Respiratory Support and Mortality Risk Across the Spectrum of Cardiogenic Shock Severity

The Society for Cardiovascular Angiography & Intervention (SCAI) SHOCK stages classification schema risk-stratifies patients with cardiogenic shock (CS). The updated 2022 SCAI SHOCK stages removed the use of respiratory support, either noninvasive (NIV) or invasive mechanical ventilation (IMV), as a criterion. We sought to investigate the impact of receiving respiratory support on in-hospital mortality for patients with CS stratified by SCAI SHOCK stages.

Utilizing a nationally representative database, adults aged ≥18 years admitted from 2015 to 2023 with a diagnosis of CS were used to assess for the association between respiratory support, either NIV or IMV, on the first day of admission, with in-hospital mortality stratified by SCAI SHOCK stages B through E. We utilized inverse probability treatment weighting, adjusting for demographic characteristics, comorbidities, hospital characteristics, and vasoactive/mechanical circulatory support.

We identified 317,325 patients with CS, including 2.4%, 39.0%, 34.2%, and 24.5% with SCAI stages B through E, respectively. Respiratory support was utilized in 38.0% (n = 120,594) of patients, with 5.4% receiving NIV, 33.8% receiving IMV, and 1.1% receiving both on the first day of admission. After inverse probability treatment weighting, respiratory support use remained associated with an increased mortality overall (weighted mean mortality increase of 18.3%; 95% CI, 17.9%-18.7%), when stratified by each SCAI SHOCK stage and in several key sensitivity analyses.

Compared with patients not receiving respiratory support, the use of respiratory support was associated with an increased mortality for each SCAI stage of CS and could be a simple, easily identifiable CS risk modifier.