Clinical presentation of intestinal pseudoobstruction is usually with abdominal distension, constipation, and episodic vomiting. In more severe cases, the intestinal tract fails to function from birth and there is total intestinal failure with bile-stained vomiting (1). Children with hollow visceral myopathy may present with urinary retention. Disorders such as pyloric stenosis and malrotation are more common than in the general population, and may be the presenting problem (2).
The main aim of treatment is to improve the underlying disease to enable normal gastrointestinal function. Unfortunately, in the most severe cases, effective gastrointestinal function cannot be achieved, and intravenous feeding is required to restore and maintain a good nutritional state (1).
This article describes management of the gastrointestinal tract and the use of intravenous feeding and associated problems, along with a review of the long-term outcome of the most severely affected children with chronic, severe intestinal failure.
MANAGEMENT OF THE GI TRACT
The aims of treatment are to restore hydration and nutrition, relieve symptoms, and suppress bacterial overgrowth. Symptoms usually vary in severity from day to day and week to week, from severe problems to periods when the intestine functions normally. In most cases, there is no obvious reason for relapse or remission other than the worsening of symptoms with intercurrent infections and poor nutritional state.
The main aims of treatment are to reduce the problems of fluid loss and bacterial overgrowth in the poorly motile intestine. Fluid loss is easily underestimated because pooling may occur in large dilated loops of intestine before excessive intestinal losses are excreted. Fluid-balance assessment is made more difficult because the child does not lose weight when fluid is lost into the intestinal lumen but not eliminated. Weight loss cannot be relied on to indicate dehydration. Increased abdominal distension may be the only sign of fluid shift from the circulation to the intestinal lumen. The child needs to be carefully assessed clinically, and examined for signs of dehydration. Urinary output should be closely monitored. Measurement of urinary sodium is probably the most helpful biochemical marker. A large volume of fluid replacement may be required. However, it is essential to closely monitor input, output, and state of hydration because the intestine may suddenly “switch off” fluid loss and the child can rapidly become fluid overloaded.
Treatment of Intestinal Motility
Initial treatment of intestinal motility is to attempt to improve peristalsis medically, and if that fails, to consider surgical management as well. Normalisation of intestinal propulsion with prokinetic agents should always be attempted. These agents include erythromycin, cisapride, and domperidone. Unfortunately, in the more severe cases there may be little or no response. Surgical shortening of the bowel may help these patients. When the bowel length is reduced, the poor neuromuscular ability may be sufficiently active to enable effective peristalsis. Decompression stomas such as ileostomy or jejunostomy formation should be considered in all children with persistent intestinal failure (2).
Treatment of Other Intestinal Disorders
A major problem in intestinal pseudoobstruction is bacterial overgrowth in fluid that is pooling in poorly motile, dilated loops of bowel. Excessive bacteria exacerbate symptoms of increased gaseous distension, and probably contribute to intestinal mucosal inflammation. Overgrowth can be diagnosed by detecting bacterial organic acid metabolites in urine, by hydrogen breath test or culture of faeces, or intestinal aspirates. Appropriate antibiotic treatment can alleviate symptoms, including abdominal pain. A rotation of at least 2 antibiotics is commonly used, with 1- or 2-week treatment periods alternating with periods of no treatment. However, in practice in the more severe cases, the effects are short-lived, and with subsequent courses the benefits are fewer. The author is not convinced of any benefit from probiotics in this group of patients. It is highly likely that a high dose would be needed if any effect were to be seen in children with such a large intestinal capacity.
Intestinal mucosal inflammation may occur in intestinal obstruction. Upper and lower intestinal endoscopy with biopsies should be performed because mucosal inflammation may contribute to symptoms, with deterioration in intestinal function as well as worsening of abdominal pain and gaseous distension. Appropriate treatment of the inflammation can improve intestinal function and reduce symptoms. Bacterial overgrowth may contribute to the inflammation. Some patients appear to have an autoimmune component to their pseudoobstruction that also predisposes them to mucosal inflammation. These cases have benefitted from immunosuppressive treatment. Unfortunately, however, improvement can be short-lived.
Severe abdominal pain is not usually a feature of classic neuromuscular pseudoobstruction. When it does occur, a possible mechanical obstruction should be considered. Mechanical obstruction is more common than in the normal intestine because most children with severe pseudoobstruction will have undergone intestinal surgery at some stage. Because the intestine is less mobile than usual, postoperative recovery is delayed, intestinal stasis is prolonged, and adhesions are more likely to develop. Adhesion-associated obstruction is usually best dealt with conservatively.
ACHIEVING AND MAINTAINING A GOOD NUTRITIONAL STATE
In common with intestinal failure due to any aetiology, the main aim is feeding via the GI tract. The texture of food is important because there is poor gastric and peristaltic activity. Bite-dissolvable and pureed foods may be tolerated best. If puree is not tolerated, then liquid enteral feeds should be tried. If gastric emptying is poor, then an artificial feeding device that bypasses the stomach may improve absorption. When the intestine continues to fail to absorb sufficient fluid and nutrients to maintain a good nutritional state and enable growth, intravenous feeding is required. To deliver adequate nutrition, a central venous catheter should be inserted. In a child who is likely to have a long-term need for intravenous nutrition, the catheter should be placed under radiological control because this method is less likely to damage the vein. The most common complication of central venous catheter use is septicaemia. Using a single-lumen rather than a double-lumen catheter, dedicating the line for the use of parenteral fluids only, and limiting the frequency and number of people accessing the line, reduces episodes of septicaemia. Sepsis is reduced even further when the child is cared for at home by 2 parents who have been formally trained in the aseptic use of the line.
The nutrition should be precisely formulated to meet the needs of the child. A standard bag would usually be too diluted and not contain sufficient electrolytes, unless the child is able to absorb a significant amount enterally as well.
Children with chronic severe intestinal failure have the best chance of a good quality of life if discharged home on parenteral nutrition, provided certain criteria are fulfilled. The child needs to be able to cope with 12 hours off parenteral nutrition and to have satisfactory home facilities such as space for an extra refrigerator, running water on the same level as the child's bedroom, and a landline telephone. The aim is for the parenteral nutrition to fit in with the family's lifestyle, rather than ending up with a “hospital at home.” The nutrition itself should be tailor made as a single bag. If at all possible, a portable pump should be available.
The key to success and keeping a child at home on parenteral nutrition is to have an effective multidisciplinary team who communicate well with each other and, most important, the parents. The practice at Great Ormond Street Hospital for Children has been to have a discharge-planning meeting at the local hospital and to set up a shared-care system of support with the community nurse and the local hospital, which is the first port of call in most situations. Once stable at home, the patient is reviewed at the specialist hospital only every 3 or 4 months. The patient will be readmitted or reviewed in more detail annually.
Parents were generally satisfied with the Great Ormond Street home parenteral nutrition service when anonymously surveyed. In general, they found the most difficult time was when the child was first discharged home. Some parents said that their relationship was strengthened and their self-esteem improved through managing intravenous feeding.
Children have been successfully discharged home on treatment with intravenous nutrition only in the past 20 years in the United Kingdom. The first child to go home from this hospital had hollow visceral myopathy. She is now in her early 20s and still dependent on intravenous feeding. She has grown and developed normally. Because she went home, 14 children with classical congenital intestinal neuromuscular pseudoobstruction have been discharged with intravenous feeding. It is only in the last 20 years since long-term intravenous feeding has been successfully used that the disease progress in this severely affected group of children could be ascertained.
Six of the 14 children presented with intestinal obstruction and required parenteral nutrition in the neonatal period. The other 8 first developed severe intestinal failure from 6 months to 14 years of age (mean, 4.5 years; median, 1.2 years). Twelve of the 14 children are still alive. Whilst all of the children have had prolonged episodes of severe intestinal failure, 2 have constantly been totally dependent on intravenous nutrition.
Two children died at the ages of 2 and 9 years, 1 from sepsis and the other from unknown causes. The remaining 12 are now 1 to 34 years old (mean, 15; median, 12 years). Liver disease has not developed in any child with pseudoobstruction.
The survival rate from date of starting parenteral nutrition was 100% (13 of 13 patients) 2-year survival and 92% (12 of 13) 5-year survival. The 10-year survival rate was 80% (8 of 10 children).
Over the longer term, intestinal transplantation may be an effective treatment to improve morbidity. However, the current mortality rate is so much higher than that of long-term intravenous feeding that it has not been feasible.
In summary, children with the most severe intestinal failure associated with congenital intestinal neuromuscular disease have a good life expectancy on treatment with intravenous nutrition.
1. Heneyke S, Smith VV, Spitz L, et al
. Chronic intestinal pseudo-obstruction: treatment and long term follow up of 44 patients. Arch Dis Child 1999; 81:21–27.
2. Smith VV, Milla PJ. Histological phenotypes of enteric smooth muscle disease causing functional intestinal obstruction in childhood. Histopathology 1997; 31:112–122.