The Efficacy of Sodium Bicarbonate Ringer's Solution and Lactate Ringer's Solution in Patients Undergoing Long-Term Abdominal Open Surgery: A Multicenter Prospective Randomized Controlled Study.

Abstract

Purpose: Sodium bicarbonate Ringer's solution (BRS) is an intravenous fluid that does not rely on hepatic or renal metabolism. It contains bicarbonate ions (HCO₃ ^-) and lacks lactate ions. This study hypothesizes that BRS is more effective in maintaining acid-base balance during prolonged open abdominal surgeries. The aim is to investigate the effects of sodium bicarbonate Ringer's solution on lactate metabolism, acid-base balance, and clinical outcomes in patients undergoing extended-duration open abdominal surgery, with the objective of refining fluid replacement strategies for this patient population.

Patients and methods: A multicenter randomized controlled trial was conducted involving 112 patients undergoing open abdominal surgery. Participants were randomly assigned to either the BRS group (n=55) or the lactated Ringer's solution (LRS) group (n=57). The primary outcome was the incidence of postoperative hyperlactacidemia, while secondary outcomes included serum lactate (Lac), pH, base excess (BE), buffered base (BB), bicarbonate (HCO₃ ^-), blood glucose (Glu), electrolytes, postoperative liver and kidney function, and postoperative complications. Linear regression analysis was performed to identify factors influencing lactate concentration.

Results: The incidence of hyperlactic acidemia was lower in Group A compared to Group B (9.1% vs 19.3%, P = 0.177), although the difference did not reach statistical significance. No significant differences were observed in lactate (Lac), pH, base excess (BE), bicarbonate (BB), HCO₃⁻, glucose (Glu), or electrolytes between the two groups at any time point (P _time < 0.001, P _group > 0.05, P _{time * group} > 0.05). Linear regression analysis revealed that diabetes, hypotension and blood loss were significant factors influencing blood lactate concentration (R² = 0.349, P < 0.001).

Conclusion: Sodium bicarbonate Ringer's solution and lactate Ringer's solution are both safe options for fluid replacement during long-term open abdominal surgeries. There is no significant difference observed in perioperative lactate levels, acid-base balance, or clinical postoperative outcomes between the two solutions.