Volume control strategy and patient survival in sepsis-associated acute kidney injury receiving continuous renal replacement therapy: a randomized controlled trial with secondary analysis

Abstract

Optimal strategy for volume control and the clinical implication of achieved volume control are unknown in patients with sepsis-associated acute kidney injury (AKI) receiving continuous renal replacement therapy (CRRT). This randomized controlled trial aimed to compare the survival according to conventional or bioelectrical impedance analysis (BIA)-guided volume control strategy in patients with sepsis-associated AKI receiving CRRT. We also compared patient survival according to achieved volume accumulation rate ([cumulative fluid balance during 3 days × 100]/fluid overload measured by BIA at enrollment) as a post-hoc analysis. We randomly assigned patients to conventional volume control strategy (n = 39) or to BIA-guided volume control strategy (n = 34). There were no differences in 28-day mortality (HR, 1.19; 95% CI, 0.63-2.23) or 90-day mortality (HR, 0.99; 95% CI 0.57-1.75) between conventional and BIA-guided volume control group. In the secondary analysis, achieved volume accumulation rate was significantly associated with patient survival. Compared with the achieved volume accumulation rate of ≤ - 50%, the HRs (95% CIs) for the risk of 90-day mortality were 1.21 (0.29-5.01), 0.55 (0.12-2.48), and 7.18 (1.58-32.51) in that of - 50-0%, 1-50%, and > 50%, respectively. Hence, BIA-guided volume control in patients with sepsis-associated AKI receiving CRRT did not improve patient outcomes. In the secondary analysis, achieved volume accumulation rate was associated with patient survival.

Keywords: Bioelectrical impedance analysis; Continuous renal replacement therapy; Sepsis-associated acute kidney injury; Volume control.

Figure 1

Kaplan–Meier curves showing patient survival according to volume control strategies. Cumulative survival probability within (A) 28-day and (B) 90-day of continuous renal replacement therapy initiation according to volume control strategies. Log-rank tests were used for comparison between groups. BIA bioelectrical impedance analysis.

Figure 2

Flow diagram of study participants. From June 2017 to October 2021, a total of 759 patients who initiated continuous renal replacement therapy at Severance Hospital (Seoul, Republic of Korea) were initially assessed for eligibility. According to inclusion and exclusion criteria, 73 patients were included in the primary analysis (intention-to-treat analysis). After excluding 18 patients who did not complete the 3 days of intervention, 55 subjects were included in the secondary analysis. BIA bioelectrical impedance analysis; CRRT continuous renal replacement therapy.