Clinical question: Does sodium bicarbonate treatment improve clinical outcomes in critically ill patients with severe metabolic acidosis?
Background: Severe acidemia is associated with impaired cardiac function, decreased perfusion, and increased mortality. Many physicians use sodium bicarbonate to improve hemodynamic stability in critically ill patients with acidemia. However, the use of sodium bicarbonate in this role remains controversial because the evidence to support it is limited.
Study design: Multicenter, open-label, randomized, controlled trial.
Setting: Twenty-six ICUs in France.
Synopsis: Investigators randomized 389 adult patients with severe acidemia and Sequential Organ Failure Assessment (SOFA) scores of 4 or greater or serum lactate level of 2 mmol/L or greater to receive either no sodium bicarbonate or 4.2% intravenous sodium bicarbonate. The primary composite outcome was at least organ failure at day 7 or mortality by day 28.
When compared as a whole, the treatment group did not demonstrate improvement in the primary outcome. However, patients with Acute Kidney Injury Network scores of 2 or 3 at enrollment who received bicarbonate had lower rates of the composite primary outcome (70% vs. 82%; P = .462). Additionally, 35% of the treatment group utilized a renal replacement therapy (RRT) during their ICU stay versus 52% of the control group (P = .0009).
Limitations of the study included unblinding of the ICU physicians and the lack of a control intravenous solution. Notably, 47 of the 194 patients in the control group received sodium bicarbonate as salvage therapy.
Bottom line: Sodium bicarbonate treatment may decrease the need for RRT in patients with significant metabolic acidemia and may decrease the likelihood of death or organ failure in those with severe acute kidney injury.
Citation: Jaber S et al. Sodium bicarbonate therapy for patients with severe metabolic acidaemia in the intensive care unit (BICAR-ICU): A multicentre, open-label, randomised controlled, phase 3 trial. Lancet. 2018;392(10141):31-40.
Dr. James is a hospitalist at Emory University Hospital Midtown and an assistant professor at Emory University, both in Atlanta