Relationship between outlet obstruction constipation and obstructed urinary flow

Chemotherapy-Induced Constipation and Diarrhea: Pathophysiology, Current and Emerging Treatments

Gastrointestinal (GI) side-effects of chemotherapy are a debilitating and often overlooked clinical hurdle in cancer management. Chemotherapy-induced constipation (CIC) and Diarrhea (CID) present a constant challenge in the efficient and tolerable treatment of cancer and are amongst the primary contributors to dose reductions, delays and cessation of treatment. Although prevalence of CIC is hard to estimate, it is believed to affect approximately 16% of cancer patients, whilst incidence of CID has been estimated to be as high as 80%. Despite this, the underlying mechanisms of both CID and CIC remain unclear, but are believed to result from a combination of intersecting mechanisms including inflammation, secretory dysfunctions, GI dysmotility and alterations in GI innervation. Current treatments for CIC and CID aim to reduce the severity of symptoms rather than combating the pathophysiological mechanisms of dysfunction, and often result in worsening of already chronic GI symptoms or trigger the onset of a plethora of other side-effects including respiratory depression, uneven heartbeat, seizures, and neurotoxicity. Emerging treatments including those targeting the enteric nervous system present promising avenues to alleviate CID and CIC. Identification of potential targets for novel therapies to alleviate chemotherapy-induced toxicity is essential to improve clinical outcomes and quality of life amongst cancer sufferers.

Functional anorectal disorders

Functional anorectal disorders include solitary rectal ulcer syndrome, rectocele, nonrelaxing puborectalis syndrome, and descending perineal syndrome. Patients usually present with "constipation," but the clinical picture of these disorders includes rectal pain and bleeding, digitalization, incomplete evacuation, and a feeling of obstruction. Diagnosis is difficult because many findings can be seen in normal patients as well. The diagnosis is made by using a combination of clinical picture, defecography, pathology, and occasionally anometry and pudendal terminal motor nerve latency. These disorders are generally treated medically with dietary changes and biofeedback. Surgical intervention is reserved for patients with intractable symptoms and has not been universally successful.

Predictive value of impaired evacuation at proctography in diagnosing anismus

OBJECTIVE

We aimed to determine the positive predictive value of impaired evacuation during evacuation proctography for the subsequent diagnosis of anismus.

SUBJECTS AND METHODS

Thirty-one adults with signs of impaired evacuation (defined as the inability to evacuate two thirds of a 120 mL contrast enema within 30 sec) during evacuation proctography underwent subsequent anorectal physiologic testing for anismus. A physiologic diagnosis of anismus was based on a typical clinical history of the condition combined with impaired rectal balloon expulsion or abnormal surface electromyogram.

RESULTS

Twenty-eight (90%) of the 31 patients with impaired proctographic evacuation were found to have anismus at subsequent physiologic testing. Among the 28 were all 10 patients who evacuated no contrast medium and all 11 patients with inadequate pelvic floor descent, giving evacuation proctography a positive predictive value of 90% for the diagnosis of anismus. A prominent puborectal impression was seen in only three subjects during proctography, one of whom subsequently showed no physiologic sign of anismus.

CONCLUSION

Impaired evacuation during evacuation proctography is highly predictive for diagnosis of anismus.

Clinical applications and techniques of cinedefecography

BACKGROUND

Cinedefecography is of value in routine examination of functional disorders of the pelvic floor. Interest in this technique has rapidly expanded owing to the increased availability of colorectal physiologic testing and better understanding of the multifactorial pathophysiology involving evacuation disorders.

METHODS

A summary of the available techniques, methodology, and indications for cinedefecography was undertaken. In addition, information was provided on interpretation of these images particularly in the context of anatomic abnormalities and clinical applications.

RESULTS

Cinedefecography can be rapidly and easily performed using standard radiographic equipment. Effective radiation dose is significantly lower than for other intestinal contrast studies. The technique has been found most useful for measurements of perineal descent, puborectalis length, and ascertaining the function of the puborectalis muscle and pelvic floor. Common diagnoses that can be made by this test include nonrelaxing puborectalis syndrome, perineal descent, rectocele, enterocele, sigmoidocele, and rectoanal intussusception.

CONCLUSION

Cinedefecography provides a wide range of information to assist the surgeon with the evaluation and management of patients with evacuatory and other associated pelvic floor disorders.

Effect of Magnetic Stimulation on the Contractile Activity of the Rectum in Humans

Magnetic stimulation (MS) has been used to activate the neuromuscular tissue by inducing an electric field. Based on the results of a recent study on a canine model (Eur Surg Res 1998;30:268–72), which demonstrated that sacral MS effected a rectal and vesical pressure rise and a drop of rectal neck (anal canal) pressure, thereby achieving evacuation, the test was performed on 28 healthy volunteers (mean age, 36.6 years; 18 men and 10 women). The rectal, rectal neck, and vesical pressures were recorded during sacral MS with a magnetic coil while the rectum was empty and distended by a balloon. Electromyographic activity of the two rectus abdominis muscles was determined to exclude the possible interference of intra-abdominal pressure with the MS recordings. Stimulation parameters were set at 70 per cent intensity, 40-Hz frequency, and 1-to 2-second burst length. Sacral MS effected significant rectal and vesical pressure rise ( P < 0.01 and P < 0.01, respectively) and drop of rectal neck pressure ( P < 0.01). Intermittent stimulation induced balloon expulsion from the rectum. The two rectus abdominis muscles did not show change in electromyographic activity during MS, indicating that the rectal and vesical pressure rise was not due to increased intra-abdominal pressure. Sacral MS induced rectal evacuation with no adverse effects. The method is simple, easy, safe, and noninvasive and is suggested to be applied for the treatment of the inertic or neuropathic rectum. As the vesical pressure proved to be elevated too, MS might also be used for rectal and vesical evacuation in patients with spinal cord lesions.

Novel approach to combined defaecation and micturition disorders with rectovaginovesicopexy

BACKGROUND

This study was conducted to investigate the results of rectovaginovesicopexy (RVVP) in patients with combined defaecation and micturition disorders. RVVP was developed from a standard procedure for different forms of defaecation disorders (the rectovaginopexy (RVP)). It is only a limited extension to the RVP and results in elevation of all three pelvic compartments.

METHODS

In a consecutive series of 25 patients the effects or RVVP were evaluated prospectively. Information about the clinical history and results was obtained by a standard questionnaire filled out before and 3 and 12 months after operation. Dynamic defaecography was performed before and 3 months after RVVP. Before operation urodynamic studies were conducted.

RESULTS

RVVP improved constipation (14 of 18 patients improved, P = 0.001), faecal incontinence (11 of 16 patients improved, P = 0.005) and dysfunctional voiding (ten of 16 patients improved, P = 0.07) without induction of these disorders. Overall urinary incontinence improved in 11 of 22 patients (P = 0.18), with deterioration of urinary incontinence in three and induction of urinary incontinence in two of the patients. Patients with isolated urinary stress incontinence fared better (eight of 13 patients improved) than those with mixed urinary incontinence.

CONCLUSION

RVVP provides satisfactory improvement of combined defaecation and micturition disorders. The benefits of a limited extension of the RVP seem to outweigh potential side-effects such as deterioration or de novo defaecation or micturition disorders.

Role of segmental colonic transit time studies to select patients with slow transit constipation for partial left-sided or subtotal colectomy

This prospective study investigated the value of segmental colonic transit time studies in the surgical treatment of slow transit constipation. Overall, 346 patients with chronic constipation were analysed; slow transit constipation was diagnosed in 86 (25 per cent). Based on the results of segmental colonic transit time studies, 18 patients underwent partial left-sided colectomy and 24 subtotal colectomy. Recurrent constipation was seen in three of 18 patients and seven of 24 respectively. Severe abdominal discomfort was noted in six of 18 and 15 of 24 respectively. Disabling diarrhoea and faecal incontinence developed in two of 14 and five of 20 patients with an anastomosis respectively. Although these results indicate that segmental colonic transit time studies are useful in selecting patients with slow transit constipation for partial left-sided or subtotal colectomy, both procedures should be performed with prudence.

Anterior rectocele and anorectal dysfunction

The two types of anterior rectocele, "distension" of Type 1 rectocele (T1R) and "displacement" or Type 2 rectocele (T2R), have different anatomical, clinical and therapeutic profiles. The aim of this study was to assess anorectal function in patients with distension or displacement rectocele. Three groups of female patients and one group of healthy female subjects were studied. Both the 10 Group 1 subjects, who had been diagnosed as having T1R, and 10 Group 2 women who had been diagnosed as having T2R, were symptomatic for digital evacuation of the rectum. The 10 Group 3 females had complained of sever idiopathic constipation but had no defecatory disorders. The control group was made up to 10 healthy volunteers. All patients and controls underwent clinical evaluation, colonic transit time (CTT), computerized anorectal manometry (CAM), and defecography. Bowel movements and clinical evaluation were similar for both rectocele groups. In Group 1, CAM detected significantly higher anal pressure (P < 0.05) and more impaired rectoanal inhibitory reflex (RAIR) (P < 0.01) in comparison to the other patients and controls. In Group 2, the lowest anal pressure (P < 0.001) was noted but RAIR was normal. Defecographic results, at rest and during evacuation, showed a significantly (P < 0.001) higher anorectal angle and a more abnormal pelvic floor descent in Group 2 than in the other study groups and controls. Therefore, peculiar anorectal function was present in patients with anterior rectocele. A pelvic floor dyssynergia was noted in the distension rectocele group, while a fall of the pelvic floor was noted in the displacement rectocele group.

The assessment of constipation in terminal cancer patients admitted to a palliative care unit: a retrospective review

Constipation is a frequent and distressing complication in patients with advanced cancer. However, very few studies have reviewed the assessment and management of these patients. The purpose of this study was to review the documentation and assessment and diagnosis of constipation in patients admitted to a Palliative Care Unit, and the correlation between those findings and radiological evidence of stool in the colon. The records of 122 consecutive patients admitted to the Palliative Care Unit, Edmonton General Hospital were reviewed in order to assess the physician's and the nurse's record of symptoms, physical findings, and diagnosis and treatment of constipation. All patients also underwent a flat abdominal radiograph that scored for the presence of stool in the colon (0 = no stool; and 12 = stool occupying all the lumen of the four quadrants of the colon). The radiograph was scored blindly by two different physicians. Of 103 evaluable patients, a rectal exam was reported only in 42. Correlation between the assessment by the two physicians' radiograph score was high (0.78, P nd nurses' diagnosis of constipation, the presence of laxative treatment, the number of days since the last bowel movement, and the source of the admission (hospital vs home) were not associated with higher radiological scores for constipation. Assessment is insufficient in this population at high risk for severe constipation. Radiological examination may be necessary for adequate diagnosis in some patients. More research is needed in this area.

Idiopathic slow-transit constipation

Until recently, the surgical management of idiopathic slow-transit constipation had remained unchanged since the condition was first described by Arbuthnot Lane in 1908. Although colectomy and ileorectal anastomosis is a successful treatment for the majority of patients, symptoms persist or are worse in some cases following such surgery. The previously inaccessible colon is now an area of interest in both health and disease; recent observations on aetiology, clinical investigation, neuropathology and surgical outcome lead us to question the rationale of colectomy for all patients with severe constipation.

Obstructed defecation

Obstructed defecation is one of the causes of chronic constipation. Clinical tests suggest that patients with obstructed defecation have impaired pelvic floor function. Appropriate management relies on proper identification of the underlying pathophysiology.

Cinedefecography and electromyography in the diagnosis of nonrelaxing puborectalis syndrome

A prospective study was undertaken to assess the correlation between electromyography (EMG) and cinedefecography (CD) for the diagnosis of nonrelaxing puborectalis syndrome (NRPR). Clinical criteria for NRPR included straining, incomplete evacuation, tenesmus, and the need for enemas, suppositories, or digitation. EMG criteria included failure to achieve a significant decrease in electrical activity of the puborectalis (PR) during attempted evacuation. CD criteria included either paradoxical contraction or failure of relaxation of the PR along with incomplete evacuation. In addition, other etiologies for incomplete evacuation, such as rectoanal intussusception or nonemptying rectocele, were excluded by proctoscopy and defecography in all cases. One hundred twelve patients with constipation, 81 females and 31 males, with a mean age of 59 (range, 12-83) years were studied by routine office evaluation, CD, and EMG. Forty-two patients (37 percent) had evidence of NRPR on CD (rectal emptying: none, 24; incomplete, 18). Twenty-eight of these patients (67 percent) also had evidence of NRPR on EMG. EMG findings of NRPR were present in 12 of 70 patients (17 percent) with normal rectal emptying. Conversely, 14 of 72 patients (19 percent) with normal PR relaxation on EMG had an NRPR pattern on CD. The sensitivity and specificity for the EMG diagnosis of NRPR were 67 percent and 83 percent, and the positive and negative predictive values were 70 percent and 80 percent, respectively. Conversely, if EMG is considered as the ideal test for the diagnosis of NRPR, CD had a sensitivity of 70 percent, a specificity of 80 percent, and positive and negative predictive values of 66 percent and 82 percent, respectively. In summary, sensitivity, specificity, and predictive values of EMG and CD are suboptimal. Therefore, a combination of these two tests is suggested for the diagnosis of NRPR.