Effects of intraoperative and early postoperative normal saline or Plasma-Lyte 148® on hyperkalaemia in deceased donor renal transplantation: a double-blind randomized trial.

BACKGROUND: Administration of saline in renal transplantation is associated with hyperchloraemic metabolic acidosis, but the effect of normal saline (NS) on the risk of hyperkalaemia or postoperative graft function is uncertain.

METHODS: We compared NS with Plasma-Lyte 148® (PL) given during surgery and for 48 h after surgery in patients undergoing deceased donor renal transplantation. The primary outcome was hyperkalaemia within 48 h after surgery. Secondary outcomes were need for hyperkalaemia treatment, change in acid-base status, and graft function.

RESULTS: Twenty-five subjects were randomized to NS and 24 to PL. The incidence of hyperkalaemia in the first 48 h after surgery was higher in the NS group; 20 patients (80%) vs 12 patients (50%) in the PL group (risk difference: 0.3; 95% confidence interval: 0.05, 0.55; P=0.037). The mean (sd) peak serum potassium was NS 6.1 (0.8) compared with PL 5.4 (0.9) mmol litre-1 (P=0.009). Sixteen participants (64%) in the NS group required treatment for hyperkalaemia compared with five (21%) in the PL group (P=0.004). Participants receiving NS were more acidaemic [pH 7.32 (0.06) vs 7.39 (0.05), P=0.001] and had higher serum chloride concentrations (107 vs 101 mmol litre-1, P<0.001) at the end of surgery. No differences in the rate of delayed graft function were observed. Subjects receiving PL who did not require dialysis had a greater reduction in creatinine on day 2 (P=0.04).

CONCLUSIONS: Compared with PL, participants receiving NS had a greater incidence of hyperkalaemia and hyperchloraemia and were more acidaemic. These biochemical differences were not associated with adverse clinical outcomes.

CLINICAL TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12612000023853.