Abstract 4137205: Management Patterns and Outcomes in the Use of Invasive Mechanical Ventilation for Patients with Cardiogenic Shock

Abstract

Background: Approximately half of all patients with cardiogenic shock (CS) require invasive mechanical ventilation (IMV). While there have been significant advances in the management of patients requiring IMV based on data primarily derived from medical intensive care patients with respiratory failure, little is known regarding the management and outcomes of IMV in patients with CS. Methods: We conducted an analysis of patients treated for CS who required IMV at an academic safety net hospital from 2017-2023. Indications for IMV, ventilator settings, and medications were obtained from the medical record. The primary outcome was unsuccessful extubation, defined as reintubation within 48 hours of extubation. Results: A total of 110 patients with CS who received IMV were identified. Median age was 60yo; 28% of the cohort was female, 39% of Hispanic ethnicity, and 38% of Black race. Primary reasons for intubation included ongoing cardiac arrest (35%) and hypoxic respiratory failure (34%). Most patients were on minimal ventilator support at 24 hours after intubation (median FiO2 40% [IQR 30-50%], post-end expiratory pressure [PEEP] 5cm H2O [IQR 5-8]). Mechanical circulatory support (MCS) was present in 40% of patients at 24 hours post-intubation. Protocolized spontaneous breathing trials (SBTs) were delayed in 77% of patients, primarily due to hemodynamic instability (88%). Planned or unplanned extubation occurred in 63% of patients after a median of 4.8 days [IQR 2.1-8.0]. Ten percent of patients transferred hospitals while on IMV, while 27% were palliatively extubated or died on IMV. The majority (58%) of patients undergoing non-palliative extubation were on vasoactive medications preceding extubation, with only 2% on MCS. Most patients (58%) were extubated to nasal cannula or room air. A total of 13% of patients experienced unsuccessful extubation. Conclusions: In a cohort of patients with CS requiring IMV, most patients were on minimal ventilator settings within 24 hours yet remained intubated with SBTs delayed due to hemodynamic instability. Rates of failed extubation were comparable to published data from other forms of critical illness. Further work is necessary to determine optimal approaches to ventilator liberation and circulatory support in intubated patients with CS where hemodynamic derangements rather than respiratory insufficiency represent the primary barrier to extubation.