Comparison Between Ringer's Lactate Solution vs. Normal Saline with Dextrose Water in the Postoperative Period of Kidney Transplantation: A Randomized Controlled Trial

Background: Postoperative intravenous(IV) fluid management in kidney transplantation(KT) has shifted toward balanced crystalloids due to concerns that normal saline(NSS) may contribute to hyperchloremic metabolic acidosis and delayed graft function(DGF). Some centers use NSS with 5% dextrose water(D5W) to reduce chloride load. This study aimed to compared the efficacy of Ringer’s lactate solution(RLS) versus NSS+D5W in preventing metabolic acidosis in KT recipients(KTRs). Methods: This open-label, randomized controlled trial, conducted at King Chulalongkorn Memorial Hospital, enrolled adult KTRs from living or deceased donors. Patients were randomized to receive postoperative IV fluid as either RLS or NSS+D5W. The primary outcome was metabolic acidosis assessed by serum bicarbonate and pH at postoperative day4. Secondary outcomes included DGF, serum electrolytes, graft function at 1 month, urine neutrophil gelatinase-associated lipocalin(NGAL) and cytokines related to ischemia-reperfusion injury(IRI). Results: Seventy-one patients were enrolled(36 RLS, 35 NSS+D5W). 64.78% of patients were deceased donor KT(DDKT) recipients. Baseline characteristics were comparable. On postoperative day 4, the RLS group had significantly higher serum bicarbonate(18.9±2.7vs17.5±2.3 mEq/L,p=0.019) and pH (7.41±0.07vs7.37±0.08,p=0.048). Electrolytes level were similar between groups. Among DDKT recipients, RLS was associated with lower urine NGAL(54.5[26.2-108.5]vs151.3[56.4-188.1] ng/mL,p=0.015) and lower proportion of high IFN-γ level(33.3%vs 60%,p=0.044). DGF rates were similar(5.6%vs5.7%,p=0.98). At 1 month, mean SCr was significantly lower in the RLS group(1.29±0.4vs1.58±0.5mg/dL,p=0.007). Conclusion: RLS significantly reduced postoperative metabolic acidosis compared to NSS+D5W and showed evidence of reducing IRI. These findings support RLS as a preferred, low-cost crystalloid for fluid management after KT.Volume of IV fluids