Constipation: Diagnosis and Management

Constipation is one of the most common gastrointestinal complaints in the general population. It is associated with a diminished quality of life and increased psychological stress. Although the prevalence varies widely, the rate for chronic constipation is 15 to 20% based on epidemiologic surveys in North America. There are many causes of constipation, and its definition is imprecise and variable. Diagnosis and appropriate management are therefore difficult but extremely important. This chapter primarily focuses on the diagnosis and management of constipation as it relates to adult females. Although it is not known why more women than men experience constipation, it is possible that hormone levels, which influence the digestive system, likely contribute. Pregnancy-related constipation is also common because of both hormonal changes and pelvic floor dysfunction after pregnancy. Women also tend to experience constipation prior to menstruation. In these cases, it is most likely that fluids that would normally soften stools in the colon are retained in other parts of the body. The female anatomy may also be a factor as functional outlet obstruction can occur after changes to the pelvic floor anatomy (such as after pregnancy). Figures illustrate the Bristol Stool Chart, rectal prolapse, protrusion of the posterior vaginal wall consistent with rectocele, enterocele with vaginal prolapsed, and enterocele with bladder prolapse. Videos show rectal prolapsed, rectocele, cystocele, descended perineum, and repaired perineum. Tables list causes of functional constipation, drugs associated with constipation, diagnostic criteria for functional constipation, and Rome criteria of irritable bowel syndrome. This review contains 5 figures, 6 tables, and 99 references.

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.

Pudendal nerve injury reduces urethral outlet resistance in diabetic rats

Diabetics have voiding and continence dysfunction to which elevated levels of advanced glycation end products (AGE) may contribute. In addition, pudendal nerve injury is correlated with voiding dysfunction and stress incontinence in rats. The aim of this study was to investigate whether pudendal nerve crush (PNC) in diabetic rats alters urinary function. Female virgin Sprague-Dawley rats (144) were divided equally into diabetic, diuretic, and control groups. Half of the animals in each group were subjected to PNC, and the other half to sham PNC. Diabetes was induced 8 wk before PNC or sham PNC by streptozotocin injection (35 mg/kg). Animals underwent conscious cystometry and leak point pressure (LPP) testing 4 or 13 days after PNC or sham PNC. Tissues of half the animals were tested for levels of AGEs. Qualitative histological assessment was performed in the remaining animals. Diabetic rats 4 days after PNC voided significantly greater volume in a shorter time and with significantly less pressure than after sham PNC, suggesting that diabetic rats have a functional outlet obstruction that is relieved by PNC. LPP was significantly reduced 4 days after PNC in diabetic and diuretic animals and returned to normal 13 days after PNC. Diabetic rats with PNC demonstrated increased muscle fiber disruption and atrophy of the external urethral sphincter. AGEs were significantly elevated in diabetic rats. PNC relieves a functional outlet obstruction in diabetic rats. AGEs are elevated in diabetic rats and could play a role in urinary dysfunction and recovery from PNC.