Comparison of regional transcranial oximetry with near infrared spectroscopy (NIRS) and jugular venous bulb oxygen saturation for the monitoring of cerebral oxygenation in infants and children

Using a dual channel near infrared (NIR) in vivo optical spectroscopy (INVOS(R)) system (INVOS 3100A(R), Somanetics Corp. Troy, MI, USA) we investigated the relationship between jugular venous oxygen saturation (SjvO(2)) and regional cerebral oxygen saturation (rSO(2)) in 30 infants and children (mean age 4.5 years) with congenital heart disease undergoing cardiac catheterisation. The NIRS-SomaSensor(R) (emitter and dual receiver probe) was applied at a standardised right fronto-temporal location lover the right frontal cortex) on the infant's head and covered with an adhesive flexible bandage Using NIR Light (730 and 810 nm) and two source-detector spacings (3 and 4 cm from the transmitter), percentage values of rSO(2) were calculated from detected haemoglobin saturations. Simultaneously, jugular venous oxygen saturation (SjvO(2)) monitoring was performed via a catheter placed in the right internal jugular vein with its tip positioned in the jugular bulb, as verified by fluoroscopy. To compare the reliability of NIRS measurement characteristics, jugular venous blood was analysed for SjvO(2) as a reference measure of global cerebral oxygenation, by co-oximetry (OSM3-Hemoximeter(R), Radiometer Copenhagen, Denmark). Other measured variables included pulse oximetry, arterial blood pressure, and venous and arterial oxygen saturations. Over a jugular venous oxygen saturation range of 31-83%, a significant positive linear correlation was found between rSO(2) (NIRS measurement) and SjvO(2) (jugular bulb oximetry) (r = 0.93, p < 0.001). No significant correlation was observed between rSO(2) values and arterial blood saturation or pulse oximetry. The quantitative correlation between rSO(2) (haemoglobin oxygenation in a small hemi-elliptical area of the brain) and reference SjvO(2) measurement (method for monitoring global cerebral oxygenation) suggests that NIRS measurement with subtraction algorithm should identify predominantly intracranial saturation in the pediatric age group, and will tend to reflect global oxygenation under physiological conditions. Transcranial oximetry using dual receiving channel NIRS offers a noninvasive, real-time, reliable and practicable means of monitoring cerebral haemoglobin oxygenation changes infants and children with cyanotic and noncyanotic congenital heart disease.