Why should we perform pulmonary function test before coronary artery bypass grafting?

Abstract

Objectives: In this study, we aimed to examine the relationship between preoperative pulmonary function test (PFT) parameters and postoperative length of invasive mechanical ventilation (IMV), length of intensive care unit (ICU) and hospital stay in patients who underwent coronary artery bypass grafting (CABG). Patients and methods: Between October 2017 and July 2018, a total of 100 patients (84 males, 16 females; mean age: 61.1±10.0 years; range, 41 to 85 years) who underwent elective CABG surgery for the first time and who did not have any additional cardiac problems, except for coronary artery disease, had an ejection fraction (EF) of ≥30% and underwent preoperative PFTs were retrospectively analyzed. The percent forced vital capacity (FVC %) predicted from the PFT values and percent forced expiratory volume in 1 sec (FEV1%) were recorded. An IMV duration of ≤12 h was considered normal and >12 h was considered prolonged. A length of ICU stay for ≤24 h was considered normal and >24 h was considered prolonged. A length of hospital stay for ≤7 days was considered normal and >7 was considered prolonged. Results: As the predicted FVC (%) value decreased in the preoperative PFTs, the length of IMV, length of ICU and hospital stay increased significantly (p=0.040, p=0.036, p=0.009, respectively). In terms of the predicted FEV1 (%) value, as the predicted FEV1 (%) value decreased, the duration of IMV, length of ICU and hospital stay prolonged (p=0.023, p=0.044, p=0.024, respectively). Conclusion: It is possible to have an idea about postoperative duration of ventilation, ICU and hospital stay based on PFT parameters. Also, the result would be more realistic when adapted to existing scoring systems to assess postoperative complications. Therefore, we believe that scoring systems for evaluating complications after cardiac surgery should include not only chronic lung disease, but also PFT parameters that give a more detailed information.