Sodium bicarbonate of no help in metabolic acidemia, acute kidney injury

Intravenous treatment with sodium bicarbonate does not appear to confer survival benefits in patients with severe metabolic acidemia and moderate to severe acute kidney injury, as shown in a study.

The study included 640 patients (median age 67 years, 59.2 percent male) with severe metabolic acidemia (defined as pH ≤7.20) and moderate to severe acute kidney injury (defined as stage 2 or 3 on the KDIGO classification). These patients were randomly assigned to receive either sodium bicarbonate infusion (n=314) or no sodium bicarbonate (control, n=313) to target an arterial pH of ≥7.30.

The primary outcome was 90-day all-cause mortality. Secondary outcomes included all-cause mortality at days 28 and 180; use of organ support therapy, vasopressors, or invasive mechanical ventilation; intensive care unit and hospital length of stay; intensive care unit–acquired infections; fluid balance; day-7 Sequential [Sepsis-related] Organ Failure Assessment score (6 organ systems’ function is evaluated and scored from 0 [no dysfunction] to 4 [failure]; total score ranges from 0 [normal] to 24 [maximum failure]); and major adverse kidney events on day 90.

In the primary analysis, all-cause mortality at day 90 did not significantly differ between the bicarbonate and control groups, at 62.1 percent vs 61.7 percent (absolute difference, 0.4, 95 percent confidence interval [CI], −7.2 to 8.0; p=0.91), respectively. All-cause mortality at days 28 and 180 was also similar between the two groups.

Kidney replacement therapy was used in fewer patients in the bicarbonate group than in the control group (35 percent vs 50 percent; absolute difference, −15.5, 95 percent CI, −23.1 to −7.8). No significant between-group differences were noted in other secondary outcomes, including adverse events.