Impact of timing of renal replacement therapy initiation on outcome of septic acute kidney injury

Abstract

IntroductionSepsis is the leading cause of acute kidney injury (AKI) in critical patients. The optimal timing of initiating renal replacement therapy (RRT) in septic AKI patients remains controversial. The objective of this study is to determine the impact of early or late initiation of RRT, as defined using the simplified RIFLE (risk, injury, failure, loss of kidney function, and end-stage renal failure) classification (sRIFLE), on hospital mortality among septic AKI patients.MethodsPatient with sepsis and AKI requiring RRT in surgical intensive care units were enrolled between January 2002 and October 2009. The patients were divided into early (sRIFLE-0 or -Risk) or late (sRIFLE-Injury or -Failure) initiation of RRT by sRIFLE criteria. Cox proportional hazard ratios for in hospital mortality were determined to assess the impact of timing of RRT.ResultsAmong the 370 patients, 192 (51.9%) underwent early RRT and 259 (70.0%) died during hospitalization. The mortality rate in early and late RRT groups were 70.8% and 69.7% respectively (P > 0.05). Early dialysis did not relate to hospital mortality by Cox proportional hazard model (P > 0.05). Patients with heart failure, male gender, higher admission creatinine, and operation were more likely to be in the late RRT group. Cox proportional hazard model, after adjustment with propensity score including all patients based on the probability of late RRT, showed early dialysis was not related to hospital mortality. Further model matched patients by 1:1 fashion according to each patient's propensity to late RRT showed no differences in hospital mortality according to head-to-head comparison of demographic data (P > 0.05).ConclusionsUse of sRIFLE classification as a marker poorly predicted the benefits of early or late RRT in the context of septic AKI. In the future, more physiologically meaningful markers with which to determine the optimal timing of RRT initiation should be identified.

Dialysis versus Nondialysis in Patients with AKI

“…Without this, no conclusion regarding the effectiveness of dialysis versus nondialysis can be made. In general, studies examining patients dialyzed at a high creatinine versus those dialyzed at a low creatinine have demonstrated that outcomes are better when dialysis is initiated at a higher creatinine concentration (20,(22)(23)(24)(25). Our results confirm and expand upon those seen in prior studies.…”

“…Prior studies examining the initiation of dialysis for AKI have not generated consensus (13)(14)(15)(16)(17)(18)(19)(20)(21)(22). Significantly heterogenous, these studies fail to include an adequate nondialyzed control group.…”

Classical Indications Are Useful for Initiating Continuous Renal Replacement Therapy in Critically Ill Patients

“…Shiao et al (2009) reported that the RIFLE criteria were useful in predicting post-AKI mortality; however, Chou et al (2011) stated that the RIFLE criteria were not associated with the mortality of critically ill patients with AKI. In our study, we noted that the AKIN stage (stage 2: HR, 0.819; 95% CI, 0.527-1.273; stage 3: HR, 1.277; 95% CI, 0.945-1.725; reference, stage 0 or 1) was not associated with the risk of mortality after AKI.…”

Timing of Initiation of Renal Replacement Therapy in Acute Kidney Injury: A Systematic Review and Meta-analysis

“…Manche [17] 2008 IHD Cardiac surgery Hyperkalemia Urine output <0.5mL/kg/h Iyem [18] 2009 CVVH Cardiac surgery RRT on admission After 48 h when anuric Shiao [19] 2009 CVVH Surgery/trauma RIFLE criteria (risk) RIFLE injury (failure) Carl [20] 2010 CRRT/IHD Medical (sepsis) Urea <35.7 mmol/L Urea >35.7 mmol/L Chou [21] 2011 CRRT/SLED Sepsis RIFLE criteria (risk) RIFLE injury (failure) García-Fernández [22] 2011 CRRT/IHD Cardiac surgery ≤3 days after cardiac surgery >3 days after cardiac surgery Note: RIFLE Criteria (Risk): Increase in serum creatinine by 1.5 times or urine output <0.5 mL/kg/h × 6 h; RIFLE Criteria Injury: Increase in serum creatinine by 2 times or urine output <0.5 mL/kg/h × 12 h; RIFLE Criteria (Failure): Increase in serum creatinine by 3 times or urine output <0.3 mL/kg/h × 24 h. the definition of "early" and "late" RRTs. Patients in seven studies 2,3,[13][14][15]18,19 used CRRT and patients in two studies 10,17 used IHD.…”