Possible importance of increased intra-abdominal pressure for the development of necrotizing enterocolitis.

Background/Purpose: Despite extensive clinical and laboratory investigations, many aspects of the pathogenesis of necrotizing enterocolitis (NEC) remain unclear. In the present work we describe 5 neonates with NEC in whom intra-abdominal pressure (IAP) was measured to investigate the potential role of abdominal compartment syndrome (ACS) in the development of NEC and to correlate the severity of NEC with the value of IAP. Methods: IAP pressure was determined in two groups - Group A consisting of five patients without NEC (Control) and Group B consisting of five patients who developed NEC - by measuring the urinary bladder pressure (UBP). The correlation between increased IAP and severity of NEC, complications of NEC and indications for surgery was investigated. Results: In four patients from Group B, the general condition deteriorated despite aggressive supportive treatment, and a laparotomy was performed. These neonates demonstrated a significant increase (compared to Control patients) in UBP (9.0+/-2.5 vs. 4.8+/-1.4 mmHg, p=0.001), which increased progressively with exacerbation of NEC and reached a peak value of 13.3+/-2.4 mmHg before operation. The elevated IAP was accompanied by hemodynamic instability in all patients, respiratory instability in 3 patients and decreased urinary output in one patient. One patient remained unstable and died 6 h after operation. In the fifth patient from Group B, intestinal obstruction developed two weeks after NEC and did not result in increased IAP. Conclusions: Our results suggest that IAP is associated with an exacerbation of NEC. Thus, this study provides further information which may improve our understanding of the pathogenic process of NEC.