Development and Validation of Nomogram Models for Postoperative Pneumonia in Adult Patients Undergoing Elective Cardiac Surgery

Abstract

Background: Postoperative pneumonia (POP) is a frequent complication following cardiac surgery, related to increased morbidity, mortality and healthcare costs. The objectives of this study were to investigate the risk factors associated with POP in adults undergoing elective cardiac surgery and to develop and validate nomogram models.Methods: We conducted a multicenter retrospective study in four cardiac centers in China. Adults operated with elective open-heart surgery from 2016 to 2020 were included. Patients were randomly allocated to training and validation sets by 7:3 ratio. Demographics, comorbidities, laboratory data, surgical factors, and postoperative outcomes were collected and analyzed. Risk factors for POP were identified by univariate and multivariate analysis. Nomograms were constructed based on the multivariate logistic regression models and were evaluated with calibration, discrimination and decision curve analysis.Results: A total of 13,380 patients meeting the criteria were included and POP developed in 882 patients (6.6%). The mortality was 2.0%, but it increased significantly in patients with POP (25.1 vs. 0.4%, P < 0.001). Using preoperative and intraoperative variables, we constructed a full nomogram model based on ten independent risk factors and a preoperative nomogram model based on eight preoperative factors. Both nomograms demonstrated good calibration, discrimination, and were well validated. The decision curves indicated significant clinical usefulness. Finally, four risk intervals were defined for better clinical application.Conclusions: We developed and validated two nomogram models for POP following elective cardiac surgery using preoperative and intraoperative factors, which may be helpful for individualized risk evaluation and prevention decisions.

Prophylactic Penehyclidine Inhalation for Prevention of Postoperative Pulmonary Complications in High-risk Patients: A Double-blind Randomized Trial

“…Respiratory infections were the most common postoperative pulmonary complication in our patients, with an incidence of 19.0%, which was well within the reported range in high-risk patients. [41][42][43] This was followed by atelectasis (5.7%), pleural effusion (4.6%), bronchospasm (2.9%), respiratory failure (2.2%), and pneumothorax (0.2%). Most (84%) pulmonary complications occurred within the first 5 days with a median onset on postoperative day 2, as might be expected from the acute effects of surgery and anesthesia.…”

Pneumonia After Cardiovascular Surgery: Incidence, Risk Factors and Interventions

“…Patients with a history of cardiac surgery have a significantly increased risk of postoperative complications such as POP and in-hospital mortality, which has been confirmed in multiple studies (9,19,20,26,38). Compared with patients undergoing primary surgery, patients undergoing redo cardiac surgery tend to have poorer physical fitness and tolerance, more underlying diseases, more complicated anatomy and surgical operations.…”

“…The incidence of POP reported in previous literature varied greatly due to various surgical populations, from 2 to 15% in most of the studies (7,9,19,20). The most frequently reported studies for POP were conducted in patients undergoing surgery for valvular and coronary disease, the incidence of which was mostly between 2.1-8.2% (7,9).…”

“…Advanced age has been widely reported to be associated with the development of POP after cardiovascular surgery (10,19,20,(24)(25)(26). In a prospective multicenter study, Ailawadi et al found that the risk of POP after cardiac surgery increased significantly with age, presenting a dose-effect relationship (27).…”

“…Renal insufficiency and chronic kidney disease have also been reported to be an independent risk factor for POP after cardiac surgery in previous literature (7,19). Kinlin et al found that patients with preoperative creatinine levels >1.2 mg/dL had a 1.6-fold increased risk of POP after CABG (7).…”