Near-infrared spectroscopy measure of limb peripheral perfusion in neonatal arterial thromboembolic disease.

Aim. In critically ill neonates, peripheral perfusion and oxygenation assessment may provide indirect information on circulatory failure in limb arterial thromboembolic emergencies. Aims of our study were: 1) to evaluate the changes on tissue oxygenation index, oxyhemoglobin, deoxyhemoglobin and blood volume obtained by near-infrared spectroscopy (NIRS) on the infants legs; 2) to compare them with ultrasonographic data. Methods. Tissue oxygenation index (TOI), oxyhemoglobin (O(2)Hb), deoxyhemoglobin (HHb) and blood volume (BV) differences were assessed by NIRS on the calf of 8 newborn infants (median weight 1995, range 585-3010 g; median gestational age 32.5, range 26-40 wks). An ultrasonographic scan of the arterial system was performed before the NIRS measurements, to validate the site of arterial occlusion. Results. A t-test for independent samples showed lower values in the affected limb for all NIRS measurements. TOI measurements displayed lower values in the thromboembolic limb (mean 44.79 +/- 12%) versus unaffected (mean 47.95 +/- 17.08%) (P=0.0001). Mean (SD) peak systolic velocity in the patent artery below the occlusion decreased from 108 +/- 25 cm/s in the normal limb to 25.6 +/- 28 cm/s in the thrombus site (P=0.02). Conclusion. In neonatal intensive care units, measurement of limb peripheral perfusion and oxygenation seems to be clinically useful in arterial thromboembolic emergencies.