SODium BICarbonate for metabolic acidosis in the Intensive Care Unit: A pilot, multicentre, randomized, double-blind clinical trial

Sodium bicarbonate 8.4% (1000 mEq/L) will be diluted in a 5% dextrose (D5W) solution (500 milliliters bag). For the preparation, 300 mL of D5W will be removed and 300 mL of sodium bicarbonate 8.4% added to prepare the bicarbonate solution in total volume of 500 mL (final concentration: 600 mEq/L).

Allocated study drug will be continuously infused targeting a pH > 7.30 and a base excess (BE) > 0 mEq/L. The infusion will be maintained until this target is achieved and continued by titration thereafter for a maximum of 5 hours to maintain target pH and base excess levels.

The infusion will start at 100 mL/hr and be kept at this rate until both targets (pH and BE) are achieved. Then, once both targets are achieved it will be decreased to 25 mL/hr and kept constant at this infusion rate until 5 hours after the start of the infusion. After 5 hours of the start of the infusion, the infusion will be stopped independently of the results of the arterial blood gas analysis.

Arterial blood gases will be obtained in pre-defined moments within the first 5 hours (at 0, 1 [± 0.1 hours], 3 [± 0.5 hours], and 5 [± 1 hour] hours after the start of the infusion), and then at 12 (± 2 hours), 18 (± 2 hours) and 24 (± 2 hours) hours after the start of the drug infusion. The maximum time of infusion is up to 5 hours after the start of the infusion, until RRT start or ICU discharge, whichever comes first. Open-label sodium bicarbonate infusion is allowed if clinically indicated.