Impact of Colloid Cardiopulmonary Bypass Priming Strategy on Perioperative Acid-Base Balance in Coronary Artery Bypass Surgery: Physicochemical Analysis of a Double-Blinded Randomized Controlled Study.

Authors

Rohan Boer, Anne M Beukers, Jiska M Pols, Jord C Seegers, Nikki van Haasteren, Dany Ghantous, Rens Nieuwenhuizen, Meike Brouwers, Carolien S E Bulte, František Duška, Alexander B A Vonk, Stephan A Loer, Micah L A Heldeweg, PRIME study group

Published in

Journal of cardiothoracic and vascular anesthesia. Aug 29, 2026. Epub Aug 29, 2026.

Abstract

To determine whether colloid choice within the cardiopulmonary bypass (CPB) priming strategy independently modifies the perioperative acid-base trajectory.
Preplanned analysis of a single-center, double-blind, 3-arm randomized controlled trial.
A tertiary academic teaching hospital.
Thirty-four adult patients undergoing elective coronary artery bypass grafting with CPB.
Patients were randomized 1:1:1 to 3 priming strategies (total 1500 mL): albumin-based, gelofusine-based, and retrograde autologous priming (reference group).
Acid-base status was characterized using Stewart's physicochemical approach at 5 perioperative time points (postinduction to 24 hours post-intensive care unit admission). A linear mixed model was used to assess the effects of priming strategy, time, and additional crystalloids. Across 170 observations, initiation of CPB induced substantial metabolic acidosis (-0.1 pH, -4.3 mmol/L standard base excess, -6.6 mEq/L effective strong ion difference), driven by reductions in apparent strong ion difference and persisting at 24 hours. pH, standard base excess, and effective strong ion difference did not differ among the priming strategies. Albumin attenuated weak acid-anion dilution (+0.79 mEq/L; p = 0.037), while gelofusine increased the strong ion gap (+2.19 mEq/L; p < 0.001). Each additional liter of crystalloid independently lowered pH (-0.011; p = 0.035), standard base excess (-0.99 mmol/L; p = 0.022), and effective strong ion difference (-1.03 mEq/L; p = 0.025), driven by a rise in strong ion gap (+1.24 mEq/L; p = 0.001).
CPB-induced metabolic acidosis is driven predominantly by reductions in apparent strong ion difference and sustained by unbalanced crystalloid load rather than by colloid choice. Acid-base optimization should prioritize balanced, strong ion difference-guided priming fluid and crystalloid strategies over colloid selection.

PMID:
42791111
Bibliographic data and abstract were imported from PubMed on 26 Sep 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.