Seelhammer, Troy G.

Obesity is common among critically ill adults, but its association with outcomes during venovenous extracorporeal membrane oxygenation (VV ECMO) remains controversial. We evaluated associations of body mass index (BMI) with mortality and Extracorporeal Life Support Organization (ELSO)–defined complications in adults supported with VV ECMO. We conducted a retrospective multicenter cohort study of adults receiving VV ECMO at four centers (2017–2025). The primary outcome was in-hospital mortality; secondary outcomes were ELSO-defined complications. Multivariable logistic regression was adjusted for age, sex, and hospital site; BMI was evaluated as continuous, dichotomized (≥30 vs . <30 kg/m 2 ), and World Health Organization (WHO) obesity class exposures, with interaction testing by coronavirus disease 2019 (COVID-19) status. Among 420 patients (median BMI, 31 kg/m 2 ), in-hospital mortality was 62%. Higher BMI was associated with mortality in non–COVID-19 acute respiratory distress syndrome (ARDS; odds ratio [OR] = 1.06 per 1 kg/m 2 , 95% confidence interval [CI] = 1.02–1.10, p = 0.003) but not in COVID-19 ARDS (OR = 1.00, 95% CI = 0.94–1.05); there was insufficient evidence of interaction between BMI and COVID-19 ( p = 0.07). Higher BMI was associated with renal complications in both groups and infectious complications in non–COVID-19 ARDS (OR = 1.05, 95% CI = 1.02–1.09, p = 0.003). No significant BMI × COVID-19 interaction was detected for any outcomes. These findings do not support an obesity survival paradox during VV ECMO.

In this retrospective cohort study at a quaternary referral hospital, 829 adult patients supported by extracorporeal membrane oxygenation (ECMO) between January 1, 2014, and October 31, 2024, were screened for ventilator-associated pneumonia (VAP). The incidence of VAP in ECMO-supported patients was 17.7 per 1,000 ECMO days (venoarterial [VA] ECMO, 22.1 per 1,000 ECMO days; venovenous [VV] ECMO, 13.8 per 1,000 ECMO days). Median time from ECMO cannulation to diagnosis of VAP was 4 (interquartile range [IQR], 3–8; range 1–84) days. Gram-negative bacteria comprised most respiratory pathogens. A significant increase in minimum ECMO sweep was noted from 2 days before to 1 day after VAP diagnosis (0.79 L/min increase, p = 0.004). Only 38 of 153 patients (24.8%) met National Healthcare Safety Network (NHSN) VAP definitions. After creating a modified VAP definition, which included an ECMO sweep increase of 0.5 L/min as evidence of worsening respiratory status, 78 (51.0%) met the modified definition. Those who met the modified VAP definition had worse in-hospital (60.3% vs. 28.0%, p < 0.001), 30 day (33.3% vs. 17.3%, p = 0.023), and 90 day (53.8% vs. 25.3%, p < 0.001) mortality compared with those who did not meet the modified VAP definition. The incorporation of ECMO parameters into diagnostic criteria may improve detection sensitivity, but further validation is necessary before implementation.

Emerging evidence links veno-venous extracorporeal membrane oxygenation (VV-ECMO) to right ventricular (RV) dysfunction, but the relative contribution of ECMO versus underlying disease progression remains unclear. We conducted a multicenter, retrospective, propensity-matched study including 408 intubated acute respiratory distress syndrome (ARDS) patients who were admitted between January 2020 and October 2024 in a quaternary referral hospital network within the United States and underwent at least two transthoracic echocardiograms (TTEs) after intubation. Using 1:2 propensity score matching, we adjusted for baseline comorbidities, baseline hemoglobin, lactate, and worst PaO 2 /FiO 2 ratio (P/F). Longitudinal echocardiographic changes were analyzed with a cumulative link mixed model (CLMM), evaluating RV size and function as ordinal outcomes. Within 408 patients (112 received ECMO support), propensity matching identified 55 ECMO and 110 non-ECMO patients with balanced baseline characteristics. Among 469 serial echocardiograms, RV size and function worsened more frequently in ECMO patients. In longitudinal modeling, ECMO use alone was not associated with RV dilation ( p = 0.23) or dysfunction ( p = 0.43). However, longer ECMO duration was associated with RV dilation (OR: 1.04 per day, p = 0.004) and dysfunction (odds ratio [OR]: 1.04 per day, p < 0.001). Higher ECMO circuit flow had a trend toward progressive RV dilation and dysfunction but did not reach statistical significance. These findings highlight the need for vigilant RV monitoring during ECMO support.

ABSTRACT Background The Extracorporeal Life Support Organization recommends daily antithrombin monitoring and supplementation to achieve > 50%–80% activity during extracorporeal membrane oxygenation (ECMO). Evidence supporting this practice is uncertain, and whether it confers clinical benefit or harm is unclear. Methods This was a systematic review with meta‐analysis to evaluate the safety and efficacy of antithrombin supplementation during ECMO. We systematically searched databases and registers for studies comparing patients on ECMO who received antithrombin supplementation to those who did not. Random effects meta‐analysis was performed. Risk of bias was independently assessed by two investigators. A priori subgroup and sensitivity analyses were performed to explore reasons for heterogeneity. Results A total of 11 studies were identified. In the pooled meta‐analysis, antithrombin supplementation resulted in no difference in bleeding events (OR 1.38, 95% CI, 0.88–2.17, p = 0.16), thrombotic events (OR 1.57, 95% CI, 0.84–2.90, p = 0.15), or mortality (OR 1.21, 95% CI, 0.81–1.81, p = 0.35) when compared to those who did not receive antithrombin. Subgroup analysis revealed no difference in bleeding events or mortality in pediatric or adult patients; however, pediatric patients that received antithrombin were more likely to experience a thrombotic event (OR 1.70, 95% CI, 1.51–1.91). Sensitivity analysis in only low risk of bias studies confirmed these findings. Conclusions Antithrombin supplementation was not associated with differences in mortality or hemostatic outcomes during ECMO support and may be associated with harm in pediatric patients on ECMO.

Introduction: Cardiopulmonary bypass time (CPBT) and aortic cross-clamp time (AXCT) are independently associated with postoperative morbidity and mortality. However, no universally accepted “optimal” duration exists, as these times are influenced by the complexity of cardiac surgery. ECMO is being increasingly used for cardiogenic shock in patients undergoing cardiotomy, but the impact of CPBT and AXCT on outcomes in this specific population remains unexplored. This study investigates how CPBT and AXCT influence outcomes in cardiotomy patients on ECMO support. Research Question: Do CPBT and AXCT influence mortality and complication rates in cardiotomy patients receiving ECMO support? Methods: We conducted a retrospective chart review (Jan 2020–Dec 2024) across a multidisciplinary North American practice, identifying 623 patients who required ECMO. Of these, 236 (37.8%) received ECMO in the preoperative, intraoperative, or postoperative period of cardiotomy. Patients were grouped by prolonged CPBT (>150 min) vs standard (≤150 min) and prolonged AXCT (>90 min) vs standard (≤90 min). We analyzed outcomes including 30-day mortality, ECMO characteristics, and postoperative complications. Results: Among the 236 patients, the average age was 60.8 years, BMI 37.43 kg/m 2 ; 63% were male, 85% White. Prolonged CPBT and AXCT were associated with higher BMI (p=0.02, 0.03), prior cardiac surgery (p<0.001, 0.006), and combined CABG+AVR procedures (p=0.01, 0.001). Patients with prolonged durations were more likely to require postoperative ECMO (p=0.001, 0.03). Complications such as mediastinal bleeding, AKI requiring CRRT, mediastinitis, bacteremia, and pneumonia, showed significant association with increased CPBT whereas prolonged AXCT was only linked with mediastinal bleeding. CPBT and AXCT durations did not significantly affect 30-day mortality, ICU/hospital stay, ECMO duration, or ventilation duration. Independent predictors of 30-day mortality included pre-/intraoperative IABP use (OR 2.19, 95% CI 1.11–4.30, p=0.023), Impella use (OR 0.20, 95% CI 0.03–0.75, p=0.040), post-op intracranial bleeding (OR 5.46, 95% CI 1.43–23.9, p=0.016), and CRRT-requiring AKI (OR 3.24, 95% CI 1.63–6.57, p<0.001). Conclusion: Prolonged CPBT and AXCT were significantly linked to higher rates of postoperative complications such as mediastinal bleeding, CRRT requiring AKI, mediastinitis, and pneumonia along with increased need for postoperative ECMO support, without significantly affecting mortality.

Refractory anaphylaxis is rare but carries high mortality, particularly when complicated by severe bronchospasm and respiratory failure. We present a 32-year-old individual with food-induced anaphylaxis and profound bronchospasm unresponsive to first- and second-line therapies, resulting in severe hypoxemic and hypercapnic respiratory failure despite mechanical ventilation. Peripheral venovenous extracorporeal membrane oxygenation (VV-ECMO) was emergently initiated, leading to rapid stabilization and full recovery. This case demonstrates the successful use of VV-ECMO as a life-saving bridge in anaphylaxis-induced respiratory failure. This is one of the few reported cases of successful use of VV-ECMO for refractory bronchospasm secondary to anaphylaxis.