International Journal of Cardiovascular Sciences. 29/Apr/2025;38:e20240236.

Mechanical Ventilation Time and Mortality After Coronary Artery Bypass Grafting: A Cohort Study

Tainá Lís de Araujo Dezidério , Vanessa Oliveira da Silva , Vitória Novaes Macedo , André Luiz Lisboa Cordeiro

DOI: 10.36660/ijcs.20240236

This Original Article is referred by the Editorial "Mechanical Ventilation: Friend or Foe in Cardiac Surgery?".

Abstract

Introduction:

Cardiac surgery is a procedure that requires great assistance and care. In this way, patients are sent to the intensive care unit (ICU), where they are connected to mechanical ventilation (MV). Prolonged treatment of these patients worsens clinical outcomes and leads to mortality.

Objective:

To evaluate the impact of MV time on patients undergoing cardiac surgery.

Methods:

This is a retrospective cohort study. After surgery, patients were admitted to the ICU and connected to MV. The entire ventilation adjustment and weaning process was conducted according to the unit’s routine. They were divided into two groups, patients who continued on MV for more than eight hours and those who remained for less than eight hours. From this, univariate and multivariate analyses were carried out between predictor variables — MV time, age, sex, and cardiopulmonary bypass (CPB) time — and mortality. We considered p<0.05 as significant.

Results:

A total of 110 patients were evaluated, 25 stayed on MV for more than eight hours. In the univariate analysis, MV time was associated with mortality (HR 0.7 [0.3–0.9], p = 0.01), remaining in the multivariate analysis (HR 0.4 [0.2–0.6), p = 0.01). The other variables were not associated with death outcome.

Conclusion:

MV time of more than eight hours is a predictor of mortality after cardiac surgery, given the contribution of some risk factors.