Constipation caused by functional outlet obstruction

Ameliorating Effects of Transcutaneous Electrical Acustimulation at Neiguan (PC6) and Zusanli (ST36) Acupoints Combined with Adaptive Biofeedback Training on Functional Outlet Obstruction Constipation

Background

Stimulant laxatives are still considered the most common treatment for functional outlet obstruction constipation (FOOC). However, the effectiveness of laxatives is unsatisfactory, and the long-term use of laxatives may cause certain adverse events. With this in mind, it is, however, paramount that novel complementary treatment(s) and/or other forms of alternative medicine are adequately investigated.

Aims

The study aims to explore the effects and potential mechanism(s) of transcutaneous electrical acustimulation (TEA) combined with adaptive biofeedback training (ABT) on FOOC.

Methods

A total of forty-five patients with FOOC were recruited and were randomly assigned to receive either Macrogol 4000 Powder (MAC, 10 g bid) (group A, n = 15) only, ABT + MAC + Sham-TEA (group B, n = 15), or TEA + ABT + MAC (group C, n = 15) in a six-week study. Individual patients' constipation-symptoms (PAC-SYM) and constipation-quality of life (PAC-QOL) were both assessed and scored. Serum acetylcholine (Ach) and nitric oxide (NO) were measured from drawn blood samples while individual patients' heart rate variability (HRV) was calculated at baseline and after each corresponding therapy. Anorectal manometry and balloon expulsion test were both performed before and after treatment.

Results

Firstly, participants in group C had significantly lower scores of PAC-SYM, PAC-QOL, and a decreased anal defecating pressure (ADP) as compared to participants in group B (all p < 0.050). These results, however, suggest the TEAs effect. Secondly, the low-frequency band (LF)/(LF + HF) ratio in groups B and C were decreased as compared to group A (p=0.037, p=0.010, respectively) regarding HRV. On the other hand, the high-frequency band (HF)/(LF + HF) ratio in groups B and C showed an opposite outcome. Finally, the serum Ach in groups B and C was significantly higher as compared to group A (p=0.023, p=0.012, respectively). Of significant importance, the serum NO in groups B and C were notably low as compared to group A (p=0.001, p < 0.001, respectively).

Conclusions

TEA, combined with ABT, effectively improves constipation symptoms as well as QOL in FOOC patients. It is, however, achieved by decreasing ADP, which mechanisms are mediated via the autonomic and enteric mechanisms.

Complementary and Alternative Therapies for Chronic Constipation

Chronic constipation, an ancient disease, is prevalent, and costly in the general population. Complementary and alternative therapies are frequently used for constipation. This review introduces various methods of complementary and alternative therapies, including acupuncture, moxibustion, massage, and herbal medicine. Efficacy, safety, influence factors, sham control design, and mechanisms of these therapies are discussed and evaluated. Acupuncture or electroacupuncture was found to be most commonly used for constipation among these complementary and alternative therapies, followed by herbal medicine. Although only a small number of clinical studies are flawless, our review of the literature seems to suggest that acupuncture or electroacupuncture and herbal medicine are effective in treating constipation, whereas findings on massage and moxibustion are inconclusive. More well-designed clinical trials are needed to improve and prove the efficacy of the complementary and alternative therapies for constipation; mechanistic studies that would lead to wide spread use and improvement of the methods are also discussed in this review.

Consensus statement AIGO/SICCR diagnosis and treatment of chronic constipation and obstructed defecation (part II: treatment)

The second part of the Consensus Statement of the Italian Association of Hospital Gastroenterologists and Italian Society of Colo-Rectal Surgery reports on the treatment of chronic constipation and obstructed defecation. There is no evidence that increasing fluid intake and physical activity can relieve the symptoms of chronic constipation. Patients with normal-transit constipation should increase their fibre intake through their diet or with commercial fibre. Osmotic laxatives may be effective in patients who do not respond to fibre supplements. Stimulant laxatives should be reserved for patients who do not respond to osmotic laxatives. Controlled trials have shown that serotoninergic enterokinetic agents, such as prucalopride, and prosecretory agents, such as lubiprostone, are effective in the treatment of patients with chronic constipation. Surgery is sometimes necessary. Total colectomy with ileorectostomy may be considered in patients with slow-transit constipation and inertia coli who are resistant to medical therapy and who do not have defecatory disorders, generalised motility disorders or psychological disorders. Randomised controlled trials have established the efficacy of rehabilitative treatment in dys-synergic defecation. Many surgical procedures may be used to treat obstructed defecation in patients with acquired anatomical defects, but none is considered to be the gold standard. Surgery should be reserved for selected patients with an impaired quality of life. Obstructed defecation is often associated with pelvic organ prolapse. Surgery with the placement of prostheses is replacing fascial surgery in the treatment of pelvic organ prolapse, but the efficacy and safety of such procedures have not yet been established.

Insights from a novel model of slow-transit constipation generated by partial outlet obstruction in the murine large intestine

The mechanisms underlying slow-transit constipation (STC) are unclear. In 50% of patients with STC, some form of outlet obstruction has been reported; also an elongated colon has been linked to patients with STC. Our aims were 1) to develop a murine model of STC induced by partial outlet obstruction and 2) to determine whether this leads to colonic elongation and, consequently, activation of the inhibitory "occult reflex," which may contribute to STC in humans. Using a purse-string suture, we physically reduced the maximal anal sphincter opening in C57BL/6 mice. After 4 days, the mice were euthanized (acutely obstructed), the suture was removed (relieved), or the suture was removed and replaced repeatedly (chronically obstructed, over 24-31 days). In partially obstructed mice, we observed increased cyclooxygenase (COX)-2 levels in muscularis and mucosa, an elongated impacted large bowel, slowed transit, nonpropagating colonic migrating motor complexes (CMMCs), a lack of mucosal reflexes, a depolarized circular muscle with slow-wave activity due to a lack of spontaneous inhibitory junction potentials, muscle hypertrophy, and CMMCs in mucosa-free preparations. Elongation of the empty obstructed colon produced a pronounced occult reflex. Removal of the obstruction or addition of a COX-2 antagonist (in vitro and in vivo) restored membrane potential, spontaneous inhibitory junction potentials, CMMC propagation, and mucosal reflexes. We conclude that partial outlet obstruction increases COX-2 leading to a hyperexcitable colon. This hyperexcitability is largely due to suppression of only descending inhibitory nerve pathways by prostaglandins. The upregulation of motility is suppressed by the occult reflex activated by colonic elongation.

Consensus statement AIGO/SICCR diagnosis and treatment of chronic constipation and obstructed defecation (Part II: Treatment)

The second part of the Consensus Statement of the Italian Association of Hospital Gastroenterologists and Italian Society of Colo-Rectal Surgery reports on the treatment of chronic constipation and obstructed defecation. There is no evidence that increasing fluid intake and physical activity can relieve the symptoms of chronic constipation. Patients with normal-transit constipation should increase their fibre intake through their diet or with commercial fibre. Osmotic laxatives may be effective in patients who do not respond to fibre supplements. Stimulant laxatives should be reserved for patients who do not respond to osmotic laxatives. Controlled trials have shown that serotoninergic enterokinetic agents, such as prucalopride, and prosecretory agents, such as lubiprostone, are effective in the treatment of patients with chronic constipation. Surgery is sometimes necessary. Total colectomy with ileorectostomy may be considered in patients with slow-transit constipation and inertia coli who are resistant to medical therapy and who do not have defecatory disorders, generalised motility disorders or psychological disorders. Randomised controlled trials have established the efficacy of rehabilitative treatment in dys-synergic defecation. Many surgical procedures may be used to treat obstructed defecation in patients with acquired anatomical defects, but none is considered to be the gold standard. Surgery should be reserved for selected patients with an impaired quality of life. Obstructed defecation is often associated with pelvic organ prolapse. Surgery with the placement of prostheses is replacing fascial surgery in the treatment of pelvic organ prolapse, but the efficacy and safety of such procedures have not yet been established.

Consensus statement AIGO/SICCR diagnosis and treatment of chronic constipation and obstructed defecation (part II: treatment)

The second part of the Consensus Statement of the Italian Association of Hospital Gastroenterologists and Italian Society of Colo-Rectal Surgery reports on the treatment of chronic constipation and obstructed defecation. There is no evidence that increasing fluid intake and physical activity can relieve the symptoms of chronic constipation. Patients with normal-transit constipation should increase their fibre intake through their diet or with commercial fibre. Osmotic laxatives may be effective in patients who do not respond to fibre supplements. Stimulant laxatives should be reserved for patients who do not respond to osmotic laxatives. Controlled trials have shown that serotoninergic enterokinetic agents, such as prucalopride, and prosecretory agents, such as lubiprostone, are effective in the treatment of patients with chronic constipation. Surgery is sometimes necessary. Total colectomy with ileorectostomy may be considered in patients with slow-transit constipation and inertia coli who are resistant to medical therapy and who do not have defecatory disorders, generalised motility disorders or psychological disorders. Randomised controlled trials have established the efficacy of rehabilitative treatment in dys-synergic defecation. Many surgical procedures may be used to treat obstructed defecation in patients with acquired anatomical defects, but none is considered to be the gold standard. Surgery should be reserved for selected patients with an impaired quality of life. Obstructed defecation is often associated with pelvic organ prolapse. Surgery with the placement of prostheses is replacing fascial surgery in the treatment of pelvic organ prolapse, but the efficacy and safety of such procedures have not yet been established.

Constipation of anorectal outlet obstruction: pathophysiology, evaluation and management

Constipation is a subjective symptom of various pathological conditions. Incidence of constipation fluctuates from 2 to 30% in the general population. Approximately 50% of constipated patients referred to tertiary care centers have obstructed defecation constipation. Constipation of obstructed defecation may be due to mechanical causes or functional disorders of the anorectal region. Mechanical causes are related to morphological abnormalities of the anorectum (megarectum, rectal prolapse, rectocele, enterocele, neoplasms, stenosis). Functional disorders are associated with neurological disorders and dysfunction of the pelvic floor muscles or anorectal muscles (anismus, descending perineum syndrome, Hirschsprung's disease). However, this type of constipation should be differentiated by colonic slow transit constipation which, if coexists, should be managed to a second time. Assessment of patients with severe constipation includes a good history, physical examination and specialized investigations (colonic transit time, anorectal manometry, rectal balloon expulsion test, defecography, electromyography), which contribute to the diagnosis and the differential diagnosis of the cause of the obstructed defecation. Thereby, constipated patients can be given appropriate treatment for their problem, which may be conservative (bulk agents, high-fiber diet or laxatives), biofeedback training or surgery.