Early versus delayed initiation of renal replacement therapy in cardiac-surgery associated acute kidney injury: an economic perspective

Background: Timing for renal replacement therapy (RRT) initiation for cardiac-surgery associated acute kidney surgery (CSA-AKI) is subject to debate. Evidence suggests earlier initiation leads to shorter length of stay (LoS). We investigated differences in healthcare costs associated with timing of RRT initiation in CSA-AKI.

Methods: A cost-consequences model compared costs of Early (<24 h) vs. Delayed (>24 h) RRT initiation. Data were from the ELAIN trial in Germany, and the HiDenIC database, a US multi-hospital database. Resource utilization was determined by RRT duration, ICU, and hospital LoS. All resources were costed from a US healthcare perspective. Extensive sensitivity analyses (SA) were conducted, notably regarding the proportion of patients not initiated on RRT with the Delayed strategy.

Results: Early RRT initiation exhibited cost savings compared to Delayed RRT initiation. With ELAIN data, savings reached -$122,188 (ranging from -$157,707 to -$74,763 in the SA). Findings were confirmed with HiDenIC data; Early RRT initiation showed savings of -$77,303 (ranging from -$108,971 to -$47,012 in the SA).

Conclusions: Our costing model indicates that Early RRT initiation for CSA-AKI may result in appreciable cost savings. Delaying RRT, in the setting of CSA-AKI, may lead to longer LoS and increased healthcare costs.