Increased task-relevant fMRI responsiveness in comatose cardiac arrest patients is associated with improved neurologic outcomes.

Early prediction of the recovery of consciousness in comatose cardiac arrest patients remains challenging. We prospectively studied task-relevant fMRI responses in 19 comatose cardiac arrest patients and five healthy controls to assess the fMRI's utility for neuroprognostication. Tasks involved instrumental music listening, forward and backward language listening, and motor imagery. Task-specific reference images were created from group-level fMRI responses from the healthy controls. Dice scores measured the overlap of individual subject-level fMRI responses with the reference images. Task-relevant responsiveness index (Rindex) was calculated as the maximum Dice score across the four tasks. Correlation analyses showed that increased Dice scores were significantly associated with arousal recovery (P < 0.05) and emergence from the minimally conscious state (EMCS) by one year (P < 0.001) for all tasks except motor imagery. Greater Rindex was significantly correlated with improved arousal recovery (P = 0.002) and consciousness (P = 0.001). For patients who survived to discharge (n = 6), the Rindex's sensitivity was 75% for predicting EMCS (n = 4). Task-based fMRI holds promise for detecting covert consciousness in comatose cardiac arrest patients, but further studies are needed to confirm these findings. Caution is necessary when interpreting the absence of task-relevant fMRI responses as a surrogate for inevitable poor neurological prognosis.

How to Turn It Down: The Evidence and Opinions Behind Adult Venoarterial Extracorporeal Membrane Oxygenation Weaning.

Adequate and durable recovery in patients supported with venoarterial (VA) extracorporeal membrane oxygenation (ECMO) can be challenging to predict. Extracorporeal membrane oxygenation weaning is the process by which the ECMO flows are decreased to assess if a patient is ready for decannulation. The optimal strategies for deciding who to wean and how to wean VA ECMO remain undefined. A retrospective literature review was performed to understand the evidence supporting current practices in ECMO weaning and in particular patient selection and methods. Most published work and expert opinions agree that once the underlying process has resolved, the minimum required physiologic parameters for weaning from ECMO include: hemodynamic stability and cardiac pulsatility, adequate lung function to support oxygenation and ventilation, and evidence of recovered end organ function. Echocardiography is universally used to assess cardiac function during the weaning process. Currently, there is no consensus regarding who is eligible to wean or how to wean ECMO in adults. We have reviewed the literature to summarize the evidence and expert opinions behind VA ECMO weaning, and give an example of the protocol used at our center. We believe this protocol optimizes patient selection for weaning and helps to predict successful decannulation.

Individualized Multimodal Physiologic Approach to Mechanical Ventilation in Patients With Obesity and Severe Acute Respiratory Distress Syndrome Reduced Venovenous Extracorporeal Membrane Oxygenation Utilization.

OBJECTIVE: To investigate whether individualized optimization of mechanical ventilation through the implementation of a lung rescue team could reduce the need for venovenous extracorporeal membrane oxygenation in patients with obesity and acute respiratory distress syndrome and decrease ICU and hospital length of stay and mortality. DESIGN: Single-center, retrospective study at the Massachusetts General Hospital from June 2015 to June 2019. PATIENTS: All patients with obesity and acute respiratory distress syndrome who were referred for venovenous extracorporeal membrane oxygenation evaluation due to hypoxemic respiratory failure. INTERVENTION: Evaluation and individualized optimization of mechanical ventilation by the lung rescue team before the decision to proceed with venovenous extracorporeal membrane oxygenation. The control group was those patients managed according to hospital standard of care without lung rescue team evaluation. MEASUREMENT AND MAIN RESULTS: All 20 patients (100%) allocated in the control group received venovenous extracorporeal membrane oxygenation, whereas 10 of 13 patients (77%) evaluated by the lung rescue team did not receive venovenous extracorporeal membrane oxygenation. Patients who underwent lung rescue team evaluation had a shorter duration of mechanical ventilation (p = 0.03) and shorter ICU length of stay (p = 0.03). There were no differences between groups in in-hospital, 30-day, or 1-year mortality. CONCLUSIONS: In this hypothesis-generating study, individualized optimization of mechanical ventilation of patients with acute respiratory distress syndrome and obesity by a lung rescue team was associated with a decrease in the utilization of venovenous extracorporeal membrane oxygenation, duration of mechanical ventilation, and ICU length of stay. Mortality was not modified by the lung rescue team intervention.

Left Ventricular Unloading Is Associated With Lower Mortality in Patients With Cardiogenic Shock Treated With Venoarterial Extracorporeal Membrane Oxygenation: Results From an International, Multicenter Cohort Study.

BACKGROUND: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used to treat cardiogenic shock. However, VA-ECMO might hamper myocardial recovery. The Impella unloads the left ventricle. This study aimed to evaluate whether left ventricular unloading in patients with cardiogenic shock treated with VA-ECMO was associated with lower mortality. METHODS: Data from 686 consecutive patients with cardiogenic shock treated with VA-ECMO with or without left ventricular unloading using an Impella at 16 tertiary care centers in 4 countries were collected. The association between left ventricular unloading and 30-day mortality was assessed by Cox regression models in a 1:1 propensity score-matched cohort. RESULTS: Left ventricular unloading was used in 337 of the 686 patients (49%). After matching, 255 patients with left ventricular unloading were compared with 255 patients without left ventricular unloading. In the matched cohort, left ventricular unloading was associated with lower 30-day mortality (hazard ratio, 0.79 [95% CI, 0.63-0.98]; P=0.03) without differences in various subgroups. Complications occurred more frequently in patients with left ventricular unloading: severe bleeding in 98 (38.4%) versus 45 (17.9%), access site-related ischemia in 55 (21.6%) versus 31 (12.3%), abdominal compartment in 23 (9.4%) versus 9 (3.7%), and renal replacement therapy in 148 (58.5%) versus 99 (39.1%). CONCLUSIONS: In this international, multicenter cohort study, left ventricular unloading was associated with lower mortality in patients with cardiogenic shock treated with VA-ECMO, despite higher complication rates. These findings support use of left ventricular unloading in patients with cardiogenic shock treated with VA-ECMO and call for further validation, ideally in a randomized, controlled trial.

The "Flipped Classroom" Model for Teaching in the Intensive Care Unit.

INTRODUCTION: The intensive care unit (ICU) is a dynamic and complex learning environment. The wide range in trainee's experience, specialty training, fluctuations in patient acuity and volume, limitations in trainee duty hours, and additional responsibilities of the faculty contribute to the challenge in providing a consistent experience with traditional educational strategies. The "flipped classroom" is an educational model with the potential to improve the learning environment. In this paradigm, students gain exposure to new material outside class and then use class time to assimilate the knowledge through problem-solving exercises or discussion. The rationale and pedagogical foundations for the flipped classroom are reviewed, practical considerations are discussed, and an example of successful implementation is provided. METHODS: An education curriculum was devised and evaluated prospectively for teaching point-of-care echocardiography to residents rotating in the surgical ICU. RESULTS: Preintervention and postintervention scores of knowledge, confidence, perceived usefulness, and likelihood of use the skills improved for each module. The quality of the experience was rated highly for each of the sessions. CONCLUSION: The flipped classroom education curriculum has many advantages. This pilot study was well received, and learners showed improvement in all areas evaluated, across several demographic subgroups and self-identified learning styles.