Utility of neuromonitoring in hypothermic circulatory arrest cases for early detection of stroke: Listening through the noise

• Published in: The Journal of thoracic and cardiovascular surgery Vol. 162; no. 4; pp. 1035 - 1045.e5
• Main Authors: Ghincea, Christian V., Anderson, Devon A., Ikeno, Yuki, Roda, Gavriel F., Eldeiry, Mohamed, Bronsert, Michael R., Aunkst, Kelly, Fullerton, David A., Reece, T. Brett, Aftab, Muhammad
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2021
• Subjects: aortic arch; hypothermic circulatory arrest; neuromonitoring; neuroprotection; stroke; MRI; EEG; HCA; stroke; SSEP; neuromonitoring; CT; NPV; neuroprotection; PPV; NIRS; MEP; hypothermic circulatory arrest; aortic arch; NIOM
• ISSN: 0022-5223; 1097-685X
• DOI: 10.1016/j.jtcvs.2020.01.090

Stroke remains a potentially devastating complication of aortic arch intervention. The value of neurophysiologic intraoperative monitoring (NIOM) in the early identification of stroke is unclear. We evaluated the utility of NIOM for early stroke detection in aortic arch surgery. Across 8 years at our institution, 365 patients underwent aortic arch surgery with hypothermic circulatory arrest, and 224 cases utilized NIOM. One patient was excluded for intraoperative death. In the remaining cohort, we reviewed the incidence, timing, and location of strokes, and the incidence and nature of NIOM alerts. Hemiarch was performed in 154 patients and total arch replacement in 69 patients. Stroke occurred in 6.3% of all cases (14 out of 223), 15.9% of total arches (11 out of 69), and 2.0% of hemiarches (3 out of 154). There were 33 NIOM alerts (14.8%), and 9 patients had both alerts and stroke. Of these, NIOM deficits plausibly correlated with imaging findings in 7 cases (78%). Of the 5 stroke patients without NIOM alerts, 2 developed neurologic symptoms 3 days or more postoperatively, and infarcts in 3 patients did not result in sensory or motor deficits. Excluding 2 patients with late stroke, the sensitivity of NIOM for stroke detection was 75%, specificity was 88.5%, positive predictive value was 27.3%, and negative predictive value was 97.4%. Despite a low positive predictive value requiring a high level of discrimination when interpreting abnormal findings, NIOM has high sensitivity and specificity for the early stroke detection. Furthermore, its high negative predictive valve is reassuring for low risk of stroke in the absence of alerts. Neuromonitoring during aortic arch surgery has high sensitivity and specificity for early detection of stroke, despite a low positive predictive value for permanent neurologic deficits, alerts can correspond to correctable intraoperative abnormalities as well as stroke. Intraoperative identification of neurologic deficits can lead to intraoperative interventions to reverse deficits, and earlier postprocedural neurologic imaging and catheter-based interventions if indicated. Furthermore, the high negative predictive value of neuromonitoring means that patients without neuromonitoring alerts are very unlikely to have a postoperative stroke. [Display omitted]