The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts


Tala Nasr1Susan A. Roark1, Esther Taylor1, James E. Moore1

Introduction: Necrotizing Entercolitis (NEC)is a significant cause of morbidity and mortality in the neonatal intensive care unit. Decreased perfusion to the intestines may contribute to its pathophysiology. Current methods used to evaluate perfusion offer more systemic rather than regional information. Near Infrared Spectroscopy(NIRS)is a noninvasive technology that can measure regional oxygenation by measuring and continuously recording the weighted average of arterial and venous tissue saturations. This indirectly measures regional perfusion. Previous studies have shown NIRS probes placed on the abdomen can accurately measure the level of intestinal oxygenation.

Case Summary:
A 5wk old, ex-27 week infant was transfered to our facility for evaluation and management of NEC. On admission she was lethargic and pale with delayed capillary refill. Her abdomen was markedly distended with erythematos discoloration throughout. Radiographs demonstrated portal venous gas and pneumatosis intestinalis in the right and mid-abdomen. Approximately 24hrs after the diagnosis of NEC was made, a NIRS probe was placed on the infants abdomen midway between her umbilicus and pubis symphysis. Another was placed on her forehead to measure cerebral saturations. Initial readings were 60%+/- regional oxygen saturation(rS02)for the mesenteric bed,and 70%+/- for the cerebral saturation(cS02). The readings stayed within this range over the next 6hrs despite continued deteriation of the infant. Exploratory laporotomy demonstrated all bowel to be viable with no frank perforations. There were a few patchy small areas of gangrene noted but nothing extensive enough to excise.

Near-infrared spectroscopy of the cerebral vascular bed is being used increasingly in the management of infants during cardiac surgery and extracoporeal membrane oxygenation(ECMO). Studies demonstrate a high correlation between cS02 and ischemic events. Less information is available reguarding the use of NIRS monitoring for other vascular beds such as splanchnic circulation. Despite our patients poor clinical presentation and deteriation the NIRS readings supported the surgical findings. Studies have shown that NIRS monitoring may be helpful in predicting NEC when the values are very low. Here we demonstrate that these values may also be useful in predicting the presence of healthy tissue.