Carbon dioxide-related changes in cerebral blood volume and cerebral blood flow in mechanically ventilated preterm neonates: comparison of near infrared spectrophotometry and 133Xenon clearance. Export

@article{citeulike:3025227, abstract = {Carbon dioxide-induced changes in near infrared spectrophotometry recordings were compared with changes in cerebral blood flow estimated by 133Xenon clearance (global cerebral blood flow (infinity)) at serial measurements in 24 mechanically ventilated preterm infants (mean gestational age 30.2 wk). In all infants, three measurements were taken at different arterial carbon dioxide tension levels (mean 4.4 kPa, range 2.1-7.8) obtained by adjustment of the ventilator settings. Mean arterial blood pressure changed spontaneously, whereas arterial oxygen tension was kept within normal range. At all wavelengths (904, 845, 805, and 775 nm), the OD increased at higher arterial carbon dioxide tension levels, indicating cerebral vasodilation. This conclusion was supported by conversion of the data to changes in oxygenated and deoxygenated Hb concentration. A parallel increase in cerebral blood volume index and global cerebral blood flow (infinity) was found (p less than 0.0001). The oxygenation level of cytochrome aa3 increased with increases in oxygen delivery (p less than 0.0001). This observation, however, may have been artifactual due to cross-talk between the oxidized cytochrome aa3 and the oxygenated Hb signals, as these signals were closely interrelated in the present experimental design. We suggest that near infrared spectrophotometry may be used for estimation of the cerebral blood volume index/cerebral blood flow-CO2 reactivity within a wide range of arterial carbon dioxide tension. Knowledge of the light path length would put this estimation on a quantitative basis.}, address = {Department of Neonatology, State University Hospital (Rigshospitalet), Copenhagen, Denmark.}, author = {Pryds, O. and Greisen, G. and Skov, L. L. and Friis-Hansen, B.}, citeulike-article-id = {3025227}, citeulike-linkout-0 = {http://view.ncbi.nlm.nih.gov/pubmed/2161099}, citeulike-linkout-1 = {http://www.hubmed.org/display.cgi?uids=2161099}, issn = {0031-3998}, journal = {Pediatric research}, keywords = {adult, allages, chd, congenitalheartdefect, hypercapnia, neonatal, neonate, neonates}, month = {May}, number = {5}, pages = {445--449}, posted-at = {2008-07-21 19:59:46}, priority = {2}, title = {Carbon dioxide-related changes in cerebral blood volume and cerebral blood flow in mechanically ventilated preterm neonates: comparison of near infrared spectrophotometry and 133Xenon clearance.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/2161099}, volume = {27}, year = {1990} }

TY - JOUR ID - citeulike:3025227 L3 - citeulike-article-id:3025227 N2 - Carbon dioxide-induced changes in near infrared spectrophotometry recordings were compared with changes in cerebral blood flow estimated by 133Xenon clearance (global cerebral blood flow (infinity)) at serial measurements in 24 mechanically ventilated preterm infants (mean gestational age 30.2 wk). In all infants, three measurements were taken at different arterial carbon dioxide tension levels (mean 4.4 kPa, range 2.1-7.8) obtained by adjustment of the ventilator settings. Mean arterial blood pressure changed spontaneously, whereas arterial oxygen tension was kept within normal range. At all wavelengths (904, 845, 805, and 775 nm), the OD increased at higher arterial carbon dioxide tension levels, indicating cerebral vasodilation. This conclusion was supported by conversion of the data to changes in oxygenated and deoxygenated Hb concentration. A parallel increase in cerebral blood volume index and global cerebral blood flow (infinity) was found (p less than 0.0001). The oxygenation level of cytochrome aa3 increased with increases in oxygen delivery (p less than 0.0001). This observation, however, may have been artifactual due to cross-talk between the oxidized cytochrome aa3 and the oxygenated Hb signals, as these signals were closely interrelated in the present experimental design. We suggest that near infrared spectrophotometry may be used for estimation of the cerebral blood volume index/cerebral blood flow-CO2 reactivity within a wide range of arterial carbon dioxide tension. Knowledge of the light path length would put this estimation on a quantitative basis. IS - 5 JF - Pediatric research SN - 0031-3998 AD - Department of Neonatology, State University Hospital (Rigshospitalet), Copenhagen, Denmark. EP - 449 TI - Carbon dioxide-related changes in cerebral blood volume and cerebral blood flow in mechanically ventilated preterm neonates: comparison of near infrared spectrophotometry and 133Xenon clearance. VL - 27 SP - 445 KW - adult KW - allages KW - chd KW - congenitalheartdefect KW - hypercapnia KW - neonatal KW - neonate KW - neonates AU - Pryds, O AU - Greisen, G AU - Skov, LL AU - Friis-Hansen, B PY - 1990/05// UR - http://view.ncbi.nlm.nih.gov/pubmed/2161099 ER -