Impact of hypotension on cerebral perfusion during general anesthesia induction: A prospective observational study in adults

Introduction During anesthesia, decreases in mean arterial pressure (MAP) are common but the impact on possible cerebral hypoperfusion remains a matter of debate. We evaluated cerebral perfusion in patients with or without cardiovascular comorbidities (Hi‐risk vs Lo‐risk) during induction of general anesthesia and during hypotensive episodes. Methods Patients scheduled for neuroradiology procedure using standardized target‐controlled Propofol‐Remifentanil infusion were prospectively included. Monitoring included Transcranial Doppler (TCD) measuring mean blood velocity of the middle cerebral artery (Vm), Bispectral Index with burst suppression ratio (SR) and cerebral Near‐Infrared Spectroscopy (NIRS). Hypotensive episodes were treated with a 10 µg bolus of Norepinephrine. Results Eighty‐one patients were included, 37 Hi‐risk and 44 Lo‐risk. During induction of anesthesia, MAP and Vm decreased in all patients, with greater changes observed in Hi‐risk patients compared to Lo‐risk patients (−34 [38‐29]% vs −17 [25‐8]%, P