Safety of N-acetylcysteine in treatment of meconium obstruction of the newborn

Abstract

I IX 1964 IMeeker and Kincannon reported on the liquifying effects of a mixture of N-acetylcysteine (N-AC) and hydrogen peroxide on inspissated meconium causing intestinal obstruction in 9 newborn infants.l This application of N-,4c was an outgrowth of experimental and clinical evidence demonstrating its effectiveness as a mucolytic agent, especially in the tracheobronchial tree.” Instilling a 1:l mixture of 20 per cent N-AC* and 1 per cent Hz02 into the bowel lumen for 30-50 minutes, Meeker and Kincannon found that the mixture caused considerable liquefaction of the meconium without adverse side effects. They noted, however, that in their cases of meconium ileus liquefaction was “slower and seemed less satisfactory” than in their cases of ruptured omphalocele and meconium peritonitis with obstruction. Since this report, N-AC has been widely used in the treatment of meconium obstructions in the newborn, such as meconium ileus and meconium plug. It has also been used in the relief of meconium ileus equivalent3 In 1967 and 1968 I used Mucomyst in varying strengths to evacuate “plugs” from six newborns. In 5 of these, after failure of saline enemas, Mucomyst was instilled into the rectum and subsequently a large meconium plug was evacuated. No adverse effects were noted. Because of the difficulty in accumulating enough clinical material on which to judge the efficacy of Mucomyst in meconium obstructions, the Surgical Section of the American Academy of Pediatrics was polled. A questionnaire was returned by 107 respondents, some of whom described the combined experience of several pediatric surgeons. Forty-five of the respondents had never used Mucomyst in meconium obstruction. Experience with 213 cases, including 38 meconium plugs and 175 cases of meconium ileus, was tabulated. The relative effectiveness of Mucomyst in the hands of the respondents is indicated in Tables 1 and 2. Ten respondents, or 15 per cent of those who had used Mucomyst, described adverse side effects which they felt may have been due to the Mucomyst instillation into infant rectum, small bowel, or peritoneal cavity. Several reported the appearance of shock following use of N-AC; others cited mucosal ulceration, fluid transudation, and other side effects. In some cases relief of obstruction was incomplete. Few respondents indicated whether the N-AC -_ __-__ From the Pediatric Surgical Diz;ision, Department of Surgery, St, Vincent’s Hospital a& hfedical Center, New York. AXTHONY SHAW, M.D.: Assistant Clinical Professor of Surgery, Columbia Linicersity College of Physicians and Surgeons. Supported in part hy a grant from the Mead-Johnson Research Laboratories, Eaansc;ille, Indiana. -____.__ “Mnrketed RS Mucomyst (Mead Johnson Co.)