Integration of sustained low‐efficiency dialysis into extracorporeal membrane oxygenation circuit in critically ill COVID‐19 patients—A feasibility study

BACKGROUND: Severe COVID‐19 can necessitate multiple organ support including veno‐venous extracorporeal membrane oxygenation (vvECMO) and renal replacement therapy. The therapy can be complicated by venous thromboembolism due to COVID‐19‐related hypercoagulability, thus restricting vascular access beyond the vvECMO cannula. Although continuous renal replacement therapy can be performed via a vvECMO circuit, studies addressing sustained low‐efficiency dialysis (SLED) integration into vvECMO circuits are scarce. Here we address the lack of evidence by evaluating feasibility of SLED integration into vvECMO circuits. METHODS: Retrospective cohort study on nine critically ill COVID‐19 patients, treated with integrated ECMO‐SLED on a single intensive care unit at a tertiary healthcare facility between December 2020 and November 2021. The SLED circuits were established between the accessory arterial oxygenator outlets of a double‐oxygenator vvECMO setup. Data on filter survival, quality of dialysis, and volume management were collected and compared with an internal control group receiving single SLED. RESULTS: This study demonstrates general feasibility of SLED integration into existing vvECMO circuits. Filter lifespans of ECMO‐SLED compared with single SLED are significantly prolonged (median 18.3 h vs. 10.3 h, p < 0.01). ECMO‐SLED treatment is furthermore able to sufficiently normalize creatinine, blood urea nitrogen, and serum sodium, and allows for adequate ultrafiltration rates. CONCLUSIONS: We can show that ECMO‐SLED is practical, safe, results in adequate dialysis quality and enables sufficient electrolyte and volume management. Our data indicate that SLED devices can serve as potential alternative to continuous‐veno‐venous‐hemodialysis for integration in vvECMO circuits.