Every year, 300,000 patients head to the operating room for the repair of an acute intestinal obstruction, a potentially life- threatening condition in which the products of digestion are trapped in the bowel. This can occur as a result of a physical blockage (e.g. presence of a mass) or because there is aberrancy in the normal bowel physiology. Although there are numerous causes for this condition, the most commonly recognized one is the presence of adhesions, which are scar tissue formations that occur after any surgical intervention. Unfortunately, an intestinal obstruction may cause a number of non-specific symptoms that can mimic a great variety of bowel disorders, leading some patients to stay at home as they incorrectly attribute their symptoms to a benign illness rather than a bowel obstruction. Because the mortality risk of this disorder is directly proportional to the duration of illness, it is critical that patients undergo a prompt evaluation and diagnosis. If recognized early, conservative treatment might suffice, but if the intestinal obstruction has been present for a prolonged period of time, emergency surgery will surely be warranted.
In order to understand why an obstruction occurs, one must first review the normal intestinal physiology. When food enters the small intestine, the nervous system signals the initiation of a process known as peristalsis, a muscular contraction that pushes the food through the rest of the bowel. Any anomaly within this operation will impede the flow of intestinal contents. During an obstruction, the bowel wall above the blocked site stretches and this thinning leads to a decrease in blood flow resulting in death of the intestinal tissue. Other common causes of a passageway obstruction include hernias, tumors, volvulus (twisting of bowel), and foreign bodies. Yet, when it comes to the functional causes of an obstruction (a.k.a. pseudo-obstruction), diseases affecting the intestinal musculature or the nervous system are the typical culprits (e.g. diabetes, Parkinson’s). The typical symptoms of an intestinal obstruction include abdominal pain and distension, nausea, vomiting, and the inability to pass stool. The diagnosis can be made with a combination of the patient’s physical examination and a radiographic study such as a CT scan. The initial treatment involves the insertion of a nasogastric tube, which is used to disrupt the blockage, but if this therapy fails, the patient will have to undergo surgery.
The rate of complication with an intestinal obstruction is 42%; those who have a hernia as the primary cause are at the highest risk for this. As stated above, patients who undergo abdominal surgery [irrespective of the type of surgery or the time of onset of the procedure] are likely to develop adhesions and this can put them at risk for a bowel obstruction. Given that this is not a preventable disease, the most critical step is for people to be aware of how it presents itself, especially if they have any of the aforementioned risks. There is a phrase frequently cited by surgeons which states, “the sun should never rise or set on a small bowel obstruction,” which means that urgent medical attention should be given to all patients with an intestinal obstruction, as any delay in treatment may result in an internal infection or even death.