 84-96) in the internal validation set and this was significantly higher than the clinical accuracy (75%). ANN also showed high accuracy in the external validation group (89%). CONCLUSION: Artificial neural networks offer the possibility of personal prediction of outcome for individual patients presenting in clinics with colorectal symptoms, making it possible to make more appropriate requests for lower gastrointestinal endoscopy.

Patient satisfaction with lower gastrointestinal endoscopy: doctors, nurse and nonmedical endoscopists.

AIM: Assessment of patient satisfaction with lower gastrointestinal endoscopy (LGE) comprising colonoscopy and flexible sigmoidoscopy is gaining increasing importance. We have now trained non healthcare professionals such as nonmedical endoscopists (NMEs) to perform LGE to overcome shortage of trained endoscopists. The aim of this study was to prospectively determine patient satisfaction, factors affecting satisfaction with LGE and to compare with nurses, NME and medical endoscopists, in terms of patient satisfaction. METHOD: Consecutive patients undergoing LGE answered specially developed patient satisfaction questionnaire at discharge and 24 h thereafter. This questionnaire was a modification of m-Group Health Association of America questionnaire. Construct and face validity of questionnaire were tested by an expert group. Demographic and clinical data was prospectively collected. Multivariate regression analysis was performed to determine factors influencing patient satisfaction. RESULTS: Some 503 patients were surveyed after LGE. Examinations were performed by nurse (n = 105), doctor (n = 191), or NMEs (n = 155). There were no differences between three groups in terms of completion rates/complications. No differences were detected between endoscopists in patient rating for overall satisfaction (P = 0.6), technical skills (P = 0.58), communication skills (P = 0.61) or interpersonal skills (0.59). Multivariate regression analysis showed that higher preprocedure anxiety, history of pelvic operations/hysterectomy and higher pain scores were associated with adverse patient satisfaction and preprocedure anxiety, history of hysterectomy and female gender were associated with higher pain scores. CONCLUSION: This study has shown that there are no differences in patient satisfaction with LGE performed by nurse, doctor or NME. The most important factor affecting patient satisfaction is degree of discomfort/pain experienced by patient.

Quality assurance in colonoscopy: role of endomucosal clips.

OBJECTIVE: Quality assurance in colonoscopy is important, and subjective assessment of completion based on endoscopic signs can be inaccurate leading to missed lesions. We aimed to determine the technique of endomucosal clips with follow-up X-rays in objectively documenting completion and correlation with pathology miss rates. METHOD: A total of 82 patients undergoing colonoscopy by trained colonoscopists had an endomucosal clip applied to the most proximal bowel reached. A plain abdominal X-ray was performed while there was still a pneumocolon, and the clip position was assessed by a blinded radiologist to determine objective completion rates. Repeat colonoscopies were performed in patients with incomplete procedures. Pathology and endoscopy database were also reviewed to identify missed lesions at a median follow-up of 6 years. These were correlated with colonoscopy completions. RESULTS: The clip was found in caecum of 76 (93%), ascending-colon in three (3.6%), hepatic flexure in one (1.2%) and splenic flexure in two (2.4%) patients. The endoscopist opinion was incorrect in six incomplete colonoscopies. A total of 33 patients underwent repeat colonoscopies over the median 6-year follow-up. Three adenomas and one carcinoma were missed in the incomplete group and were subsequently picked up in repeat endoscopies. Only one adenoma was truly missed in complete colonoscopies, providing an overall miss rate of 1.3%. CONCLUSION: Use of endomucosal clips with follow-on abdominal X-ray is a safe and effective method of determining completion of colonoscopy. This technique is also an excellent objective measure of quality assurance of completion and miss rates in colonoscopy, especially when combined with an audit to determine the missed lesions at two years postprocedure.

Randomized clinical trial of Entonox versus midazolam-fentanyl sedation for colonoscopy.

BACKGROUND: Intravenous sedation for colonoscopy is associated with cardiorespiratory complications and delayed recovery. The aim of this randomized clinical trial was to compare the efficacy of Entonox (50 per cent nitrous oxide and 50 per cent oxygen) and intravenous sedation using midazolam-fentanyl for colonoscopy. METHODS: Some 131 patients undergoing elective colonoscopy were included. Patients completed a Hospital Anxiety and Depression questionnaire, letter cancellation tests and pain scores on a 100-mm visual analogue scale before, immediately after the procedure and at discharge. They also completed a satisfaction survey at discharge and 24 h after the procedure. RESULTS: Sixty-five patients were randomized to receive Entonox and 66 to midazolam-fentanyl. Completion rates were similar (94 versus 92 per cent respectively; P = 0.513). Patients receiving Entonox had a shorter time to discharge. They reported significantly less pain (mean score 16.7 versus 40.1; P < 0.001), and showed better recovery of psychomotor function immediately after the procedure and at discharge. Patient satisfaction was higher among patients who received Entonox (median score 96 versus 89; P = 0.001). CONCLUSION: Entonox provides better pain relief and faster recovery than midazolam-fentanyl and so is more effective for colonoscopy.

The prevalence of occult obstetric anal sphincter injury following childbirth--literature review.

OBJECTIVE: To calculate the published prevalence of ultrasound-detected occult anal sphincter damage associated with different modes of delivery. METHODS: A search of the English language literature for articles using keywords describing the prevalence of ultrasound-diagnosed anal sphincter injury following childbirth. The weighted mean prevalence of occult anal sphincter injury was calculated in the following groups: (1) primiparous women (unselected); (2) primiparous women after an unassisted normal vaginal delivery; (3) multiparous women (unselected); (4) following forceps delivery; (5) following ventouse delivery; (6) following cesarean section. RESULTS: Nineteen articles described ultrasound-diagnosed occult anal sphincter injury. The prevalence in unselected primiparous women (excluding cesarean section) was 29.2% (288/983). After unassisted vaginal delivery in primiparae the prevalence was 21.7% (74/341). The incidence in multiparous women (unselected) is 32.3% (107/331); following forceps delivery 49.1% (131/267) and with ventouse delivery it is 45.2% (66/146). Only one woman (in 173 cases) had anal sphincter injury following cesarean section. CONCLUSIONS: After a review of the literature, occult anal sphincter injury is mostly associated with the first vaginal delivery and is particularly high following instrumental deliveries. Ventouse is less traumatic than forceps. Cesarean section is protective to the anal sphincter.

Investigation and treatment of faecal incontinence.

Faecal incontinence is a debilitating condition affecting people of all ages, and significantly impairs quality of life. Proper clinical assessment followed by conservative medical therapy leads to improvement in more than 50% of cases, including patients with severe symptoms. Patients with advanced incontinence or those resistant to initial treatment should be evaluated by anorectal physiology testing to establish the severity and type of incontinence. Several treatment options with promising results exist. Patients with gross sphincter defects should undergo surgical repair. Those who fail to respond to sphincteroplasty and those with no anatomical defects have the option of either sacral nerve stimulation or other advanced procedures. Stoma formation should be reserved for patients who do not respond to any of the above procedures.

Endoscopic mucosal resection (EMR) in the management of large colo-rectal polyps.

BACKGROUND: Colonoscopic polypectomy plays a major role in preventing colo-rectal cancer. However, resection of sessile, broad-based pedunculated and flat lesions carries a high risk of perforation. Endoscopic Mucosal Resection (EMR) may significantly reduce this risk. We aim to assess the safety and efficacy of EMR in our unit. PATIENTS AND METHODS: A review of a prospective database over a 3-year period identified 87 patients who underwent endoscopic polypectomy for polyps in sizes from 10 to 50 mm, performed by two experienced endoscopists. A total of 33 EMRs were performed on 30 lesions in 24 of these patients. RESULTS: Median size of lesions was 20 mm. Most were located in the rectum and sigmoid. 22 lesions were resected en-bloc while 8 were resected piecemeal. Histologically these lesions were predominantly adenomatous polyps. An incidental focus of adenocarcinoma was found in 7 lesions. Histologically complete excision was achieved in 10 lesions. Although histological completeness of excision was not confirmed in 19 lesions, repeat colonoscopy confirmed successful excision. Only one lesion was incompletely excised requiring surgical resection. Bleeding occurred during 2 EMRs, both times successfully controlled by further injection of adrenaline locally. There was no case of bowel perforation. Further surveillance colonoscopy was performed according to established guidelines. Median follow-up period was 21 months. None of the patients diagnosed with adenocarcinoma showed any evidence of recurrence. CONCLUSION: Within our unit endoscopic mucosal resection appeared to be safe and effective procedure for resecting large colorectal polyps not suitable for conventional polypectomy. This data would support prompt referral of lesions fulfilling these criteria to specialist units offering this service to avoid unnecessary surgery.

Sacral nerve stimulation for faecal incontinence in the UK.

BACKGROUND: Sacral nerve stimulation (SNS) is an effective therapy for faecal incontinence. Published studies derive largely from single centres and there is a need to determine the broader applicability of this procedure. METHODS: Prospective data were collected for all patients undergoing SNS in the UK. Records were reviewed to determine the outcome of treatment. RESULTS: In three UK centres 59 patients underwent peripheral nerve evaluation, with 46 (78 per cent) proceeding to permanent implantation. Of these 46 patients (40 women) all but two had improved continence at a median of 12 (range 1-72) months. Faecal incontinence improved from a median (range) of 7.5 (1-78) to 1 (0-39) episodes per week (P < 0.001). Urgency improved in all but five of 39 patients in whom ability to defer defaecation was determined, improving from a median of 1 (range 0-5) to 10 (range from 1 to more than 15) min (P < 0.001). Maximum anal squeeze pressure and sensory function to rectal distension changed significantly. Significant improvement occurred in general health (P = 0.024), mental health (P = 0.008), emotional role (P = 0.034), social function (P = 0.013) and vitality (P = 0.009) subscales of the Short Form 36 health survey questionnaire. There were no major complications. One implant was removed. CONCLUSION: SNS is a safe and effective treatment, in the medium to long term, for faecal incontinence when conservative treatment has failed.

Neural network analysis of anal sphincter repair.

PURPOSE: Prediction of success after anterior sphincter repair for incontinence is difficult. Standard multivariate analysis techniques have only 75 to 80 percent accuracy. Artificial intelligence, including artificial neural networks, has been used in the analysis of complex clinical data and has proved to be successful in predicting the outcome of other surgical procedures. Using a neural network algorithm, we have assessed the probability of success after anterior sphincter repair. METHODS: Prospective anorectal physiology data of 72 patients undergoing anterior sphincter repair was collected between 1995 and 1999. Complete data sets of 75 percent of the series were used to train an artificial neural network; the remaining 25 percent were used for data validation. The output was continence grading, ranging from 0 to 4 (worse to continent). RESULTS: The outcome at 3, 6, and 12 months postoperatively was obtained and assessed. The best correlation between actual data value and artificial neural network value was found at 12 months (r = 0.931; P = 0.0001). Clear correlations also were found at three months (r = 0.898; P = 0.0001) and six months (r = 0.742; P = 0.002). Results of applying a net to details excluding pudendal nerve latency were poor. CONCLUSIONS: Artificial neural networks are more accurate (93 percent correlation) than standard statistics (75 percent) when applied to the prediction of outcome after anterior sphincter repair. This assessment also confirms the usefulness of pudendal latency in the prediction of anterior sphincter repair outcome. The results obtained highlight the obvious usefulness of artificial neural networks, which could now be used in a prospective evaluation for application of the technique.

Hyperbaric oxygen in the treatment of fecal incontinence secondary to pudendal neuropathy.

PURPOSE: Hyperbaric oxygen therapy has several physiologic effects on damaged nerves in animal models, which lead to an improvement in neurologic function. Idiopathic fecal incontinence secondary to pudendal neuropathy is usually treated with biofeedback, which shows improvement in only 50 percent of patients. METHODS: Thirteen patients (12 females, age range, 40-75 years) with chronic pudendal neuropathy and fecal incontinence were identified. They received 30 treatments of hyperbaric oxygen during a period of 6 weeks. Each treatment was at 2.4 atmospheres breathing pure oxygen for 90 minutes. Pudendal latencies were performed sequentially throughout the treatment and one and six months after it had finished. Questionnaires were used to assess improvements in symptoms and quality of life (Wexner fecal incontinence quality of life score). RESULTS: All patients completed the treatment without major complications. There was a consistent improvement of the latencies (on the left 2.36 msec initially, reduced to 2.08 msec at 6-month follow-up and on the right 2.23 msec, on the left reduced to 2.07 msec at 6 months). These improvements were significant (Wilcoxon's two-tailed, asymptomatic significance, comparing pretreatment to 6-month follow-up, left 0.005, right 0.003). Incontinence sores also improved (12.08 initially to 11.64 at the end of treatment, 10.55 at 1-month follow-up, and 10.45 at 6-month follow-up). Using the same test, the improvement in incontinence scores also was significant when comparing pre-end (0.05) and pre-one month (0.011) but not pre-six month (0.054). CONCLUSIONS: Hyperbaric oxygen therapy has improved pudendal nerve function and continence in this group of patients. The cause for this improvement in latencies is unclear at present but may be because of a direct effect on the nerve or an improvement in blood flow to the nerve through angiogenesis. However, these results are good enough to schedule further trials.