Fluid management in adult patients undergoing venoarterial extracorporeal membrane oxygenation: A scoping review

Background: The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) as a cardiocirculatory support has tremendously increased in critically ill patients. Although fluid therapy is an essential component of the hemodynamic management of VA-ECMO patients, the optimal fluid resuscitation strategy remains controversial. We performed a scoping review to map out the existing knowledge on fluid management in terms of fluid type, dosing and the impact of fluid balance on VA-ECMO patient outcomes. Methods: A literature search within PubMed and EMBASE was conducted from database inception to April 2024. We included all studies involving critically ill adult patients, supported by VA-ECMO regardless of clinical indication (cardiogenic shock or extracorporeal cardiopulmonary resuscitation) with or without Renal Replacement Therapy and describing fluid resuscitation strategies or focusing on fluid type or reporting the impact of fluid balance on clinical outcomes and mortality. Details of study population, ECMO indications, fluid types, resuscitation strategies, fluid balance and outcome measures were extracted. Results: Sixteen studies met inclusion criteria, including 14 clinical studies and two experimental animal studies. We found a lack of studies comparing restrictive and liberal approaches. No study has compared the efficacy and safety of balanced and saline solutions. The place of albumin, as an alternative fluid, should be investigated. Despite their heterogeneity, studies found a negative impact of both early and cumulative fluid overload on survival and renal outcomes. Conclusions: The available literature on the fluid management in VA-ECMO setting is scarce. More high-quality evidence is needed regarding optimal fluid dosing, type and resuscitation endpoints in order to standardize practice and improve outcomes.