Ileus

The usual presenting complain is pain and bloating. This pain is often mild and vague initially but is later described as cramps. They may also present with poor appetite, nausea and vomiting. Patients could also present with inability to pass faeces or flatus but this is not common in all patients. There is abdominal distension and the degree will depend in the level of the ileus. The abdomen will also be tympanic to percussion and there may be some degree of tenderness. A distinctive feature of ileus is the reduced or complete absence of bowel sounds on auscultation which is usually referred to as the silent abdomen [6].

• Plain abdominal X-ray is an important investigation in ileus. It is done with the patient in the supine and erect positions and it will show copious gaseous dilatation of the small intestine and colon. 
• Enteroclysis is an X-ray of the small intestine using liquid contrast and studying how it moves. It is expected that the contrast medium should reach the cecum within 4 hours if the patient has paralytic ileus. If it remains motionless for more than 4 hours, then mechanical obstruction is more likely.
• Ultrasound scans are also useful in the evaluation of this condition and can accurately exclude the condition in approximately 89% of patients.
• CT scan may be employed if a high index of suspicion remains despite normal X-ray findings.
• Laboratory investigations that could be done include complete blood count, erythrocyte sedimentation rate, and blood culture to evaluate for infections. Serum electrolytes, urea and creatinine as well as blood glucose studies should be done to check for metabolic imbalance [7]. 

• The management of this condition depends greatly on the surgical procedure performed and also on the nature of the disease. Management of this condition aims to resolve the underlying medical conditions, correct electrolyte imbalance and regulate acid base irregularities. 
• Most cases that occur postoperatively will resolve with supportive therapy and watchful waiting. Patients should be placed on intravenous infusion and a fluid chart kept to monitor intake and output. In patient who are vomiting and who have abdominal distension, a nasogastric tube may be passed to help relieve symptoms. Drugs that cause ileus like opiates should be discontinued. Non-steroidal anti-inflammatory drugs (NSAIDs) should be used instead for pain management and it also has the additional advantage of reducing local inflammation. The drugs of choice is Celobix (COX 2 selective agent) as it eliminates the unwanted effect of platelet dysfunction seen with non-selective NSAIDs [8].
• Oral feeding should be delayed until the ileus resolves clinically. It has been advocated that chewing gum helps to promote recovery from ileus postoperatively [9]. 
• Surgery may be required if the is a complication like perforation but this is rarely the case.

The prognosis is generally good as most cases of postoperative ileus resolve within 72 hours. Very rarely is there complication. The risk of a future occurrence is however increased in a patient who has had ileus [5].

The cause of ileus is still uncertain but there have been strongly linked associated risk factors. The main identified risk factor is major gastrointestinal surgery and the postoperative state is the most popular setting for development of ileus and it is an expected complication. Other contributing factors are electrolyte imbalance, hypothyrpidism, metabolic acidosis e.g. diabetic ketoacidosis, drugs like antimuscarinics and opiates, spinal cord injury above the fifth thoracic vertebrae, chest infections, cardiopulmonary failure like myocardial infarction, sepsis, intraabdominal inflammation and peritonitis, as well as biliary and renal colic [2].

Approximately 50% of people who undergo major abdominal surgery will develop ileus postoperatively. It is seen in all age groups although it is becoming more common in the elderly, probably due to increased surgical procedures now being performed in this age group. It has no sex preferences and affects individuals of all races [3].

The exact pathway by which ileus occurs is still unclear. It has been hypothesised that it might be mediated through activation of inhibitory spinal reflex arcs. 3 separate reflexes are involved, the long, short and ultrashort reflex. The long reflexes which involve the spinal cord is the most significant. Nerve cutting techniques have been seen to either diminish or prevent the development of ileus.
Usually, the response to surgical stress leads to systemic generation of endocrine and inflammatory mediators that then promote the development of ileus. Abdominal surgeries causes increased number of monocytes, macrophages, dendritic cells, natural killer cells, T cells and mast cells. Macrophages and mast cells are the key players in the inflammatory cascade. Other mediators are nitric oxide, calcitonin gene-related peptide, substance P and vasoactive inhibitory peptide and these serve as inhibitory neurotransmitters in the nervous system of the bowel [4].

Not much is available in terms of prevention of this condition. It occurs as a result of surgery, medical conditions and injuries which makes it difficult to control [10].

Ileus initially referred to any form of intestinal obstruction including mechanical obstruction. It is however now limited to intestinal obstruction resulting from failure of peristalsis. It is a very common post-operative complication in abdominal surgery [1].

• Definition: Ileus is a type of obstruction of the intestine that is not due to a mechanical cause i.e. blockage. Is arises when the normal movement of food and faecal matter in the intestines stop. It can be seen in any age group.
• Cause: More than half of the cases usually occur after surgery. Other causes may include, infections of the abdomen or chest, heart attack, certain types of drugs, injury to the intestine, imbalance of electrolytes like potassium and a previous history of ileus.
• Symptoms: The most common symptom is pain, this is initially vague but may become like cramps. There is also abdominal swelling, hiccups, nausea and vomiting and most patients will not be able to pass gas or stool.
• Diagnosis: Plain X-rays are usually enough to make a diagnosis of ileus. But ultrasound, CT scan and contrast X-rays also have their application. Blood tests will also be done to check for infections as well as underlying factors like electrolyte imbalance or diabetes.
• Treatment: The treatment is most often conservative as most postoperative cases resolve within 72 hours. Fluid is given intravenously, feeding is withheld and if necessary, stomach and small bowel is drained with a nasogastric tube. When drug treatment is instituted, it is to correct the underlying conditions.

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9. Asao T, Kuwano H, Nakamura J, et al. Gum chewing enhances early recovery from postoperative ileus after laparoscopic colectomy. J Am Coll Surg 2002; 195:30.
10. Yeh YC, Klinger EV, Reddy P. Pharmacologic options to prevent postoperative ileus. Ann Pharmacother. Sep 2009;43(9):1474-85