Neonatal pneumoperitoneum: a critical appraisal of its causes and subsequent management from a developing country.

Background: The diagnosis and management of neonatal pneumoperitoneum revolves around necrotizing enterocolitis (NEC) in most of the published literature. Although NEC remains the major cause of pneumoperitoneum in a neonate, there are several other causes leading to free air in the peritoneal cavity. A number of case reports have appeared describing pneumoperitoneum in a newborn due to rupture of one particular organ, but there have been only few collective reviews on the subject. The present study shares the experience with neonates admitted with a diagnosis of pneumoperitoneum in a pediatric surgical center of a developing country. The various causes of pneumoperitoneum in a newborn, their management and subsequent outcome are described.

Materials And Methods: The study was conducted in the Department of Pediatric Surgery, CSMMU (upgraded King Georges Medical College), Lucknow, India. All the neonates admitted with a diagnosis of pneumoperitoneum during the period of last 3 years (2005-2008) were retrospectively analyzed. Other neonatal admissions were also retrieved for the same period. Free air was confirmed by erect abdominal X-ray or lateral decubitus films in certain cases. The data sheets were analyzed regarding age of presentation, cause of bowel perforation, management offered and subsequent outcome achieved. All patients of NEC without evidence of perforation were not included in the study (n = 21).

Results: Out of total 537 neonatal admissions, 89 (16.5%) neonates were admitted with a diagnosis of pneumoperitoneum. There were 79 (88.7%) males and only 10 (11.6%) female neonates admitted during the study period. All of them had evidence of pneumoperitoneum at the time of admission. The age at presentation ranged from 4 to 32 days. NEC remained the single major cause of pneumoperitoneum in the newborn; however, in 44 (49.4%) patients the cause was not related to NEC. Perforated pouch colon, isolated colonic perforations, caecal perforations, gastric and duodenal perforations were the main causes of pneumoperitoneum not related to NEC. There were seven patients in whom no cause of pneumoperitoneum could be ascertained. The treatment was individualized according to the presentation. Most of the NEC-related perforations were managed by peritoneal drains. Laparotomy was done in rest of the patients. Three patients were managed conservatively. Overall, 19 (21.6%) patients expired. Most of those expired were of low birth weight with NEC and congenital pouch colon with perforation.

Conclusion: Neonatal pneumoperitoneum remains a surgical emergency and outcome can be lethal if the problem is not addressed early. NEC remains the major cause; however, there are several other important causes of isolated gastrointestinal perforations leading to neonatal pneumoperitoneum. The management should be individualized in these patients and the outcome largely depends on the early recognition of the condition.