Our objective was to identify factors associated with the duration of mechanical ventilation (MV) postoperative to cardiac surgery and assess the association between duration of endotracheal intubation, length of stay in the Intensive Care Unit (ICU) and hospital. Longitudinal, retrospective study of medical records of 116 adults undergoing cardiac surgery from March 2012 to May 2013. The mean age was 57±14 years, predominantly male and coronary artery bypass grafting surgery (52.6%). The MV time was 15.25(7.66 to 23.68) hours. Associated with longer MV was the age (r=0.5,p<0.001), comorbidities (r=0.344,p<0.001), cardiopulmonary bypass time (r=0.244,p=0.008), duration of continuous sedation (r=0.607,p<0.001), sedative doses (r=0.4, p<0.001), time of vasoconstrictors and vasodilators (r=0.711, p< 0.001, r=0.368, p<0.001), drainage of the 1st time (r=0.201, p<0.031), presence of drains (r=0.445, p<0.001), postoperative complications (r=0.524, p< 0.001) and hospital stay. Our data confirms that both preoperative, transoperative and postoperative variables prolong the VM and therefore the hospital stay.