The impact of prolonged mechanical ventilation after acute type A aortic dissection repair

Patients with type A aortic dissection have increased resource use. The objective of this study was to describe the relationship between prolonged mechanical ventilation and longitudinal survival in patients undergoing type A aortic dissection repair.

We conducted a retrospective analysis of patients with type A aortic dissection undergoing repair from 2010 to 2018; Kaplan-Meier function and adjusted Cox regression analysis were used to compare in-hospital mortality and longitudinal survival accounting for time on mechanical ventilatory support.

A total of 552 patients were included. The study population was divided into 12 hours or less (n = 291), more than 12 to 24 or less hours (n = 101), more than 24 to 48 hours or less (n = 60), and more than 48 hours (n = 100) groups. Patients within the 12 or less hours group were the youngest (60.0 vs 63.5 years vs 63.6 vs 62.8 years; P = .03) and less likely to be female (31.6% vs 43.6% vs 46.7% vs 56.0%; P < .001). On the other hand, the more than 48 hours group presented with malperfusion syndrome at admission more often (24.4% vs 29.7% vs 28.3% vs 53.0%; P < .001) and had longer cardiopulmonary and ischemic times (P < .05). In-hospital mortality was significantly higher in the more than 48 hours group (5.2% vs 6.9% vs 3.3% vs 30.0%; P < .001). Multivariable analysis demonstrated worse longitudinal survival for the 24 to 48 hours group (hazard ratio, 1.94, confidence interval, 1.10-3.43) and more than 48 hours ventilation group (hazard ratio, 2.25, confidence interval, 1.30-3.92).

The need for prolonged mechanical ventilatory support is prevalent and associated with other perioperative complications. More important, after adjusting for other covariates, prolonged mechanical ventilation is an independent factor associated with increased longitudinal mortality.