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 (O2Hb), 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.