Introduction
Although N-acetylcysteine (NAC) has been used to treat distal intestinal obstruction outside of the neonatal population, there have been limited studies regarding the guidelines to treat neonates. This case report focuses on the novel use of NAC postoperatively to treat distal intestinal blockage in a neonate with cystic fibrosis.
Case – History and Physical Exam Findings
A male neonate born at 39 weeks gestation via C-section in the setting of a failed induction was admitted to the neonatal intensive care unit with abdominal distension, non-bilious emesis, and failure to pass meconium. A gastrograffin enema showed a microcolon and total intestinal blockage with the obstruction either in the proximal colon or distal ileum. On day of life 3, the neonate underwent an exploratory laparotomy with ileostomy. Once the newborn screen reported positive for cystic fibrosis, the baby was started on pancreatic supplements.
At one month of age after adequate weight gain his pancreatic enzymes were held in preparation for closure of the stoma and bowel anastomosis. Immediately following surgery, the neonate had persistent abdominal distension. An X-ray demonstrated diffuse gaseous distension of bowel (Figure 1). A gastrografin enema showed a microcolon (Figure 2). The likely cause of intestinal obstruction was the necessary cessation of pancreatic enzymes prior to surgery. So, a novel approach to treating the obstruction was tried postoperatively. Oral 2% N-acetylcysteine (NAC) was given via a nasogastric tube. NAC was initially started at 5 ml every 4-6 hours. After 4 days of treatment, the neonate passed meconium and NAC was weaned to 2ml every 3 hours. By day 5 of treatment, the patient had complete resolution of intestinal obstruction and adequate stool production. NAC was discontinued after 9 days of treatment. A week later, he was discharged home with minimal adverse effects.
Diagnostic imaging
(Please see the attached images)
Final Diagnosis
A male neonate born at 39 weeks gestation with cystic fibrosis that presented with distal intestinal obstruction.
Discussion
The postoperative use of NAC is a novel approach for patients prone to develop distal intestinal obstruction. In our case pancreatic enzyme supplements were stopped preoperatively, possibly leading to blockage by formation of thick secretions in the distal small bowel. With that etiology in mind, NAC was used postoperatively so that an additional operation was mitigated. Additionally NAC has anti-inflammatory, anti-oxidant, and anti-bacterial properties which further aid in the healing process postoperatively. While the use of NAC has been reported to be associated with drug induced liver toxicity and hypernatremia, we found neither in our patient. Our case report demonstrates that low dose NAC could be administered postoperatively to obtain resolution of postoperative intestinal obstruction with minimal side effects.
