Quantitation of the concordance between cerebral intravascular oxygenation and mean arterial blood pressure for the detection of impaired autoregulation.
Since some important forms of brain injury in premature infants are caused in considerable part by disturbances in cerebral blood flow (CBF), it is important to be able to detect whether the cerebrovascular autoregulation, the mechanism by which CBF is maintained constant despite alterations in mean arterial blood pressure (MAP), is working properly. A recent study suggested that concordant changes in MAP and cerebral intravascular oxygenation (HbD), measured non-invasively by near-infrared spectroscopy (NIRS) as the difference between the concentration changes of oxygenated hemoglobin (HbO2) and deoxygenated hemoglobin (Hb), reflect impaired cerebrovascular autoregulation. Consequently, premature infants with impaired cerebrovascular autoregulation could be identified by simultaneous, continuous measurements of HbD and MAP. From several premature babies, MAP, HbD and arterial oxygen saturation (SaO2) were measured simultaneously at the University Hospital Leuven, Belgium. The concordance between MAP and HbD was quantitated using three different measures, among which a newly developed measure that looks for similarity of the dynamics between signals. Some preliminary results obtained from the measured data are given.
Morren
Geert
G
SCD/SISTA Division, Dept. of Electrical Engineering (ESAT), K.U.Leuven, Kasteelpark Arenberg 10, 3001 Leuven, Belgium.
Naulaers
Gunnar
G
Lemmerling
Philippe
P
Van Huffel
Sabine
S
Casaer
Paul
P
Devlieger
Hugo
H
D001794:Blood Pressure / Q000502:physiology*; D001812:Blood-Brain Barrier; D001930:Brain Injuries / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D006454:Hemoglobins / Q000378:metabolism; D006706:Homeostasis; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption / Q000502:physiology; D010108:Oxyhemoglobins / Q000378:metabolism
D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin; D010100:Oxygen