Direct Connection to the ECMO Circuit versus a Hemodialysis Catheter Is Associated with Improved Urea Nitrogen Ultrafiltration during Continuous Renal Replacement Therapy for Patients on Extracorporeal Membrane Oxygenation

J Clin Med. 2023 Feb 13;12(4):1488. doi: 10.3390/jcm12041488.

Abstract

For patients on extracorporeal membrane oxygenation (ECMO) who require renal replacement therapy (RRT), dialysis can be achieved through a dedicated hemodialysis (HD) catheter or direct connection to the ECMO circuit. The relative effect of each on filtration efficacy is not known. We conducted a retrospective single-center analysis of patients on ECMO who required CRRT. We examined the outcomes of blood biomarkers and transmembrane filter pressures, comparing sessions by attachment approach. All analyses were clustered by patient. Of the 33 patients (7 ECMO access and 23 HD catheter access) that met the inclusion criteria, there were a total of 493 CRRT sessions (93 ECMO access and 400 HD catheter access). At the end of the first 12 h of CRRT therapy, the ECMO group had a greater rate of decline in serum BUN than the HD catheter access group (2.5 mg/dl (SD 11) vs. 2 mg/dl (SD 6), p = 0.035). Additionally, the platelet level was significantly higher in the ECMO group compared to the HD catheter access group after 72 h (94.5 k/uL (SD 41) vs. 71 k/uL (SD 29), p = 0.008). Utilizing the ECMO circuit as direct venous access for CRRT was associated with some improved filtration proximal outcomes.

Keywords: CRRT; HD; dialysis; renal failure; ultrafiltration.