For decades, sodium bicarbonate has been administered during cardiac arrest resuscitation based on physiological logic — if you can neutralize the severe metabolic acidosis that accumulates when circulation stops, you should restore cardiac function and improve survival odds. This trial puts that assumption under rigorous scrutiny, and the results are sobering for a widely used intervention.
The BICAR-ICU-adjacent Bicarbonate for In-Hospital Cardiac Arrest trial enrolled 779 patients experiencing in-hospital cardiac arrest and randomized them to receive either routine intravenous sodium bicarbonate or placebo during resuscitation attempts. The primary endpoint — return of spontaneous circulation — occurred in 39% of the bicarbonate group versus 37% of controls, a difference that was not statistically significant. Secondary outcomes told a similarly flat story: 30-day survival (12% vs. 9%), organ dysfunction within 72 hours, functional recovery scores, and quality-of-life measures showed no meaningful divergence between groups. Crucially, biochemical markers confirmed the drug was working as intended — survivors in the bicarbonate arm showed measurably higher blood pH and bicarbonate concentrations — yet this physiological correction translated into no clinical advantage.
This finding is clinically important because it illustrates a persistent trap in medicine: physiological plausibility does not equal clinical efficacy. Correcting acidosis makes mechanistic sense, and the drug does correct it, but the downstream benefit never materializes. This mirrors earlier negative findings from smaller trials and observational data that already cast doubt on routine bicarbonate use. The trial is reasonably powered for a cardiac arrest study, though 30-day survival at roughly 10% underscores how heterogeneous and high-mortality this population is, limiting subgroup precision. The study applies specifically to in-hospital arrests — where response times and monitoring differ substantially from out-of-hospital settings — so generalizability has boundaries. Overall, this represents a confirmatory rather than paradigm-shifting result, but at adequate scale it may finally shift guidelines away from reflexive bicarbonate administration during resuscitation.