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Secondary chronic intestinal pseudo-obstruction is managed by treating the underlying condition.
There is no cure for primary chronic intestinal pseudo-obstruction. It is important that nutrition and hydration is maintained, and pain relief is given. Drugs that increase the propulsive force of the intestines have been tried, as have different types of surgery.
Prucalopride, pyridostigmine, metoclopramide, cisapride, and erythromycin may be used, but they have not been shown to have great efficacy. In such cases, treatment is aimed at managing the complications. Linaclotide is a new drug that received approval from Food and Drug Administration in August 2012 and looks promising in the treatment of chronic intestinal pseudo-obstruction, gastroparesis and inertia coli.
Intestinal stasis, which may lead to bacterial overgrowth and subsequently, diarrhea or malabsorption, is treated with antibiotics.
Nutritional deficiencies are treated by encouraging patients to avoid food high in fat and fibre, which are harder to digest and increase abdominal distention and discomfort, and have small, frequent meals (5–6 per day), focusing on liquids and soft food. Reducing intake of poorly absorbed sugar alcohols may be of benefit. Referral to an accredited dietitian is recommended. If dietary changes are unsuccessful in meeting nutritional requirements and stemming weight loss, enteral nutrition is used. Many patients eventually require parenteral nutrition.
Total parenteral nutrition (TPN) is a form of long-term nutritional treatment needed for patients that have severe pseudoobstruction. After a period of no improvement of intestinal function or motility the decision to start TPN will be made, and the surgical procedure to add a long-term, more permanent IV to administer TPN will occur. Types of IV catheters to be placed will be a PICC line or central line which include mediports, Broviac, or Hickman lines depending on how long the physicians believe the patient will require TPN. Patients that are deemed TPN dependent will require constant checkups to monitor the catheter is working properly, check liver enzyme levels and look for signs of blood infections, as catheter blockage, liver damage, and infections of catheters are the main complications associated with long term TPN use and can result in sepsis and/or additional surgeries if not properly monitored. TPN nutritional feeds are given over a period of several hours to all day infusions, and are a mixture of all the vitamins, minerals, and calories similar to what one would get eating orally daily as well as any other specific nutritional needs the patient has at the moment. TPN format is typically changed depending on loss/gain of weight and bloodwork results, and is specially formulated to meet each individual patient's needs.
Use of octreotide has been described.
Cannabis has long been known to limit or prevent nausea and vomiting from a variety of causes. This has led to extensive investigations that have revealed an important role for cannabinoids and their receptors in the regulation of nausea and emesis. With the discovery of the endocannabinoid system, novel ways to regulate both nausea and vomiting have been discovered that involve the production of endogenous cannabinoids acting centrally. The plant cannabis has been used in clinics for centuries, and has been known to be beneficial in a variety of gastrointestinal diseases, such as emesis, diarrhea, inflammatory bowel disease and intestinal pain. Moreover, modulation of the endogenous cannabinoid system in the gastrointestinal tract may provide a useful therapeutic target for gastrointestinal disorders. While some GI disorders may be controlled by diet and pharmaceutical medications, others are poorly moderated by conventional treatments. Symptoms of GI disorders often include cramping, abdominal pain, inflammation of the lining of the large and/or small intestine, chronic diarrhea, rectal bleeding and weight loss. Patients with these disorders frequently report using cannabis therapeutically.
In a 2012 animal study, cannabichromene was shown to normalize gastrointestinal hypermotility without reducing the transit time. The study notes that this result is of potential clinical interest, as the only drugs available for intestinal dysmotility are often associated with constipation.
Traditionally, nothing by mouth was considered to be mandatory in all cases, but gentle feeding by enteral feeding tube may help to restore motility by triggering the gut's normal feedback signals, so this is the recommended management initially. When the patient has severe, persistent signs that motility is completely disrupted, nasogastric suction and parenteral nutrition may be required until passage is restored. In such cases, continuing aggressive enteral feeding causes a risk of perforating the gut.
Several options are available in the case of paralytic ileus. Most treatment is supportive. If caused by medication, the offending agent is discontinued or reduced. Bowel movements may be stimulated by prescribing lactulose, erythromycin or, in severe cases that are thought to have a neurological component (such as Ogilvie's syndrome), neostigmine. There is also evidence from a systematic review of randomized controlled trials that chewing gum, as a form of 'sham feeding', may stimulate gastrointestinal motility in the post-operative period and reduce the duration of postoperative ileus.
If possible the underlying cause is corrected (e.g. replace electrolytes).
The "treat empirically" route also has its difficulties, which have all come under wide debate and study. Recommendations are varied but seem to find some common ground around the notion that treatment should be individualized to the specific circumstances under which a patient has developed BLS since these circumstances affect the complex microbial make up of the affected bowel.
Tetracyclines have been the mainstay of treatment for BLS, but recent studies have concluded Rifaximin to be very effective in the treatment of BLS. One study by Di Stefano et al., however, concluded Metronidazole to be more effective than Rifaximin in the treatment of BLS.
Although it would seem to be the better way to go in terms of management, there has been recent criticism on the need for such testing because of reliability issues. However, it must be stated that there are options such as the glucose breath test and jejunal aspiration the explanations of which are beyond the scope of this current article.
In addition to fluid support, impactions are often treated with intestinal lubricants and laxatives to help move the obstruction along. Mineral oil is the most commonly used lubricant for large colon impactions, and is administered via nasogastric tube, up to 4 liters once or twice daily. It helps coat the intestine, but is not very effective for severe impactions or sand colic since it may simply bypass the obstruction. Mineral oil has the added benefit of crudely measuring GI transit time, a process which normally takes around 18 hours, since it is obvious when it is passed. The detergent dioctyl sodium sulfosuccinate (DDS) is also commonly given in oral fluids. It is more effective in softening an impaction than mineral oil, and helps stimulate intestinal motility, but can inhibit fluid absorption from the intestine and is potentially toxic so is only given in small amounts, two separate times 48 hours apart. Epsom salts are also useful for impactions, since they act both as an osmotic agent, to increase fluid in the GI tract, and as a laxative, but do run the risk of dehydration and diarrhea. Strong laxatives are not recommended for treating impactions.
Possible treatments include:
- In stable cases, use of laxatives and bulking agents, as well as modifications in diet and stool habits are effective.
- Corticosteroids and other anti-inflammatory medication is used in toxic megacolon.
- Antibiotics are used for bacterial infections such as oral vancomycin for "Clostridium difficile"
- Disimpaction of feces and decompression using anorectal and nasogastric tubes.
- When megacolon worsens and the conservative measures fail to restore transit, surgery may be necessary.
- Bethanechol can also be used to treat megacolon by means of its direct cholinergic action and its stimulation of muscarinic receptors which bring about a parasympathetic like effect.
There are several surgical approaches to treat megacolon, such as a colectomy (removal of the entire colon) with ileorectal anastomosis (ligation of the remaining ileum and rectum segments), or a total proctocolectomy (removal of colon, sigmoid and rectum) followed by ileostomy or followed by ileoanal anastomosis.
Fluids are commonly given, either orally by nasogastric tube or by intravenous catheter, to restore proper hydration and electrolyte balance. In cases of strangulating obstruction or enteritis, the intestine will have decreased absorption and increased secretion of fluid into the intestinal lumen, making oral fluids ineffective and possibly dangerous if they cause gastric distention and rupture. This process of secretion into the intestinal lumen leads to dehydration, and these horse require large amounts of IV fluids to prevent hypotension and subsequent cardiovascular collapse. Fluid rates are calculated by adding the fluid lost during each collection of gastric reflux to the daily maintenance requirement of the horse. Due to the fact that horses absorb water in the cecum and colon, the IV fluid requirement of horses with simple obstruction is dependent on the location of the obstruction. Those that are obstructed further distally, such as at the pelvic flexure, are able to absorb more oral fluid than those obstructed in the small intestine, and therefore require less IV fluid support. Impactions are usually managed with fluids for 3–5 days before surgery is considered. Fluids are given based on results of the physical examination, such as mucous membrane quality, PCV, and electrolyte levels. Horses in circulatory shock, such as those suffering from endotoxemia, require very high rates of IV fluid administration. Oral fluids via nasogastric tube are often given in the case of impactions to help lubricate the obstruction. Oral fluids should not be given if significant amounts of nasogastric reflux are obtained. Access to food and water will often be denied to allow careful monitoring and administration of what is taken in by the horse.
Proximal enteritis usually is managed medically. This includes nasogastric intubation every 1–2 hours to relieve gastric pressure secondary to reflux, which often produces to 2–10 L, as well as aggressive fluid support to maintain hydration and correct electrolyte imbalances. Maintaining hydration in these patients can be very challenging. In some cases, fluid support may actually increase reflux production, due to the decreased intravascular oncotic pressure from low total protein and albumin levels, leading to loss of much of these IV fluids into the intestinal lumen. These horses will often display dependent edema (edema that collects in locations based on gravity). Colloids such as plasma or Hetastarch may be needed to improve intravascular oncotic pressure, although they can be cost prohibitive for many owners. Reflux levels are monitored closely to help evaluate fluid losses, and horses recovering from DPJ show improved hydration with decreased reflux production and improved attitude.
Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used for pain relief, reduction of inflammation, and for their anti-endotoxin effects, but care must be taken since they may produce gastrointestinal ulceration and damage the kidneys. Due to a suspected link to "Clostridial" infection, anti-microbials are often administered, usually penicillin or metronidazole. Aminoglycosides should be used with extreme caution due to the risk of nephrotoxicosis (damage to the kidney). The mucosa of the intestines is damaged with DPJ, often resulting in absorption of endotoxin and risking laminitis, so therapy to combat and treat endotoxemia is often employed. This includes treatment with drugs that counteract endotoxin such as Polymyxin B and Bio-Sponge, fluid support, and laminitis prevention such as icing of the feet. Prokinetic drugs such as lidocaine, erythromycin, metoclopramide, and bethanechol are often used to treat the ileus associated with the disease.
Horses are withheld food until reflux returns to less than 1–2 L of production every 4 hours, and gut sounds return, often requiring 3–7 days of therapy. Parenteral nutrition is often provided to horses that are withheld feed for greater than 3–4 days. It is suspected to improve healing and shorten the duration of the illness, since horses often become cachexic due to the protein losing enteropathy associated with this disease.
Surgery may need to be performed to rule out colic with similar presenting signs such as obstruction or strangulation, and in cases that are long-standing (> 7 days) to perform a resection and anastomosis of the diseased bowel. However, some horses have recovered with long-term medical support (up to 20 days).
Many people with diverticulosis have minimal to no symptoms, and do not require any specific treatment. Colonic stimulants should be avoided. Treatments, like some colon cleansers, that cause hard stools, constipation, and straining, are not recommended.
Treatment is directed largely towards management of underlying cause:
- Replacement of nutrients, electrolytes and fluid may be necessary. In severe deficiency, hospital admission may be required for nutritional support and detailed advice from dietitians. Use of enteral nutrition by naso-gastric or other feeding tubes may be able to provide sufficient nutritional supplementation. Tube placement may also be done by percutaneous endoscopic gastrostomy, or surgical jejunostomy. In patients whose intestinal absorptive surface is severely limited from disease or surgery, long term total parenteral nutrition may be needed.
- Pancreatic enzymes are supplemented orally in pancreatic insufficiency.
- Dietary modification is important in some conditions:
- Gluten-free diet in coeliac disease.
- Lactose avoidance in lactose intolerance.
- Antibiotic therapy to treat Small Bowel Bacterial overgrowth.
- Cholestyramine or other bile acid sequestrants will help reducing diarrhoea in bile acid malabsorption.
Surgical intervention is nearly always required in form of exploratory laparotomy and closure of perforation with peritoneal wash. Occasionally they may be managed laparoscopically.
Conservative treatment including intravenous fluids, antibiotics, nasogastric aspiration and bowel rest is indicated only if the person is nontoxic and clinically stable.
In the management of small bowel obstructions, a commonly quoted surgical aphorism is: "never let the sun rise or set on small-bowel obstruction" because about 5.5% of small bowel obstructions are ultimately fatal if treatment is delayed. However improvements in radiological imaging of small bowel obstructions allow for confident distinction between simple obstructions, that can be treated conservatively, and obstructions that are surgical emergencies (volvulus, closed-loop obstructions, ischemic bowel, incarcerated hernias, etc.).
A small flexible tube (nasogastric tube) may be inserted through the nose into the stomach to help decompress the dilated bowel. This tube is uncomfortable but does relieve the abdominal cramps, distention, and vomiting. Intravenous therapy is utilized and the urine output is monitored with a catheter in the bladder.
Most people with SBO are initially managed conservatively because in many cases, the bowel will open up. Some adhesions loosen up and the obstruction resolves. However, when conservative management is undertaken, the patient is examined several times a day, and X-ray images are obtained to ensure that the individual is not getting clinically worse.
Conservative treatment involves insertion of a nasogastric tube, correction of dehydration and electrolyte abnormalities. Opioid pain relievers may be used for patients with severe pain. Antiemetics may be administered if the patient is vomiting. Adhesive obstructions often settle without surgery. If the obstruction is complete a surgery is usually required.
Most patients do improve with conservative care in 2–5 days. However, on some occasions, the cause of obstruction may be a cancer and in such cases, surgery is the only treatment. These individuals undergo surgery where the cause of SBO is removed. Individuals who have bowel resection or lysis of adhesions usually stay in the hospital a few more days until they are able to eat and walk.
Small bowel obstruction caused by Crohn's disease, peritoneal carcinomatosis, sclerosing peritonitis, radiation enteritis, and postpartum bowel obstruction are typically treated conservatively, i.e. without surgery.
It usually resolves with conservative therapy stopping oral ingestions, i.e. nil per os and a nasogastric tube, but may require colonoscopic decompression which is successful in 70% of the cases. A study published in the "New England Journal of Medicine" showed that neostigmine is a potent pharmacological way of decompressing the colon. According to the American Society for Gastrointestinal Endoscopy (ASGE), it should be considered prior to colonoscopic decompression. The use of neostigmine is not without risk since it can induce bradyarrhythmia and bronchospasms. Therefore, atropine should be within immediate reach when this therapy is used.
Some causes of bowel obstruction may resolve spontaneously; many require operative treatment. In adults, frequently the surgical intervention and the treatment of the causative lesion are required. In malignant large bowel obstruction, endoscopically placed self-expanding metal stents may be used to temporarily relieve the obstruction as a bridge to surgery, or as palliation. Diagnosis of the type of bowel obstruction is normally conducted through initial plain radiograph of the abdomen, luminal contrast studies, computed tomography scan, or ultrasonography prior to determining the best type of treatment.
Complicated diverticulosis requires treatment of the complication. These complications are often grouped under a single diagnosis of diverticulitis and require skilled medical care of the infection, bleeding and perforation which may include intensive antibiotic treatment, intravenous fluids and surgery. Complications are more common in patients who are taking NSAIDs or aspirin. As diverticulosis occurs in an older population such complications are serious events.
Differentiation of DIOS from constipation is generally performed by unit specializing in the treatment of cystic fibrosis. Adequate hydration and an aggressive regimen of laxatives are essential for treatment and prevention of DIOS. Osmotic laxatives such as polyethylene glycol are preferred. Individuals prone to DIOS tend to be at risk for repeated episodes and often require maintenance therapy with pancreatic enzyme replacement, hydration and laxatives (if the symptoms are also mild).
Oral contrast instillation into the colon/ileum under radiological control has been found to reduce the need for surgical intervention.
The condition is not usually immediately life-threatening. The intussusception can be treated with either a barium or water-soluble contrast enema or an air-contrast enema, which both confirms the diagnosis of intussusception, and in most cases successfully reduces it. The success rate is over 80%. However, approximately 5–10% of these recur within 24 hours.
Cases where it cannot be reduced by an enema or the intestine is damaged require surgical reduction. In a surgical reduction, the surgeon opens the abdomen and manually squeezes (rather than pulls) the part that has telescoped. If the surgeon cannot successfully reduce it, or the bowel is damaged, they resect the affected section. More often, the intussusception can be reduced by laparoscopy, pulling the segments of intestine apart with forceps.
Treatment for sigmoid volvulus may include sigmoidoscopy. If the mucosa of the sigmoid looks normal and pink, place a rectal tube for decompression, correct any fluid, electrolyte, cardiac, renal or pulmonary abnormalities and then take the person to the operating room for repair. If surgery is not performed, there is a high rate of recurrence.
For people with signs of sepsis or an abdominal catastrophe, immediate surgery and resection is advised.
Intussusception may become a medical emergency if not treated early, as it eventually causes death if not reduced. In developing countries where medical hospitals are not easily accessible, especially when other problems complicate the intussusception, death becomes almost inevitable. When intussusception or any other severe medical problem is suspected, the person must be taken to a hospital immediately.
The outlook for intussusception is excellent when treated quickly, but when untreated it can lead to death within two to five days. It requires fast treatment, because the longer the intestine segment is prolapsed the longer it goes without bloodflow, and the less effective a non-surgical reduction is. Prolonged intussusception also increases the likelihood of bowel ischemia and necrosis, requiring surgical resection.
In people presenting with symptoms compatible with radiation enteropathy, the initial step is to identify what is responsible for causing the symptoms. Management is best with a multidisciplinary team including gastroenterologists, nurses, dietitians, surgeons and others.
Medical treatments include the use of hyperbaric oxygen which has beneficial effects in radiation proctitis or anal damage. Nutritional therapies include treatments directed at specific malabsorptive disorders such as low fat diets and vitamin B12 or vitamin D supplements, together with bile acid sequestrants for bile acid diarrhea and possibly antibiotics for small intestinal bacterial overgrowth. Probiotics have all been suggested as another therapeutic avenue.
Endoscopic therapies including argon plasma coagulation have been used for bleeding telangiectasia in radiation proctitis and at other intestinal sites, although there is a rick of perforation. Sucralfate enemas look promising in proctitis.
Surgical treatment may be needed for intestinal obstruction, fistulae, or perforation, which can happen in more severe cases. These can be fatal if patients present as an emergency, but with improved radiotherapy techniques are now less common.
Optimal treatment usually produces significant improvements in quality of life.
Prevention of radiation injury to the small bowel is a key aim of techniques such as brachytherapy, field size, multiple field arrangements, conformal radiotherapy techniques and intensity-modulated radiotherapy. Medications including ACE inhibitors, statins and probiotics have also been studied and reviewed.
Treatment consists primarily of supportive care including providing bowel rest by stopping enteral feeds, gastric decompression with intermittent suction, fluid repletion to correct electrolyte abnormalities and third-space losses, support for blood pressure, parenteral nutrition, and prompt antibiotic therapy. Monitoring is clinical, although serial supine and left lateral decubitus abdominal x-rays should be performed every six hours. Where the disease is not halted through medical treatment alone, or when the bowel perforates, immediate emergency surgery to resect the dead bowel is generally required, although abdominal drains may be placed in very unstable infants as a temporizing measure. Surgery may require a colostomy, which may be able to be reversed at a later time. Some children may suffer from short bowel syndrome if extensive portions of the bowel had to be removed.
Distal or sigmoid, fecalomas can often be disimpacted digitally or by a catheter which carries a flow of disimpaction fluid (water or other solvent or lubricant). Surgical intervention in the form of sigmoid colectomy or proctocolectomy and ileostomy may be required only when all conservative measures of evacuation fail.
Corticosteroids are the mainstay of therapy with a 90% response rate in some studies. Appropriate duration of steroid treatment is unknown and relapse often necessitates long term treatment. Various steroid sparing agents e.g. sodium cromoglycate (a stabilizer of mast cell membranes), ketotifen (an antihistamine), and montelukast (a selective, competitive leukotriene receptor antagonist) have been proposed, centering on an allergic hypothesis, with mixed results. An elimination diet may be successful if a limited number of food allergies are identified.