Comparison of effect of Ringer's lactate and isotonic bicarbonate combination therapy with Ringer's lactate alone in early fluid resuscitation of burns patients - A randomised controlled trial.

BACKGROUND

Severe burns cause systemic inflammatory response, capillary leak, and profound metabolic acidosis from both lactic and non-lactic acid sources. Ringer's lactate (RL) remains the resuscitation standard but isotonic bicarbonate (IB, SID ≈ 150) provides superior alkalinizing capacity. This trial evaluated whether combining IB with RL in a 1:1 ratio improves perfusion compared to RL in early burn resuscitation.

METHODS

In this single-centre randomized controlled trial, 134 adult patients with ≥ 15 % TBSA burns presenting within 12 h were randomized to receive RL (2 ml/kg/%TBSA; n = 67) or IB+RL (1:1, 2 ml/kg/%TBSA; n = 67) guided by the modified Brooke formula. The primary outcome was 24-hour lactate reduction. Secondary outcomes included acid-base parameters, electrolytes, glucose-insulin profile, renal function, vasopressor use, SOFA scores, and 7-day mortality. Multiplicity correction was applied for secondary endpoints.

RESULTS

Median 24-hour lactate reduction was similar between RL [45.9 % (29.1-56.6)] and IB+RL [42.7 % (32.7-58.1); p = 0.752]. Conventional acid-base parameters were comparable, but IB+RL showed greater improvement in standard base excess (BE), alactic base excess (aBE), ΔaBE, ΔeSID, and ΔHCO₃⁻; only ΔHCO₃⁻ and ΔaBE retained borderline significance after multiplicity correction. Electrolyte trends included more hypokalemia and hypocalcemia in IB+RL. Glucose trended higher with IB+RL, but insulin requirements and osmolality remained similar. Fluid requirements, urine output, AKI incidence, vasopressor use, SOFA scores, and 7-day mortality were comparable.

CONCLUSION

Adding IB to RL did not improve perfusion but showed exploratory acid-base benefits without excess harm. Findings are hypothesis-generating and warrant validation in larger multicentre trials with individualized bicarbonate strategies.