Regional Haemoglobin Oxygen Saturation in the Splanchnic Circulation in Neonates With Gastroschisis; Quantifying and Qualifying the Role for Routine Monitoring

Gastroschisis is one of the most common neonatal surgical conditions, and is increasing in incidence. Postnatal bowel ischemia leading to necrosis, bowel loss and short-bowel syndrome, occurs in a few instances, with significant impact. Intestinal gangrene occurs in up to 37%. The cause of the gangrene can be multifactorial. Contributing factors can be volvulus; venous engorgement with ensuing arterial compromise; constriction of the gut mesentery at the defect; and contribution of the hydrostatic effect of the column of bowel within a silo.

Theoretically, the increased hydrostatic pressure incurred by the bowel in a preformed silo, may decrease blood flow to the apex of the bowel and contribute to ischemia. However, this does not seem to be the norm, as most cases do well in the silo. Cases of intestinal ischaemia within the silo have been described in patients. Any objective measure of bowel perfusion and therefore viability which can aid clinical assessment and management may benefit patient outcome.

Near-infrared spectroscopy (NIRS) is used to noninvasively measure and monitor changes in the approximate regional haemoglobin oxygen saturation (SO2) in the blood. Measurement of oxygen saturation using NIRS is already in clinical application in other neonatal and paediatric medical and surgical diseases. NIRS has been recommended as a good trend indicator of changes in neonatal tissues oxygenation. NIRS-measured duration of cerebral oxygen desaturation is an accurate predictor of postoperative neurological injury in children undergoing cardiac surgery.

The investigators propose to use NIRS to measure SO2 in the intestinal bed in patients with gastroschisis and to ascertain if there is any clinical advantage to routine monitoring in these patients.

The aim of the study will be to:

1. Measure Gastrointestinal SO2 (GSO2) of the bowel within the silo of gastroschisis patients
2. Identify the clinical progress of patients with gastroschisis in the postnatal period
3. Identify any association of the measured GSO2 with the clinical outcome and any gastrointestinal complications