Comparison of Risk Factors Between Mediastinitis and Sternal Dehiscence After Adult Cardiac Surgery

Background: Mediastinitis is a severe complication after cardiac surgery. The aim of this study was to determine the incidence of postoperative mediastinitis, the predictors of mediastinitis, and sternal dehiscence in adult cardiac surgery patients. Methods: In this retrospective study, the records of 60 patients were evaluated regarding mediastinitis and dehiscence after cardiac surgery in a referral cardiovascular hospital in Tehran, Iran. Results: In the present study, 4360 patients underwent surgery over 18 months from September 2017 through March 2019. Of this total, 60 patients with a diagnosis of mediastinitis and sternal dehiscence were included in the study's analysis. In our investigation, 1.03% of the cases (45/4360) had mediastinitis and 0.3% (15/4360) cases experienced sternal dehiscence. Among the many risk factors that were examined, there were significant differences between the mediastinitis and dehiscence groups regarding diabetes mellitus (P =0.007), a history of preoperative chronic kidney disease (P =0.02), a history of myocardial infarction (P =0.002), a history of arrhythmia before cardiac surgery (P =0.02), reoperation due to postoperative bleeding (P =0.07), the number of patients transferred to the ICU with the sternum left open (P <0.001), postoperative pulmonary complications (P =0.007), and postoperative arrhythmias (P =0.04). Conclusions: There were significant differences between the mediastinitis and dehiscence groups regarding diabetes mellitus, a history of preoperative chronic kidney disease, myocardial infarction and arrhythmias before cardiac surgery, reoperation due to postoperative bleeding, the number of patients transferred to the ICU with the sternum left open, postoperative pulmonary complications, and postoperative arrhythmias.