Hillerson, Dustin B

Background There is limited evidence on the epidemiology and prognostic significance of acid-base disorders in the cardiovascular intensive care unit (CICU). This study examines the association of acid-base status at admission with in-hospital mortality among CICU patients. Methods We conducted a retrospective analysis of adults admitted to the Mayo Clinic CICU from 2007-2018 with available blood gas data, utilizing values obtained closest to CICU admission. Arterial pH, serum bicarbonate, base excess, and partial pressure of carbon dioxide (PaCO 2 ) were examined as predictors of in-hospital mortality. Multivariable logistic regression was used to assess associations, with adjustment for demographics, comorbidities, illness severity, and interventions. Results Among 3229 patients included for analysis, acidemia (pH < 7.35) emerged as the strongest predictor of in-hospital mortality (adjusted odds ratio [aOR] 1.60, 95% confidence interval [CI] 1.29-1.98, P < .003). Metabolic acidosis (HCO3 < 20 mEq/L, aOR 1.55, 95% CI 1.24-1.95, P < .001) and respiratory acidosis (PaCO2 > 45 mm Hg, aOR 1.44, 95% CI 1.14-1.81, P = .002) were associated with higher in-hospital mortality, whereas metabolic and respiratory alkalosis were not. After adjustment, lower pH and more negative base excess were associated with higher in-hospital mortality (both P < .001), whereas HCO3 and PaCO2 were not ( P = .053 and P = .051, respectively). Patients with combined metabolic and respiratory acidosis had the highest in-hospital mortality (56.3%). Conclusions Short-term survival in CICU patients decreases progressively with worse acidemia, especially in the context of combined metabolic and respiratory acidosis. Incorporating metabolic acid-base disorders as key therapeutic targets in randomized cardiogenic shock trials may improve outcomes in this complex population by addressing hemometabolic shock.

Abstract Aims Left ventricular (LV) ventricular-arterial coupling (VAC) refers to the ratio of afterload (effective arterial elastance) to contractility (end-systolic elastance) as an integrated marker of cardiac performance. We sought to determine whether the echocardiographic VAC ratio, defined using the ratio of LV end-systolic volume (LVESV) to stroke volume (SV), predicted mortality in the cardiac intensive care unit (CICU). Methods and results Mayo Clinic CICU patients from 2007 and 2018 were included. Ventricular-arterial coupling ratio was calculated as the Teichholz LVESV divided by the SV calculated from LV outflow tract Doppler. The primary outcome was in-hospital mortality and the secondary outcome was all-cause 1-year mortality. A total of 4685 patients were included with a median age of 69 (58, 79) years (37.2% females), with acute coronary syndrome in 54.9% and heart failure in 49.0%. A higher VAC ratio was associated with greater severity of illness, worse echocardiographic findings, and more use of critical care therapies. A total of 329 (7%) patients died during hospitalization. Patients with a higher VAC ratio had higher in-hospital mortality overall and in each admission diagnosis subgroup. After multivariable adjustment, patients with a VAC ratio &gt;2 were at higher risk of in-hospital mortality (adjusted odds ratio 1.63, 95% confidence interval 1.17–2.28, P = 0.010). One-year mortality was higher for patients with a higher VAC ratio, especially VAC &gt;2. Conclusion Ventricular-arterial uncoupling was associated with worse outcomes in an unselected CICU cohort. The echocardiographic VAC ratio is a simple non-invasive bedside measure that can be used for risk prediction in the CICU.