Dextran‐based priming solution during cardiopulmonary bypass attenuates renal tubular injury—A secondary analysis of randomized controlled trial in adult cardiac surgery patients

Abstract

Background Acute kidney injury (AKI) is a well‐known complication after cardiac surgery and cardiopulmonary bypass (CPB). In the present secondary analysis of a blinded randomized controlled trial, we evaluated the effects of a colloid‐based versus a conventional crystalloid‐based prime on tubular injury and postoperative renal function in patients undergoing cardiac surgery with CPB. Methods Eighty‐four adult patients undergoing cardiac surgery with CPB were randomized to receive either a crystalloid‐ or colloid‐ (dextran 40) based CPB priming solution. The crystalloid solution was based on Ringer‐Acetate plus mannitol. The tubular injury biomarker, N‐acetyl‐b‐D‐glucosaminidase (NAG), serum creatinine and diuresis were measured before, during and after CPB. The incidence of AKI was assessed according to the KDIGO criteria. Results The urinary‐NAG/urinary‐creatinine ratio rose in both groups during and after CPB, with a more pronounced increase in the crystalloid group (p = .038). One hour after CPB, the urinary‐NAG/urinary‐creatinine ratio was 88% higher in the crystalloid group (4.7 ± 6.3 vs. 2.5 ± 2.7, p = .045). Patients that received the dextran 40‐based priming solution had a significantly lower intraoperative diuresis (p < .001) compared to the crystalloid group. The incidence of AKI was 18% in the colloid and 22% in the crystalloid group (p = .66). Postoperative serum creatinine did not differ between groups. Conclusions In patients undergoing cardiac surgery with CPB, colloid‐based priming solution (dextran 40) induced less renal tubular injury compared to a crystalloid‐based priming solution. Whether a colloid‐based priming solution will improve renal outcome in high‐risk cardiac surgery, or not, needs to be evaluated in future studies on higher risk cardiac surgery patients.

Adverse renal effects associated with cardiopulmonary bypass

“…98 Another small (n = 84) RCT has examined a dextran-based priming fluid, in comparison with a crystalloid and mannitol solution, finding a reduction in a marker of renal tubular injury (N-acetyl-b-Dglucosaminidase (NAG)), but not in the incidence of AKI (18% vs 22%, p = 0.66). 99 European guidance acknowledges the lack of consensus in optimal priming solution, although recommends against the use of starch solutions. 89 In the absence of conclusive evidence, the use of balanced crystalloids with supplemental exogenous colloid, and RAP appears appropriate for renal outcomes.…”

“… 98 Another small ( n = 84) RCT has examined a dextran-based priming fluid, in comparison with a crystalloid and mannitol solution, finding a reduction in a marker of renal tubular injury (N-acetyl-b-D-glucosaminidase (NAG)), but not in the incidence of AKI (18% vs 22%, p = 0.66). 99 …”

Management of priming fluids in cardiopulmonary bypass for adult cardiac surgery: network meta-analysis

“…Nine studies [ 22 , 25 , 26 , 30 , 35 , 36 , 38 , 40 , 41 ] included data on mortality. Based on the eight priming fluids, Figure 2(B) demonstrates a qualified network diagram of mortality for balanced crystalloids, 0.9% NaCl, iso-oncotic HA, hyperoncotic HA, L-HES, H-HES, gelatin, and dextran.…”

“…Three studies [ 25 , 34 , 37 ] included data on urine output 24h after surgery. Based on the four priming fluids, Figure 2(D) provides a qualified network diagram for urine output 24h after surgery for balanced crystalloids, L-HES, H-HES, and dextran.…”

“…Ten studies [ 22 , 23 , 25 , 31 , 32 , 35 , 38 , 40–42 ] included data on length of ICU stay. Based on the eight priming fluids, Figure 2(E) exhibits the qualified network diagram of the length of ICU stay for balanced crystalloids, 0.9% NaCl, iso-oncotic HA, hyperoncotic HA, L-HES, H-HES, gelatin, and dextran.…”