Effects of sodium bicarbonate infusion on mortality in medical–surgical ICU patients with metabolic acidosis—A single-center propensity score matched analysis / Efectos de la infusión de bicarbonato de sodio sobre la mortalidad en pacientes de UCI médico-quirúrgica con acidosis metabólica: un análisis de puntuación de propensión en un solo Centro

Objective Metabolic acidosis is associated with high mortality. Despite theoretical benefits of sodium-bicarbonate (SB), current evidence remains controversial. We investigated SB-related effects on outcomes in ICU patients with metabolic acidosis. Design Retrospective analysis. Setting Academic medical center. Patients or participants 971 ICU patients with metabolic acidosis defined as arterial pH<7.3 and CO2<45mmHg treated between 2012 and 2016. A propensity score (PS) was estimated using logistic regression. Patients were matched in pairs using the PS. Interventions 441 patients were treated with SB 8.4% (SB-group) and n=530 patients were not (control group). Main variables of interest Primary outcome was all-cause mortality at ICU-discharge. Average Treatment Effect (ATE), Average Treatment effect in Treated (ATT), and estimated relative survival effects at 20 days were computed. Results In the full cohort, we observed considerable differences in pH, base excess, additional acidosis-related indices, and ICU mortality (controls 31% vs. SB-group 56%, p<.001) at baseline between the two groups. After PS-matching (n=174 in each group), no significant difference in ICU mortality was observed (controls 32% vs. SB-group 41%; p=.07). Odds ratios (OR) for ATE and ATT showed no association with ICU mortality (OR ATE: 1.08, 95%-CI 0.99–1.17; p=.08; OR ATT 1.09; 95%-CI 0.99–1.2; p=.09). Hazard ratios at 20-days (multivariable HR, matched sample n=348: 1.16, 95%-CI 0.86–1.56, p=.33) showed similar survival in the two study groups. Conclusions We did not observe effects of SB infusion on all-cause mortality in critically ill patients with metabolic acidosis (AU)

Objetivo La acidosis metabólica se asocia con una alta mortalidad. A pesar de los beneficios teóricos del bicarbonato de sodio (BS), la evidencia actual sigue siendo controvertida. Investigamos los efectos relacionados con el BS sobre los resultados en pacientes de la UCI con acidosis metabólica. Diseño Análisis retrospectivo. Ÿmbito Centro médico académico. Pacientes o participante Se incluyeron 971 pacientes de la Unidad de Cuidados Intensivos (UCI) con acidosis metabólica (pH < 7,3, CO2 < 45 mmHg) tratados entre 2012 y 2016. Se calculó una puntuación de propensión (PS) mediante regresión logística. Los pacientes se emparejaron utilizando el PS. Variables de interés principales Intervenciones; 441 pacientes fueron tratados con BS 8,4% (grupo BS) y n = 530 pacientes no (grupo control). Resultados El resultado primario fue la mortalidad por todas las causas al alta de la UCI. Se calcularon el efecto promedio del tratamiento (ATE), el efecto promedio del tratamiento en los tratados (ATT) y los efectos de supervivencia relativa estimados a los 20 días. En la cohorte completa se observaron diferencias considerables en el pH, el exceso de bases y la mortalidad en la UCI (control 31% vs. grupo BS 56%, p < 0,001) al inicio del estudio entre los grupos. Después del emparejamiento de PS (n = 174 en cada grupo), no se observaron diferencias significativas en la mortalidad en la UCI (control 32% vs. grupo BS 41%; p = 0,07). Los odds ratios (OR) para ATE y ATT no mostraron asociación con la mortalidad en la UCI (OR ATE: 1,08, IC 95%; 0,99-1,17; p = 0,08; OR ATT 1,09; IC 95%; 0,99-1,2; p = 0,09). Los cocientes de riesgo a los 20 días (HR multivariable, muestra emparejada n = 348: 1,16, IC 95%; 0,86-1,56, p = 0,33) mostraron una supervivencia comparable. Conclusiones No observamos efectos de la infusión de BS sobre la mortalidad por todas las causas en pacientes con acidosis metabólica (AU)

Effects of sodium bicarbonate infusion on mortality in medical-surgical ICU patients with metabolic acidosis-A single-center propensity score matched analysis.

OBJECTIVE: Metabolic acidosis is associated with high mortality. Despite theoretical benefits of sodium-bicarbonate (SB), current evidence remains controversial. We investigated SB-related effects on outcomes in ICU patients with metabolic acidosis. DESIGN: Retrospective analysis. SETTING: Academic medical center. PATIENTS OR PARTICIPANTS: 971 ICU patients with metabolic acidosis defined as arterial pH<7.3 and CO2<45mmHg treated between 2012 and 2016. A propensity score (PS) was estimated using logistic regression. Patients were matched in pairs using the PS. INTERVENTIONS: 441 patients were treated with SB 8.4% (SB-group) and n=530 patients were not (control group). MAIN VARIABLES OF INTEREST: Primary outcome was all-cause mortality at ICU-discharge. Average Treatment Effect (ATE), Average Treatment effect in Treated (ATT), and estimated relative survival effects at 20 days were computed. RESULTS: In the full cohort, we observed considerable differences in pH, base excess, additional acidosis-related indices, and ICU mortality (controls 31% vs. SB-group 56%, p<.001) at baseline between the two groups. After PS-matching (n=174 in each group), no significant difference in ICU mortality was observed (controls 32% vs. SB-group 41%; p=.07). Odds ratios (OR) for ATE and ATT showed no association with ICU mortality (OR ATE: 1.08, 95%-CI 0.99-1.17; p=.08; OR ATT 1.09; 95%-CI 0.99-1.2; p=.09). Hazard ratios at 20-days (multivariable HR, matched sample n=348: 1.16, 95%-CI 0.86-1.56, p=.33) showed similar survival in the two study groups. CONCLUSIONS: We did not observe effects of SB infusion on all-cause mortality in critically ill patients with metabolic acidosis.