Point of care guided coagulation management in adult patients on ECMO: A systematic review and meta-analysis.

BACKGROUND: Despite the advancements in extracorporeal membrane oxygenation (ECMO) technology, balancing the prevention of thrombosis and the risk of bleeding in patients on ECMO is still a significant challenge for physicians. This systematic review and meta-analysis aimed to assess the efficacy and safety of viscoelastic point-of-care (POC)-guided coagulation management in adult patients on ECMO. METHODS: PubMed Medline, Embase, Scopus, Web of Science, and Cochrane Library databases were searched. After quality assessment, meta-analysis was carried out using random effects model, heterogeneity using I2 and publication bias using Doi and Funnel plots. RESULTS: A total of 1718 records were retrieved from the searches. Fifteen studies that enrolled a total of 583 participants met the inclusion criteria. Of those, 3 studies enrolling 181 subjects were eligible for meta-analysis. In patients managed with POC-guided algorithms, the odds were coherently lower for bleeding (OR 0.71, 95%CI 0.36-1.42), thrombosis (OR 0.91, 95%CI 0.32-2.60), and in-hospital mortality (OR 0.54, 95%CI 0.29-1.03), but not for circuit change or failure (OR 1.50, 95%CI 0.59-3.83). However, the differences were not statistically significant due to wide 95%CIs. CONCLUSION: Viscoelastic POC monitoring demonstrates potential benefits for coagulation management in ECMO patients. Future research should focus on standardizing evidence to improve clinical decision-making. REGISTRATION: The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) with registration ID CRD42023486294.

Isoproterenol Improves Hemodynamics And Right Ventricle-Pulmonary Artery Coupling After Heart Transplantation.

BACKGROUND: Right ventricular failure (RVF) is a major cause of early mortality after heart transplantation (HT). Isoproterenol has chronotropic, inotropic, and vasodilatory properties which might improve right ventricle function in this setting. We aimed to investigate the hemodynamic effects of isoproterenol on patients with post-HT RVF. METHODS: We conducted a one-year retrospective observational study including patients receiving isoproterenol and dobutamine for early RVF after HT. A comprehensive multiparametric hemodynamic evaluation was performed successively at three times: no isoproterenol, low doses: 0.025 µg/kg/min and high doses: 0.05 µg/kg/min (henceforth respectively called no-iso, low-iso and high-iso). RESULTS: From June 2022 to June 2023, 25 patients, median [IQR25-75] age 54 [38-61] years, were included. Before isoproterenol introduction, all patients received dobutamine and 15 (60%) were on veno-arterial extracorporeal membrane oxygenation. Isoproterenol significantly increased heart rate from 84 [77-99] (no-iso) to 91 [88-106] (low-iso) and 102 [90-122] bpm (high-iso, p<0.001). Similarly, cardiac index raised from 2.3 [1.4-3.1] to 2.7 [1.8-3.4] and 3 [1.9-3.7] l/min/m2 (p<0.001) with concomitant increase of indexed stroke volume (28 [17-34] to 31 [20-34] and 33 [23-35] mL/m2, p<0.05). Effective pulmonary arterial elastance and pressures were not modified by isoproterenol. Pulmonary vascular resistance tended to decrease from 2.9 (1.4-3.6) WU to 2.3 (1.3-3.5) WU, p=0.06. Right ventricular ejection fraction/systolic PAP evaluating RV-PA coupling increased after isoproterenol from 0.8 to 0.9 and 1 %.mmHg-1 (p=0.001). CONCLUSIONS: In post-HT RVF, isoproterenol exhibits chronotropic and inotropic effects, thereby improving RV-PA coupling and resulting in a clinically relevant increase in the cardiac index.

Recurrent ventilator-associated pneumonia in severe Covid-19 ARDS patients requiring ECMO support.

OBJECTIVE: To describe ventilator-associated pneumonia (VAP) recurrence in COVID-19 patients requiring extracorporeal membrane oxygenation (ECMO) support, and to evaluate the impact of antimicrobial treatment duration of the first VAP episode on VAP recurrence. METHODS: Adult patients with COVID-19 severe pneumonia on ECMO admitted between March 2020 and January 2022 were retrospectively included. Primary outcome was incidence of VAP recurrence, and secondary outcome was the impact of duration of antimicrobial treatment on VAP recurrence. RESULTS: Among the 252 included patients, 226 (90%) developed a first VAP. Sixteen had lung abscess and were excluded, leaving 210 patients. VAP recurrence occurred in 172 patients (82%), with a median (IQR) time from first VAP to recurrence of 10 (7-13) days. Pseudomonas aeruginosa and Enterobacteriaceae were respectively responsible for 28% and 52% of first VAP, and 51% and 62% of first recurrence episodes. Among the 210 patients with a first VAP, 158 (75%) received a short course of antibiotics [< 8 days, median (IQR) duration 6 (5-7) days] and 52 (25%) received a prolonged course of antibiotics [≥ 8 days, median (IQR) duration 9 (8-10) days]. Estimated cumulative incidence of VAP recurrence, taking into account death and extubation as competing risks, was not different in patients with short- and prolonged-antimicrobial treatment. CONCLUSIONS: In patients with severe Covid-19-ARDS requiring ECMO support, VAP recurrence occurs frequently, with Enterobacteriaceae and Pseudomonas aeruginosa as predominant causative microorganisms. An antimicrobial treatment of ≥ 8 days for the treatment of first VAP episode did not reduce the risk of VAP recurrence, as compared to shorter duration.

Venoarterial extracorporeal membrane oxygenation in immunocompromised patients with cardiogenic shock: a cohort study and propensity-weighted analysis.

PURPOSE: The outcomes of immunocompromised patients with cardiogenic shock treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO) are seldom documented, making ECMO candidacy decisions challenging. This study aims (1) to report outcomes of immunocompromised patients treated with VA-ECMO, (2) to identify pre-ECMO predictors of 90-day mortality, (3) to assess the impact of immunodepression on 90-day mortality, and (4) to describe the main ECMO-related complications. METHODS: This is a retrospective, propensity-weighted study conducted in two French experienced ECMO centers. RESULTS: From January 2006 to January 2022, 177 critically ill immunocompromised patients (median (interquartile range, IQR) age 49 (32-60) years) received VA-ECMO. The main causes of immunosuppression were long-term corticosteroids/immunosuppressant treatment (29%), hematological malignancy (26%), solid organ transplant (20%), and solid tumor (13%). Overall 90-day and 1-year mortality were 70% (95% confidence interval (CI) 63-77%) and 75% (95% CI 65-79%), respectively. Older age and higher pre-ECMO lactate were independently associated with 90-day mortality. Across immunodepression causes, 1-year mortality ranged from 58% for patients with infection by human immunodeficiency virus (HIV) or asplenia, to 89% for solid organ transplant recipients. Hemorrhagic and infectious complications affected 39% and 54% of patients, while more than half the stay in intensive care unit (ICU) was spent on antibiotics. In a propensity score-weighted model comparing the 177 patients with 942 non-immunocompromised patients experiencing cardiogenic shock on VA-ECMO, immunocompromised status was independently associated with a higher 90-day mortality (odds ratio 2.53, 95% CI 1.72-3.79). CONCLUSION: Immunocompromised patients undergoing VA-ECMO treatment face an unfavorable prognosis, with higher 90-day mortality compared to non-immunocompromised patients. This underscores the necessity for thorough evaluation and careful selection of ECMO candidates within this frail population.

Increasing sweep gas flow reduces respiratory drive and dyspnea in non-intubated veno-arterial ECMO patients - a pilot study.

BACKGROUND.: Data on assessment and management of dyspnea in patients on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock are lacking. We hypothesized that increasing sweep gas flow through the VA-ECMO oxygenator may decrease dyspnea in non-intubated VA-ECMO patients exhibiting clinically significant dyspnea, with a parallel reduction in respiratory drive. METHODS.: Non-intubated, spontaneously breathing, supine patients on VA-ECMO for cardiogenic shock who presented with a visual analog dyspnea scale (dyspnea-VAS) ≥ 40/100 mm were included. Sweep gas flow was increased up to +6 L/min by three steps of +2 L/min each. Dyspnea was assessed with dyspnea-VAS and Multidimensional Dyspnea Profile. The respiratory drive was assessed by the electromyographic activity of the alae nasi and parasternal muscles. RESULTS.: We included 21 patients. On inclusion, median dyspnea-VAS was 50 ([interquartile range] 45-60) mm and sweep gas flow was 1.0 L/min (0.5-2.0). An increase in sweep gas flow significantly decreased dyspnea-VAS (50[45-60] at baseline vs 20[10-30] at 6L/min; p<0.001). The decrease in dyspnea was greater for the sensory component of dyspnea (-50%[43-75]) than for the affective and emotional components (-17%[0-25] and -12%[0-17], p<0.001). An increase in sweep gas flow significantly decreased electromyographic activity of the alae nasi and parasternal muscles (-23%[36-10] and -20[41-0], p<0.001). There was a significant correlation between the sweep gas flow and the dyspnea-VAS (r=-0.91 95%CI[-0.94, -0.87]), between the respiratory drive and the sensory component of dyspnea (r=0.29 95%CI[0.13, 0.44]), between the respiratory drive and the affective component of dyspnea (r=0.29 95%CI[0.02, 0.54]) and between the sweep gas flow and the alae nasi and parasternal (r=-0.31 95%CI[-0.44, -0.22] and r=-0.25 95%CI[-0.44, -0.16]). CONCLUSION.: In critically ill patients with VA-ECMO, an increase in sweep gas flow through the oxygenation membrane decreases dyspnea, possibly mediated by a decrease in respiratory drive.

Bleeding complications, coagulation disorders, and their management in acute myocardial infarction-related cardiogenic shock rescued by veno-arterial ECMO: A retrospective cohort study.

PURPOSE: Management of dual antiplatelet therapy (DAPT) in patients on venoarterial-extracorporeal membrane (VA-ECMO) after acute myocardial infarction (AMI) is challenging. Our objective was to describe the frequency, management and outcomes of severe bleeding complications and determine their occurrence risk factors. MATERIAL AND METHODS: We conducted a retrospective observational cohort study including post-AMI cardiogenic shock patients requiring VA-ECMO. Severe bleeding was defined based on the Bleeding Academic Research Consortium classification. We calculated multivariable Fine-Gray models to assess factors associated with risk of severe bleeding. RESULTS: From January 2015 to July 2019, 176 patients received VA-ECMO after AMI and 132 patients were included. Sixty-five (49%) patients died. Severe bleeding occurred in 39% of cases. Severe thrombocytopenia (< 50 G/L) and hypofibrinogenemia (<1,5 g/L) occurred in respectively 31% and 19% of patients. DAPT was stopped in 32% of patients with a 6% rate of stent thrombosis. Anticoagulation was stopped in 39% of patients. Using a multivariate competing risk model, female sex, time on ECMO, troponin at admission and Impella® implantation were independently associated with severe bleeding. CONCLUSIONS: Bleeding complications and coagulation disorders were frequent and severe in patients on VA-ECMO after AMI, leading of antiplatelet therapy withdrawal in one third of patients.

Ceftazidime/avibactam serum concentration in patients on ECMO.

OBJECTIVES: The use of extracorporeal membrane oxygenation (ECMO) may alter blood levels of several drugs, including antibiotics, leading to under dosing of these drugs and thus to potential treatment failure. No data exist on pharmacokinetics of new antimicrobial, in particular ceftazidime/avibactam. We therefore perform this study to evaluate ceftazidime/avibactam blood levels in ECMO patients and find factors associated with underdosing. METHODS: Retrospective observational study of patients on ECMO having received ceftazidime/avibactam and in whom trough blood levels of ceftazidime and avibactam were available. Main outcome measurement was the number of patients with ceftazidime and avibactam blood levels above predefined cut-off values, derived from the European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints for Enterobacteriaceae and Pseudomonas aeruginosa, namely 8 mg/L for ceftazidime and 4 mg/L for avibactam, and explored factors associated with underdosing. RESULTS: Twenty-three ceftazidime/avibactam trough levels were available in 14 ECMO patients, all of them having received veno-venous ECMO for SARS-CoV-2-associated pneumonia. Although ceftazidime levels were above 8 mg/L in all except one patient, nine (39%) of the avibactam dosages were below 4 mg/L. Increased renal clearance (creatinine clearance > 130 mL/min) was the main factor associated with under dosing, since 7 out of the 10 dosages below the predefined cut-offs were measured in patients with this condition. CONCLUSIONS: In ECMO patients receiving ceftazidime/avibactam, ceftazidime and avibactam serum levels are above EUCAST breakpoints in most cases, justifying the use of normal dosing in ECMO patients. Increased renal clearance may lead to ceftazidime and avibactam under dosing.

Healthcare-associated infections in patients with severe COVID-19 supported with extracorporeal membrane oxygenation: a nationwide cohort study.

BACKGROUND: Both critically ill patients with coronavirus disease 2019 (COVID-19) and patients receiving extracorporeal membrane oxygenation (ECMO) support exhibit a high incidence of healthcare-associated infections (HAI). However, data on incidence, microbiology, resistance patterns, and the impact of HAI on outcomes in patients receiving ECMO for severe COVID-19 remain limited. We aimed to report HAI incidence and microbiology in patients receiving ECMO for severe COVID-19 and to evaluate the impact of ECMO-associated infections (ECMO-AI) on in-hospital mortality. METHODS: For this study, we analyzed data from 701 patients included in the ECMOSARS registry which included COVID-19 patients supported by ECMO in France. RESULTS: Among 602 analyzed patients for whom HAI and hospital mortality data were available, 214 (36%) had ECMO-AI, resulting in an incidence rate of 27 ECMO-AI per 1000 ECMO days at risk. Of these, 154 patients had bloodstream infection (BSI) and 117 patients had ventilator-associated pneumonia (VAP). The responsible microorganisms were Enterobacteriaceae (34% for BSI and 48% for VAP), Enterococcus species (25% and 6%, respectively) and non-fermenting Gram-negative bacilli (13% and 20%, respectively). Fungal infections were also observed (10% for BSI and 3% for VAP), as were multidrug-resistant organisms (21% and 15%, respectively). Using a Cox multistate model, ECMO-AI were not found associated with hospital death (HR = 1.00 95% CI [0.79-1.26], p = 0.986). CONCLUSIONS: In a nationwide cohort of COVID-19 patients receiving ECMO support, we observed a high incidence of ECMO-AI. ECMO-AI were not found associated with hospital death. Trial registration number NCT04397588 (May 21, 2020).

High Airway Occlusion Pressure Is Associated with Dyspnea and Increased Mortality in Critically Ill Mechanically Ventilated Patients.

RATIONALE: 100 ms airway occlusion pressure (P0.1) reflects central respiratory drive. We aimed to assess factors associated with P0.1 and whether an abnormally low or high P0.1 value is associated with higher mortality and longer duration of mechanical ventilation (MV). METHODS: Secondary analysis of a prospective cohort study conducted in 10 intensive care units in France to evaluate dyspnea in communicative MV patients. In patients intubated for more than 24 hours, P0.1 was measured with dyspnea as soon as patients could communicate and the following day. RESULTS: 260 patients were assessed after a median time of ventilation of 4 days. P0.1 was 1.9 (1 - 3.5) cmH2O on enrollment, 24% had a P0.1 >3.5 cmH2O, 37% had a P0.1 between 1.5 and 3.5 cmH2O, and 39% had a P0.1 <1.5 cmH2O. In multivariable linear regression, independent factors associated with P0.1 level were presence of dyspnea (p=0.037), respiratory rate (p<0.001), and PaO2 (p=0.008). 90-day mortality was 33% in patients with P0.1 >3.5 cmH2O vs. 19% in those with a P0.1 between 1.5 and 3.5 cmH2O and 17% in patients with P0.1 <1.5 cmH2O (p=0.046). After adjustment for the main risk factors, P0.1 was associated with 90-day mortality (per cmH2O of P0.1, Hazard ratio 1.19, 95% Confidence interval 1.04 - 1.37, p=0.011). P0.1 was also independently associated with a longer duration of MV (per cmH2O of P0.1, Hazard ratio 1.10, 95% Confidence interval 1.02-1.19, p=0.016). CONCLUSIONS: In patients receiving invasive mechanical ventilation, abnormally high P0.1 values may suggest dyspnea and is associated with higher mortality and prolonged duration of MV.

Anticoagulation and Bleeding during Veno-Venous Extracorporeal Membrane Oxygenation: Insights from the PROTECMO Study.

Rationale: Definitive guidelines for anticoagulation management during veno-venous extracorporeal membrane oxygenation (VV ECMO) are lacking, whereas bleeding complications continue to pose major challenges. Objectives: To describe anticoagulation modalities and bleeding events in adults receiving VV ECMO. Methods: This was an international prospective observational study in 41 centers, from December 2018 to February 2021. Anticoagulation was recorded daily in terms of type, dosage, and monitoring strategy. Bleeding events were reported according to site, severity, and impact on mortality. Measurements and Main Results: The study cohort included 652 patients, and 8,471 days on ECMO were analyzed. Unfractionated heparin was the initial anticoagulant in 77% of patients, and the most frequently used anticoagulant during the ECMO course (6,221 d; 73%). Activated partial thromboplastin time (aPTT) was the most common test for monitoring coagulation (86% of days): the median value was 52 seconds (interquartile range, 39 to 61 s) but dropped by 5.3 seconds after the first bleeding event (95% confidence interval, -7.4 to -3.2; P < 0.01). Bleeding occurred on 1,202 days (16.5%). Overall, 342 patients (52.5%) experienced at least one bleeding event (one episode every 215 h on ECMO), of which 10 (1.6%) were fatal. In a multiple penalized Cox proportional hazard model, higher aPTT was a potentially modifiable risk factor for the first episode of bleeding (for 20-s increase; hazard ratio, 1.07). Conclusions: Anticoagulation during VV ECMO was a dynamic process, with frequent stopping in cases of bleeding and restart according to the clinical picture. Future studies might explore lower aPTT targets to reduce the risk of bleeding.

Electrical Impedance Tomography to Monitor Hypoxemic Respiratory Failure.

Hypoxemic respiratory failure is one of the leading causes of mortality in intensive care. Frequent assessment of individual physiological characteristics and delivery of personalized mechanical ventilation (MV) settings is a constant challenge for clinicians caring for these patients. Electrical impedance tomography (EIT) is a radiation-free bedside monitoring device that is able to assess regional lung ventilation and changes in aeration. With real-time tomographic functional images of the lungs obtained through a thoracic belt, clinicians can visualize and estimate the distribution of ventilation at different ventilation settings or following procedures such as prone positioning. Several studies have evaluated the performance of EIT to monitor the effects of different MV settings in patients with acute respiratory distress syndrome, allowing more personalized MV. For instance, EIT could help clinicians find the positive end-expiratory pressure that represents a compromise between recruitment and overdistension and assess the effect of prone positioning on ventilation distribution. The clinical impact of the personalization of MV remains to be explored. Despite inherent limitations such as limited spatial resolution, EIT also offers a unique noninvasive bedside assessment of regional ventilation changes in the ICU. This technology offers the possibility of a continuous, operator-free diagnosis and real-time detection of common problems during MV. This review provides an overview of the functioning of EIT, its main indices, and its performance in monitoring patients with acute respiratory failure. Future perspectives for use in intensive care are also addressed.

Survival and Long-Term Functional Status of COVID-19 Patients Requiring Prolonged Extracorporeal Membrane Oxygenation Support.

Rationale: Severe cases of acute respiratory distress syndrome (ARDS) may require prolonged (>28 d) extracorporeal membrane oxygenation (ECMO). In nonresolving disease, recovery is uncertain, and lung transplant may be proposed. Objectives: This study aims to identify the variables influencing survival and to describe the functional status of these patients at 6 months. Methods: This was a retrospective, multicenter, observational cohort study including patients requiring ECMO support for coronavirus disease (COVID-19)-related ARDS for >28 days. Multivariate analysis was performed using Cox regression in preselected variables and in least absolute shrinkage and selection operator selected variables. In a post hoc analysis to account for confounders and differences in awake strategy use by centers, treatment effects of the awake strategy were estimated using an augmented inverse probability weighting estimator with robust standard errors clustered by center. Results: Between March 15, 2020 and March 15, 2021, 120 patients required ECMO for >28 days. Sixty-four patients (53.3%) survived decannulation, 62 (51.7%) were alive at hospital discharge, and 61 (50.8%) were alive at 6-month follow-up. In the multivariate analysis, age (1.09; 95% confidence interval [CI], 1.03-1.15; P = 0.002) and an awake ECMO strategy (defined as the patient being awake, cooperative, and performing rehabilitation and physiotherapy with or without invasive mechanical ventilation at any time during the extracorporeal support) (0.14; 95% CI, 0.03-0.47; P = 0.003) were found to be predictors of hospital survival. At 6 months, 51 (42.5%) patients were at home, 42 (84.3%) of them without oxygen therapy. A cutoff point of 47 ECMO days had a 100% (95% CI, 76.8-100%) sensitivity and 60% (95% CI, 44.3-73.6%) specificity for oxygen therapy at 6 months, with 100% specificity being found in 97 days. Conclusions: Patients with COVID-19 who require ECMO for >28 days can survive with nonlimiting lung impairment. Age and an awake ECMO strategy may be associated with survival. Longer duration of support correlates with need for oxygen therapy at 6 months.

Prone Positioning During Extracorporeal Membrane Oxygenation in Patients With Severe ARDS: The PRONECMO Randomized Clinical Trial.

Importance: Prone positioning may improve outcomes in patients with severe acute respiratory distress syndrome (ARDS), but it is unknown whether prone positioning improves clinical outcomes among patients with ARDS who are undergoing venovenous extracorporeal membrane oxygenation (VV-ECMO) compared with supine positioning. Objective: To test whether prone positioning vs supine positioning decreases the time to successful ECMO weaning in patients with severe ARDS supported by VV-ECMO. Design, Setting, and Participants: Randomized clinical trial of patients with severe ARDS undergoing VV-ECMO for less than 48 hours at 14 intensive care units (ICUs) in France between March 3, 2021, and December 7, 2021. Interventions: Patients were randomized 1:1 to prone positioning (at least 4 sessions of 16 hours) (n = 86) or to supine positioning (n = 84). Main Outcomes and Measures: The primary outcome was time to successful ECMO weaning within 60 days following randomization. Secondary outcomes included ECMO and mechanical ventilation-free days, ICU and hospital length of stay, skin pressure injury, serious adverse events, and all-cause mortality at 90-day follow-up. Results: Among 170 randomized patients (median age, 51 [IQR, 43-59] years; n = 60 women [35%]), median respiratory system compliance was 15.0 (IQR, 10.7-20.6) mL/cm H2O; 159 patients (94%) had COVID-19-related ARDS; and 164 (96%) were in prone position before ECMO initiation. Within 60 days of enrollment, 38 of 86 patients (44%) had successful ECMO weaning in the prone ECMO group compared with 37 of 84 (44%) in the supine ECMO group (risk difference, 0.1% [95% CI, -14.9% to 15.2%]; subdistribution hazard ratio, 1.11 [95% CI, 0.71-1.75]; P = .64). Within 90 days, no significant difference was observed in ECMO duration (28 vs 32 days; difference, -4.9 [95% CI, -11.2 to 1.5] days; P = .13), ICU length of stay, or 90-day mortality (51% vs 48%; risk difference, 2.4% [95% CI, -13.9% to 18.6%]; P = .62). No serious adverse events were reported during the prone position procedure. Conclusions and Relevance: Among patients with severe ARDS supported by VV-ECMO, prone positioning compared with supine positioning did not significantly reduce time to successful weaning of ECMO. Trial Registration: ClinicalTrials.gov Identifier: NCT04607551.