Pre-Existing Right Ventricular Dysfunction as an Independent Risk Factor for Post Intubation Cardiac Arrest and Hemodynamic Instability in Critically Ill Patients: A Retrospective Observational Study

Background: Post intubation cardiac arrest and hemodynamic instability are serious adverse events encountered in critically ill patients. The association of pre-existing right ventricular (RV) dysfunction with post intubation cardiac arrest and hemodynamic instability in critically ill patients is unknown. Methods: This is a retrospective matched cohort study of adult critically ill patients who underwent intubation from July 2016 to December 2019. The study was conducted at a quaternary medical center in Houston, Texas. A total of 340 critically ill patients who underwent intubation in the intensive care units, wards, and the emergency room were included. The study cohort was categorized into 4 groups based on the pre-existing RV function: normal function, mild dysfunction, moderate dysfunction, and severe dysfunction. Cardiac arrest and/or hemodynamic instability within one hour post intubation were the primary study outcomes. Secondary outcomes included in hospital and 60-day mortality. Results: Study patients were of mean age of 61.95 ± 14.28 years, including 132 (39%) females and 208 (61%) males. The primary outcomes were significantly worse in mild, moderate, and severe RV dysfunction groups compared to the normal RV function group (34.12%-P = 0.014, 47.06%-P < 0.001, 51.67%-P < 0.001, vs. 17.56%). In a multivariable logistic regression analysis, pre-existing moderate (OR = 2.65, P = 0.013) and severe RV dysfunction groups (OR = 2.66, P = 0.015) were associated with statistically significant higher cardiac arrest and hemodynamic instability post intubation. Pre-existing severe RV dysfunction was associated with statistically significant higher in hospital mortality (62.35%-P < 0.001). The multivariable Cox-regression analysis showed that pre-existing severe RV dysfunction was associated with a statistically significant higher 60-day mortality (HR = 2.57, P = 0.001). Conclusions: Pre-existing moderate and severe RV dysfunctions were independently associated with significantly higher cardiac arrest and/or hemodynamic instability post intubation in critically ill patients. Pre-existing RV function may serve as a mortality predictor in critically ill patients undergoing endotracheal intubation.