Diaphragmatic elevations following cardiac surgery

Background: This study aims to investigate the incidence, prognosis, and etiology of diaphragmatic elevation following cardiac surgery. Methods: Between February 2019 and December 2019, a total of 888 patients (631 males, 257 females; mean age: 58.4±12.1 years; range, 19 to 84 years) who underwent cardiac surgery were retrospectively analyzed. A series of chest X-rays taken before and after surgery were analyzed to detect diaphragmatic elevation. The patients were divided into two groups: those without diaphragmatic elevation (Group 1, n=789) and those with diaphragmatic elevation (Group 2, n=99). Results: Diaphragmatic elevation occurred in 11.14% of patients. Of these patients, 85% recovered within a year. Patients with concomitant chronic obstructive pulmonary disease and diaphragmatic elevation exhibited prolonged mechanical ventilation compared to chronic obstructive pulmonary disease patients without elevation. The incidence of diaphragmatic elevation was higher in coronary artery bypass grafting patients compared to others (p<0.001). A secondary analysis utilizing propensity score matching revealed topical cold slush as an independent risk factor for diaphragmatic elevation. Incidence and hospitalization duration were higher among patients exposed to topical cold slush (p=0.011 and p=0.002, respectively). Left internal mammary artery harvesting and diabetes mellitus were associated with increased incidence of diaphragmatic elevation. Conclusion: Diaphragmatic elevation is frequent following cardiac surgery, particularly in coronary artery bypass grafting patients with diabetes mellitus. Among chronic obstructive pulmonary disease patients, diaphragmatic elevation can lead to unfavorable clinical outcomes. Minimizing the use of topical cold slush and considering beating heart surgery may be prudent in high-risk groups to reduce diaphragmatic elevation incidence.