Preoperative Mild Cognitive Dysfunction Predicts Pulmonary Complications After Coronary Artery Bypass Graft Surgery

Objectives: In elderly patients with mild cognitive impairment, noncompliance with respiratory exercises, ineffective expectoration, reluctance in mobilization, and difficulty in learning the use of drugs such as inhalers were observed in the early postoperative period after coronary artery bypass graft surgery. It was hypothesized that respiratory complications may be more frequent in these patients, and so the postoperative respiratory complications in patients with preoperative mild cognitive impairment were compared with the postoperative respiratory complications of a control group. Design: A prospective cohort control. Setting: A university hospital. Participants: Patients undergoing elective coronary artery bypass graft surgery. Interventions: Investigators separated 48 patients >70 years old who were scheduled for elective coronary artery bypass graft surgery into two groups: patients with preoperative mild cognitive impairment (group A, n = 25) and patients with no cognitive impairment (control group; group B, n = 23). The patients' cognitive status was evaluated preoperatively by the Montreal Cognitive Assessment test. Measurements and Main Results: Pulmonary functions and respiratory complications were evaluated via chest x-rays and spirometry tests preoperatively and postoperatively. A significant difference was observed between the groups, particularly with regard to atelectasis and prolonged ventilation (p < 0.001 and p < 0.05). No significant impairment was observed in the spirometry tests of the control group. However, a significant deterioration was observed in the postoperative spirometry tests of patients with preoperative mild cognitive impairment. Conclusions: This study suggested that mild cognitive impairment was associated with pulmonary complications after coronary artery bypass graft surgery. (C) 2013 Elsevier Inc. All rights reserved.