Comparison of the Effects Between Ringers and Ringers Lactate Administration as the Prime Solution on Perioperative Acid-Base Status in Pediatric Patients With Non-Cyanotic Diseases Undergoing Cardiac Surgeries

Background: The solutions used to prepare the cardiopulmonary bypass (CPB) circuit are known to constitute some of the potential causes of metabolic acidosis at the onset of CPB. Solutions containing lactate, acetate, and other anions have a buffering effect owing to the metabolism of these anions into bicarbonate ions. Hence, the administration of lactate-containing solutions to children may lead to elevated serum lactate levels. Methods: The present double-blind randomized clinical trial evaluated 50 non-cyanotic pediatric patients (2 groups of 25 cases) aged between 12 and 48 months undergoing cardiac surgeries. Ringers solution and Ringers lactate solution were each used in 1 study group as the CPB prime solution. The levels of pH, bicarbonate, base excess (BE), lactate, calcium, glucose, chloride, and arterial blood gas were measured at 4 different time points: before the initiation of CPB (T0) and then 5 (T1), 30 (T2), and 60 (T3) minutes after bypass commencement. Results: The levels of pH at T1 and T2 were statistically different between the 2 groups (P=0.029 and P=0.001, respectively). The 2 groups were also statistically meaningfully different concerning T2 BE (P<0.0001). The mean HCO- 3 levels at T2 and T3 were statistically different between the groups (P<0.0001 and P=0.039, respectively). Lactate levels at T1 and T2 statistically significantly differed between the 2 groups (P<0.0001 and P=0.017, respectively). Conclusions: The current study showed that Ringers lactate solution as the CPB prime solution was more effective than Ringers solution in reducing CPB-induced acidosis without increasing the circulatory lactate level. (Iranian Heart Journal 2023; 24(3): 6-14)