Focus on veno-venous ECMO in adults with severe ARDS

Abstract

Veno-venous extracorporeal membrane oxygenation (vvECMO) improves oxygenation and promotes carbon dioxide (CO 2 ) removal [1,2]. In the most severe form of ARDS, ECMO rapidly facilitates the correction of severe derangement in gas exchange and saves time, which allows one to treat the cause of lung injury. Recent advances in ECMO technology have improved safety and promoted its use [3][4][5].Knowledge of the gas exchange performance of membrane oxygenators is important to help choose the optimal system for patients suffering from acute respiratory failure. In an in vivo study of 317 vvECMO patients supported with four different ECMO systems, Lehle et al. [6] showed that CO 2 transfer was dependent on sweep gas flow and blood flow, while O 2 transfer was only dependent on blood flow when it was above 3 L/min.The association between ECMO use and the development of thrombocytopenia secondary to circuit-induced platelet activation and aggregation has been suggested, although never carefully evaluated. In a retrospective cohort study of 100 adults who received vvECMO for acute respiratory failure, Abrams et al. [7] demonstrated that the severity of critical illness and platelet count at the time of cannulation were independently associated with the development of severe thrombocytopenia, while the duration of ECMO support was not.A position paper [8] from an international group of experts described the optimal approach to organizing programs and delivering safe and proficient ECMO for acute respiratory failure. They encouraged restraint in the widespread use of ECMO until a better appreciation of both the potential clinical applications and the optimal techniques for performing ECMO are available. They also underlined the need for further randomized controlled trials assessing this technique.Using hospital ECMO volumes from 290 international centers, a retrospective study of more than 55,000 ECMO patients [9] found an association between higher adult ECMO hospital volume and lower ECMO mortality rates. Patients receiving ECMO at hospitals with more than 30 adult annual ECMO cases had significantly lower odds of mortality (adjusted odds ratio, 0.61; 95 % confidence interval 0.46-0.80) compared with those receiving ECMO at hospitals with fewer than six cases annually.In a review paper, Levy et al.[10] proposed a multistep therapeutic approach with optimization of ECMO blood flow, red blood cell transfusion, moderate hypothermia, and short-action beta-blockers for the management of persistent severe hypoxemia under vvECMO. Important technical considerations for the care of ECMO patients by nurses [11] and physicians were also detailed in a review.The optimal ventilatory strategy for ARDS patients under ECMO remains unclear. Controlled mechanical ventilation is recommended in the first few days [12]. While the ventilator settings should be as low as possible to reduce ventilator-induced lung injury (VILI), there is an increased risk of derecruitment. In a recent international study [13] it was suggested that higher PEEP ...

Anticoagulation Monitoring Under ECMO Support: A Comparative Study Between the Activated Coagulation Time and the Anti-Xa Activity Assay

“…Extracorporeal circulation (ECC), initially developed to allow few hours long cardiac surgery interventions, 1 has been used for decades as a respiratory and/or circulatory support in case of severe acute respiratory distress syndrome (ARDS), 2,3 cardiogenic shock, or refractory cardiac arrest 4 over periods of several days to several weeks, thanks to Extra Corporeal Membrane Oxygenation (ECMO) support. The ECMO circuitry requires an anticoagulation therapy that must be closely and frequently monitored due to a high risk of hemorrhagic and thrombotic complications.…”

Development of the First Adult Respiratory Extracorporeal Membrane Oxygenation Center in Croatia under Emergency Circumstances

“…A dramatic expansion of ECMO use over the last decade has led to the increased number of respiratory ECMO centers as well (9). Experts argue that such an uncontrolled increase in ECMO use will inevitably compromise the outcomes of patients treated with ECMO due to inexperience with the method, thus leading to the erroneous conclusion that the method itself is ineffective (10). Unfortunately, such suboptimal performance due to inexperience has been reported (11).…”

Challenges in extracorporeal membrane oxygenation

“…This last segment is the application of ECMO principally, and this level of mortality is usually what we want reduce by ECMO support. 109 But despite the efforts and promising results, this reduction of mortality is not consistently reached, and the application of ECMO in COVID-19 has demonstrated that the main goal is to apply the support to patients that have a real chance of survival and to apply the support at the right time. 32,49,50 One possible approach is personalized medicine to underline the biological processes common among different subpopulations in the same wide-ranging clinical category or definition.…”