title: Timing of initiation of dialysis in critically ill patients with acute kidney injury.
abstract: Among critically ill patients, acute kidney injury (AKI) is a relatively common complication that is associated with an increased risk for death and other complications. To date, no treatment has been developed to prevent or attenuate established AKI. Dialysis often is required, but the optimal timing of initiation of dialysis is unknown. Data from the Program to Improve Care in Acute Renal Disease (PICARD), a multicenter observational study of AKI, were analyzed. Among 243 patients who did not have chronic kidney disease and who required dialysis for severe AKI, we examined the risk for death within 60 d from the diagnosis of AKI by the blood urea nitrogen (BUN) concentration at the start of dialysis (BUN < or = 76 mg/dl in the low degree of azotemia group [n = 122] versus BUN > 76 mg/dl in the high degree of azotemia group [n = 121]). Standard Kaplan-Meier product limit estimates, proportional hazards (Cox) regression methods, and a propensity score approach were used to account for selection effects. Crude survival rates were slightly lower for patients who started dialysis at higher BUN concentrations, despite a lesser burden of organ system failure. Adjusted for age, hepatic failure, sepsis, thrombocytopenia, and serum creatinine and stratified by site and initial dialysis modality, the relative risk for death that was associated with initiation of dialysis at a higher BUN was 1.85 (95% confidence interval 1.16 to 2.96). Further adjustment for the propensity score did not materially alter the association (relative risk 1.97; 95% confidence interval 1.21 to 3.20). Among critically ill patients with AKI, initiation of dialysis at higher BUN concentrations was associated with an increased risk for death. Although the results could reflect residual confounding by severity of illness, they provide a rationale for prospective testing of alternative dialysis initiation strategies in critically ill patients with severe AKI.
authors: Division of Nephrology, Department of Medicine, University of California San Francisco, USA. chertowg@medicine.ucsf.edu
authors: Kathleen D
authors: KD
authors: Liu
authors: Jonathan
authors: J
authors: Himmelfarb
authors: Emil
authors: E
authors: Paganini
authors: T Alp
authors: TA
authors: Ikizler
authors: Sharon H
authors: SH
authors: Soroko
authors: Ravindra L
authors: RL
authors: Mehta
authors: Glenn M
authors: GM
authors: Chertow
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000150:complications / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy*; D053099:Azotemia / Q000097:blood / Q000209:etiology* / Q000401:mortality / Q000628:therapy; D015415:Biomarkers / Q000097:blood; D001806:Blood Urea Nitrogen; D016638:Critical Illness; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D016016:Proportional Hazards Models; D006435:Renal Dialysis; D018570:Risk Assessment; D012720:Severity of Illness Index; D013997:Time Factors; D014481:United States / Q000453:epidemiology
chemical_list: D015415:Biomarkers