Intraoperative-evoked Potential Monitoring: From Homemade to Automated Systems No abstract available

Cortical Oscillations and Connectivity During Postoperative Recovery Background: The objective of this study was to test whether postoperative electroencephalographic (EEG) biomarkers, parietal alpha power and frontal-parietal connectivity, were associated with measures of clinical recovery in adult surgical patients. Methods: This is a secondary analysis of a prospective cohort study that analyzed intraoperative connectivity patterns in adult surgical patients (N=53). Wireless, whole-scalp EEG data were collected in the postanesthesia care unit and assessed for relevance to clinical and neurocognitive recovery. Parietal alpha power and frontal-parietal connectivity (estimated by weighted phase lag index) were tested for associations with postanesthesia care unit discharge readiness and University of Michigan Sedation Scale scores upon postoperative admission. Bivariable correlation and regression models were constructed to test for unadjusted associations, then multivariable regression models were constructed to adjust for confounding. Results: Postoperative EEG patterns were characterized by a predominance of alpha parietal power and frontal-parietal connectivity. Neither relative parietal alpha power (% alpha, −0.25; 95% confidence interval [CI], −1.41 to 0.90; P=0.657) nor alpha frontal-parietal connectivity (weighted phase lag index, −82; 95% CI, −237 to 73; P=0.287) were associated with time until postanesthesia discharge criteria were met. Furthermore, neither alpha power (−0.03; 95% CI, −0.07 to 0.01; P=0.206) nor alpha frontal-parietal connectivity (−4.2; 95% CI, −11 to 2.6; P=0.226) were associated with sedation scores upon initial assessment. Conclusions: In a pragmatic study investigating clinically relevant endpoints of postoperative recovery, we found no correlation with surrogate measures of brain neurodynamics. These data contribute to the overall impetus of developing anesthetic-invariant and generalizable markers of brain recovery. Supported by the National Institutes of Health, Bethesda, MD, Grants R01GM098578 and K23GM126317 (P.E.V.). Previous presentations of the work: the authors previously published a separate, distinct line of analysis from these participants that focused on dynamic cortical connectivity patterns intraoperatively (Vlisides et al. Anesthesiology 2019;130(6):885–897). In addition, data from this investigation were presented in poster format at the 2019 University of Michigan School of Nursing Honors Symposium (September 4, 2019, Ann Arbor, MI). The authors have no conflicts of interest to disclose. Address correspondence to: Phillip E. Vlisides, MD. E-mail: pvliside@med.umich.edu. Received April 24, 2019 Accepted July 19, 2019 Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Impact of a Perioperative Protocol on Length of ICU and Hospital Stay in Complex Spine Surgery Background: In an attempt to improve patient care, a perioperative complex spine surgery management protocol was developed through collaboration between spine surgeons and neuroanesthesiologists. The aim of this study was to investigate whether implementation of the protocol in 2015 decreased total hospital and intensive care unit (ICU) length of stay (LOS) and complication rates after elective complex spine surgery. Materials and Methods: A retrospective cohort study was conducted by review of the medical charts of patients who underwent elective complex spine surgery at an academic medical center between 2012 and 2017. Patients were divided into 2 groups based on the date of their spine surgery in relation to implementation of the spine surgery protocol; before-protocol (January 2012 to March 2015) and protocol (April 2015 to March 2017) groups. Outcomes in the 2 groups were compared, focusing on hospital and ICU LOS, and complication rates. Results: A total of 201 patients were included in the study; 107 and 94 in the before-protocol and protocol groups, respectively. Mean (SD) hospital LOS was 14.8±10.8 days in the before-protocol group compared with 10±10.7 days in the protocol group (P<0.001). The spine surgery protocol was the primary factor decreasing hospital LOS; incidence rate ratio 0.78 (P<0.001). Similarly, mean ICU LOS was lower in the protocol compared with before-protocol group (4.2±6.3 vs. 6.3±7.3 d, respectively; P=0.011). There were no significant differences in the rate of postoperative complications between the 2 groups (P=0.231). Conclusion: Implementation of a spine protocol reduced ICU and total hospital LOS stay in high-risk spine surgery patients. Study was presented under the name: “Protocolized Perioperative Care for Complex Spine Surgeries and the Resulting Reduction in ICU/Hospital Length of Stay” at: (1) American Society of Anesthesiologists (ASA) Annual Meeting in San Francisco, October 13, 2018 (Session EA-19-1). (2) SNACC Annual Meeting in San Francisco on October 12, 2018. The authors have no funding or conflicts of interest to disclose. Address correspondence to: Eugenia Ayrian, MD. E-mails: eayrian@med.usc.edu; eugenia.ayrian@gmail.com. Received August 28, 2018 Accepted July 11, 2019 Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

Put the Kibosh On Bias No abstract available

Erector Spinae Plane Block For Postoperative Analgesia in Lumbar Spine Surgery: Is There a Better Option? No abstract available

General Anesthetic Agents Are Not Neuroprotective and May be Neurotoxic No abstract available

In Remembrance of Hiroshi Takeshita, MD, Pioneering Neuroanesthesiologist No abstract available

Correlation Between Electroencephalography and Automated Pupillometry in Critically Ill Patients: A Pilot Study Background: Electroencephalography (EEG) is widely used in the monitoring of critically ill comatose patients, but its interpretation is not straightforward. The aim of this study was to evaluate whether there is a correlation between EEG background pattern/reactivity to stimuli and automated pupillometry in critically ill patients. Methods: Prospective assessment of pupillary changes to light stimulation was obtained using an automated pupillometry (NeuroLight Algiscan, ID-MED, Marseille, France) in 60 adult patients monitored with continuous EEG. The degree of encephalopathy and EEG reactivity were scored by 3 independent neurophysiologists blinded to the patient’s history. The median values of baseline pupil size, pupillary constriction, constriction velocity, and latency were collected for both eyes. To assess sensitivity and specificity, we calculated areas under the receiver-operating characteristic curve. Results: The degree of encephalopathy assessed by EEG was categorized as mild (42%), moderate (37%), severe (10%) or suppression-burst/suppression (12%); a total of 47/60 EEG recordings were classified as “reactive.” There was a significant difference in pupillary size, constriction rate, and constriction velocity, but not latency, among the different EEG categories of encephalopathy. Similarly, reactive EEG tracings were associated with greater pupil size, pupillary constriction rate, and constriction velocity compared with nonreactive recordings; there were no significant differences in latency. Pupillary constriction rate values had an area under the curve of 0.83 to predict the presence of severe encephalopathy or suppression-burst/suppression, with a pupillary constriction rate of < 20% having a sensitivity of 85% and a specificity of 79%. Conclusions: Automated pupillometry can contribute to the assessment of cerebral dysfunction in critically ill patients. S.H., L.P., L.C., J.-L.V., and F.S.T.: conceived and designed the study. F.S.T., S.H., L.P., N.G., and L.C.: selected the population. S.H., L.P., L.C., and L.F.: screened and collected data from the population. L.F., B.L., and N.G.: analyzed the EEG recordings. F.S.T., J.C., and N.G.: conduced the statistical analysis. F.S.T., M.O., S.H., and L.P.: wrote the first draft of the manuscript. J.C., N.G., B.L., L.F. and J.-L.V.: revised the text for intellectual content. All the co-authors read and approved the final text. M.O. received lecture fees from Neuroptics. The remaining authors have no conflicts of interest to disclose. Address correspondence to: Fabio S. Taccone, MD, PhD. E-mail: ftaccone@ulb.ac.be. Received January 9, 2019 Accepted June 13, 2019 Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved

General Anesthetics Are Neuroprotective No abstract available

Perioperative Management of Direct Oral Anticoagulants in Intracranial Surgery The use of direct oral anticoagulants is increasing rapidly, because of perceived benefits over older agents, such as predictable pharmacokinetics and a reduced risk of bleeding. Elderly patients, who are more likely to be prescribed these drugs, are also presenting for neurosurgical procedures more often. The combination of these factors will result in neurosurgeons and neuroanesthesiologists encountering patients prescribed direct oral anticoagulants on an increasingly frequent basis. This review provides a summary of the current evidence pertaining to the perioperative management of these drugs, in the context of elective and emergency intracranial surgery. It highlights emerging therapies, including specific antidotes, as well as areas where the evidence base is likely to improve in the future. The authors have no funding or conflicts of interest to disclose. Address correspondence to: John Porter, MD, FRCA, FFICM, E-mail: johnporter@nhs.net. Received March 30, 2019 Accepted June 12, 2019 Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved