Effect of Exogenous Albumin on the Incidence of Postoperative Acute Kidney Injury in Patients Undergoing Off-pump Coronary Artery Bypass Surgery with a Preoperative Albumin Level of Less Than 4.0 g/dl

Abstract

Background Hypoalbuminemia may increase the risk of acute kidney injury (AKI). The authors investigated whether the immediate preoperative administration of 20% albumin solution affects the incidence of AKI after off-pump coronary artery bypass surgery. Methods In this prospective, single-center, randomized, parallel-arm double-blind trial, 220 patients with preoperative serum albumin levels less than 4.0 g/dl were administered 100, 200, or 300 ml of 20% human albumin according to the preoperative serum albumin level (3.5 to 3.9, 3.0 to 3.4, or less than 3.0 g/dl, respectively) or with an equal volume of saline before surgery. The primary outcome measure was AKI incidence after surgery. Postoperative AKI was defined by maximal AKI Network criteria based on creatinine changes. Results Patient characteristics and perioperative data except urine output during surgery were similar between the two groups studied, the albumin group and the control group. Urine output (median [interquartile range]) during surgery was higher in the albumin group (550 ml [315 to 980]) than in the control group (370 ml [230 to 670]; P = 0.006). The incidence of postoperative AKI in the albumin group was lower than that in the control group (14 [13.7%] vs. 26 [25.7%]; P = 0.048). There were no significant between-group differences in severe AKI, including renal replacement therapy, 30-day mortality, and other clinical outcomes. There were no significant adverse events. Conclusion Administration of 20% exogenous albumin immediately before surgery increases urine output during surgery and reduces the risk of AKI after off-pump coronary artery bypass surgery in patients with a preoperative serum albumin level of less than 4.0 g/dl.

Causal relationship between hypoalbuminemia and acute kidney injury

“…This corroborates an earlier retrospective analysis in 1182 consecutive adult patients undergoing OPCAB, conducted by the same group[14]. Moreover, the data from Lee et al[13] further underline the importance of the relationship between albumin level and renal health, as correction of hypoalbuminemia by exogenous albumin supplementation resulted in smaller increases in serum creatinine and conferred a degree of protection against AKI occurrence. That no significant treatment effect on severe AKI was observed (≥ KDIGO stage 2) might reflect an underpowered analysis due to the relatively low sample size/event rate.…”

“…Whereas in the RCT performed by Lee et al[13] no differences were evident between the albumin and saline treatment groups with respect to subsequent need for RRT or mortality, precedent does exist for the impact of albumin level on both of these outcomes. Findik et al[15] recently performed a retrospective review of data collected prospectively from 530 adults with normal renal function who underwent isolated CAB surgery.…”

“…In the only interventional drug study among the 43 retained articles, Lee et al[13] recently performed a single-center, randomized, parallel-arm, double-blind trial which evaluated the effects of exogenous 20% human albumin solution vs saline on the incidence of postoperative AKI in adult patients with hypoalbuminemia (< 4.0 g/dL) undergoing off-pump coronary artery bypass (OPCAB) surgery. Dose was 100, 200, or 300 mL immediately before surgery, stratified according to preoperative serum albumin level of 3.5-3.9, 3.0-3.4, or < 3.0 g/dL, respectively.…”

“…Lee et al[13] did not investigate the mechanism(s) underlying the renal-protective effect they observed with albumin administration but speculated whether this might be attributable to augmentation of intravascular volume over correction of hypoalbuminemia. Indeed, both hemodynamic and pharmacodynamic mechanisms may contribute to the beneficial renal effects of albumin, supporting a possible causal link.…”

Prevention of acute kidney injury and protection of renal function in the intensive care unit: update 2017

“…A post hoc analysis of the ALBIOS trial showed survival benefit in septic shock [74] confirmed by meta-analyses [76, 77]. Hypoalbuminaemia in cardiac surgery might be another indication with improved fluid balance as well as a reduced rate of AKI being observed in a single-centre RCT of 220 patients [78]. …”