The impact of continuous renal replacement therapy on renal outcomes in dialysis-requiring acute kidney injury may be related to the baseline kidney function

Abstract

BackgroundMany controversies exist regarding the management of dialysis-requiring acute kidney injury (D-AKI). No clear evidence has shown that the choice of dialysis modality can change the survival rate or kidney function recovery of critically ill patients with D-AKI.MethodsWe conducted a retrospective study investigating patients (≥16 years old) admitted to an intensive care unit with D-AKI from 1999 to 2012. We analyzed D-AKI incidence, and outcomes, as well as the most commonly used dialysis modality over time. Outcomes were based on hospital mortality, renal function recovery (estimated glomerular filtration rate-eGFR), and the need for dialysis treatment at hospital discharge.ResultsIn 1,493 patients with D-AKI, sepsis was the main cause of kidney injury (56.2%). The comparison between the three study periods, (1999–2003, 2004–2008, and 2009–2012) showed an increased in incidence of D-AKI (from 2.56 to 5.17%; p = 0.001), in the APACHE II score (from 20 to 26; p < 0.001), and in the use of continuous renal replacement therapy (CRRT) as initial dialysis modality choice (from 64.2 to 72.2%; p < 0.001). The mortality rate (53.9%) and dialysis dependence at hospital discharge (12.3%) remained unchanged over time. Individuals who recovered renal function (33.8%) showed that those who had initially undergone CRRT had a higher eGFR than those in the intermittent hemodialysis group (54.0 × 46.0 ml/min/1.73 m2, respectively; p = 0.014). In multivariate analysis, type of patient, sepsis-associated AKI and APACHE II score were associated to death. For each additional unit of the APACHE II score, the odds of death increased by 52%. The odds ratio of death for medical patients with sepsis-associated AKI was estimated to be 2.93 (1.81–4.75; p < 0.001).ConclusionOur study showed that the incidence of D-AKI increased with illness severity, and the use of CRRT also increased over time. The improvement in renal outcomes observed in the CRRT group may be related to the better baseline kidney function, especially in the dialysis dependence patients at hospital discharge.Electronic supplementary materialThe online version of this article (doi:10.1186/s12882-017-0564-z) contains supplementary material, which is available to authorized users.

Effect of renal replacement therapy modalities on renal recovery and mortality for acute kidney injury: A PRISMA‐compliant systematic review and meta‐analysis

“…Results regarding to comparison in renal recovery, in‐hospital mortality, and in‐ICU mortality between AKI patients given CRRT and those given SLED were corresponding to previous studies 4,30 published in recent years. According to previous studies, worse baseline renal function and more frequent intradialytic hypotension were associated with lower likelihood of renal recovery 31,32 . Presence of stage III AKI, oliguria, and hemodynamic instability needing vasopressor are associated with increased mortality 33 .…”

“…According to previous studies, worse baseline renal function and more frequent intradialytic hypotension were associated with lower likelihood of renal recovery. 31,32 Presence of stage III AKI, oliguria, and hemodynamic instability needing vasopressor are associated with increased mortality. 33 Increased median bicarbonate, presence of hypertension, and high admission creatinine were various factors associated with decreased inpatient mortality.…”

Sustained low efficiency dialysis is non-inferior to continuous renal replacement therapy in critically ill patients with acute kidney injury

“…[ 30 , 32 , 34 – 36 ] However, eGFR at hospital discharge may overestimate renal function of subjects undergoing RRT due to their accompanying loss of muscle mass that occurs during conditions of serious illness. [ 37 , 38 ]…”

“…[32,[36][37][38] In a recent study, individuals who received SLED had a higher rate of dialysis dependence following hospital discharge than those who were first given CRRT. [37] However, it was observed that the subjects in the SLED group had a lower baseline eGFR compared with those in the CRRT group. [34] In our meta-analysis, we found that there were no significant differences in the rates of dialysis dependence and renal recovery posttreatment among patients treated with SLED compared with CRRT.…”

Comparison of Approaches for Prediction of Renal Replacement Therapy-Free Survival in Patients with Acute Kidney Injury

“…While there is not a widely accepted tool for prediction of adverse events in patients initiated on CRRT, the utility of such predictive approaches is extensive. Moreover, given that 25% of patients initiated on CRRT remain dialysis dependent on hospital discharge, identification of those who are likely to need chronic dialysis may aid patients and families in their care decisions [5, 6].…”