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AD_ 0 3 3 _ SEPT 1 9 _ 0 8 . PDF Pa ge 1 9 / 1 0 / 0 8 , 5 : 0 7 PM How to treat Pull-out section w w w. a u s t r a l i a n d o c t o r. c o m . a u Complete How to Treat quizzes online (www.australiandoctor.com.au/cpd) to earn CPD or PDP points. inside Causes of constipation History and examination Investigations General practice treatment Specialist intervention and the GP’s ongoing role The authors CONSTIPATION DR VID SUTTOR, gastroenterology advanced trainee (final year) and motility research fellow, gastrointestinal investigation unit, Royal North Shore Hospital, St Leonards, and University of Sydney, NSW. Background WHEN constipation is described by patients, it usually refers to the passage of hard or infrequent stools, but each patient’s perception of the problem may differ. Constipation has been defined by the International Rome Committee for Gastrointestinal Disorders as being the presence of at least two of the following symptoms for at least one-quarter of the time: ■ Straining. ■ Epidemiology ■ Constipation is common in the general population, with a prevalence of 15-20%. In patients under 50, women are twice as likely to be affected as men, while the prevalence converges in older age groups (20% in men vs 25% in women). Groups that are more likely to be affected include the elderly, children, pregnant women, bedridden Lumpy or hard stools. Sensation of incomplete evacuation. ■ Sensation of anorectal obstruction. ■ Manual manoeuvres to facilitate defaecation. ■ Fewer than three defaecations a week. Some patients self-manage, but many present to their GPs for additional help. There is a subset that may need to be referred for specialist management for chronic refractory symptoms. patients and those who have undergone certain types of surgery such as gynaecological procedures. In a NSW survey, only one-third of the young women and half of the middle-aged and older women with constipation had sought help for treatment of their condition, but constipation still represents a major reason for patients to present to their GPs. DR ALLISON MALCOLM, staff specialist gastroenterologist, department of gastroenterology and gastrointestinal investigation unit, Royal North Shore Hospital, St Leonards, and in private practice in Chatswood, NSW. Australian Doctor e-newsletter Subscribe for FREE at www.australiandoctor.com.au Daily news and opinion from a source you can trust www.australiandoctor.com.au 19 September 2008 | Australian Doctor | 33 AD_035___SEPT19_08 Page 2 10/9/08 4:57 PM Causes of constipation Dietary DEFICIENCY of fibre and fluids can frequently lead to hard and lumpy stools that can be difficult to evacuate. For the general population, Australian NHMRC guidelines recommend intake of 25g of fibre a day for women, and 30g a day for men. NHMRC guidelines also recommend 1.5L of water a day for the general population, in mild climates. In hotter parts of Australia or with increased losses such as with exercise, and especially in patients with constipation, a higher intake of fluid may be needed to prevent dehydration, which can contribute to constipation. Medications The onset of constipation may be temporally linked to starting certain medications, and a careful review of the list of medications needs to be undertaken. Table 1 provides a list of some medications commonly linked to constipation, although a vast number of medications may have GI side effects in some patients. Organic disease Mechanical obstruction from colorectal malignancy is important to consider, given the background prevalence of colorectal cancer in the community (one in 12 up to age 85). Diseases affecting neurohormonal or structural factors that co-ordinate movement of stool through the intestine can also lead to constipation (table 2). Slow colonic transit A subgroup of patients with chronic constipation has slow transit constipation (colonic inertia), in which the underlying pathophysiology may be related to neuropathy of the colonic nerve plexus. This Table 2: Causes of constipation Table 1: Common medications linked to constipation Grouping Examples Antispasmodics Hyoscine, mebeverine Antipsychotics Lithium, clozapine, olanzapine, haloperidol Analgesics Codeine, oxycodone, morphine Antidiarrhoeals Loperamide Calcium-channel antagonists Nifedipine, amlodipine Antacids Calcium carbonate-containing antacid agents Neurological disorders ■ Cerebrovascular accident ■ Spinal cord lesions ■ Multiple sclerosis ■ Parkinson’s disease ■ Autonomic neuropathy ■ Hirschsprung’s disease ■ Neurofibromatosis Calcium supplements Metabolic states/ disorders Iron supplements ■ Diabetes mellitus ■ Hypothyroidism ■ Pregnancy ■ Hypopituitarism ■ Hypercalcaemia/ hypokalaemia ■ Porphyria ■ Paraneoplastic group of patients can represent one-third of constipated patients referred to tertiary centres. Colonic transit may also be delayed because of organic conditions or medications, as well as variable factors such as physical or emotional stress, and disturbance of the sleep-wake cycle. The increased time for stool transit through the colon allows longer mucosal contact time, leading to increased water absorption from the stool and hence harder stool consistency. Simple management approaches and lifestyle modifications may not be sufficient for some patients with severely delayed colonic transit, who often require use of osmotic agents, and sometimes even (as a last resort) subtotal colectomy (see Indications for surgery, page 38). Excess straining. ■ A sense of anal blockage. ■ A sense of incomplete evacuation. ■ Use of digital manoeuvres or unusual positions to facilitate evacuation. Although stool reaches the rectum, these patients cannot evacuate effectively, so symptoms of constipation can result. This is because such patients demonstrate poor co-ordination of abdominal, anorectal and pelvic floor muscles, leading to an abnormal defaecatory manoeuvre. As a result, they are either unable to achieve adequate rectal pressure to initiate defaecation, or display either absent anal relaxation or paradoxical anal contraction during defaecation (resulting in a sensation of obstructed defaecation, and often leading to constipation). Pelvic floor dyssynergia Functional constipation A proportion of patients with constipation have abnormal or obstructed defaecation. This is an acquired disorder in most patients, although a small proportion of patients have not learned normal defaecation adequately in childhood. Symptoms of pelvic floor dyssynergia include: The most widely accepted definition of functional constipation, the Rome III criteria, is based on consensus criteria developed by an international panel of experts. According to Rome III, the following criteria must be fulfilled for three months, with symptom onset at least six months ■ Collagen or muscle disorders ■ Systemic sclerosis ■ Amyloidosis ■ Dystrophia myotonica ■ Dermatomyositis Structural disorders ■ Colorectal cancer ■ Colonic stricture Functional disorders ■ Functional constipation ■ Irritable bowel syndrome ■ Pelvic floor dyssynergia ■ Colonic inertia before diagnosis of functional constipation. 1. Inclusion of two of the following: a. straining for *25% of defaecations. b. lumpy or hard stools in *25% of defaecations. c. sensation of incomplete evacuation after *25% of defaecations. d. sensation of anorectal blockage during *25% of defaecations. e. manual manoeuvres for *25% of defaecations. f. fewer than three defaecations per week. 2. Loose stools rarely present without use of laxatives. 3. Insufficient criteria for irritable bowel syndrome (IBS). Irritable bowel syndrome with constipation The defining feature of IBS is the presence of abdominal pain associated with, or relieved by, defaecation. Of course constipation may also occur within the setting of IBS, which is a common condition, and this combination affects a significant number of patients presenting to GPs. Although IBS has been known to account for up to 50% of patient referrals to specialist physicians, a further proportion of people with IBS in the community defer seeking medical attention, either because of embarrassment or lack of confidence. The ability of the treating medical practitioner to establish a constructive therapeutic relationship with the patient has been shown to reduce the level of frustration and hopelessness that patients often experience. However, a successful outcome requires more than just a good relationship — an understanding of the multifaceted nature of this condition is also helpful. While the aetiology and pathophysiology of IBS are still under investigation, disordered colonic motility, aberrant visceral sensitivity, and altered neural processing of gut stimulation are deemed to be central mechanisms in the evolution of this syndrome. To date, pharmacological therapy has been used to target: ■ Improving abdominal pain (resulting from visceral sensitivity and abnormal neural processing). ■ Regulating the altered motility and sphincter function. ■ Altering the stool form to facilitate defaecation. In addition, medications to manage psychiatric disorders may also be needed, as concomitant depression and anxiety may contribute to poor outcomes in patients with severe IBS. Overlapping disorders Investigations of patients with refractory constipation referred to tertiary centres have revealed a significant degree of overlap in the causes of constipation, with slow colonic transit being found in 47% of patients, overlapping with visceral hypersensitivity indicative of IBS in 58%, and pelvic floor dyssynergia in 59%. However, no physiological abnormalities are found in 24% of patients, which is in itself indicative of functional con1 stipation. Hence patients diagnosed with IBS on clinical grounds should also be considered for possible concomitant causes of constipation, as this may guide further investigation and options for therapy, eg, biofeedbacktherapy for functional constipation and pelvic floor dyssynergia (see Specialist intervention and the GP’s ongoing role, page 38). History and examination History A thorough history reviewing stool frequency and consistency, current and past use of laxatives, and pelvic floor inco-ordination symptoms should be undertaken. Patients may complain of straining to defaecate even with soft or watery stools, or may define themselves as being constipated because they have a sensation of anorectal obstruction or pain. Occasionally patients may even present with diarrhoea or faecal incontinence when severe constipation with ‘overflow’ is present. A review of background medical comorbidities and a medication history may provide a clue to underlying organic pathology. A family history of bowel dysfunction or laxative use may be present in up to one-third of patients. Further review of dietary history, including fibre and water intake, timing of meals, and a tendency to skip breakfast should be discussed. After waking, a morning meal is the strongest physiological stimulus of colonic motor activity, and a tendency to skip breakfast may have repercussions for daily colonic transit. A review of caffeine and alcohol intake should be included in the dietary history. Symptoms of anxiety or depression should also be sought. Finally, a prior obstetric history and review of past surgical procedures, including back operations, may also provide a clue to the aetiology of the constipation. In particular, it has recently been reported that constipation is more common after hysterectomy. Breakfast provides a strong physiological stimulus of colonic motor activity. Physical examination Physical examination with palpation of the abdomen to check for masses or a faecally loaded sigmoid colon, as well as a digital rectal examination to examine for faecal impaction, an anal fissure, haemorrhoids or a rectocoele is essential. In addition, a thorough general examination including assessment for thyroid disorders and neurological disorders such as Parkinson’s disease is important. www.australiandoctor.com.au 19 September 2008 | Australian Doctor | 35 AD_ 0 3 6 _ _ _ SEPT 1 9 _ 0 8 . PDF Pa ge 1 9 / 1 0 / 0 8 , 5 : 0 9 PM How to treat – constipation Investigations INITIAL blood tests should include FBC, serum calcium, blood glucose level and thyroid function testing. An abdominal X-ray to look for faecal loading may be useful in some patients. A colonoscopy should be considered in all patients with warning signs for malignancy, such as: ■ Altered bowel habit. ■ Overt or occult rectal bleeding. ■ Iron deficiency anaemia. ■ Loss of appetite. ■ A history of colonic polyps or neoplasia. ■ A relevant family history of colonic malignancy. Barium enema can also be useful in excluding structural abnormalities, as can defaecography for detecting a rectocoele with stool retention. Other imaging such as CT or ultrasound scanning should be considered in cases with abdominal distension if there is suspicion of other pathology such as ovarian cancer. Figure 1: A: Normal colonic transit study, demonstrating clearance of tracer by day 4-5. B: Slow colonic transit study, demonstrating persistence of tracer at day 5. A B Anorectal manometry Colonic transit study A nuclear medicine colonic transit study can provide valuable information in patients with chronic constipation when the above measures have been unhelpful. For this study a radioactive tracer mixed with water is ingested, and clearance of the tracer is assessed. Figure 1A shows a normal colonic transit study in which there has been almost complete clearance of the tracer by day 4. Figure 1B shows slow transit constipation, where much activity remains in the colon even after day 5. The identification of slow colonic transit can help guide therapy for these patients. In patients with symptoms suggesting pelvic floor inco-ordination, an anorectal manometry study can confirm the diagnosis. In patients with symptoms suggesting pelvic floor incoordination, an anorectal manometry study can confirm the diagnosis and allow formulation of a management plan. A comprehensive anorectal physiology study uses a balloon attached to pressure-sensing catheters that provide information on: ■ The length of the anal canal. ■ Resting and squeeze anal sphincter pressures. ■ The degree of anal sphincter relaxation or paradoxical contraction on straining. ■ Rectal pressures on straining. ■ Rectal sensation. The balloon expulsion test involves inflating a rectal balloon with 50mL warm water then asking the patient to expel this while seated on a commode (to simulate normal toileting behaviour). Patients unable to expel the balloon from the rectum within 60 seconds are highly likely to have pelvic floor dyssynergia. Anorectal manometry can also exclude the diagnosis of Hirschsprung’s disease. Absence of normal reflex relaxation of the internal anal sphincter after distension of a balloon in the rectum indicates absence of mediation by the myenteric plexus. Figure 2 demonstrates the layout in a typical anorectal manometry laboratory. Figure 2: Manometry-based biofeedback therapy clinic at Royal North Shore Hospital, St Leonards, NSW. General practice treatment modalities Diet, water and lifestyle measures MANY patients with chronic constipation are unaware of simple dietary modifications that can alleviate their symptoms. Increasing the amount of dietary fibre products, along with NHMRC recommendations for two serves of fruit and five serves of vegetables daily (1-2 serves extra of each in pregnancy), and including cereal products (4-12 serves for men and 4-9 serves for women daily) (table 3), should be enough to provide daily fibre requirements. However, some patients may require additional fibre, either dietary or supplemental. Types of supplemental fibre include psyllium (Metamucil), ispaghula husk (Fybogel), guar gum (Benefiber) and sterculia (Normafibe). The dosing for these agents starts at 1-2 teaspoons once or twice daily with meals and can be adjusted according to the patient’s needs. Most patients require at least 30g of fibre daily, and a commitment of regular intake for at least one week is needed to reach a steady state in terms of dosing and result. In addition, all fibre intake must be combined with adequate intake of fluid (minimum of 1.5L a day) to be effective, and this fluid intake should be specified to be in the form of non-caffeinated and non-alcoholic beverages. Regular exercise is generally recommended in the management of constipation, although there is little formal evidence in the literature to support it. This suggestion stems from the link between constipation and sedentary lifestyles in epidemiological studies. Apart from exercise, other simple measures include encouraging patients to adhere to regular meal times (in particular, to avoid missing breakfast), and to attempt a bowel movement in the morning after breakfast and within the first two hours of waking (to take advantage of the gastrocolonic response). Medical therapy Laxatives form the mainstay of therapy when simple measures targeting diet and lifestyle factors fail. Table 4 lists agents commonly used. Stool softeners Patients commonly use over-the-counter stool softeners such as Coloxyl (docusate sodium) although there is little evidence for their use in isolation (level III evidence). The recommended dosage is 1-2 tablets once or twice daily. They can be useful in improving stool form to a better consistency that is easier to evacuate. They are also useful as adjunctive therapy in patients with complications such as anal fissure (see Specialist intervention and the GP’s ongoing role, page 38), when keeping the stool form soft helps minimise trauma to the anal canal. Stimulant laxatives The level of evidence for stimulant laxatives is comparable to that for stool softeners. Stimulant laxatives in common use include conjugated anthraquinone derivatives such as senna (sennosides A and B) as well as other agents such as bisacodyl (Bisalax, Dulcolax), and Normacol (a formulation containing both fibre [sterculia] and a peristaltic stimulant [frangula bark]). Stimulant laxatives increase intestinal fluid accumulation when they are metabolised to an active state by bowel flora (conjugated anthraquinone derivatives in particular are cleaved to an active unconjugated state by colonic bacteria), and may also stimulate sensory nerve endings in the colonic mucosal lining. Hence they have both secretagogue and prokinetic effects in the colon. Chronic use of senna-based laxatives can lead to pigmentation of the colonic mucosal lining (melanosis coli). Melanosis coli in itself is a harmless and somewhat reversible condition. However, ongoing use of these agents may lead to tolerance and dependency in the long term, and possibly the condition ‘cathartic colon’ (a rarely seen but severe manifestation of prolonged laxative use characterised by dilation of the large bowel). Hence, regular chronic use of stimulant laxatives is generally discouraged, although they can be useful and cost-effective in the short term. Stimulant laxatives may be especially useful in some older patients, especially if osmotic agents lead to loose stools and hence faecal seepage or incontinence. Osmotic laxatives Use of osmotic laxatives is supported by stronger evidence in the literature. These agents include lactulose and sorbitol (level II evidence) and polyethylene glycol (level I evidence). 36 | Australian Doctor | 19 September 2008 www.australiandoctor.com.au AD_ 0 3 7 _ _ _ SEPT 1 9 _ 0 8 . PDF Pa ge 1 9 / 1 0 / 0 8 , 5 : 0 9 PM Table 3: NHMRC guidelines for a healthy diet* Food Groups Men Cereals 4-12† Women 4-9 4-6 Vegetables 5 5 5-6 Fruit 2 2 4 Dairy products 2 2 2 Lean meat, poultry, fish, nuts, legumes 1 1 1.5 Water >1.5L >1.5L >1.5L ‡ Pregnancy *Number of serves of each food group per day for healthy adults † 4-9 serves for men > 60 years old; 6-12 serves for men 19-60 years old ‡ 4-7 serves for women > 60 years old; 4-9 serves for women 19-60 years old Table 4: Laxatives in common use Group Examples Stool softeners Docusate Stimulants Senna, bisacodyl, frangula bark Osmotic agents Lactulose, sorbitol, polyethylene glycol, magnesium salts Suppositories Glycerine, bisacodyl Enemas Sodium citrate with sorbitol, sodium phosphate Other osmolar laxatives in common use include lowdose polyethylene glycol with electrolytes (Movicol) and magnesium-based agents such as Epsom salts. Both sorbitol and lactulose are non-absorbable sugars that are degraded by colonic bacteria to acidic molecules that increase the acidity and osmolarity of stool, leading to increased fluid in the colon. The increased intraluminal bulk also helps stimulate peristalsis. Polyethylene glycol is a potent hyperosmolar agent that moves a large amount of fluid into the bowel lumen. Magnesium salts also draw fluid into the intestine and may also hasten transit time via an increase in cholecystokinin levels. The usual dosage for the unabsorbed mono- and disaccharides such as lactulose and sorbitol is 10-20mL 1-3 times daily. The standard dosage for magnesium sulphate is 1-2 teaspoons once or twice daily, and for Movicol one sachet 1-3 times daily. Some caution should be given to use of all osmotic agents, as they can lead to a net osmotic influx of water into the intestines, and hence dehydration and electrolyte imbalance. Occasionally osmotic bowel preparations such as large-volume polyethylene glycol (up to 3L) and Picoprep are used for cases of severe constipation but they should be used with extreme caution (especially Picoprep), as these particular agents can cause significant dehydration and electrolyte disturbance. These agents should not be used at all for management of constipation in the elderly or in patients with renal impairment. Higher doses of Movicol (eight sachets dissolved in 1L of water a day) have been used Figure 3: Management of constipation. Stage 1: Practical management tips ■ Exclude organic pathology or contributory medications. Consider colonoscopy if age > 40 and recent onset of symptoms ■ Increase fluid intake (non-caffeinated, non-alcoholic) ■ Increase in dietary fibre intake (up to 30g/day) ■ Fibre supplementation, eg, psyllium husk, sterculia ■ Incorporate regular exercise into daily routine ■ Address depression or stress issues, if present ■ Encourage regular meals and sleeping patterns (eg, avoid missing breakfast) ■ Advice on correct toilet positioning (eg, use of a footstool) ■ Finally, consider use of laxatives (see Stage 2) ■ The best evidence is for use of osmotic laxatives, eg, low-dose polyethylene glycol ■ Stool softeners are a useful adjunct in patients with hard stool ■ Stimulant laxatives can be used in the short term, especially in older patients ■ Enemas or suppositories, depending on distribution of faecal loading ■ If response is poor, consider referral (see Stage 3) Stage 2: Pharmacological therapy Stage 3: Resistant cases Specialist involvement should be considered at this stage Suspected pelvic floor dyssynergia Suspected colonic inertia Anorectal manometry Nuclear medicine and consideration for colonic transit study, biofeedback therapy followed by adjustment of laxatives; may consider colectomy or sacral nerve stimulation Reconsider organic disease Suspected psychological factors See table 2 for review of potential causes and reconsider colonoscopy if not yet done (even if patient’s age is <40) Consider psychological treatments, eg, hypnotherapy in irritable bowel syndrome in severe constipation with faecal impaction. Lubricants Paraffin oil has been used for some time to treat constipation but has several adverse effects such as lipoid pneumonia from aspiration, granulomatous hepatitis from systemic absorption, and fat-soluble vitamin deficiencies. Prokinetic agents Cisapride increases GI motor activity and has been used to treat constipation as well as other motility disorders such as gastroparesis. Its use has now been severely limited because of associations with cardiac arrhythmias. Enemas and suppositories In patients with faecal loading on abdominal X-ray, or when physical examination indicates rectal retention of stool, local suppositories or enemas may be helpful. Enemas provide bulk and www.australiandoctor.com.au volume in the rectum, to stimulate defaecation. Phosphate-based enemas such as Fleet are effective but should be used with caution in patients prone to renal or electrolyte problems. Rectal mucosal damage can occur with enemas but is uncommon. Microlax enemas and glycerine suppositories have a more gentle local effect, acting as stool softeners in the rectum, and glycerine as a 3g suppository also has a local osmotic effect. Bisacodyl suppositories have a stimulant effect on large-bowel mucosa, which manifests itself within 1560 minutes of administration. In cases of severe impaction, manual removal is very occasionally required, but this is often painful and may require some local anaesthetic gel or even sedation or anaesthesia. Combination therapy Many patients require a combination of therapies. For example, patients can benefit from combining both non-pharmacological and pharmacological treatments. Sometimes combinations of laxatives from different classes are also helpful, for example, using a stool softener with an osmotic agent, or using enemas or suppositories on an as-needed basis. To aid compliance, it is also helpful to provide patients with a written list of the dietary, lifestyle and pharmacological interventions recommended, as shown in figure 3. Herbal laxatives Herbal laxatives may contain a combination of fibre (eg, psyllium husk), stimulant laxatives (eg, frangula bark, senna and liquorice), or osmotic agents (eg, magnesium). Patients may be unaware that they are taking stimulant laxatives in their herbal remedies, so use of such over-the-counter remedies should be discussed openly with them, especially as peristaltic stimulants are not recommended for prolonged use. Other agents Serotonergically active drugs such as tegaserod, a 5hydroxytryptamine 4 partial agonist, were used until recently to stimulate peristalsis, leading to improved gastric emptying and colonic transit time. Tegaserod was in particular noted to be useful not only in patients with refractory constipation, but also in those with constipation-predominant IBS, due to its inhibition of visceral hypersensitivity. However, tegaserod has been withdrawn from the market because of cardiac side effects. Another group of agents showing some promise include chloride-channel activators such as lubiprostone. Research is ongoing to find newer, safer agents to treat constipation. When to refer Referral for specialist investigation is suggested when: ■ Colonoscopy is indicated because of suspicion of colorectal malignancy. ■ Anorectal manometry is considered because of symptoms of pelvic floor inco-ordination that may be amenable to biofeedback therapy. ■ Structural lesions such as megacolon or rectocoele are suspected. ■ Chronic intractable constipation is present, affecting quality of life. ■ Diet, lifestyle, and laxative interventions fail, as discussed above. 19 September 2008 | Australian Doctor | 37 AD_ 0 3 8 _ _ _ SEPT 1 9 _ 0 8 . PDF Pa ge 1 9 / 1 1 / 0 8 , 3 : 3 8 PM How to treat – constipation Specialist intervention and the GP’s ongoing role GASTROENTEROLOGISTS or colorectal surgeons will consider whether further investigations such as colonoscopy are required and will review the patient’s progress and treatments to date. In some cases, formulation of a new management plan may be helpful, but more specialised interventions include surgery and biofeedback therapy. Indications for surgery Anal fissures commonly coexist with constipation and will often manifest with intense anal pain on defaecation. Management of constipation will help, but additional therapy with topical nitrates (Rectogesic) may be needed to alleviate pain. Persistent anal fissures can be dealt with by injection of botulinum toxin or by surgical intervention, with division of the anal sphincter. In patients with rectocoeles, the indications to proceed with surgery are unclear, as alleviation of symptoms does not seem to depend on the size of the rectocoele. Women with rectocoeles should be asked if digital pressure on the posterior wall of the vagina during defaecation helps with the passage of stool (in such cases, the rectocoele functions as a redundant reservoir of stool, and surgical removal should improve the defaecation process). Patients with rectocoeles should also be assessed for pelvic floor dyssynergia, as otherwise symptoms of defaecatory dysfunction may recur despite surgery. Subtotal colectomy for severe slow-transit constipation (colonic inertia) is sometimes performed, but only after all other options have been explored. Caution is needed if the patient has significant pain or upper gut dysmotility, as in these cases the response to surgery may be less favourable. Complications of subtotal colectomy with ileorectal anastomosis include small-bowel obstruction in more than one-third of patients, as well as diarrhoea, incontinence and even recurrence of constipation (especially if small-bowel motility is abnormal). Another therapeutic option for colonic inertia, sacral nerve stimulation (already in use for the treatment of faecal incontinence), is currently being performed on a trial basis. Biofeedback therapy In patients with obstructed defaecation resulting from manometryproven pelvic floor inco-ordination, referral for biofeedback therapy is strongly supported in the literature (level I evidence). Biofeedback therapy has been shown to have a mean success rate of 78% in studies for functional constipation and pelvic floor dyssynergia, and is currently being investigated in certain patients with constipation-predominant IBS. A typical biofeedback program within a motility unit at a tertiary referral centre involves: ■ Weekly clinical interviews (eg, over six weeks). ■ Education and dietary advice. ■ Medication adjustments, as appropriate. ■ Advice on correct toileting behaviour and positioning. ■ Abdominal breathing technique. ■ Manometry-based biofeedback to allow anal relaxation and achieve adequate rectal pressure on strain. ■ Rectal sensory retraining. ■ Balloon expulsion retraining. After the biofeedback program, the GP has a crucial role in following up the patient’s symptoms and encouraging adherence to recommendations provided from the program, to achieve lasting improvement in bowel habit and anorectal function. Furthermore, referral to a psychiatrist or psychologist may be helpful for management of coexistent anxiety or depression, and hypnotherapy or cognitive behaviour programs are used in some patients with IBS. Conclusion Constipation is a common problem that can significantly affect the individual’s quality of life. It is mandatory to exclude organic conditions such as colorectal cancer in patients with a change in their symptom pattern or other warning signs. In most instances patients respond to simple management measures, but an increasing range of options is available for management in general practice, with more specialised interventions in severe cases. Reference 1. Mertz H, et al. Physiology of refractory chronic constipation. American Journal of Gastroenterology 1999; 94: 609-15. Online resources ■ ■ ■ Gastroenterological Society of Australia patient leaflet: www.gesa.org.au/leaflets/ constipation.cfm National Digestive Diseases Information Clearinghouse (patient information): http://digestive.niddk.nih. gov/ddiseases/pubs/ constipation MJA Practice Essentials – Paediatrics. 5. Constipation and toileting issues in children: http://mja.com.au/public/issues /182_05_070305/cat10379_ m.html PLEASE REVIEW PRODUCT INFORMATION BEFORE PRESCRIBING. PRODUCT INFORMATION CAN BE FOUND IN THE PRIMARY ADVERTISEMENT IN THIS PUBLICATION. PBS Information: Restricted benefit. For single maintenance and reliever therapy in a patient who experiences frequent asthma symptoms while receiving treatment with oral corticosteroids or inhaled corticosteroids or a combination of an inhaled corticosteroid and a long acting beta-2-agonist (Symbicort 400/12 is not recommended nor PBS subsidised for use in maintenance and reliever therapy). 38 | Australian Doctor | 19 September 2008 www.australiandoctor.com.au AD_039___SEPT19_08 Page 6 11/9/08 3:28 PM Authors’ case studies Constipation with overflow diarrhoea and incontinence A 56-YEAR-old woman was admitted to hospital with a five-month history of diarrhoea with faecal incontinence. She described sudden onset of diarrhoea, initially occurring 10 times a day and up to 25 times a day at its maximum, with associated faecal incontinence. Her background medical history included rheumatoid arthritis and osteoporosis, and a strong family history of colorectal cancer. Her medications included Imodium two tablets three times a day, psyllium husks one teaspoon daily, prednisone 15mg daily, sulfasalazine, hydroxychloroquine, alendronate, paracetamol, ranitidine, vitamin D, Caltrate, glucosamine and fish oil. None of these medications had been started around the onset of the diarrhoea. The patient underwent a series of investigations, including stool cultures with Clostridium difficile toxin; blood tests, including thyroid function, coeliac serology, serum gastrin and vasoactive intestinal peptide levels; as well Figure 4. Left: Pre-treatment abdominal X-ray with faecal loading. Right: Post-treatment X-ray showing clearance of faecal loading. as colonoscopy with random colonic biopsies, with no cause for diarrhoea found. She was prescribed courses of metronidazole and tinidazole, in case of undetected protozoal infection, but these made no impact on her diarrhoea. She also underwent a small-bowel series, which showed prolonged transit, and anorectal manometry, which showed low anal squeeze pressures and rectal hyposensitiv- ity. A subsequent abdominal X-ray revealed extensive faecal loading (figure 4). A diagnosis of constipation with overflow diarrhoea and incontinence was made, and the patient was treated with regular Movicol (one sachet bd) and Epsom salts (one teaspoon bd), with a short course of Coloxyl with Senna and Fleet enemas daily to clean out the bowel. She was also advised to stop Imodium and increase her intake of fluids to 3L a day. She subsequently underwent a course of anorectal biofeedback therapy for the symptom of incontinence, to increase her anal sphincter squeeze pressures and improve rectal sensitivity. She noted a significant improvement in her bowel habit within a few weeks and has maintained regular bowel movements twice daily. Constipation-predominant IBS A 47-year-old man presented with a 20-year history of severe constipation associated with abdominal pain and bloating, which had begun after a bout of infective gastroenteritis. He described difficulty with defaecation, feeling as though his anal passage was “shut down”, excessive straining, and excessive time spent on the toilet. His toileting routine occupied 7-8 hours a day and he had developed a dependence on a modified squat-toilet system that he had set up at home, which was a major imposition on his quality of life. He had not travelled away from home in 20 years, given this need to use his own toilet system. Over the preceding 10 years, he had sought multiple medical opinions, and a colonic transit study had shown slow transit, and a defaecating proctogram had shown extremely poor emptying. Because of predominant symptoms of constipation with sensations of anal blockage and incomplete emptying, he was referred for anorectal manometry. This revealed elevated resting anal sphincter pressure and rectal hypersensitivity, as well as extremely high rectal pressure on strain, with paradoxical anal contraction on strain. The findings were consistent with his clinical diagnosis of constipation-predominant IBS (probably post-infective) with concurrent pelvic-floor dyssynergia. The patient underwent a six-visit course of biofeedback therapy, including the following components: ■ Advice on correct toileting position and behaviour. ■ Improvement in fibre and water intake. ■ Abdominal breathing technique. ■ Manometry-based therapy to allow anal relaxation with strain. After treatment he noted a significant improvement in his bowel habit and abdominal bloating. In particular, he had reduced his toileting time to three hours a day and had even managed a short holiday away from home. Now you can manage what many asthma ‡ patients worry about * with ONE inhaler. † *Symbicort Maintenance And Reliever Therapy (Symbicort SMART) in one inhaler. Only Symbicort 100/6 and 200/6 doses are approved for use in patients indicated for the SMART regimen.4 †Symbicort® SMART™ has been shown to reduce the number of severe exacerbations with a reduced inhaled corticosteroid + oral corticosteroid vs. fixed-dose combination therapy + short-acting β2-agonist.1-4 In the event of an asthma emergency, patients should follow their asthma action plan, as directed by the doctor. ‡Despite taking regular asthma medication, 49% of patients still feared a serious exacerbation.5 54% of patients were concerned about taking too much medication when they felt well.5 References: 1. Kuna P et al. Int J Clin Prac, 2007; 61(5): 725–736. 2. Bousquet J et al. Respir Med, 2007; 101: 2437–2446. 3. Vogelmeier C et al. Eur Respir J, 2005; 26: 819–828. 4. Symbicort Approved Product Information, July 2006. 5. Partridge MR et al. BMC Pulm Med, 2006; 6: 13. Symbicort® and Turbuhaler® are registered trademarks of the AstraZeneca group of companies. Symbicort SMART™ is a trademark of the AstraZeneca group of companies. Registered user AstraZeneca Pty Ltd. ABN 54 009 682 311. Alma Road, North Ryde, NSW 2113. AZAE0609 H&T AZSY0839/AD www.australiandoctor.com.au 19 September 2008 | Australian Doctor | 39 AD_ 0 4 0 _ _ _ SEPT 1 9 _ 0 8 . PDF Pa ge 1 9 / 1 1 / 0 8 , 1 1 : 1 3 AM How to treat – constipation GP’s contribution Case study DR MATILDA METLEDGE Sydney, NSW MR B, 35, underwent major back surgery four months ago. During his hospital stay he was required to lie flat for three days and developed severe constipation with intense abdominal pain. He was finally (after another two days) treated with an enema, with good result. Since discharge he has never returned to his normal bowel habit of every 1-2 days (now every 3-6 days) and feels constantly bloated and full. His abdominal X-ray showed faecal loading, and a repeat enema was given a few weeks ago, again with good effect. He remains on low-dose Endone (5mg daily) along with four Coloxyl with Senna bd, which he states “does nothing”. He now returns with the same bloating and fullness. Questions for the authors For patients on long-term opiates for chronic pain, what would your advice be in regard to pharmacological therapy for constipation? If patients are taking opiates for the long term, and need treatment for constipation other than correction of fibre and water intake, often an osmotic agent will be required, as these are effective and the dose can be titrated. How to Treat Quiz Constipation — 19 September 2008 1. Which TWO statements about the epidemiology of constipation are correct? a) The prevalence of constipation in the general population is 15-20% b) In patients under 50, men are twice as likely to be affected as women c) Groups more likely to be affected by constipation include the elderly, children and pregnant women d) A NSW survey showed most patients with constipation sought help for their condition 2. Which TWO statements about causes of constipation are correct? a) It is very important to consider mechanical obstruction from colorectal malignancy as a cause of constipation b) Metabolic disorders that may be associated with constipation include diabetes mellitus and hypercalcaemia c) There are no diagnostic criteria for functional constipation; rather, this is a diagnosis of exclusion d) Pelvic floor dyssynergia causes urinary difficulties but not constipation 3. Kim, 38, has suffered from constipation since her early teens but has not sought help in managing it before. Which THREE statements about assessing patients with constipation are correct? a) A careful review of medication needs to be undertaken, including over-the-counter agents such as calcium and iron supplements b) History should include enquiry about symptoms that may indicate pelvic floor dysfunction c) Enquiring about a family history of bowel disorders is not important in the history d) Digital rectal examination is an essential component of the physical examination 4. You take a full history from Kim. Dietary history reveals a low-fibre diet. She has no warning symptoms for malignancy, and the relevant physical examination is normal. Which TWO statements about investigating constipation are correct? a) Initial blood tests may include FBC, serum calcium, blood glucose level and thyroid function testing b) There is no role for a plain abdominal X-ray in patients with constipation c) A colonoscopy should be considered in all patients with warning signs for malignancy d) There is no role for a barium enema in patients with constipation 5. Which TWO statements about additional investigations are correct? a) Defaecography can be useful for detecting a rectocoele with stool retention b) Patients unable to expel the balloon on a balloon expulsion test within 15 seconds are highly likely to have pelvic floor dyssynergia c) A nuclear medicine colonic transit study is normal if there is significant residual tracer by day 5 d) Hirschsprung’s disease can be largely excluded by anorectal manometry Some caution needs to be given about long-term stimulant laxatives, as discussed earlier (page 36). If stools remain hard despite correction of fluid and fibre intake, a stool softener can be added in. What dose of Coloxyl is reasonable to commence with in this type of case, and how high can the dose be titrated before we can state treatment failure? Coloxyl (without senna) is merely a stool softener and its efficacy is mild. I usually prefer to optimise the stool form with water and fibre first, but if I do use Coloxyl I don’t go above two or three tablets twice daily. Most patients require much encouragement to achieve even the NHMRC guidelines for water and fibre intake for the normal individual. If using Coloxyl with Senna in the short term, I usually don’t go above two tablets twice daily. Is it best to use multiple agents in low doses or to escalate a single drug to the maximum dose in resistant uncomplicated constipation? I do not see the point in using more than one agent from the same class of laxatives. However, I sometimes use combination therapy with, say, an osmotic agent, supplemental fibre and prn enemas, suppositories or possibly stimulant laxatives. In all situations I attempt to normalise the form of the stool. General question for the authors Could you extrapolate on ‘correct toileting behaviour and positioning’, besides footstools and morning attempts? Some patients have quite abnormal toileting behaviours and we try to modify this. For example some patients spend more than 30 minutes per attempt at toileting, some are making multiple attempts to defaecate per day, some have excess straining, some attempt to defaecate standing or sit in a very contorted position and some patients are digitally disimpacting. INSTRUCTIONS Complete this quiz online and fill in the GP evaluation form to earn 2 CPD or PDP points. We no longer accept quizzes by post or fax. The mark required to obtain points is 80%. Please note that some questions have more than one correct answer. ONLINE ONLY www.australiandoctor.com.au/cpd/ for immediate feedback 6. You arrange for Kim to have some initial blood tests, the results of which are normal. You also discuss the current recommendations for fibre intake with her. Which TWO statements are correct? a) NHMRC guidelines recommend intake of 15g of fibre a day for women, and 20g a day for men b) NHMRC recommendations are two serves of fruit and five serves of vegetables daily c) NHMRC recommendations for daily intake of cereal products are 2-4 serves for men and 2-3 serves for women d) Fibre intake should be combined with a minimum of 1.5L of non-caffeinated and non-alcoholic fluids a day 7. You also discuss with Kim the use of a fibre supplement, such as psyllium. Which THREE statements about the management of constipation are correct? a) The benefits of supplemental fibre will be evident to the patient within 1-2 days b) Regular exercise is generally recommended in the management of constipation c) Symptoms of anxiety or depression should be addressed if present d) Patients should be encouraged to avoid missing breakfast 8. Kim reveals that she occasionally takes Coloxyl with Senna when her constipation is particularly troublesome. Which TWO statements are correct? a) There is good evidence (level I) to support the use of stool softeners b) Regular chronic use of stimulant laxatives is generally discouraged in young patients c) Stimulant laxatives can be used in the short term, especially in older patients d) There is no benefit from combining laxatives from different classes 9. Which TWO statements about pharmacological therapy for constipation are correct? a) There is little evidence to support the use of osmotic laxatives b) Some caution should be given to use of all osmotic agents, as they can lead to dehydration and electrolyte imbalance c) Paraffin oil has a benign side-effect profile d) Phosphate-based enemas should be used with caution in patients prone to renal or electrolyte problems 10. Which THREE statements about specialist management of constipation are correct? a) In patients with rectocoeles there are clear indications as to when to proceed with surgery b) Subtotal colectomy for severe slow-transit constipation is sometimes performed, but only after all other options have been explored c) There is good evidence to support biofeedback therapy for patients with obstructed defaecation due to manometryproven pelvic floor inco-ordination d) If there are suspected psychological factors, referral to a psychiatrist or psychologist may be helpful CPD QUIZ UPDATE The RACGP now requires that a brief GP evaluation form be completed with every quiz to obtain category 2 CPD or PDP points for the 2008-10 triennium. You can complete this online along with the quiz at www.australiandoctor.com.au. Because this is a requirement, we are no longer able to accept the quiz by post or fax. However, we have included the quiz questions here for those who like to prepare the answers before completing the quiz online. HOW TO TREAT Editor: Dr Wendy Morgan Co-ordinator: Julian McAllan Quiz: Dr Wendy Morgan NEXT WEEK Panic attacks visit with a shocking suddenness, alarming severity and terrifying portent. The next How to Treat will help explain what causes panic attacks to persist — one of the most important factors in understanding how to treat them. The author is Dr Lisa A Lampe, senior lecturer, discipline of psychological medicine, University of Sydney; consultant psychiatrist, CADE clinic, Royal North Shore Hospital, St Leonards; and senior staff specialist (academic), Hornsby Ku-ring-gai Health Service, Hornsby, NSW. 40 | Australian Doctor | 19 September 2008 www.australiandoctor.com.au