Temporary Mechanical Circulatory Support for Transcatheter Aortic Valve Replacement.

INTRODUCTION: This study aimed to characterize the use of temporary mechanical circulatory support (tMCS) among patients undergoing transcatheter aortic valve replacement (TAVR) using a nationally representative database. MATERIALS AND METHODS: The 2012-2018 National Inpatient Sample was queried for adult patients who underwent isolated TAVR. The tMCS group was comprised of those who required extracorporeal membrane oxygenation, percutaneous ventricular assist device, or intra-aortic balloon pump during index hospitalization. We evaluated temporal trends in the utilization of tMCS using Cuzick's test. Furthermore, a multivariable logistic regression was used to identify factors associated with tMCS use and its impact on in-hospital mortality, selected complications, and nonhome discharge. RESULTS: Of an estimated 215,925 patients who underwent TAVR, 3085 (1.4%) required tMCS during their hospital course. The most common modality of tMCS was intra-aortic balloon pump (49%), followed by extracorporeal membrane oxygenation (27%) then percutaneous ventricular assist device (18%). Seven percent of tMCS patients were supported by > 1 device. The annual incidence of tMCS usage decreased over the study period, from 3% in 2012 to 1% in 2018 (P-trend < 0.01). Nonelective admission, congestive heart failure, coagulopathy, and liver disease were strong independent predictors of requiring tMCS. Patients requiring tMCS had a 31.8% in-hospital mortality rate (adjusted odds ratio = 23, 95% confidence interval 18.5-28.5), longer length of stay (9 d versus 3, P < 0.001), and higher costs ($84,600 versus $48,100, P < 0.001) than those who did not. CONCLUSIONS: The use of tMCS during TAVR has decreased over time but remains associated with a 23-fold increased mortality rate and significant clinical and resource utilization burden.

Does Targeted Temperature Management Improve Neurological Outcome in Extracorporeal Cardiopulmonary Resuscitation (ECPR)?

PURPOSE: Targeted temperature management (TTM) is a standard of care in patients after cardiac arrest for neuroprotection. Currently, the effectiveness and efficacy of TTM after extracorporeal cardiopulmonary resuscitation (ECPR) is unknown. We aimed to compare neurological and survival outcomes between TTM vs non-TTM in patients undergoing ECPR for refractory cardiac arrest. METHODS: We searched PubMed and 5 other databases for randomized controlled trials and observational studies reporting neurological outcomes or survival in adult patients undergoing ECPR with or without TTM. Good neurological outcome was defined as cerebral performance category <3. Two independent reviewers extracted the data. Random-effects meta-analyses were used to pool data. RESULTS: We included 35 studies (n = 2,643) with the median age of 56 years (interquartile range [IQR]: 52-59). The median time from collapse to ECMO cannulation was 58 minutes (IQR: 49-82) and the median ECMO duration was 3 days (IQR: 2.0-4.1). Of 2,643, 1,329 (50.3%) patients received TTM and 1,314 (49.7%) did not. There was no difference in the frequency of good neurological outcome at any time between TTM (29%, 95% confidence interval [CI]: 23%-36%) vs. without TTM (19%, 95% CI: 9%-31%) in patients with ECPR (P = 0.09). Similarly, there was no difference in overall survival between patients with TTM (30%, 95% CI: 22%-39%) vs. without TTM (24%, 95% CI: 14%-34%) (P = 0.31). A cumulative meta-analysis by publication year showed improved neurological and survival outcomes over time. CONCLUSIONS: Among ECPR patients, survival and neurological outcome were not different between those with TTM vs. without TTM. Our study suggests that neurological and survival outcome are improving over time as ECPR therapy is more widely used. Our results were limited by the heterogeneity of included studies and further research with granular temperature data is necessary to assess the benefit and risk of TTM in ECPR population.

Population Characteristics and Markers for Withdrawal of Life-Sustaining Therapy in Patients on Extracorporeal Membrane Oxygenation.

OBJECTIVE: As survival with extracorporeal membrane oxygenation (ECMO) therapy improves, it is important to study patients who do not survive secondary to withdrawal of life-sustaining therapy (WLST). The purpose of the present study was to determine the population and clinical characteristics of those who experienced short latency to WLST. DESIGN: Retrospective cohort study. SETTING: Single academic hospital center. PARTICIPANTS: Adult ECMO patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: During the study period, 150 patients (mean age 54.8 ± 15.9 y, 43.3% female) underwent ECMO (80% venoarterial ECMO and 20% venovenous ECMO). Seventy-three (48.7%) had WLST from ECMO support (median five days), and 33 of those (45.2%) had early WLST (≤five days). Patients who underwent WLST were older (60.3 ± 15.3 y v 49.6 ± 14.7 y; p < 0.001) than those who did not undergo WLST and had greater body mass index (31.7 ± 7.6 kg/m2v 28.3 ± 5.5 kg/m2; p = 0.002), longer ECMO duration (six v four days; p = 0.01), and higher Acute Physiology and Chronic Health Evaluation (25 v 21; p < 0.001) and Sequential Organ Failure Assessment (12 v 11; p = 0.037) scores. Family request frequently (91.7%) was cited as part of the WLST decision. WLST patients experienced more chaplaincy (89% v 65%; p < 0.001), palliative care consults (53.4% v 29.9%; p = 0.003), and code status change (do not resuscitate: 83.6% v 7.8%; p < 0.001). CONCLUSIONS: Nearly 50% of ECMO patients underwent WLST, with approximately 25% occurring in the first 72 hours. These patients were older, sicker, and experienced a different clinical context. Unlike with other critical illnesses, neurologic injury was not a primary reason for WLST in ECMO patients.

Continuous Electroencephalography Markers of Prognostication in Comatose Patients on Extracorporeal Membrane Oxygenation.

BACKGROUND: We aimed to identify continuous electroencephalogram (cEEG) markers associated with survival and death in patients with extracorporeal membrane oxygenation (ECMO) support under standardized sedation cessation protocol. METHODS: Prospectively collected records of adult patients (age ≥ 18 years) who were started on ECMO support in July 2016 to December 2020 at a single tertiary center were analyzed. cEEGs were performed on patients on the basis of inclusion and exclusion criteria. Patients receiving sedation that affect cEEG reactivity at the start of cEEG recording, including propofol, ketamine, or benzodiazepines, were excluded. We allowed fentanyl and dexmedetomidine during cEEG monitoring. cEEGs were evaluated for frequency, amplitude, variability, reactivity, and state changes. RESULTS: Of 290 patients, 40 underwent cEEG in the absence of confounding sedation (median age 60 years, 85% venoarterial-ECMO, 15% venovenous-ECMO). The median length of ECMO support and analyzable cEEG were 143 h and 24 h, respectively. A total of 27 patients underwent withdrawal of life-sustaining therapies (WOLST) during ECMO support. Of the 13 who weaned off ECMO, 9 underwent WOLST later in the hospitalization and 4 survived at hospital discharge. Decisions of WOLST were not influenced by cEEG features' results. Proportions of present EEG reactivity, present state changes, and fair/good variability were significantly higher in patients who survived compared with those who died (odds ratios infinity, infinity, and 13.57, respectively; p values < 0.001, < 0.001, and 0.0299, respectively). Sensitivity and specificity for survival at discharge were 100% and 91.67% for intact reactivity, 100% and 97.20% for present state changes, and 75% and 83.3% for fair/good variability. CONCLUSIONS: Although future multicenter studies with larger patient cohorts are certainly warranted, we were able to validate the feasibility of protocolized sedation cessation and cEEG analyses in the absence of a confounding effect from sedating medications. Moreover, we demonstrate some evidence that cEEG features of intact reactivity, present state changes, and fair/good variability in comatose patients on ECMO may be associated with survival at hospital discharge.

Duration of Hyperoxia and Neurologic Outcomes in Patients Undergoing Extracorporeal Membrane Oxygenation.

OBJECTIVES: To evaluate the impact of duration of hyperoxia on neurologic outcome and mortality in patients undergoing venoarterial extracorporeal membrane oxygenation. DESIGN: A retrospective analysis of venoarterial extracorporeal membrane oxygenation patients admitted to the Johns Hopkins Hospital. The primary outcome was neurologic function at discharge defined by modified Rankin Scale, with a score of 0-3 defined as a good neurologic outcome, and a score of 4-6 defined as a poor neurologic outcome. Multivariable logistic regression analysis was performed to evaluate the association between hyperoxia and neurologic outcomes. SETTING: The Johns Hopkins Hospital Cardiovascular ICU and Cardiac Critical Care Unit. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We measured first and maximum Pao2 values, area under the curve per minute over the first 24 hours, and duration of mild, moderate, and severe hyperoxia. Of 132 patients on venoarterial extracorporeal membrane oxygenation, 127 (96.5%) were exposed to mild hyperoxia in the first 24 hours. Poor neurologic outcomes were observed in 105 patients (79.6%) (102 with vs 3 without hyperoxia; p = 0.14). Patients with poor neurologic outcomes had longer exposure to mild (19.1 vs 15.2 hr; p = 0.01), moderate (14.6 vs 9.2 hr; p = 0.003), and severe hyperoxia (9.1 vs 4.0 hr; p = 0.003). In a multivariable analysis, patients with worse neurologic outcome experienced longer durations of mild (adjusted odds ratio, 1.10; 95% CI, 1.01-1.19; p = 0.02), moderate (adjusted odds ratio, 1.12; 95% CI, 1.04-1.22; p = 0.002), and severe (adjusted odds ratio, 1.19; 95% CI, 1.06-1.35; p = 0.003) hyperoxia. Additionally, duration of severe hyperoxia was independently associated with inhospital mortality (adjusted odds ratio, 1.18; 95% CI, 1.08-1.29; p < 0.001). CONCLUSIONS: In patients undergoing venoarterial extracorporeal membrane oxygenation, duration and severity of early hyperoxia were independently associated with poor neurologic outcomes at discharge and mortality.

Risk Factors of Ischemic and Hemorrhagic Strokes During Venovenous Extracorporeal Membrane Oxygenation: Analysis of Data From the Extracorporeal Life Support Organization Registry.

OBJECTIVES: Stroke is commonly reported in patients receiving venovenous extracorporeal membrane oxygenation, but risk factors are not well described. We sought to determine preextracorporeal membrane oxygenation and on-extracorporeal membrane oxygenation risk factors for both ischemic and hemorrhagic strokes in patients with venovenous extracorporeal membrane oxygenation support. DESIGN: Retrospective analysis. SETTING: Data reported to the Extracorporeal Life Support Organization by 366 extracorporeal membrane oxygenation centers from 2013 to 2019. PATIENTS: Patients older than 18 years supported with a single run of venovenous extracorporeal membrane oxygenation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 15,872 venovenous extracorporeal membrane oxygenation patients, 812 (5.1%) had at least one type of acute brain injury, defined as ischemic stroke, hemorrhagic stroke, or brain death. Overall, 215 (1.4%) experienced ischemic stroke and 484 (3.1%) experienced hemorrhagic stroke. Overall inhospital mortality was 36%, but rates were higher in those with ischemic or hemorrhagic stroke (68% and 73%, respectively). In multivariable analysis, preextracorporeal membrane oxygenation pH (adjusted odds ratio = 0.10; 95% CI, 0.03-0.35; p < 0.001), hemolysis (adjusted odds ratio = 2.27; 95% CI, 1.22-4.24; p = 0.010), gastrointestinal hemorrhage (adjusted odds ratio = 2.01; 95% CI 1.12-3.59; p = 0.019), and disseminated intravascular coagulation (adjusted odds ratio = 3.61; 95% CI, 1.51-8.66; p = 0.004) were independently associated with ischemic stroke. Pre-extracorporeal membrane oxygenation pH (adjusted odds ratio = 0.28; 95% CI, 0.12-0.65; p = 0.003), preextracorporeal membrane oxygenation Po2 (adjusted odds ratio = 0.96; 95% CI, 0.93-0.99; p = 0.021), gastrointestinal hemorrhage (adjusted odds ratio = 1.70; 95% CI, 1.15-2.51; p = 0.008), and renal replacement therapy (adjusted odds ratio=1.57; 95% CI, 1.22-2.02; p < 0.001) were independently associated with hemorrhagic stroke. CONCLUSIONS: Among venovenous extracorporeal membrane oxygenation patients in the Extracorporeal Life Support Organization registry, approximately 5% had acute brain injury. Mortality rates increased two-fold when ischemic or hemorrhagic strokes occurred. Risk factors such as lower pH and hypoxemia during the pericannulation period and markers of coagulation disturbances were associated with acute brain injury. Further research on understanding preextracorporeal membrane oxygenation and on-extracorporeal membrane oxygenation risk factors and the timing of acute brain injury is necessary to develop appropriate prevention and management strategies.

Decreased Nutritional Risk Index is associated with mortality after heart transplantation.

INTRODUCTION: Validated scoring tools, such as the Nutritional Risk Index (NRI), can aid clinicians in quantifying the degree of malnourishment in patients prior to an operation. We evaluated the association between NRI and outcomes after heart transplantation. METHODS: The United Network for Organ Sharing (UNOS) database was used to identify adult patients (age > 18) undergoing heart transplantation between 1987 and 2016. NRI was calculated and categorized into previously established groupings representing severity of malnutrition. Multivariate Cox proportional hazards modeling were used to assess the primary outcome of all-cause mortality. RESULTS: A total of 25,236 patients were included in the analysis. Most patients (75.4%) were male. Malnourishment was absent (NRI ≥ 100) in 11,022 (44%) patients, while 2,898 (12%) were mildly malnourished (97.5 ≤ NRI < 100), 8,685 (34%) were moderately malnourished (83.5 ≤ NRI < 97.5), and 2,631 (10%) were severely malnourished (NRI < 83.5). Moderate-to-severe malnutrition was associated with increased mortality (HR = 1.18, p < .001, 95%CI: 1.13-1.24), and post-transplant renal failure requiring dialysis (OR: 1.13, p < .001, 95%CI: 1.03-1.23). CONCLUSION: Malnourishment determined by NRI is independently associated with mortality and post-transplant dialysis after heart transplant. This is the largest study of NRI in heart transplant recipients.

The 2018 adult heart allocation policy change benefits low-volume transplant centers.

INTRODUCTION: The effect of the 2018 adult heart allocation policy change at an institution-level remains unclear. The present study assessed the impact of the policy change by transplant center volume. METHODS: The United Network for Organ Sharing database was queried for all adults undergoing isolated heart transplantation from November 2016 to September 2020. Era 1 was defined as the period before the policy change and Era 2 afterwards. Hospitals were divided into low-(LVC) medium-(MVC) and high-volume (HVC) tertiles based on annual transplant center volume. Competing-risks regressions were used to determine changes in waitlist death/deterioration, while post-transplant mortality was assessed using multivariable Cox proportional-hazards models. RESULTS: A total of 3531 (47.0%) patients underwent heart transplantation in Era 1 and 3988 (53.0%) in Era 2. At LVC, Era 2 patients were less likely to experience death/deterioration on the waitlist (subhazard ratio .74, 95% CI .63-.88), while MVC and HVC patients experienced similar waitlist death/deterioration across eras. After adjustment, transplantation in Era 2 was associated with worse 1-year mortality at MVC (hazard ratio, HR, 1.42 95% CI 1.02-1.96) and HVC (HR 1.42, 95% CI 1.02-1.98) but not at LVC. CONCLUSION: Early analysis shows that LVC may be benefitting under the new allocation scheme.

A Comprehensive Review of Risk Factor, Mechanism, and Management of Left Ventricular Assist Device-Associated Stroke.

The use of left ventricular assist devices (LVADs) has been increasing in the last decade, along with the number of patients with advanced heart failure refractory to medical therapy. Ischemic stroke and intracranial hemorrhage remain the leading causes of morbidity and mortality in LVAD patients. Despite the common occurrence and the significant outcome impact, underlying mechanisms and management strategies of stroke in LVAD patients are controversial. In this article, we review our current knowledge on pathophysiology and risk factors of LVAD-associated stroke, outline the diagnostic approach, and discuss treatment strategies.

The Use of Cerebral NIRS Monitoring to Identify Acute Brain Injury in Patients With VA-ECMO.

Acute brain injury (ABI) increases morbidity and mortality in patients with veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Optimal neurologic monitoring methods have not been well-explicated. We studied the use of Near-infrared Spectroscopy (NIRS) to monitor cerebral regional oxygenation tissue saturation (rSO2) and its relation to ABI in VA-ECMO. In this prospective, observational cohort study of 39 consecutive patients, we analyzed the ability of rSO2 values from continuous bedside NIRS monitoring to predict ABI during VA-ECMO support. ABI occurred in 24 (61.5%) patients. Those with ABI had a lower pre-ECMO Glasgow Coma Scale, more blood product transfusions of pRBCs and FFP, and higher APACHEII score. Baseline rSO2 values were not significantly different between cohorts (54.25 vs 58.50, p = 0.260), while the minimum rSO2 value was lower for patients who experienced an ABI than those who did not (39.75 vs 44.50, p = 0.039). In patients with ABI, 21 (87.5%) had a drop in rSO2 of 25% from baseline, compared to only 7 (46.7%) patients without ABI (p = 0.017). By ROC analysis, we found that desaturations with >25% drop from the baseline rSO2 on VA-ECMO exhibited 86% sensitivity and 55% specificity to predict ABI, with an area under the curve of 0.68. Patients with ABI were more likely to have withdrawal of life sustaining therapy (17 vs 5, p = 0.049), while neurologic outcome and mortality were not statistically different between patients with or without ABI. Our results support that cerebral NIRS is a useful, real-time bedside neuromonitoring tool to detect ABI in VA-ECMO patients. A >25% drop from the baseline was sensitive in predicting ABI occurrence. Further research is needed to assess how to implement this knowledge to utilize NIRS in developing appropriate intervention strategy in VA-ECMO patients.

Time-Resolved Echo-Particle Image/Tracking Velocimetry Measurement of Interactions Between Native Cardiac Output and Veno-Arterial ECMO Flows.

Determination of optimal hemodynamic and pressure-volume loading conditions for patients undergoing veno-arterial extracorporeal membrane oxygenation (VA-ECMO) would benefit from understanding the impact of ECMO flow rates (QE) on the native cardiac output in the admixing zone, i.e., aortic root. This study characterizes the flow in the aortic root of a pig with severe myocardial ischemia using contrast-enhanced ultrasound particle image/tracking velocimetry (echo-PIV/PTV). New methods for data preprocessing are introduced, including autocontouring to remove surrounding tissues, followed by blind deconvolution to identify the centers of elongated bubble traces in images with low signal to noise ratio. Calibrations based on synthetic images show that this procedure increases the number of detected bubbles and reduces the error in their locations by 50%. Then, an optimized echo-PIV/PTV procedure, which integrates image enhancement with velocity measurements, is used for characterizing the time-resolved two-dimensional (2D) velocity distributions. Phase-averaged and instantaneous flow fields show that the ECMO flow rate influences the velocity and acceleration of the cardiac output during systole, and secondary flows during diastole. When QE is 3.0 L/min or higher, the cardiac ejection velocity, phase interval with open aortic valve, velocity-time integral (VTI), and mean arterial pressure (MAP) increase with decreasing QE, all indicating sufficient support. For lower QE, the MAP and VTI decrease as QE is reduced, and the deceleration during transition to diastole becomes milder. Hence, for this specific case, the optimal ECMO flow rate is 3.0 L/min.

Brain magnetic resonance imaging in adult survivors of extracorporeal membrane oxygenation.

Despite the common occurrence of neurologic complications in patients with extracorporeal membrane oxygenation (ECMO), data on magnetic resonance imaging (MRI) findings in adult ECMO are limited. We aimed to describe the MRI findings of patients after ECMO cannulation. Records of patients who underwent ECMO from September 2017 to June 2019 were reviewed. MRI studies were performed using multiplanar sequences consisting of T1-, T2-weighted, fluid attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), and susceptibility weighted images (SWI). Of the 78 adult patients who underwent ECMO, 26 (33%) survived. Of 26, eight patients (31%) had MRI studies, with a median age of 47 years (interquartile range [IQR]: 25-57). The median ECMO support time was 8 days (IQR: 4-25) and the median time from decannulation to MRI was 12 days (IQR: 1-34). Five (63%) of eight patients had ischemic infarcts; 4 (50%) had cerebral microhemorrhage; 2 (25%) had intracranial hemorrhage; and 1 (13%) had thoracic cord ischemic infarct. There were no patients with normal MRI. All patients underwent transcranial Doppler (TCD). Four of 8 (50%) showed presence of microemboli with TCD; 3 of 4 (75%) had ischemic infarcts; and 1 of 4 (25%) had presence of multiple cerebral microhemorrhages on MRI. All ischemic infarcts had diffuse pattern of punctate to small lesions for ECMO survivors. The location of cerebral microhemorrhages included lobar (n = 4, 100%), deep (n = 2, 50%), and both (n = 2, 50%). Of the MRI studies, cerebrovascular related lesions were the most frequent, with punctate ischemic infarct being the most common type that may be associated with TCD microemboli. The results of the study suggest that subclinical cerebral lesions are commonly found in patients with ECMO support. Further research is needed to understand long-term effect of these cerebral lesions.

Therapeutic drug monitoring of valproic acid in extracorporeal membrane oxygenation.

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) is a life-saving therapy for those in cardiopulmonary failure, including post-cardiac arrest. Despite a high volume of ECMO patients using anti-seizure medication, there is a paucity of data concerning the dosing, levels, and clinical scenarios for their use. CASE REPORT: We present three cases of ECMO patients post-PEA arrest who were on valproic acid (VPA) for treatment of seizure and/or myoclonus. The total and free levels of VPA are reported. DISCUSSION: The trough levels are consistent throughout therapy, suggesting VPA is not significantly removed by the ECMO circuitry. Although the total serum levels remained below the toxic range, the free level was elevated in two patients. These patients did not develop signs of toxicity. CONCLUSION: VPA may be an effective anti-seizure medication in ECMO patients. Free VPA levels should be more readily available to better quantify efficacy or toxicity, especially in ECMO patients.

Modifiable Risk Factors and Mortality From Ischemic and Hemorrhagic Strokes in Patients Receiving Venoarterial Extracorporeal Membrane Oxygenation: Results From the Extracorporeal Life Support Organization Registry.

OBJECTIVES: Although acute brain injury is common in patients receiving extracorporeal membrane oxygenation, little is known regarding the mechanism and predictors of ischemic and hemorrhagic stroke. We aimed to determine the risk factors and outcomes of each ischemic and hemorrhagic stroke in patients with venoarterial extracorporeal membrane oxygenation support. DESIGN: Retrospective analysis. SETTING: Data reported to the Extracorporeal Life Support Organization by 310 extracorporeal membrane oxygenation centers from 2013 to 2017. PATIENTS: Patients more than 18 years old supported with a single run of venoarterial extracorporeal membrane oxygenation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 10,342 venoarterial extracorporeal membrane oxygenation patients, 401 (3.9%) experienced ischemic stroke and 229 (2.2%) experienced hemorrhagic stroke. Reported acute brain injury during venoarterial extracorporeal membrane oxygenation decreased from 10% to 6% in 5 years. Overall in-hospital mortality was 56%, but rates were higher when ischemic stroke and hemorrhagic stroke were present (76% and 86%, respectively). In multivariable analysis, lower pre-extracorporeal membrane oxygenation pH (adjusted odds ratio, 0.21; 95% CI, 0.09-0.49; p < 0.001), higher PO2 on first day of extracorporeal membrane oxygenation (adjusted odds ratio, 1.01; 95% CI, 1.00-1.02; p = 0.009), higher rates of extracorporeal membrane oxygenation circuit mechanical failure (adjusted odds ratio, 1.33; 95% CI, 1.02-1.74; p = 0.03), and renal replacement therapy (adjusted odds ratio, 1.49; 95% CI, 1.14-1.94; p = 0.004) were independently associated with ischemic stroke. Female sex (adjusted odds ratio, 1.61; 95% CI, 1.16-2.22; p = 0.004), extracorporeal membrane oxygenation duration (adjusted odds ratio, 1.01; 95% CI, 1.00-1.03; p = 0.02), renal replacement therapy (adjusted odds ratio, 1.81; 95% CI, 1.30-2.52; p < 0.001), and hemolysis (adjusted odds ratio, 1.87; 95% CI, 1.11-3.16; p = 0.02) were independently associated with hemorrhagic stroke. CONCLUSIONS: Despite a decrease in the prevalence of acute brain injury in recent years, mortality rates remain high when ischemic and hemorrhagic strokes are present. Future research is necessary on understanding the timing of associated risk factors to promote prevention and management strategy.

Understanding Characteristics of Acute Brain Injury in Adult Extracorporeal Membrane Oxygenation: An Autopsy Study.

OBJECTIVES: Current studies lack information on characteristics of acute brain injury in patients with extracorporeal membrane oxygenation. We sought to characterize the types, timing, and risk factors of acute brain injury in extracorporeal membrane oxygenation. DESIGN: Retrospective analysis. SETTING: We reviewed the extracorporeal membrane oxygenation patients who had undergone brain autopsy with gross and microscopic examinations from January 2009 to December 2018 from a single tertiary center. PATIENTS: Twenty-five patients (median age 53 yr) had postmortem brain autopsy. INTERVENTIONS: Description and analysis of neuropathologic findings. MEASUREMENT AND MAIN RESULTS: Of 25, 22 had venoarterial extracorporeal membrane oxygenation (88%) (nine cardiac arrest; 13 cardiogenic shock) and three had venovenous extracorporeal membrane oxygenation cannulation (12%). The median extracorporeal membrane oxygenation support time was 96 hours (interquartile range, 26-181 hr). The most common acute brain injury was hypoxic-ischemic brain injury (44%), followed by intracranial hemorrhage (24%), and ischemic infarct (16%). Subarachnoid hemorrhage (20%) was the most common type of intracranial hemorrhage, followed by intracerebral hemorrhage (8%), and subdural hemorrhage (4%). Only eight patients (32%) were without acute brain injury after extracorporeal membrane oxygenation. The most common involved location for hypoxic-ischemic brain injury was cerebral cortices (82%) and cerebellum (55%). The pattern of ischemic infarct was territorial in cerebral cortices. The risk factors for acute brain injury included hypertension history (11 vs 1; p = 0.01), preextracorporeal membrane oxygenation antiplatelet use (7 vs 0; p = 0.03), and a higher day 1 lactate level (10.0 vs 5.1; p = 0.02). Patients with hypoxic-ischemic brain injury had more hypertension (8 vs 4; p = 0.047), a higher day 1 lactate level (12.6 vs 5.8; p = 0.02), and a lower pH level (7.09 vs 7.24; p = 0.027). Extracorporeal membrane oxygenation duration, cannulation methods, hemoglobin level, coma, renal impairment, and hepatic impairment were not associated with acute brain injury. CONCLUSIONS: In the population who underwent postmortem neuropathologic evaluation, 68% of extracorporeal membrane oxygenation nonsurvivors developed acute brain injury. Hypoxic-ischemic brain injury was the most common type of injury suggesting that patients sustained acute brain injury as a consequence of cardiogenic shock and cardiac arrest. Further research with a systematic neurologic monitoring is necessary to define the timing of acute brain injury in patients with extracorporeal membrane oxygenation.

Racial disparities among patients on venovenous extracorporeal membrane oxygenation in the pre-Coronavirus Disease 2019 and Coronavirus Disease 2019 eras: A retrospective registry review.

Objectives: Although many studies have addressed such disparities caused by COVID-19, to our knowledge, no study has focused on the association of race on outcomes for patients with COVID-19 requiring venovenous extracorporeal membrane oxygenation support. The goal of this study was to assess association of race on death and duration on venovenous extracorporeal membrane oxygenation in both the pre-COVID-19 and COVID-19 eras. Methods: We retrospectively reviewed the Extracorporeal Life Support Organization registry and included adults (≥18 years) who required venovenous extracorporeal membrane oxygenation between January 2019 and April 2021. We performed descriptive statistics and multivariable logistic regression. Our primary outcomes were death and extracorporeal membrane oxygenation duration. Results: A total of 7477 patients were included after excluding 340 patients (4.3%) who were missing race data. In the COVID-19 era, 1474 of 2777 COVID-19-positive patients (53.1%) died. Our regression model suggested somewhat of a protective effect on death for Black and multiple race patients. Additionally, a diagnosis of COVID-19 and patients in the COVID-19 era in general, irrespective of COVID-19 diagnosis, had higher odds of death. Hispanic patients had the longest average venovenous extracorporeal membrane oxygenation run times. Conclusions: Our study using data from the international Extracorporeal Life Support Organization Registry provides updated data on patients supported with venovenous extracorporeal membrane oxygenation in the pre-COVID-19 and COVID-19 eras between 2019 and 2021 with a focus on race. Patients in the COVID-19 era group also had higher mortality compared with those in the pre-COVID-19 era even after being adjusted for COVID-19 diagnosis. Black and multiple races appeared somewhat protective in terms of death. Hispanic race was associated with longer venovenous extracorporeal membrane oxygenation duration.

Sex-Related Differences in Utilization and Outcomes of Extracorporeal Cardio-Pulmonary Resuscitation for Refractory Cardiac Arrest.

Sparse data exist on sex-related differences in extracorporeal cardiopulmonary resuscitation (ECPR) for refractory cardiac arrest (rCA). We explored the role of sex on the utilization and outcomes of ECPR for rCA by retrospective analysis of the Extracorporeal Life Support Organization (ELSO) International Registry. The primary outcome was in-hospital mortality. Exploratory outcomes were discharge disposition and occurrence of any specific extracorporeal membrane oxygenation (ECMO) complications. From 1992 to 2020, a total of 7,460 adults with ECPR were identified: 30.5% women; 69.5% men; 55.9% Whites, 23.7% Asians, 8.9% Blacks, and 3.8% Hispanics. Women's age was 50.4 ± 16.9 years (mean ± standard deviation) and men's 54.7 ± 14.1 (p < 0.001). Ischemic heart disease occurred in 14.6% women vs. 18.5% men (p < 0.001). Overall, 28.5% survived at discharge, 30% women vs. 27.8% men (p = 0.138). In the adjusted analysis, sex was not associated with in-hospital mortality (odds ratio [OR] = 0.93 [confidence interval {CI} = 0.80-1.08]; p = 0.374). Female sex was associated with decreased odds of neurologic, cardiovascular, and renal complications. Despite being younger and having fewer complications during ECMO, women had in-hospital mortality similar to men. Whether these findings are driven by biologic factors or disparities in health care warrants further investigation.

Neuromonitoring detects brain injury in patients receiving extracorporeal membrane oxygenation support.

OBJECTIVE: There is limited evidence on standardized protocols for optimal neurological monitoring methods in patients receiving extracorporeal membrane oxygenation (ECMO). We previously introduced protocolized noninvasive multimodal neuromonitoring using serial neurological examinations, electroencephalography, transcranial Doppler ultrasound, and somatosensory evoked potentials. The purpose of this study was to examine if standardized neuromonitoring is associated with detection of acute brain injury (ABI) and improved patient outcomes. METHODS: A retrospective analysis of ECMO patients who received neurocritical care consultation was performed and outcomes were reviewed. The cohort was stratified according to those who did not receive standardized neuromonitoring (era 1: 2016-2017) and those who received standardized neuromonitoring (era 2: 2017-2020). Multivariable logistic regression was used to evaluate the association between standardized neuromonitoring and ABI. RESULTS: A total of 215 patients (mean age, 54 years; 60% male) underwent ECMO (71% venoarterial-ECMO) in our institution, 70 in era 1 and 145 in era 2. The proportion of patients diagnosed with ABI were 23% in era 1 and 33% in era 2 (P = .12). In multivariable logistic regression, standardized neuromonitoring (odds ratio, 2.24; 95% CI, 1.12-4.48; P = .02) and pre-ECMO cardiac arrest (odds ratio, 2.17; 95% CI, 1.14-4.14; P = .02) were independently associated with ABI. There was a greater proportion of patients with good neurological outcomes when discharged alive in era 2 (54% vs 30%; P = .04). CONCLUSIONS: Standardized neuromonitoring was associated with increased ABIs in ECMO patients. Although neuromonitoring does not prevent ABI from occurring, it might prevent worsening with timely interventions (eg, anticoagulation management, optimizing oxygen delivery and blood pressure), leading to improved neurological outcomes at discharge.

Outcomes of extracorporeal membrane oxygenation following the 2018 adult heart allocation policy.

BACKGROUND: The purpose of the study was to characterize changes in waitlist and post-transplant outcomes of extracorporeal membrane oxygenation (ECMO) patients bridged to heart transplantation under the 2018 adult heart allocation policy. METHODS: All adult patients listed for isolated heart transplantation from August 2016 to December 2020 were identified using the United Network for Organ Sharing database. Patients were stratified into Eras (Era 1 and Era 2) centered around the policy change on October 18, 2018. Competing risk regression was used to evaluate waitlist death or deterioration across Eras. Cox proportional hazards models were used to determine associations between use of ECMO and 1-year post-transplant mortality within each Era. RESULTS: Of 8,902 heart transplants included in analysis, 339 (3.8%) were bridged with ECMO (Era 2: 6.1% vs Era 1: 1.2%, P<0.001). Patients bridged with ECMO in Era 2 were less frequently female (26.0% vs 42.0%, P = 0.02) and experienced shorter waitlist times (5 vs 11 days, P<0.001) along with a lower likelihood of waitlist death or deterioration (subdistribution hazard ratio, 0.45, 95% confidence interval, CI, 0.30-0.68, P<0.001) compared to those in Era 1. Use of ECMO was associated with increased post-transplant mortality at 1-year compared to all other transplants in Era 1 (hazard ratio 3.78, 95% CI 1.88-7.61, P < 0.001) but not Era 2. CONCLUSIONS: Patients bridged with ECMO in Era 2 experience improved waitlist and post-transplant outcomes compared to Era 1, giving credence to the increased use of ECMO under the new allocation policy.

Early withdrawal of life sustaining therapy in extracorporeal cardiopulmonary resuscitation (ECPR): Results from the Extracorporeal Life Support Organization registry.

AIMS: Although extracorporeal cardiopulmonary resuscitation (ECPR) improves survival outcomes in refractory cardiac arrest, morbidity and mortality remain significantly high. Information on causes of death in ECPR is limited; however, some evidence suggests withdrawal of life sustaining therapy (WLST) is a major factor in ECPR-associated mortality. We sought to describe the patients experiencing WLST after ECPR. METHODS: The international Extracorporeal Life Support Organization (ELSO) Registry was retrospectively queried for patients more than 18 years old supported with ECPR who underwent WLST due to family request from 2007 to 2017. These patients were split into groups for descriptive and multivariable analysis: early (WLST < 72 hours from cannulation) and routine WLST. RESULTS: Overall, 411 ECPR patients experienced WLST (median age 42 years IQR = 28-51; 31.7% female) over the 10-year period. 55.5% (n = 228) underwent early WLST with a median ECPR duration of 24 hours (IQR = 7-48) versus routine WLST (median = 147 hours; IQR = 105-238). In multivariable regression analysis, lower arterial blood gas pH (aOR = -3.1; 95% CI = 2.18-2.8; p = 0.04), arterial oxygen saturation (aOR = 1.12; 95% CI = 1.01-1.23; p = 0.02), and higher peak inspiratory pressure (aOR = 0.84; 95% CI = 0.71-1.00; p = 0.05) were independently associated with early WLST. Early WLST patients experienced higher rates of all ECMO-related complications except for infections. CONCLUSIONS: More than half of ECPR patients experienced early WLST within 72 hours. The patients with early WLST had worse markers of severe critical illness at 24 hours and experienced higher rates of complications. Further research should include an appropriate control group to better adjust confounders for ECPR-associated death and focus on prognostication.