Initial Experience With Naloxone Hydrochloride for the Treatment of Acute Intestinal Pseudo-obstruction in Intensive Care Unit Patients

Abstract

BACKGROUND: In acute intestinal pseudo-obstruction there is dilation of the intestinal loops without mechanical obstruction; it may develop after surgery or severe illness. This condition is due to an acute imbalance of the normal extrinsic autonomic innervation of the bowel. Although it may resolve with conservative therapy, colonoscopic decompression is sometimes needed to prevent ischemia and perforation of the bowel. Studies suggest that neostigmine is an effective treatment. However there is no reported experience from India with Naloxone hydrochloride. Naloxone hydrochloride, an opiod antagonist, is a synthetic congener of oxymorphone. METHODS:We studied patients admitted in intensive care unit (ICU) fulfilling criteria of acute intestinal pseudoobstruction in the form of clinical abdominal distention and radiographic evidence of significant small bowel and colonic dilation. Reversible and mechanical causes of abdominal distenstion were ruled out. When there was no response to at least 24 hours of conservative treatment, we prospectively recruited patients to receive 3.0 mg of Naloxone (one ampule contains 0.4 mg, so seven and half ampule inj Naloxone) given through ryles tube, ryles tube clamped for one hour, medicine administered every 6 hours. A physician, who was unaware of the patients’ treatment assignments, recorded clinical responses defined as evacuation of flatus or stool and a reduction in abdominal distention, abdominal circumference, and measurements of the small bowel and colon on radiographs. Patients who had no response to the initial dose were eligible to receive open-label Naloxone 6 hours later and subsequent doses 6 hourly for 24 hours. RESULTS: Prospectively 19 patients were included in study since April 2014, 7 patients were having pneumonia, septicaemia, three patients with pylenephritis, septicaemia, one patient with cerebrovascular accident, intracranial bleed, one post complicated spinal surgery, 3 with polytrauma due to road traffic accident, one with CRF and septicaemia, one patient with subacute bacterial endocarditis, septicaemia, and 2 with cirhosis liver. Eleven patients who received Naloxone had early intestinal decompression in the form of passage of flatus, passage of motion, decrease in abdominal girth, significant decrease in bowel diameter on x-ray flat plate abdomen, improvement in clinical parameters especially respiratory rate, oxygen saturation. In one patient colonoscopic decompression and also an injection of Neostigmine 2 mg was required. The median time to response was 4 hours (range, 212). Side effects of Naloxone included tachycardia in two patients, rise in blood pressure, irritability in one patient each. CONCLUSION: This initial observation suggests that Ryles tube administration of Naloxone hydrochloride is beneficial and safe in the treatment of ICU-admitted patients with acute intestinal pseudoobstruction.