Impact of impaired cerebral blood flow autoregulation on electroencephalogram signals in adults undergoing propofol anaesthesia: a pilot study
Elsa Manquat,
Hugues Ravaux,
Manuel Kindermans,
Jona Joachim,
José Serrano,
Cyril Touchard,
Joaquim Mateo,
Alexandre Mebazaa,
Etienne Gayat,
Fabrice Vallée,
Jérôme Cartailler
Affiliations
Elsa Manquat
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France; AP-HP-Inria, Laboratoire Daniel Bernoulli, Paris, France; Corresponding author. Department of Anesthesiology and Intensive Care, Lariboisière – Saint Louis Hospitals, Paris, France.
Hugues Ravaux
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France
Manuel Kindermans
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France
Jona Joachim
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France
José Serrano
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France
Cyril Touchard
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France
Joaquim Mateo
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France
Alexandre Mebazaa
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France; INSERM, UMR-942, Paris, France
Etienne Gayat
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France; INSERM, UMR-942, Paris, France
Fabrice Vallée
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France; Laboratoire de Mécanique des Solides (LMS), Ecole Polytechnique/CNRS/Institut Polytechnique de Paris, France; INSERM, UMR-942, Paris, France
Jérôme Cartailler
Department of Anesthesiology, Burn and Critical Care, St-Louis-Lariboisiere University Hospital, Assistance Publique Hôpitaux de Paris, Paris, France; INSERM, UMR-942, Paris, France
Background: Cerebral autoregulation actively maintains cerebral blood flow over a range of MAPs. During general anaesthesia, this mechanism may not compensate for reductions in MAP leading to brain hypoperfusion. Cerebral autoregulation can be assessed using the mean flow index derived from Doppler measurements of average blood velocity in the middle cerebral artery, but this is impractical for routine monitoring within the operating room. Here, we investigate the possibility of using the EEG as a proxy measure for a loss of cerebral autoregulation, determined by the mean flow index. Methods: Thirty-six patients (57.5 [44.25; 66.5] yr; 38.9% women, non-emergency neuroradiology surgery) anaesthetised using propofol were prospectively studied. Continuous recordings of MAP, average blood velocity in the middle cerebral artery, EEG, and regional cerebral oxygen saturation were made. Poor cerebral autoregulation was defined as a mean flow index greater than 0.3. Results: Eighteen patients had preserved cerebral autoregulation, and 18 had altered cerebral autoregulation. The two groups had similar ages, MAPs, and average blood velocities in the middle cerebral artery. Patients with altered cerebral autoregulation exhibited a significantly slower alpha peak frequency (9.4 [9.0, 9.9] Hz vs 10.5 [10.1, 10.9] Hz, P<0.001), which persisted after adjusting for age, norepinephrine infusion rate, and ASA class (odds ratio=0.038 [confidence interval, 0.004, 0.409]; P=0.007). Conclusion: In this pilot study, we found that loss of cerebral autoregulation was associated with a slower alpha peak frequency, independent of age. This work suggests that impaired cerebral autoregulation could be monitored in the operating room using the existing EEG setup. Clinical trial registration: NCT03769142.
