Cost-effectiveness of Chloride-liberal versus Chloriderestrictive Intravenous Fluids among Patients Hospitalized in the United States

Abstract

Background: Patients developing acute kidney injury (AKI) during critical illness or major surgery are at risk for renal sequelae such as costly and invasive acute renal replacement therapy (RRT) and chronic dialysis (CD). Rates of renal injury may be reduced with use of chloride-restrictive intravenous (IV) resuscitation fluids instead of chloride-liberal fluids. Objectives: To compare the cost-effectiveness of chloride-restrictive versus chloride-liberal crystalloid fluids used during fluid resuscitation or for the maintenance of hydration among patients hospitalized in the US for critical illnesses or major surgery. Methods: Clinical outcomes and costs for a simulated patient cohort (starting age 60 years) receiving either chloride-restrictive or chloride-liberal crystalloids were estimated using a decision tree for the first 90-day period after IV fluid initiation followed by a Markov model over the remainder of the cohort lifespan. Outcomes modeled in the decision tree were AKI development, recovery from AKI, progression to acute RRT, progression to CD, and death. Health states included in the Markov model were dialysis free without prior AKI, dialysis-free following AKI, CD, and death. Estimates of clinical parameters were taken from a recent meta-analysis, other published studies, and the US Renal Data System. Direct healthcare costs (in 2015 USD) were included for IV fluids, RRT, and CD. US-normalized health-state utilities were used to calculate quality-adjusted life years (QALYs). Results: In the cohort of 100 patients, AKI was predicted to develop in the first 90 days in 36 patients receiving chloride-liberal crystalloids versus 22 receiving chloride-restrictive crystalloids. Higher costs of chloride-restrictive crystalloids were offset by savings from avoided renal adverse events. Chloride-liberal crystalloids were dominant over chloride-restrictive crystalloids, gaining 93.5 life-years and 81.4 QALYs while saving $298 576 over the cohort lifespan. One-way sensitivity analyses indicated results were most sensitive to the relative risk for AKI development and relatively insensitive to fluid cost. In probabilistic sensitivity analyses with 1000 iterations, chloride-restrictive crystalloids were dominant in 94.7% of iterations, with incremental cost-effectiveness ratios below $50 000/QALY in 99.6%. Conclusions: This analysis predicts improved patient survival and fewer renal complications with chloriderestrictive IV fluids, yielding net savings versus chloride-liberal fluids. Results require confirmation in adequately powered head-to-head randomized trials.