Summary

Background and objectives: Sodium bicarbonate is the most physiological alkalinizing agent. The effect of a new bicarbonated Ringer's solution (BRS) containing Mg2+, on metabolic acidosis and serum magnesium abnormality were evaluated and compared with those of acetated Ringer's (ARS), lactated Ringer's (LRS) and Ringer's (RS) solutions in an experimental haemorrhagic shock model with dogs. Methods: Animals were randomly divided into six groups (n = 6 in each group), a sham-operated group, an operated group without infusion, and 4 operated groups with infusion (BRS, ARS, LRS and RS groups). Each RS was intravenously administered at 60 mL kg−1 h−1 for 1.5 h. Arterial blood gases, plasma electrolytes and cardiovascular parameters were analysed. Results: BRS significantly improved blood base excess values, which were decreased by blood-letting, faster and more markedly than did LRS and RS (BRS −6.3 ± 0.5 mEq L−1; LRS −9.2 ± 1.1 mEq L−1; RS −12.4 ± 1.0 mEq L−1 at the end of infusion). The alkalinizing effect of BRS tended to be better than that of ARS but not significantly so. The serum Mg2+ concentration was well-maintained by BRS as compared to other RS (BRS 1.5 ± 0.0 mg dL−1; ARS 1.2 ± 0.0 mg dL−1; LRS 1.1 ± 0.0 mg dL−1; RS 1.3 ± 0.1 mg dL−1, at the end of infusion). Conclusions: These results suggest that BRS is a suitable perioperative solution for metabolic acidosis and serum electrolyte balance among RS tested.