Objective: Prophylactic hemofiltration has been reported, in one study, to reduce renal complications and death but necessitates additional up-front health care resource deployment in a critical care setting. We sought to explore the potential scope and cost-effectiveness of this strategy.
Design: Economic evaluation using decision analysis.
Setting: Tertiary or quaternary care hospital.
Patients: Subjects undergoing angiography at risk for developing contrast nephropathy.
Intervention: Prophylactic hemofiltration was compared with intravenous saline. Secondary models incorporated sodium bicarbonate and N-acetylcysteine as comparators.
Measurement and main results: The cost per quality-adjusted life year (QALY) gained with hemofiltration compared with intravenous saline in high-risk subjects (mean serum creatinine, 265 micromol/L) was 3,900 US dollars. This finding was sensitive to variations in several important variables. For instance, the cost-effectiveness ratio became less attractive (i.e., >50,000 US dollars/QALY) when hemofiltration was used in lower-risk subjects (serum creatinine, <265 micromol/L). The cost-effectiveness remained <50,000 US dollars/QALY provided that the relative risk of hemofiltration compared with saline alone was below 0.65 (reported relative risk, 0.10). Although based on indirect comparison of clinical efficacy, when N-acetylcysteine or sodium bicarbonate was used as the comparator, the cost per QALY gained for hemofiltration became markedly less attractive (50,100 US dollars and >1,000,000 US dollars), although the relative effectiveness of these three strategies strongly influenced the results.
Conclusions: Use of prophylactic hemofiltration in patients at high risk for contrast nephropathy may be potentially cost-effective only if certain conditions are satisfied, and its attractiveness is materially diminished when compared to other strategies. As this invasive therapy would entail certain immediate resource outlay, before considering its implementation it is crucial to confirm the clinical effectiveness and health care resource consequences of hemofiltration relative to current standards of care in future studies.