Validation of Cerebral Venous Oxygenation Measured Using Near-Infrared Spectroscopy and Partial Jugular Venous Occlusion in the Newborn Lamb

Abstract

Near-infrared spectroscopy combined with partial jugular venous occlusion (JVO) offers promise for determining cerebral venous saturation (CSvO 2 ) in sick preterm infants, but has not been validated in the newborn brain or under conditions of hypoxaemia. We assessed the accuracy of the CSvO 2 estimate using cerebral venous oxygen saturation in superior sagittal sinus blood (SSSO 2 ) as the 'gold standard'. Comparisons were made in seven newborn lambs over a wide range of arterial oxygen saturations (SaO 2 ) of 20% to 100%. Overall, median (range) CSvO 2 was 49.8% (10.6% to 88.5%), whereas SSSO 2 was 45.5% (4.3% to 76.6%); Bland-Altman analysis revealed a mean difference (CSvO 2 ÀSSSO 2 ) of 5.1% and limits of agreement of 627.4%. The change in cerebral blood volume (DCBV) induced by JVO increased with SaO 2 (P < 0.05). In addition, the strength of the correlation of CSvO 2 with SSSO 2 progressively improved with increasing change in total haemoglobin concentration (DHbT) induced by JVO. With Bland-Altman analysis repeated for data with DHbT > 30 lmol cm, the mean difference (CSvO 2 ÀSSSO 2 ) decreased to 2.4% with limits of agreement of 618.8%. We conclude that the accuracy of estimating CSvO 2 varies with the DCBV induced by JVO. Potential differences of optical properties between the head of the lamb and the human infant suggest that caution be exercised in directly applying these data to the human newborn. Nevertheless, this critical aspect of the JVO technique needs to be taken into consideration in developing an accurate measurement for sick preterm human infants.

Using near-infrared spectroscopy to measure cerebral metabolic rate of oxygen under multiple levels of arterial oxygenation in piglets

“…The noise-related error source can be partially addressed by only accepting data for which a minimum change in total hemoglobin concentration (⌬HbT ϭ ⌬HbO 2 ϩ ⌬HHb) was witnessed. Wong et al (35) observed that the coefficient of correlation between PVO-CSv O 2 and SS-Sv O 2 improved with increasing ⌬HbT in newborn lambs. For consistency, we applied a similar threshold (⌬HbT Ͼ 4 M) to the data in the present study, which improved the coefficients of correlation for the HT and PVO techniques from 0.73 and 0.81 to 0.81 and 0.84, respectively.…”

“…Manipulations were maintained for ϳ20 s and repeated three times for each technique. The parameters of interest, ⌬HbO 2 and ⌬HHb, were calculated by subtracting baseline relative HbO2 and HHb values-averaged over 10 s immediately before CBV manipulation-from relative values of HbO2 and HHb averaged over the first 5 s of manipulation (35). Measurements of CMR O 2 were calculated from the Fick principle with CSvO 2 measurements from each NIRS technique and from the sagittal sinus blood samples (SS-SvO 2 ) (28):…”

Cerebral Near-Infrared Spectroscopy during Transition of Healthy Term Newborns

“…This could be due to a lower oxygen extraction and therefore higher venous saturations in preterm infants. Differences between the ratio of the arterial and venous compartment could exist between term and preterm infants [23]. Another explanation would be that, due to the smaller head diameter in VLBW infants, more central parts of the brain will be measured, or that the thinner bone and skin of the preterm infant causes different scattering of light.…”

Monitoring Cerebral Oxygenation in Neonates: An Update

“…However, the difference between jugular venous oxygen saturation and regional cerebral oxygenation may increase during hypoxia. This is presumably caused by an increased arterial contribution to the NIRS signal due to cerebral arterial vasodilatation as a response to hypoxia (35). Cerebral fractional tissue oxygen extraction (cFTOE) has been validated against central cerebral venous saturation in newborn piglets (36).…”