TY - JOUR
T1 - Near infrared spectroscopy evaluated cerebral oxygenation during anesthesia
AU - Sørensen, Henrik
PY - 2016/12/1
Y1 - 2016/12/1
N2 - Likely, maintained organ and notably cerebral perfusion, se-cures rapid recovery following anesthesia. To secure cerebral blood flow (CBF) at least mean arterial pressure (MAP) and the arterial carbon dioxide tension (PaCO2) need to be considered. CBF is “autoregulated”, i.e. stays more or less stable within a MAP of 50-150 mmHg, but the lower limit appears to depend on the central blood volume and/or cardiac output, illustrated by a decrease in CBF at a MAP of 80 mmHg with a compromised cen-tral blood volume, while CBF remains constant with a MAP <40 mmHg, if the central blood volume is maintained. During anes-thesia, MAP is often around 50 mmHg meaning that it remains unknown whether CBF is maintained, why an evaluation of CBF, e.g. by near-infrared spectroscopy (NIRS) seems desirable. NIRS is sensitive to changes in PaCO2, detects hypoxemia, identifies cerebral autoregulation as well as regional distribution of CBF. As summarized, especially elderly patients and patients undergoing complex surgery and notably heart and liver surgery, seem tobenefit from a strategy focusing on maintaining NIRS-determined cerebral oxygenation during anesthesia. Similarly, NIRS may be applied to guide the ventilatory strategy during anesthesia when there are large deviations in metabolism, seen when clamping ofthe aorta and with reperfusion of the lower body during open aortic surgery, as with hepatectomy and following reperfusion ofthe donated liver during liver transplantation surgery. Finally it is illustrated how NIRS can be applied to select sympathomimeticagents, used to correct anesthesia-induced hypotension in orderto preserve CBF and skin oxygenation.
AB - Likely, maintained organ and notably cerebral perfusion, se-cures rapid recovery following anesthesia. To secure cerebral blood flow (CBF) at least mean arterial pressure (MAP) and the arterial carbon dioxide tension (PaCO2) need to be considered. CBF is “autoregulated”, i.e. stays more or less stable within a MAP of 50-150 mmHg, but the lower limit appears to depend on the central blood volume and/or cardiac output, illustrated by a decrease in CBF at a MAP of 80 mmHg with a compromised cen-tral blood volume, while CBF remains constant with a MAP <40 mmHg, if the central blood volume is maintained. During anes-thesia, MAP is often around 50 mmHg meaning that it remains unknown whether CBF is maintained, why an evaluation of CBF, e.g. by near-infrared spectroscopy (NIRS) seems desirable. NIRS is sensitive to changes in PaCO2, detects hypoxemia, identifies cerebral autoregulation as well as regional distribution of CBF. As summarized, especially elderly patients and patients undergoing complex surgery and notably heart and liver surgery, seem tobenefit from a strategy focusing on maintaining NIRS-determined cerebral oxygenation during anesthesia. Similarly, NIRS may be applied to guide the ventilatory strategy during anesthesia when there are large deviations in metabolism, seen when clamping ofthe aorta and with reperfusion of the lower body during open aortic surgery, as with hepatectomy and following reperfusion ofthe donated liver during liver transplantation surgery. Finally it is illustrated how NIRS can be applied to select sympathomimeticagents, used to correct anesthesia-induced hypotension in orderto preserve CBF and skin oxygenation.
UR - http://www.scopus.com/inward/record.url?scp=85006333164&partnerID=8YFLogxK
M3 - Journal article
C2 - 27910802
AN - SCOPUS:85006333164
SN - 2245-1919
VL - 63
JO - Danish Medical Journal
JF - Danish Medical Journal
IS - 12
M1 - B318
ER -