Adaptive Support Ventilation Reduces the Incidence of Atelectasis in Patients Undergoing Coronary Artery Bypass Grafting: A Randomized Clinical Trial

BACKGROUND Pulmonary complications are common following cardiac surgery and can lead to increased morbidity, mortality, and healthcare costs. Atelectasis is the most common respiratory complication following cardiac surgery. One of the most important methods for reducing pulmonary complications is supportive care with protective ventilation strategies. In this study, we aimed to assess the effect of adaptive support ventilation (ASV) on atelectasis in patients undergoing cardiac surgery. METHODS In this single-blind randomized clinical trial, 115 patients, undergoing coronary artery bypass grafting, were randomly allocated into 2 groups: 57 patients in the intervention and 58 patients in the control group. Patients in the intervention group were weaned with ASV, while patients in the control group were managed using synchronized intermittent mandatory ventilation (SIMV) and pressure support. The incidence of atelectasis, duration of mechanical ventilation, manual ventilator setting, arterial blood gas measurements, and length of hospital stay were compared between the groups. RESULTS The incidence of atelectasis, number of changes in the manual ventilator setting, number of alarms, and length of hospital stay reduced in the intervention group. However, duration of mechanical ventilation and number of ABG measurements were not significantly different between the groups. CONCLUSIONS The ASV mode could reduce the incidence of atelectasis and length of hospital stay. However, it did not reduce the duration of mechanical ventilation. It seems that ASV is not a superior mode for faster extubation.