Randomized controlled trial of topical phenylephrine in the treatment of faecal incontinence

Effect of reboxetine and citalopram on anal opening pressure in healthy women: A randomized, double-blind, placebo-controlled crossover study

BACKGROUND

In placebo-controlled clinical trials, reboxetine, a selective noradrenaline reuptake inhibitor, increases urethral pressure and relieves stress urinary incontinence symptoms in women. Considering the close connection in neural regulation of the external urethral and anal sphincters, we hypothesized that reboxetine may also enhance anal sphincter pressure. Conversely, it is believed that selective serotonin reuptake inhibitors may contribute to fecal incontinence by reducing anal sphincter pressure. In this study, we investigated the effect of reboxetine and citalopram on anal opening pressure in healthy female volunteers.

METHODS

In a double-blind, three-way crossover trial, 24 female participants received single doses of 40 mg citalopram, 8 mg reboxetine, and matching placebos, with a minimum of 8-day washout between sessions. Using anal acoustic reflectometry, we measured anal opening pressure during both resting and squeezing conditions at the estimated time of peak plasma concentration for both study drugs.

KEY RESULTS

Compared with placebo, reboxetine increased anal opening pressure with 23.4 cmH2O (95% confidence interval [CI] 16.5-30.2, p < 0.001) during rest and with 22.5 cmH2O (95% CI 15.2-29.8, p < 0.001) during squeeze. Citalopram did not change anal opening pressure statistically significantly compared to placebo.

CONCLUSIONS & INFERENCES

An 8-mg dose of reboxetine increased anal opening pressure substantially in healthy women, suggesting potential benefits for fecal incontinence symptoms. In contrast, a 40-mg dose of citalopram showed a marginal and statistically insignificant effect on anal opening pressure, indicating that selective serotonin reuptake inhibitors do not contribute to fecal incontinence by reducing anal sphincter tone.

Guideline for the diagnosis and treatment of Faecal Incontinence-A UEG/ESCP/ESNM/ESPCG collaboration

INTRODUCTION

The goal of this project was to create an up-to-date joint European clinical practice guideline for the diagnosis and treatment of faecal incontinence (FI), using the best available evidence. These guidelines are intended to help guide all medical professionals treating adult patients with FI (e.g., general practitioners, surgeons, gastroenterologists, other healthcare workers) and any patients who are interested in information regarding the diagnosis and management of FI.

METHODS

These guidelines have been created in cooperation with members from the United European Gastroenterology (UEG), European Society of Coloproctology (ESCP), European Society of Neurogastroenterology and Motility (ESNM) and the European Society for Primary Care Gastroenterology (ESPCG). These members made up the guideline development group (GDG). Additionally, a patient advisory board (PAB) was created to reflect and comment on the draft guidelines from a patient perspective. Relevant review questions were established by the GDG along with a set of outcomes most important for decision making. A systematic literature search was performed using these review questions and outcomes as a framework. For each predefined review question, the study or studies with the highest level of study design were included. If evidence of a higher-level study design was available, no lower level of evidence was sought or included. Data from the studies were extracted by two reviewers for each predefined important outcome within each review question. Where possible, forest plots were created. After summarising the results for each review question, a systematic quality assessment using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) approach was performed. For each review question, we assessed the quality of evidence for every predetermined important outcome. After evidence review and quality assessment were completed, recommendations could be formulated. The wording used for each recommendation was dependent on the level of quality of evidence. Lower levels of evidence resulted in weaker recommendations and higher levels of evidence resulted in stronger recommendations. Recommendations were discussed within the GDG to reach consensus.

RESULTS

These guidelines contain 45 recommendations on the classification, diagnosis and management of FI in adult patients.

CONCLUSION

These multidisciplinary European guidelines provide an up-to-date comprehensive evidence-based framework with recommendations on the diagnosis and management of adult patients who suffer from FI.

A systematic review and network meta-analysis comparing treatments for faecal incontinence

BACKGROUND

Although numerous treatments exist for fecal incontinence (FI), no consensus exists on the best treatment strategy. The aim was to review the literature and to compare the clinical outcomes and effectiveness of treatments available for FI.

MATERIALS AND METHOD

A systematic literature review was performed, from inception to May 2018, of the following databases: MEDLINE, EMBASE, Science Citation Index Expanded, Cochrane Library. The search terms used were "faecal incontinence" and "treatment". Only randomized controlled trials (RCTs) comparing treatments for FI were considered. A Bayesian network meta-analysis was performed using the Markov chain Monte Carlo method.

RESULT

Forty-seven RCTs were included comparing 37 treatments and reporting on 3748 participants. No treatment ranked best or worst with high probability for any outcome of interest. No significant difference was identified between treatments for frequency of FI per week, or in changing the resting pressure, maximum resting pressure, squeeze pressure, and maximum squeeze pressure. Radiofrequency resulted in more adverse events compared to placebo. Sacral nerve stimulation (SNS) and zinc-aluminium improved the fecal incontinence quality of life questionnaire (FIQL) lifestyle, coping, and embarrassment domains compared to placebo. Transcutaneous posterior tibial nerve stimulation (TPTNS) improved the FIQL embarrassment domain compared to placebo. Autologous myoblasts and zinc-aluminium improved the FIQL depression domain compared to placebo. SNS, artificial bowel sphincter (ABS), and zinc-aluminium significantly improved incontinence scores compared to placebo. Injection of non-animal stabilized hyaluronic acid/dextranomer (NASHA/Dx) resulted in more patients with ≥50% reduction in FI episodes compared to placebo.

CONCLUSION

SNS, ABS, TPTNS, NASHA/Dx, zinc-aluminium, and autologous myoblasts resulted in isolated improvements in specific outcomes of interest. No difference was identified in incontinence episodes, no treatment ranked best persistently or persistently improved outcomes, and many included treatments did not significantly benefit patients compared to placebo. Large multicentre RCTs with long-term follow-up and standardized inclusion criteria and outcome measures are needed.

A systematic review of the literature reporting on randomised controlled trials comparing treatments for faecal incontinence in adults

AIM

To perform a review of the literature reporting on randomised controlled trials (RCTs) comparing treatments for faecal incontinence (FI) in adults.

METHODS

A literature search of MEDLINE, Embase, Science Citation Index Expanded and Cochrane was performed in order to identify RCTs reporting on treatments for FI.

RESULTS

The review included 60 RCTs reporting on 4838 patients with a mean age ranging from 36.8 to 88 years. From the included RCTs, 32 did not identify a significant difference between the treatments compared. Contradictory results were identified in RCTs comparing percutaneous posterior tibial nerve stimulation and transcutaneous tibial nerve stimulation versus sham stimulation, biofeedback-pelvic floor muscle training (BF-PFMT) versus PFMT, and between bulking agents such as PTQ^TM versus Durasphere^®. In two separate RCTs, combination treatment of amplitude-modulated medium frequency stimulation and electromyography-biofeedback (EMG-BF), was noted to be superior to EMG-BF and low-frequency electrical stimulation alone. Combination of non-surgical treatments such as BF with sphincteroplasty significantly improved continence scores compared to sphincteroplasty alone. Surgical treatments were associated with higher rates of serious adverse events compared to non-surgical interventions.

CONCLUSIONS

The current evidence has not identified significant differences between treatments for FI, and where differences were identified, the results were contradictory between RCTs.

Libertas: a phase II placebo-controlled study of NRL001 in patients with faecal incontinence showed an unexpected and sustained placebo response

PURPOSE

Faecal incontinence (FI) is distressing, significantly reduces quality of life (QoL) and has few pharmacological treatments. The α1-adrenoceptor agonist NRL001 (1R,2S-methoxamine hydrochloride) improves anal sphincter tone. NRL001 efficacy was evaluated by changes in Wexner scores at week 4 vs. baseline in NRL001-treated patients compared with placebo. Impact of NRL001 on QoL and safety were also assessed.

METHODS

Four hundred sixty-six patients received NRL001 (5, 7.5 or 10 mg) or placebo as suppository, once daily over 8 weeks. Wexner score, Vaizey score and QoL were analysed at baseline, week 4 and week 8. FI episodes and adverse events were recorded in diaries.

RESULTS

At week 4, mean reductions in Wexner scores were -3.0, -2.6, -2.6 and -2.4 for NRL001 5, 7.5, 10 mg and placebo, respectively. All reduced further by week 8. As placebo responses also improved, there was no significant treatment effect at week 4 (p = 0.6867) or week 8 (p = 0.5005). FI episode frequency improved for all patients, but not significantly compared with placebo (week 4: p = 0.2619, week 8: p = 0.5278). All patients' QoL improved, but not significantly for all parameters (p > 0.05) except depression/self-perception at week 4 (p = 0.0102) and week 8 (p = 0.0069), compared with placebo. Most adverse events were mild and judged probably or possibly related to NRL001.

CONCLUSIONS

All groups demonstrated improvement in efficacy and QoL compared with baseline. NRL001 was well-tolerated without serious safety concerns. Despite the improvement in all groups, there was no statistically significant treatment effect, underlining the importance of relating results to a placebo arm.

[Management of postpartum anal incontinence: A systematic review]

AIM

To analyse the prevalence of postpartum anal incontinence, its risk factors, and its management.

MATERIALS AND METHODS

A comprehensive systematic review of the literature on PubMed, Medline, Embase and Cochrane using: postpartum anal incontinence, postpartum fecal incontinence, perineal rehabilitation, anal surgery.

RESULTS

The prevalence of postpartum anal incontinence varied from 4% (primipare) to 39% (multipare) at 6 weeks postpartum, whereas fecal incontinence can reach respectively 8 to 12% 6 years after delivery. Identified risk factors were: vaginal delivery (OR: 1.32 [95%CI: 1.04-1.68]) compared to cesarean section, instrumental extractions (OR: 1.47 [95%CI: 1.22-1.78]) compared to spontaneous vaginal delivery but it was only with forceps (OR: 1.50 [95%CI: 1.19-1.89]) and not with vaccum (OR: 1.31 [95%CI: 0.97-1.77]). Maternal age over 35 years (OR: 6 [95%CI: 1.85-19.45]), number of births (3 births: OR: 2.91 [95%CI: 1.32-6.41]) and the occurrence of anal-sphincter injury (OR: 2.3 [95%CI: 1.1-5]) were associated with an increased risk of anal incontinence regardless of the type of delivery compared to a group of women without anal incontinence. Perineal rehabilitation should be interpreted with caution because of the lack of randomized controlled trials. A reassessment at 6 months postpartum in order to propose a surgical treatment by sphincteroplasty could be considered if symptoms persist. The results of the sphincteroplasty were satisfactory but with a success rate fading in time (60 to 90% at 6 months against 50 to 40% at 5 and 10 years).

CONCLUSION

Postpartum anal incontinence requires special care. Recommendations for the management of postpartum anal incontinence would be useful.

Use of hollow microneedles for targeted delivery of phenylephrine to treat fecal incontinence

A hollow microneedle (HM) was prepared to deliver a phenylephrine (PE) solution into the anal sphincter muscle as a method for treating fecal incontinence. The goal of this study was the local targeted delivery of PE into the sphincter muscle through the perianal skin with minimal pain using hollow microneedles, resulting in the increase of resting anal sphincter pressure. PE was administered on the left and the right sides of the anus of a rat through the perianal skin using 1.5mm long HM. An in vivo imaging system study was conducted after injection of Rhodamine B, and a histological study was performed after injection of gentian violet. The resting anal sphincter pressure in response to various drug doses was measured by using an air-charged catheter. Anal pressure change produced by HM administration was compared with change produced by intravenous injection (IV), subcutaneous (SC) injection and intramuscular (IM) injection. The change in mean blood pressure produced by HM administration as a function of PE dose was compared with change produced by PBS injection. A pharmacokinetic study of the new HM administration method was performed. A model drug solution was localized in the muscle layer under the perianal skin at the injection site and then diffused out over time. HM administration of PE induced significant contraction of internal anal sphincter pressure over 12h after injection, and the maximum anal pressure was obtained between 5 and 6h. Compared to IV, SC and IM treatments, HM treatment produced greater anal pressure. There was no increase in blood pressure after HM administration of PE within the range of predetermined concentration. Administration of 800μg/kg of PE using HM produced 0.81±0.38h of tmax. Our study suggests that HM administration enables local delivery of a therapeutic dose of PE to the anal sphincter muscle layer with less pain. This new treatment has great potential as a clinical application because of the ease of the procedure, minimal pain, and dose-dependent response.

Management of pelvic floor disorders: biofeedback and more

OPINION STATEMENT

Defecatory disorders (DD) and fecal incontinence (FI) are common conditions. DD are primarily attributable to impaired rectoanal function during defecation or structural defects. FI is caused by one or more disturbances of anorectal continence mechanisms. Altered stool consistency may be the primary cause or may unmask anorectal deficits in both conditions. Diagnosis and management requires a systematic approach beginning with a thorough clinical assessment. Symptoms do not reliably differentiate a DD from other causes of constipation such as slow or normal transit constipation. Therefore, all constipated patients who do not adequately respond to medical therapy should be considered for anorectal testing to identify a DD. Preferably, two tests indicating impaired defecation are required to diagnose a DD. Patients with DD, or those for whom testing is not available and the clinical suspicion is high, should be referred for biofeedback-based pelvic floor physical therapy. Patients with FI should be managed with lifestyle modifications, pharmacotherapy for bowel disturbances, and management of local anorectal problems (e.g., hemorrhoids). When these measures are not beneficial, anorectal testing and pelvic floor retraining with biofeedback therapy should be considered. Sacral nerve stimulation or perianal bulking could be considered in patients who have persistent symptoms despite optimal management of bowel disturbances and pelvic floor retraining.

Medical management of fecal incontinence in challenging populations: a review

Fecal incontinence (FI) is a common and growing problem in the United States. Although there are multiple emerging novel interventions for the treatment of FI, the mainstay of initial therapy remains medical management. In this article, we review the available literature on the medical management of FI, with a special focus on patients with multiple sclerosis, diabetes mellitus, and the elderly.

Libertas: rationale and study design of a multicentre, Phase II, double-blind, randomised, placebo-controlled investigation to evaluate the efficacy, safety and tolerability of locally applied NRL001 in patients with faecal incontinence

AIMS

Faecal incontinence affects up to 8% of adults. Associated social isolation and subsequent depression can have devastating effects on quality of life (QoL). Faecal incontinence is an underreported health problem as the social isolation and stigma that patients experience makes it difficult for sufferers to discuss their condition with a physician. There have been few well-designed, placebo-controlled clinical trials of treatment for faecal incontinence and little clinical evidence is available to inform the most appropriate management strategies. Libertas, a robustly designed study will investigate the efficacy and safety of NRL001 (1R,2S-methoxamine), an α1 -adrenoceptor agonist, in the treatment of faecal incontinence.

METHODS

Libertas is a multicentre, Phase II, double-blind, randomised, placebo-controlled, parallel group study. Patient recruitment took place across 55 study centres in Europe. Patients suffering with faecal incontinence were randomised into four groups (approximately 110 each) to receive once daily self-administered doses of NRL001 (5, 7.5 or 10 mg or placebo in a suppository formulation) for 8 weeks. The primary objective of Libertas is to assess the impact of once daily administration of NRL001 on the severity and frequency of incontinence episodes as assessed by the Wexner score at 4 weeks, compared with placebo. Secondary outcomes include measures of efficacy of NRL001 compared with placebo following 8 weeks treatment; safety and tolerability; evaluation of plasma pharmacokinetics; establishment of any pharmacokinetic/pharmacodynamic relationship to adverse events; dose-response relationship; the efficacy of NRL001 therapy at 4 and 8 weeks assessed by the Vaizey score; and QoL using the Faecal Incontinence Quality of Life and the EQ-5D-5L Healthcare Questionnaires following 4 and 8 weeks NRL001 therapy. Overall patient satisfaction with the treatment will also be evaluated.

DISCUSSION

This is the first randomised controlled study to investigate the efficacy and safety of a selective α1 -adrenoceptor agonist for the treatment of faecal incontinence. Furthermore, this is the first time the impact of NRL001 on assessments of QoL, health outcomes and patient satisfaction will be assessed. Innovative strategies were developed to meet the challenge of recruiting patients for this study, for example, media advertising, posters and mailshots as allowed by each study centre.

A randomised, controlled, crossover study to investigate the safety and response of 1R,2S-methoxamine hydrochloride (NRL001) on anal function in healthy volunteers

AIMS

This study aimed to assess the dose and volume effects of suppository preparations and safety of NRL001 (one of four possible stereoisomers of methoxamine hydrochloride) on anal sphincter tone using rectal suppositories in healthy adult volunteers.

METHODS

This was a Phase I, single-centre, randomised, double-blind, three-way crossover study during which subjects received three single doses of 1 g rectal suppositories (containing 5 or 10 mg NRL001 or matching placebo) or 2 g rectal suppositories (containing 10 or 15 mg NRL001 or matching placebo) on three separate dosing days. The outcome measures were mean anal resting pressure (MARP) variables (monitored continuously for 20-30 min before and up to 6 h after dosing), pharmacokinetics (PK) and safety assessments.

RESULTS

Twenty-six subjects were dosed with study medication. Two subjects were withdrawn prematurely and were not included in the main analysis. There was a dose-dependent increase in anal sphincter tone (MARP) when comparing the 5 and 10 mg doses of NRL001; however, the 15 mg dose did not have a significantly greater effect than the 10 mg dose. Suppository size (1 or 2 g) did not appear to have an effect on sphincter tone. There was no evidence against dose proportionality for the PK variables, but the mean maximum plasma concentration (Cmax ) for the 1 g suppository group was higher than for the 2 g group. Twenty-one adverse events were reported in 8 (30.8%) subjects. A dose dependent decrease in heart rate was noted; however, there were no adverse events reported that were related to this reduction in heart rate.

CONCLUSIONS

The increase in anal sphincter tone supports the potential therapeutic use of NRL001 in treating faecal incontinence, with further studies in patients required. NRL001 was well tolerated in single doses of up to 15 mg.

A double-blind, placebo-controlled, randomised, parallel-group, dose-escalating, repeat dose study in healthy volunteers to evaluate the safety, tolerability, pharmacodynamic effects and pharmacokinetics of the once daily rectal application of NRL001 suppositories for 14 days

AIMS

The 1R,2S stereoisomer of methoxamine hydrochloride, NRL001, is a highly selective α1-adrenoceptor agonist being developed for the local treatment of non-structural faecal incontinence caused by weak internal anal sphincter tone. This study investigated the steady state pharmacokinetics (PK) and safety of 2 g rectal suppositories containing NRL001 in different strengths (7.5, 10, 12.5 or 15 mg).

METHODS

Healthy volunteers aged 18-45 years received 14 daily doses of NRL001 2 g suppositories or matching placebo. In each dose group nine participants received NRL001 and three received placebo. Blood samples to determine NRL001 concentrations were taken on Days 1, 7 and 14. Cardiovascular parameters were collected via electrocardiograms, Holter monitoring (three lead Holter monitor) and vital signs.

RESULTS

Forty-eight volunteers were enrolled; 43 completed the study and were included in the PK analysis population. AUC and Cmax broadly increased with increasing dose, Tmax generally occurred between 4.0 and 5.0 h. Although the data did not appear strongly dose proportional, dose proportionality analysis did not provide evidence against dose proportionality as the log(dose) coefficients were not significantly < 1. NRL001 did not accumulate over time for any dose. Increasing NRL001 concentrations were related to changes in vital sign variables, most notably decreased heart rate. The most commonly reported adverse events (AEs) in the active treatment groups were paraesthesia and piloerection.

CONCLUSIONS

Treatment with NRL001 was generally well tolerated over 14 days once daily dosing and plasma NRL001 did not accumulate over time. Treatment was associated with changes in vital sign variables, most notably decreased heart rate. AEs commonly reported with NRL001 treatment were events indicative of a systemic α-adrenergic effect.

Argon plasma coagulation therapy versus topical formalin for intractable rectal bleeding and anorectal dysfunction after radiation therapy for prostate carcinoma

PURPOSE

To evaluate and compare the effect of argon plasma coagulation (APC) and topical formalin for intractable rectal bleeding and anorectal dysfunction associated with chronic radiation proctitis.

METHODS AND MATERIALS

Thirty men (median age, 72 years; range, 49-87 years) with intractable rectal bleeding (defined as ≥1× per week and/or requiring blood transfusions) after radiation therapy for prostate carcinoma were randomized to treatment with APC (n=17) or topical formalin (n=13). Each patient underwent evaluations of (1) anorectal symptoms (validated questionnaires, including modified Late Effects in Normal Tissues-Subjective, Objective, Management, and Analytic and visual analogue scales for rectal bleeding); (2) anorectal motor and sensory function (manometry and graded rectal balloon distension); and (3) anal sphincteric morphology (endoanal ultrasound) before and after the treatment endpoint (defined as reduction in rectal bleeding to 1× per month or better, reduction in visual analogue scales to ≤25 mm, and no longer needing blood transfusions).

RESULTS

The treatment endpoint was achieved in 94% of the APC group and 100% of the topical formalin group after a median (range) of 2 (1-5) sessions of either treatment. After a follow-up duration of 111 (29-170) months, only 1 patient in each group needed further treatment. Reductions in rectal compliance and volumes of sensory perception occurred after APC, but no effect on anorectal symptoms other than rectal bleeding was observed. There were no differences between APC and topical formalin for anorectal symptoms and function, nor for anal sphincteric morphology.

CONCLUSIONS

Argon plasma coagulation and topical formalin had comparable efficacy in the durable control of rectal bleeding associated with chronic radiation proctitis but had no beneficial effect on anorectal dysfunction.

Review of organic causes of fecal incontinence in children: evaluation and treatment

Even though fecal incontinence (FI) in children is most commonly the result of functional constipation, there are organic conditions that can be associated with incontinence. FI has a major impact on the quality of life of those children who experience it. The general objectives of any bowel program are to achieve predictability and independence. This is achieved by manipulating colonic transit and stool consistency and by producing more controlled evacuations, usually with the use of rectal interventions. Dietary interventions and medications can be used to change stool consistency or to manipulate transit by accelerating or slowing it down. Biofeedback or other interventions that increase sphincter pressure can also be used to improve anorectal function. Enemas or suppositories can be used to empty the sigmoid colon in a more controlled manner. With the recent advent of the antegrade colonic enemas, the patient can have predictable bowel movements and become independent.

Drug treatment for faecal incontinence in adults

BACKGROUND

Faecal incontinence (leakage of bowel motions or stool) is a common symptom which causes significant distress and reduces quality of life.

OBJECTIVES

To assess the effects of drug therapy for the treatment of faecal incontinence. In particular, to assess the effects of individual drugs relative to placebo or other drugs, and to compare drug therapy with other treatment modalities.

SEARCH METHODS

We searched the Cochrane Incontinence Group Specialised Register of Trials, which contains trials identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and MEDLINE in process, and handsearching of journals and conference proceedings (searched 21 June 2012) and the reference lists of relevant articles.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials were included in this systematic review.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened abstracts, extracted data and assessed risk of bias of the included trials.

MAIN RESULTS

Sixteen trials were identified, including 558 participants. Eleven trials were of cross-over design. Eleven trials included only people with faecal incontinence related to liquid stool (either chronic diarrhoea, following ileoanal pouch or rectal surgery, or due to use of a weight-reducing drug). Two trials were amongst people with weak anal sphincters, one in participants with faecal impaction and bypass leakage, and one in geriatric patients. In one trial there was no specific cause for faecal incontinence.Seven trials tested anti-diarrhoeal drugs to reduce faecal incontinence and other bowel symptoms (loperamide, diphenoxylate plus atropine, and codeine). Six trials tested drugs that enhance anal sphincter function (phenylepinephrine gel and sodium valproate). Two trials evaluated osmotic laxatives (lactulose) for the treatment of faecal incontinence associated with constipation in geriatric patients. One trial assessed the use of zinc-aluminium ointment for faecal incontinence. No studies comparing drugs with other treatment modalities were identified.There was limited evidence that antidiarrhoeal drugs and drugs that enhance anal sphincter tone may reduce faecal incontinence in patients with liquid stools. Loperamide was associated with more adverse effects (such as constipation, abdominal pain, diarrhoea, headache and nausea) than placebo. However, the dose may be titrated to the patient's symptoms to minimise side effects while achieving continence. The drugs acting on the sphincter sometimes resulted in local dermatitis, abdominal pain or nausea. Laxative use in geriatric patients reduced faecal soiling and the need for help from nurses.Zinc-aluminium ointment was associated with improved quality of life, with no reported adverse effects. However, the observed improvement in quality of life was seen in the placebo group as well as the treatment group.It should be noted that all the included trials in this review had small sample sizes and short duration of follow-up. 'Risk of bias' assessment was unclear for most of the domains as there was insufficient information. There were no data suitable for meta-analysis.

AUTHORS' CONCLUSIONS

The small number of trials identified for this review assessed several different drugs in a variety of patient populations. The focus of most of the included trials was on the treatment of diarrhoea, rather than faecal incontinence. There is little evidence to guide clinicians in the selection of drug therapies for faecal incontinence. Larger, well-designed controlled trials, which use the recommendations and principles set out in the CONSORT statement, and include clinically important outcome measures, are required.

[Pelvic floor and anal incontinence. Conservative therapy]

Conservative treatment of fecal incontinence and obstructive defecation can be treated by many conservative treatment modalities. This article presents the options of medication therapy, spincter exercises, electric stimulation, transcutaneous tibial nerve stimulation, anal irrigation and injection of bulking agents. These methods are presented with reference to the currently available literature but the evidence-based data level for all methods is low. For minor disorders of anorectal function these conservative methods can lead to an improvement of anorectal function and should be individually adapted.

New treatment for faecal incontinence using zinc-aluminium ointment: a double-blind randomized trial

AIM

In a randomized double-blind study the therapeutic effect of a novel zinc-aluminium ointment was compared with placebo in patients with faecal incontinence.

METHOD

A randomized double-blind trial was performed. Patients who met the inclusion criteria were randomized to receive the ointment or a placebo. All were evaluated prior to and 3 weeks after ointment application, using the Wexner incontinence score and the Fecal Incontinence Quality of Life (FIQL) score.

RESULTS

Fifty patients were randomized and six were lost to follow-up, leaving 24 in the treatment and 20 in the placebo group. The average ages were 61.3 and 60.7 years. The respective Wexner scores prior to intervention were 16.6 and 16.7. They decreased significantly after treatment to 8.5 and 13.1 (P<0.001 and P=0.002 respectively). There was a significant difference in the final scores, favouring the treatment group (P=0.001). The FIQL scores for the treatment group were also significantly better in all parameters compared with those of the placebo group.

CONCLUSION

The study shows that the zinc-aluminium based ointment decreases faecal incontinence significantly compared with placebo.

The efficacy and safety of PSD503 (phenylephrine 20%, w/w) for topical application in women with stress urinary incontinence. A phase II, multicentre, double-blind, placebo controlled, 2-way cross over study

OBJECTIVE

PSD503 is a topical gel containing phenylephrine 20% weight/weight (w/w) intended for vaginal application close to the area of the urethral sphincter in women with SUI and has been used in patients with faecal incontinence. The primary objective of this proof of concept study was to evaluate the efficacy of PSD503 in women with SUI as measured by the change in pad weight following an exercise stress pad test. The secondary objectives were to evaluate plasma concentrations of PSD503, BP changes and pulse rate over 3h following administration and to assess safety and tolerability.

STUDY DESIGN

This was a phase II multi-centre, double-blind, placebo-controlled, 2 way cross-over study. Women were assessed objectively pre and post PSD503 administration using a standardised exercise stress pad test. Safety was assessed by monitoring pulse, BP and plasma levels of PSD503 over 3h following administration. A power calculation suggested a >80% power to demonstrate (at the 5% level of significance) a difference between treatments of 10-20g with a sample size of 30 patients.

RESULTS

14 patients were screened and 12 patients randomised over 20 months. Projections indicated the study would not attain its full quota within 1 year and it was terminated early. Treatment with PSD503 resulted in a greater reduction in pad weight gain than placebo, when expressed as both a percentage change (median % change: placebo - 38.00%, PSD503 - 54.33%) and absolute change (median absolute change: placebo - 10.0g, 20% (w/w) PSD503 - 22.0g) from pre-dose leakage. PSD503 was absorbed into the blood within 1h (median concentration 1.490ng/ml). Plasma concentrations at 3h (median 1.305ng/ml) were less than that at 1h and lower than plasma concentrations seen following phenylephrine-containing cold remedies. There were no withdrawals, serious adverse events and it was well tolerated overall.

CONCLUSION

This is the first proof of concept study to demonstrate that a topical α adrenergic agonist gel is rapidly and consistently absorbed vaginally and may have a role in the management of female SUI. However, since recruitment was difficult this may indicate that whilst objectively effective, acceptability in clinical practice may be poor.

Local transdermal delivery of phenylephrine to the anal sphincter muscle using microneedles

We propose pretreatment using microneedles to increase perianal skin permeability for locally targeted delivery of phenylephrine (PE), a drug that increases resting anal sphincter pressure to treat fecal incontinence. Microneedle patches were fabricated by micromolding poly-lactic-acid. Pre-treatment of human cadaver skin with microneedles increased PE delivery across the skin by up to 10-fold in vitro. In vivo delivery was assessed in rats receiving treatment with or without use of microneedles and with or without PE. Resting anal sphincter pressure was then measured over time using water-perfused anorectal manometry. For rats pretreated with microneedles, topical application of 30% PE gel rapidly increased the mean resting anal sphincter pressure from 7±2 cm H(2)O to a peak value of 43±17 cm H(2)O after 1 h, which was significantly greater than rats receiving PE gel without microneedle pretreatment. Additional safety studies showed that topically applied green fluorescent protein-expressing E. coli penetrated skin pierced with 23- and 26-gauge hypodermic needles, but E. coli was not detected in skin pretreated with microneedles, which suggests that microneedle-treated skin may not be especially susceptible to infection. In conclusion, this study demonstrates local transdermal delivery of PE to the anal sphincter muscle using microneedles, which may provide a novel treatment for fecal incontinence.

Investigation of the distribution and function of alpha-adrenoceptors in the sheep isolated internal anal sphincter

BACKGROUND AND PURPOSE

We have investigated the distribution of alpha-adrenoceptors in sheep internal anal sphincter (IAS), as a model for the human tissue, and evaluated various imidazoline derivatives for potential treatment of faecal incontinence.

EXPERIMENTAL APPROACH

Saturation and competition binding with (3)H-prazosin and (3)H-RX821002 were used to confirm the presence and density of alpha-adrenoceptors in sheep IAS, and the affinity of imidazoline compounds at these receptors. A combination of in vitro receptor autoradiography and immunohistochemistry was used to investigate the regional distribution of binding sites. Contractile activity of imidazoline-based compounds on sheep IAS was assessed by isometric tension recording.

KEY RESULTS

Saturation binding confirmed the presence of both alpha(1)- and alpha(2)-adrenoceptors, and subsequent characterization with sub-type-selective agents, identified them as alpha(1A)- and alpha(2D)-adrenoceptor sub-types. Autoradiographic studies with (3)H-prazosin showed a positive association of alpha(1)-adrenoceptors with immunohistochemically identified smooth muscle fibres. Anti-alpha(1)-adrenoceptor immunohistochemistry revealed similar distributions of the receptor in sheep and human IAS. The imidazoline compounds caused concentration-dependent contractions of the anal sphincter, but the maximum responses were less than those elicited by l-erythro-methoxamine, a standard non-imidazoline alpha(1)-adrenoceptor agonist. Prazosin (selective alpha(1)-adrenoceptor antagonist) significantly reduced the magnitude of contraction to l-erythro-methoxamine at the highest concentration used. Both prazosin and RX811059 (a selective alpha(2)-adrenoceptor antagonist) reduced the potency (pEC(50)) of clonidine.

CONCLUSIONS AND IMPLICATIONS

This study shows that both alpha(1)- and alpha(2)-adrenoceptors are expressed in the sheep IAS, and contribute (perhaps synergistically) to contractions elicited by various imidazoline derivatives. These agents may prove useful in the treatment of faecal incontinence.

Nonoperative management of fecal incontinence

Fecal incontinence is a significant health problem that affects quality of life. Continence may often be improved with changes in diet with or without pharmacologic treatment to optimize the consistency of stool. Biofeedback is a multifaceted therapeutic approach that helps an individual improve his or her sensitivity to rectal distention and respond with appropriate voluntary sphincter control. One or more of these techniques can be used in conjunction with education and supportive counseling to optimize an individual's continence.

Pharmacology of the internal anal sphincter and its relevance to faecal incontinence

1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non-adrenergic non-cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients' quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence.

Fecal incontinence and biofeedback therapy

Biofeedback as delivered in most clinical settings in Western medicine has been consistently reported to improve symptoms of fecal incontinence. Closer scrutiny of the elements of the intervention and controlled studies, however, have consistently failed to find any benefit of the biofeedback element of this complex package of care; nor has any superiority been found for one modality over another. There is a need for further well-designed and adequately powered randomized controlled trials. Meanwhile, there can be little doubt that conservative interventions improve many patients with fecal incontinence to the point where most report satisfaction with treatment and do not wish to consider more invasive options, such as surgery.

Characterization of the alpha1-adrenoceptor subtype mediating contractions of the pig internal anal sphincter

BACKGROUND AND PURPOSE

The internal anal sphincter has been shown to contract in response to alpha1-adrenoceptor stimulation and therefore alpha1-adrenoceptor agonists may be useful in treating faecal incontinence. This study characterizes the alpha1-adrenoceptor subtype responsible for mediating contraction of the internal anal sphincter of the pig.

EXPERIMENTAL APPROACH

The potency of agonists and the affinities of several receptor subtype selective antagonists were determined on smooth muscle strips for the pig internal anal sphincter. Cumulative concentration-response curves were performed using phenylephrine and noradrenaline.

KEY RESULTS

The potency of the alpha1A-adrenoceptor selective agonist A61603 (pEC50=7.79+/-0.04) was 158-fold greater than that for noradrenaline (pEC50=5.59+/-0.02). Phenylephrine (pEC50=5.99+/-0.05) was 2.5-fold more potent than noradrenaline. The alpha1D-adrenoceptor selective antagonist BMY7378 caused rightward shifts of the concentration-response curves to phenylephrine and noradrenaline, yielding low affinity estimates of 6.59+/-0.15 and 6.33+/-0.13, respectively. Relatively high affinity estimates were obtained for the alpha1A-adrenoceptor selective antagonists, RS100329 (9.01+/-0.14 and 9.06+/-0.22 with phenylephrine and noradrenaline, respectively) and 5-methylurapidil (8.51+/-0.10 and 8.31+/-0.10, respectively). Prazosin antagonized responses of the sphincter to phenylephrine and noradrenaline, yielding mean affinity estimates of 8.58+/-0.10 and 8.15+/-0.08, respectively. The Schild slope for prazosin with phenylephrine was equal to unity (1.01+/-0.24), however the Schild slope using noradrenaline was significantly less than unity (0.50+/-0.11, P<0.05).

CONCLUSION AND IMPLICATIONS

The results suggest that contraction of circular smooth muscle from the pig internal anal sphincter is mediated via a population of adrenoceptors with the pharmacological characteristics of the alpha1A/L-adrenoceptor, most probably the alpha1L-adrenoceptor form of this receptor.

Towards safer treatments for benign anorectal disease: the pharmacological manipulation of the internal anal sphincter

INTRODUCTION

The internal anal sphincter (IAS) is an important structure that is responsible for the majority of resting tone of the sphincter complex. It has a central role in continence and damage to the muscle has serious implications. Injury is most frequently from obstetric trauma though iatrogenic injury from proctological surgery is also common. This review expands on how developments in understanding of the pharmacology of IAS might identify drug treatments as alternatives for proctological conditions such as anal fissure, avoiding the risk of sphincter injury. It also examines the role of pharmacology in treatment of those patients with established incontinence.

RESULTS

Much of the basic physiology and pharmacology of the IAS has been established through in vitro analysis, particularly in the superfusion organ bath. Further analysis has been undertaken using animal models such the pig. Clinical trials have established the efficacy of a number of agents for reducing IAS tone including glyceryl trinitrate and botulinum toxin. These drugs are probably safer, but less effective, than surgery for sphincter spasm, as is seen in anal fissure, though surgery alone or in combination with drug treatment may be appropriate for some patients. In vitro analysis and small-scale clinical trials suggest that phenylephrine and methoxamine may have a role in treating patients with incontinence primarily attributable to inadequate IAS function.

CONCLUSIONS

The pharmacology of IAS has been extensively studied in the laboratory, both in vitro and in animal models. In a short time, this laboratory work has been applied to clinical problems after testing in clinical trials. It is likely, however, that the best drugs and the optimal targets for manipulation have not yet been identified.

The efficacy and adverse effects of topical phenylephrine for anal incontinence after low anterior resection in patients with rectal cancer

BACKGROUND

Anal incontinence is experienced by some patients with rectal cancer who received low anterior resection. This study was to examine the efficacy and adverse effects of the alpha-1 adrenergic agonist phenylephrine, which causes contraction of the internal anal sphincter and raises the resting pressure in these patients.

PATIENTS AND METHODS

Thirty-five patients with anal incontinence were treated with 30% phenylephrine or a placebo randomly allocated in a double-blind study. The efficacy of the drug was assessed by changes in the following standardized questionnaire scores: the fecal incontinence severity index (FISI), fecal incontinence quality of life (FIQL) scales, and a global efficacy question. Anal sphincter function was evaluated using anorectal manometry.

RESULTS

Phenylephrine did not improve either the FISI score or any of the four FIQL scores. Five of 17 (29%) patients reported subjective improvement after phenylephrine compared with 4 of 12 (33%) using the placebo. The maximum resting anal pressure did not differ between baseline and after 4 weeks application of phenylephrine (30.0 to 27.3 mmHg). In the phenylephrine group, allergic dermatitis was developed in five patients and headache in two.

CONCLUSION

In the patients with anal incontinence after low anterior resection for rectal cancer, phenylephrine gel did not seem to be helpful in relieving symptoms with some adverse effects.

Intra-anal application of l-erythro methoxamine gel increases anal resting pressure in patients with incontinence

Background

This study examined the effects of a single dose of intra-anal l-erythro methoxamine on mean anal resting pressure (MARP) and cardiovascular variables in patients with faecal incontinence.

Methods

Patients had anorectal physiology tests and ultrasonography before participating. Six patients received 0·3 and 1 per cent gels on separate days, two patients received 0·3 per cent gel, and two patients received 1 per cent gel. MARP, blood pressure, pulse rate and plasma drug concentrations were measured for 6 h after application.

Results

Intra-anal 0·3 per cent gel caused a rapid, significant rise in MARP lasting 2 h (P = 0·036). In four of these patients, the response was sufficient to increase MARP to within the normal range at 2 h. Application of 1 per cent gel caused a significant rise in MARP for 4 h after application (P = 0·028). There was a significant decrease in pulse at 2 and 1 h respectively after application of 0·3 and 1 per cent gels.

Conclusion

Intra-anal application of l-erythro methoxamine can be used to increase MARP in patients with faecal incontinence. Application of 1 per cent l-erythro methoxamine gel produced a rapid, sustained rise in MARP, which raises the possibility of therapeutic application.

Elastomer implants in faecal incontinence: a blind, randomized placebo-controlled study

AIM

To test efficacy and safety of polydimethylsiloxane elastomer implants, a silicone biomaterial, in patients with severe faecal incontinence related to an impaired internal anal sphincter.

METHODS

Subjects were randomized to receive three injections of 2.5 mL of either physiological saline or polydimethylsiloxane elastomer. After local anaesthesia, an 18 gauge, 2.5-in needle was inserted through the perianal skin and laid down into the intersphincteric space. Treatment (saline or polydimethylsiloxane elastomer) was administered by means of a ratchet gun. Three injections of 2.5 mL each were performed in the area of the internal anal sphincter at 3, 7 and 11 o'clock positions. Main end point was the percentage of subjects in each treatment arm experiencing a successful treatment, defined as a Cleveland Clinic Florida-Faecal Incontinence score <8, 3 months after treatment. Secondary end points were quality of life scores, weekly number of faecal incontinence episodes, subject acceptance and adverse events rate. Both patients and end point assessments were blinded to treatment.

RESULTS

44 women (64.3 +/- 9 years) with a baseline Cleveland Clinic Florida-Faecal Incontinence score > or =8 were enrolled prospectively; 22 received polydimethylsiloxane elastomer and 22 saline treatment. Treatment was well tolerated. At 3 months, the percentage of subjects experiencing a successful treatment was not different between polydimethylsiloxane elastomer and saline groups (23% vs. 27%, respectively, P = 0.73). Moreover, Cleveland Clinic Florida-Faecal Incontinence score was not significantly different between polydimethylsiloxane elastomer and saline groups (11.7 +/- 4.7 vs. 11.4 +/- 4.5, respectively, P = 0.79).

CONCLUSIONS

Polydimethylsiloxane elastomer implants cannot be recommended for treatment of severe faecal incontinence related to impaired internal anal sphincter.

Pharmacotherapy for fecal incontinence: a review

Fecal incontinence is a common clinical problem that often is frustrating to the patient and treating physician. Nonsurgical management for fecal incontinence includes dietary manipulation, Kegel exercises, perianal skin care, and biofeedback therapy. Pharmacotherapies often are used to assist in management of fecal incontinence. A variety of pharmacotherapies have been utilized for the management of fecal incontinence; limited data from randomized, placebo-controlled trials are available. This is a review of the existing literature on clinical trials of several classes of drugs and other medical therapies that may be beneficial for patients with fecal incontinence. The information in this article was obtained by a MEDLINE search for all clinical trials of drug therapy for fecal incontinence. These treatments and the existing data on their use are summarized. Treatments reviewed include stool bulking agents, with an emphasis on the most promising effect obtained with calcium polycarbophil, constipating agents, including loperamide, codeine, amitriptyline, atropine, and diphenoxylate agents injected into the anal sphincter, drugs to enhance anal sphincter function, including topical phenylepherine and oral sodium valproate, and trials of fecal disimpaction. A new classification to easily remember the treatment categories for this condition, based on the "ABCs of treatment for fecal incontinence," has been introduced into the structure of this review.

Pelvic floor: anatomy and function

The pelvic floor is a dome-shaped striated muscular sheet that encloses the bladder, uterus, and rectum, and, together with the anal sphincters, has an important role in regulating storage and evacuation of urine and stool. This article reviews the anatomy, nerve supply, pharmacology, and functions of the anal sphincters and the pelvic floor. The internal and external anal sphincters are primarily responsible for maintaining faecal continence at rest and when continence is threatened, respectively. Defecation is a somato-visceral reflex regulated by dual nerve supply (i.e. somatic and autonomic) to the anorectum. The net effects of sympathetic and cholinergic stimulation are to increase and reduce anal resting pressure, respectively. Faecal incontinence and functional defecatory disorders may result from structural changes and/or functional disturbances in the mechanisms of faecal continence and defecation.

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.

The etiology, assessment, and treatment of fecal incontinence

Fecal incontinence is a common symptom that often impairs quality of life. It is generally caused by a variety of conditions that are associated with anorectal sensorimotor dysfunction and/or diarrhea. Assessment should be tailored to age and symptom severity. Modulation of disordered bowel habits is the key to management; biofeedback and surgery might also be beneficial.

Selecting an outcome measure for evaluating treatment in fecal incontinence

PURPOSE

Various outcome measures exist to evaluate treatment in fecal incontinence, including descriptive, severity (fecal incontinence scoring systems), and impact (quality-of-life questionnaires) and diagnostic measures. We studied associations between changes after treatment for a number of outcome measures and compared them to patients' subjective perception of relief.

METHODS

We analyzed data of 66 patients (92 percent female; mean age, 62 years) (Vaizey score, Wexner score, two impact scales, utility, resting pressure, and maximal incremental squeeze pressure) at baseline and after physiotherapy. In a standardized interview by phone, we asked patients to compare their situation before and after treatment. Correlations between changes in outcome measures were calculated. These changes were compared with patients' subjective perception.

RESULTS

There was a high correlation between the changes in the Vaizey and the Wexner scores (r = 0.94, P < 0.01). Changes in Vaizey and Wexner scores correlated moderately with changes in maximum incremental squeeze pressure (r = -0.29, -0.30, both P < 0.05). Changes in utility and resting pressure were not correlated with changes in any of the other measurements (all r values between -0.086 and 0.18). Average severity scores (Vaizey and Wexner) were 1 point lower for patients who rated their situation as worse or equal (62 percent), 4 points lower for patients who reported their situation to be better (21 percent), and 9 points lower in patients who rated their situation much better (17 percent) (P < .05).

CONCLUSION

Severity measures are best related to patients' subjective perception of relief.

Intra-anal and rectal application of l-erythro methoxamine gel increases anal resting pressure in healthy volunteers

Background

This study examined the effect of a single local application of l-erythro methoxamine, an α1-adrenoceptor agonist, on mean anal resting pressure (MARP) and cardiovascular variables in healthy volunteers.

Methods

l-Erythro methoxamine gel was administered in a single-blind manner; 0·3–3 per cent gels were applied perianally (n = 12), 1–3 per cent gels intra-anally (n = 16) and 1 per cent gel rectally (n = 8). MARP, systolic blood pressure, diastolic blood pressure and pulse rate were measured before application and for up to 6 h afterwards. Blood samples were taken to estimate plasma drug levels.

Results

Perianal gel produced no increase in MARP. Intra-anal 1 per cent and 3 per cent gel produced a significant rapid rise in MARP for 4 and 5 h respectively after application (P = 0·012 and P = 0·017 respectively). Rectal 1 per cent gel increased MARP for 2 h after application (P = 0·036). Intra-anal gel resulted in an increase in systolic blood pressure (1 per cent gel at 2 h, P = 0·042; 3 per cent gel at 4 h, P = 0·017). One per cent intra-anal and rectal gels caused a decrease in the pulse rate for 2 h after application (P = 0·012 and P = 0·018 respectively). Six subjects complained of nausea and three of headache after gel application.

Conclusion

Intra-anal and rectal gel produced a sustained rise in MARP with rapid onset in volunteers. This raises the possibility of a therapeutic application for l-erythro methoxamine in patients with passive incontinence and internal anal sphincter dysfunction.

Sacral neuromodulation in treatment of fecal incontinence following anterior resection and chemoradiation for rectal cancer

PURPOSE

Fecal incontinence may occur in patients who have undergone anterior resection for rectal cancer without presenting sphincter lesions. Chemoradiation may contribute to disrupting continence mechanisms. Treatment is controversial. Assessment of fecal incontinence in patients who agreed to integrate treatment for rectal cancer and treatment with sacral neuromodulation are reported.

METHODS

Fecal incontinence following preoperative chemoradiation and anterior resection for rectal cancer was evaluated in four patients. A good response was observed during the percutaneous sacral nerve evaluation test, and so permanent implant of sacral neuromodulation system was performed. Reevaluation was performed at least two months after implant.

RESULTS

After device implantation, the mean fecal incontinence scores decreased, and the mean number of incontinence episodes dropped from 12.0 to 2.5 per week (P < 0.05). Permanent implant resulted in a significant improvement in fecal continence in three patients, and incontinence was slightly reduced in the fourth. Manometric parameters agreed with clinical results: maximum and mean resting tone and the squeeze pressure were normal in three patients and reduced in one. In these same three patients, neorectal sensation parameters increased when the preoperative value was normal or below normal and decreased when the preoperative value was higher than normal, whereas in one patient in whom extremely low values were recorded all of the parameters decreased significantly.

CONCLUSIONS

Fecal incontinence following anterior resection and neoadjuvant therapy should be carefully evaluated. If a suspected neurogenic pathogenesis is confirmed, sacral neuromodulation may be proposed. If the test results are positive, permanent implant is advisable. Failure of this approach does not exclude the use of other, more aggressive treatment.

Topical phenylephrine in the treatment of radiation-induced faecal incontinence

AIMS

Acute bowel toxicity after pelvic radiotherapy is defined as occurring within 3 months of the start of treatment; chronic gastrointestinal toxicity may continue after the acute phase or start after a latent period. One in five patients develop chronic faecal incontinence affecting quality of life; how best to treat these patients is not known. This retrospective study aimed to determine the effects of a new agent, phenylephrine gel, in the treatment of chronic radiation-induced faecal incontinence.

MATERIALS AND METHODS

Patients prescribed phenylephrine gel for new-onset faecal incontinence after radiotherapy were identified from our database of patients treated in a specialist radiation-induced bowel damage clinic since 2000. Changes in the level of faecal incontinence were assessed using the Vaizey faecal incontinence scoring system before and after treatment.

RESULTS

Fifteen patients (nine men and six women) of mean age 70.5 years (standard deviation 8.2, age range 56-82 years) were treated with phenylephrine gel a median of 43 months after completing radiotherapy. The median Vaizey score before treatment with phenylephrine gel was 17 (interquartile range [IQR] 14-20) and after treatment was 14 (IQR 11-18) (P = 0.005). The median length of treatment with phenylephrine gel was 28 days (IQR 28-365). Scores improved in 11 out of 15 patients; four out of 15 patients showed substantial improvements of 7 or more points; and seven patients considered the gel helpful.

CONCLUSION

Topical phenylephrine gel for the treatment of radiation-induced faecal incontinence has not been previously reported. This small, retrospective study suggests that it may help most patients and, in some, the improvement may be substantial. However, larger placebo-controlled prospective studies are required.

[Fecal incontinence]

Diagnosis and management of fecal incontinence requires exact understanding of the anatomic and pathophysiologic principles involved and demands a methodical, stepwise approach. Despite the potential appeal of surgical intervention, a considerable number of patients can be helped by comparatively simple, noninvasive measures. Initial treatment should be medical, including biofeedback in combination with a bowel management program. In the presence of a severely denervated pelvic floor, physiotherapeutic techniques rarely give rise to a satisfactory and long-lasting response. Obvious external sphincter defects and patients who failed medical management are treated surgically. Many injuries of the external sphincter can be treated by direct sphincter repair. If patients with intact external sphincters are unresponsive to medical measures, descending perineum and resultant idiopathic fecal incontinence will improve by radio-frequency delivery, sacral nerve stimulation, or postanal plication. Patients with complex neurologic disorders or extensive sphincter defects or who have undergone previous unsuccessful attempts at repair of the puborectalis itself should be considered for dynamic gracilis plastic or an artificial sphincter.

Faecal incontinence in adults

Faecal incontinence can affect individuals of all ages and in many cases greatly impairs quality of life, but incontinent patients should not accept their debility as either inevitable or untreatable. Education of the general public and of health-care providers alike is important, because most cases are readily treatable. Many cases of mild incontinence respond to simple medical therapy, whereas patients with more advanced incontinence are best cared for after complete physiological assessment. Recent advances in therapy have led to promising results, even for patients with refractory incontinence. Health-care providers must make every effort to communicate fully with incontinent patients and to help restore their self-esteem, eliminate their self-imposed isolation, and allow them to resume an active and productive lifestyle.

Clinical skills: nursing considerations in patients with faecal incontinence

Faecal incontinence is a distressing and socially debilitating problem. Nurses are ideally placed to support patients and assist them in improving their quality of life. In order to provide the necessary holistic care the nurse needs to understand the nature of the patient's symptoms and be aware of a variety of management interventions. In this article the author outlines the various causes of faecal incontinence and highlights the importance of a thorough nursing assessment which takes into account the physical, psychological and social aspects of the symptoms. Planned care should be based on a firm knowledge base, but should reflect the needs of the individual. A good nurse-patient interaction facilitates this process and should be valued.

Review article: Recent trends in diagnosis and treatment of faecal incontinence

The inability to control bowel discharge is not only common but extremely distressing. It has a negative impact on a patient's lifestyle, leads to a loss of self-esteem, social isolation and a diminished quality of life. Faecal incontinence is often due to multiple pathogenic mechanisms and rarely due to a single factor. Normal continence to stool is maintained by the structural and functional integrity of the anorectal unit. Consequently, disruption of the normal anatomy or physiology of the anorectal unit leads to faecal incontinence. Currently, several diagnostic tests are available that can provide an insight regarding the pathophysiology of faecal incontinence and thereby guide management. The treatment of faecal incontinence includes medical, surgical or behavioural approaches. Today, by using logical approach to management, it is possible to improve symptoms and bowel function in many of these patients.

Review article: the management of pelvic floor disorders

Anorectal disorders, such as faecal incontinence, defecation difficulty and conditions associated with anorectal pain, are commonly encountered in the practices of gastroenterologists, urogynaecologists and colorectal surgeons. The evaluation of these disorders has been very much improved by the development and wider availability of diagnostic tests, such as manometry, endo-anal ultrasound, static and dynamic pelvic magnetic resonance imaging and electromyography. After briefly reviewing the normal anatomy and physiology of the anorectum, the pathophysiology and diagnostic approaches to faecal incontinence, defecation disorders and functional anorectal pain are discussed. Until recently, the management of these disorders has been largely anecdotal. However, our therapeutic armamentarium has been expanded by pharmacological agents, such as nitrates, calcium channel blockers and botulinum toxin, as well as the development of novel techniques, such as sacral nerve stimulation. These and other pharmacological, behavioural and surgical approaches are reviewed with respect to the robustness of evidence to support their efficacy in patients with these disorders.

L-Erythro-methoxamine is more potent than phenylephrine in effecting contraction of internal anal sphincter in vitro

BACKGROUND

Topical phenylephrine has been shown to increase resting anal canal pressure in normal and incontinent individuals. However, high concentrations of gel (10-40 per cent) are required that may cause local side-effects. The aim of this study was to determine whether methoxamine, another alpha-1-adrenoceptor agonist, might be a more potent alternative to phenylephrine.

METHODS

Porcine internal anal sphincter (IAS) tissue was cut into strips, suspended in a superfusion organ bath and allowed to equilibrate. Strips were subjected to each drug under test for 20 s, sufficient to obtain stable tone. Phenylephrine, methoxamine (1 : 1 : 1 : 1 ratio of its four isomers) and each of the individual isomers of methoxamine were evaluated in turn.

RESULTS

In vitro, methoxamine racemate and phenylephrine were similarly potent in causing contraction of IAS strips (mean(s.e.m.) dose giving half maximal effect (EC(50)) at 74.7(16.5) versus 58.3(13.4) micro M respectively; P = 0.443). However, one of the methoxamine isomers, L-erythro-methoxamine (EC(50) 17.6(3.7) micro M), was significantly more potent than the other three isomers, methoxamine racemate and phenylephrine (P = 0.002).

CONCLUSION

L-Erythro-methoxamine is four times more potent than phenylephrine and is a possible treatment for incontinence. Trials are under way to examine the efficacy of L-erythro-methoxamine in vivo.