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Extracorporeal membrane oxygenation (ECMO) is used in critically ill patients with coronavirus disease 2019 (COVID-19) with acute respiratory distress syndrome unresponsive to other interventions. However, a COVID-19 infection may result in a differential tolerance to both medical treatment and ECMO management. The aim of this study was to compare outcomes (mortality, organ failure, circuit complications) in patients on ECMO with and without COVID-19 infection, either by venovenous (VV) or venoarterial (VA) cannulation. This is a multicenter, retrospective analysis of a national database of patients placed on ECMO between May 2020 and January 2022 within the United States. Nine-hundred thirty patients were classified as either Pulmonary (PULM, n = 206), Cardiac (CARD, n = 279) or COVID-19 (COVID, n = 445). Patients were younger in COVID groups: PULM = 48.4 ± 15.8 years versus COVID = 44.9 ± 12.3 years, p = 0.006, and CARD = 57.9 ± 15.4 versus COVID = 46.5 ± 11.8 years, p < 0.001. Total hours on ECMO were greatest for COVID patients with a median support time two-times higher for VV support (365 [101, 657] hours vs 183 [63, 361], p < 0.001), and three times longer for VA support (212 [99, 566] hours vs 70 [17, 159], p < 0.001). Mortality was highest for COVID patients for both cannulation types (VA-70% vs 51% in CARD, p = 0.041, and VV-59% vs PULM-42%, p < 0.001). For VA supported patients hepatic failure was more often seen with COVID patients, while for VV support renal failure was higher. Circuit complications were more frequent in the COVID group as compared to both CARD and PULM with significantly higher circuit change-outs, circuit thromboses and oxygenator failures. Anticoagulation with direct thrombin inhibitors was used more often in COVID compared to both CARD (31% vs 10%, p = 0.002) and PULM (43% vs 15%, p < 0.001) groups. This multicenter observational study has shown that COVID patients on ECMO had higher support times, greater hospital mortality and higher circuit complications, when compared to patients managed for either cardiac or pulmonary lesions. [ABSTRACT FROM AUTHOR]

Background Intraoperative neuromonitoring (IONM) is often used during cerebral endovascular procedures. Objective To investigate the relationship between intraoperative vascular complications and IONM signal changes, and the impact of interventions on signal resolution and postoperative outcomes. Methods A series of 2278 cerebral endovascular procedures conducted under general anesthesia and using electroencephalography and somatosensory evoked potential monitoring were retrospectively reviewed. A subset of 763 procedures also included motor evoked potentials (MEPs). IONM alerts were categorized as either a partial attenuation or complete loss of signal. Vascular complications were subcategorized as due to rupture, emboli, instrumentation, or vasospasm. Odds ratios (ORs) for new postoperative motor deficits were calculated and diagnostic accuracy was measured using sensitivity, specificity, and likelihood ratios. Results The overall incidence of new postoperative motor deficit was 1.2%; 20.4% in cases with an IONM alert and 0.09% in cases without an alert. Relative to procedures with no alerts, odds of a new deficit increased if there was partial signal attenuation (OR=210.9, 95% CI 44.3 to 1003.5, p<0.0001) and increased further with complete loss of signal (OR=1437.3, 95% CI 297.3 to 6948.2, p<0.0001). Relative to procedures with unresolved alerts, odds of a new deficit decreased if the alert was fully resolved (OR=0.039, 95% CI 0.005 to 0.306, p<0.002). Procedures using MEPs had slightly higher sensitivity (92.3% vs 85.7%) but slightly lower specificity (96.7% vs 98.2%). Conclusions An IONM alert associated with an arterial complication is associated with a dramatic increase in odds of a new postoperative deficit; however, if there is resolution of the alert prior to closure, odds of a new deficit decrease significantly. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: Continuous intraoperative neuromonitoring (IONM) of transcranial electric motor evoked potentials (tceMEPs) and somatosensory evoked potentials (SSEPs) has gained universal acceptance as an efficacious method for detecting emerging positional brachial plexopathy or peripheral nerve compression during spinal and shoulder surgery. This has implications for transaxillary thyroid surgery. Study Design: Case report with literature review. Methods: The patient underwent robotic transaxillary thyroid surgery with continuous tceMEP and SSEP monitoring of brachial plexus function. We present detailed IONM data depicting the emergence of positional brachial plexopathy. Results: Significant amplitude loss of both IONM modalities were identified during an evolving positional plexopathy, which resolved upon upper extremity repositioning and conversion to an open procedure. No permanent nerve injury or deficit was noted following surgery. Conclusions: Given the potential for brachial plexus injury during robotic transaxillary thyroid surgery secondary to arm positioning, we recommend that continuous tceMEP and SSEP monitoring be considered during such procedures. [ABSTRACT FROM AUTHOR]

The peroneal nerve is susceptible to injury due to compression at the fibular head for patients placed in the lithotomy, hemilithotomy or lateral decubitus positions during surgery. Upper extremity somatosensory and transcranial electric motor evoked potential monitoring has proven efficacious for identifying impending positional brachial plexopathy or upper extremity peripheral neuropathy in adult and pediatric patients undergoing spine surgery. We report on two cases to illustrate the usefulness of monitoring transcranial electric motor evoked potentials recorded from tibialis anterior muscle to identify emerging peroneal nerve compression secondary to lateral decubitus positioning. [ABSTRACT FROM AUTHOR]

This study was a retrospective review of 3,806 patients who underwent anterior cervical spine surgery with multi-modality neurophysiological monitoring consisting of transcranial electric motor evoked potentials, somatosensory evoked potentials and spontaneous electromyography between 1999-2003. The objectives of this study were twofold: (1) to evaluate the role of transcranial electric motor evoked potential tceMEP and ulnar nerve somatosensory evoked potential (SSEP) monitoring for identifying impending position-related stretch brachial plexopathy, peripheral nerve entrapment/compression or spinal cord compression and (2) to estimate the point-prevalence of impending neurologic injury secondary to surgical positioning effects. Sixty-nine of 3,806 patients (1.8% showed intraoperative evidence of impending neurologic injury secondary to positioning, prompting interventional repositioning of the patient. The brachial plexus was the site of evolving injury in 65% of these 69 cases. Impending brachial plexopathy was most commonly noted immediately following shoulder taping and the application of counter-traction. Brachial plexus stretch upon neck extension for optimal surgical access and visualization was second in frequency-of-occurrence. Evolving traction injury to the ulnar nerve attributed to tightly-wrapped or malpositioned arms was observed in 16% of alerted cases, whereas evolving spinal cord injury following neck extension accounted for an additional 19%. This study highlights the role of tceMEP and ulnar nerve SSEP monitoring for detecting emerging peripheral nerve injury secondary to positioning in preparation for and during anterior cervical spine surgery. [ABSTRACT FROM AUTHOR]

Objective: To describe a unique morphologic feature of the bilateral posterior tibial nerve cortical somatosensory evoked potential, the S-wave, which varies systematically with propofol infusion rate and which appears to be useful in guiding adequate propofol concentration levels during spine surgery.Methods: Two illustrative cases were selected from a pool of 15,000 pediatric and adult patients (ages 8-85 years) who were undergoing corrective spine surgery in operating rooms of university and community hospitals. Anesthesia was maintained with a continuous intravenous infusion of propofol (125-225 microg/kg/min) along with intermittent boluses of narcotic and midazolam (1.0-2.0 mg) as needed. Characteristic metamorphosis of the bilateral posterior tibial nerve cortical somatosensory evoked potential, highlighted by the emergence of an additional middle-latency component labeled the S-wave, served as a neurophysiological marker of "light" propofol anesthesia prompting elevation of propofol infusion rate or bolus injection.Results: The S-wave was routinely abolished with increased propofol infusion rate or bolus injection. In all instances increased propofol concentration levels produced a characteristic morphologic change in the posterior tibial nerve cortical somatosensory evoked potential consistent with a return to adequate anesthetic depth. Selected cases presented herein compare the S-wave technique to BIS and illustrate the usefulness of the S-wave in identifying inadequate depth of propofol anesthesia.Conclusions: The bilateral posterior tibial nerve cortical somatosensory evoked potential changes its morphology in predictable fashion with decreased depth of propofol anesthesia, allowing for anticipation of imminent anesthetic "lightening." It serves as a useful cross-check to Bispectral Index (BIS) or other "level of consciousness" EEG-based algorithms for monitoring depth of propofol anesthesia during prolonged corrective spine surgery. [ABSTRACT FROM AUTHOR]