Physicochemical effects of bicarbonate-buffered solution versus compound sodium lactate during major abdominal surgery: A randomized, open-label, non-inferiority trial
5 affiliations
- 1Department of Intensive Care, Austin Health, Melbourne, Australia
- 2Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, Australia
- 3Department of Anaesthesia, Austin Health, Melbourne, Australia
- 4Department of Critical Care, The University of Melbourne, Melbourne, Australia
- 5Department of Anesthesiology and Pain Medicine, Dongguk University Ilsan Hospital, Goyang, Republic of Korea
Abstract
Introduction: Bicarbonate-buffered crystalloids avoid exogenous lactate and have physicochemical properties distinct from compound sodium lactate (CSL), but direct comparative evidence during major abdominal surgery remains limited. Methods: This single-center, open-label, randomized non-inferiority trial enrolled high-risk adults undergoing elective major abdominal surgery. Participants received bicarbonate-buffered solution or CSL as the allocated intraoperative crystalloid. The primary estimand was the arithmetic mean difference in standard base excess (SBE) at skin closure (bicarbonate-buffered solution minus CSL). The non-inferiority margin was −1.5 mEq/L. The trial was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12619001228178). Results: Fifty participants were randomized (25 per group) and received their allocated intervention. End-of-surgery arterial blood gas data were missing for two CSL participants. In the intention-to-treat analysis using multiple imputation, the estimated mean difference in end-of-surgery SBE was −0.42 mEq/L (95% confidence interval [CI], −1.92 to 1.09 mEq/L). The complete-case per-protocol estimate was −0.48 mEq/L (95% CI, −2.02 to 1.06 mEq/L). In both analyses, the lower CI bound was below the prespecified non-inferiority margin; non-inferiority was not established. Secondary outcomes were exploratory; observed end-of-surgery lactate was lower with bicarbonate-buffered solution (median 0.9 vs 1.2 mmol/L; unadjusted P = 0.031), without a corresponding difference in SBE or pH. Conclusions: In this small trial of hemodynamically stable adults undergoing elective major abdominal surgery, the primary non-inferiority result was inconclusive. The data did not establish interchangeability, equivalence, superiority, or inferiority of the two fluids. As the trial was powered for a physiologic endpoint, no comparative inference can be made about organ dysfunction, postoperative complications, recovery, or mortality. Larger trials with standardized co-interventions and patient-important outcomes are required before routine substitution for CSL can be recommended.
Related
- Non-Inferiority Margins in Randomized Controlled Trials in Abdominal Surgery- a Systematic Review
- Dose-dependent effects of sodium bicarbonate supplementation combined with sprint interval training on performance adaptations in basketball players: a randomized placebo-controlled trial
- A randomized trial of high versus low serum bicarbonate targets and glomerular filtration rate decline in stage 3–4 chronic kidney disease
- A randomized double-blind non-inferiority trial comparing LUCENTRA with DYSPORT for moderate-to-severe glabellar line improvement
- Randomized non-inferiority within-patient trial of density gradient processing of sequential ejaculates versus centrifugation-free sperm separation device for ICSI in men with elevated sperm DNA fragmentation- study protocol
BibTeX
@article{yanase2026physicochemical,
title = {{Physicochemical effects of bicarbonate-buffered solution versus compound sodium lactate during major abdominal surgery: A randomized, open-label, non-inferiority trial}},
author = {Fumitaka Yanase and Laurence Weinberg and Varun Peri and Je Min Suh and Rebecca Caragata and Gabriel Lirios and Bradly Carp and Michael Jiang and Qui Rui Soh and Shervin Tosif and Glenn Eastwood and Rinaldo Bellomo and Dong Kyu Lee},
journal = {PLOS One},
year = {2026},
month = sep,
doi = {10.1371/journal.pone.0356619},
url = {https://doi.org/10.1371/journal.pone.0356619},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Physicochemical effects of bicarbonate-buffered solution versus compound sodium lactate during major abdominal surgery: A randomized, open-label, non-inferiority trial
AU - Fumitaka Yanase
AU - Laurence Weinberg
AU - Varun Peri
AU - Je Min Suh
AU - Rebecca Caragata
AU - Gabriel Lirios
AU - Bradly Carp
AU - Michael Jiang
AU - Qui Rui Soh
AU - Shervin Tosif
AU - Glenn Eastwood
AU - Rinaldo Bellomo
AU - Dong Kyu Lee
PY - 2026
DA - 2026/09/09
JO - PLOS One
DO - 10.1371/journal.pone.0356619
UR - https://doi.org/10.1371/journal.pone.0356619
AB - Introduction: Bicarbonate-buffered crystalloids avoid exogenous lactate and have physicochemical properties distinct from compound sodium lactate (CSL), but direct comparative evidence during major abdominal surgery remains limited. Methods: This single-center, open-label, randomized non-inferiority trial enrolled high-risk adults undergoing elective major abdominal surgery. Participants received bicarbonate-buffered solution or CSL as the allocated intraoperative crystalloid. The primary estimand was the arithmetic mean difference in standard base excess (SBE) at skin closure (bicarbonate-buffered solution minus CSL). The non-inferiority margin was −1.5 mEq/L. The trial was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12619001228178). Results: Fifty participants were randomized (25 per group) and received their allocated intervention. End-of-surgery arterial blood gas data were missing for two CSL participants. In the intention-to-treat analysis using multiple imputation, the estimated mean difference in end-of-surgery SBE was −0.42 mEq/L (95% confidence interval [CI], −1.92 to 1.09 mEq/L). The complete-case per-protocol estimate was −0.48 mEq/L (95% CI, −2.02 to 1.06 mEq/L). In both analyses, the lower CI bound was below the prespecified non-inferiority margin; non-inferiority was not established. Secondary outcomes were exploratory; observed end-of-surgery lactate was lower with bicarbonate-buffered solution (median 0.9 vs 1.2 mmol/L; unadjusted P = 0.031), without a corresponding difference in SBE or pH. Conclusions: In this small trial of hemodynamically stable adults undergoing elective major abdominal surgery, the primary non-inferiority result was inconclusive. The data did not establish interchangeability, equivalence, superiority, or inferiority of the two fluids. As the trial was powered for a physiologic endpoint, no comparative inference can be made about organ dysfunction, postoperative complications, recovery, or mortality. Larger trials with standardized co-interventions and patient-important outcomes are required before routine substitution for CSL can be recommended.
SN - 1932-6203
ER -