Risk Factors for Postoperative Pulmonary Complications in Cardiac Surgery Patients: A Single-Center Retrospective Study

Objective: To determine the incidence and structure of postoperative pulmonary complications (PPCs) and to identify independent risk factors for their development in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB).

Materials and Methods: A retrospective single-center study included 658 patients who underwent cardiac surgery in 2024. Demographic, anamnestic, intra- and postoperative data were analyzed. Univariate and multivariate logistic regression analyses were used to identify risk factors for postoperative complications.

Results: PPCs were observed in 71 (10.8%) patients. Atelectasis was the most common complication (7.9%). The incidence of PPCs among smokers was 24.5% (compared to 4.1% among non-smokers), and among obese patients – 21.8% (compared to 6.3% in patients with BMI <30). Multivariate analysis revealed an independent association with the development of PPCs for age >65 years (OR 6.14; 95% CI 3.38–11.16), CPB duration >120 min (OR 5.86; 95% CI 3.57–9.60), smoking history (OR 5.92; 95% CI 2.89– 12.15), obesity (BMI ≥30 kg/m²; OR 5.12; 95% CI 2.70–9.81), and combined surgery (OR 4.69; 95% CI 2.46–8.94). The presence of chronic obstructive pulmonary disease (OR 1.94; 95% CI 1.11–3.39) and pulmonary hypertension (OR 2,14; 95% CI 1.79–5.52) was also associated with an increased risk (all p < 0.001).

Conclusions: The identified modifiable risk factors (smoking, obesity) highlight the importance of preoperative optimization. Nonmodifiable factors (age, type of surgery) define a high-risk group requiring increased attention and early prevention of PPC. The findings may contribute to the development of risk stratification algorithms in cardiac surgery practice.

1. Writing Committee, Bass TA, Abbott JD, et al. 2023 ACC/ AHA/SCAI Advanced Training Statement on Interventional Cardiology (Coronary, Peripheral Vascular, and Structural Heart Interventions): A Report of the ACC Competency Management Committee. J Am Coll Cardiol. 2023;81(14):1386-1438. PMID: 36801119. https://doi.org/10.1016/j.jacc.2022.11.002

2. Ben-David EI, Blumenfeld O, Shapira-Daniels A, Shapira OM. Validation of the society of thoracic surgeons predicted risk of mortality score for long-term survival after cardiac surgery in Israel. J Cardiothorac Surg. 2022;17(1):68. PMID: 35382843. PMCID: PMC8985317. https://doi.org/10.1186/s13019-022-01809-7

3. Grant MC, Crisafi C, Alvarez A, et al. Perioperative Care in Cardiac Surgery: A Joint Consensus Statement by the Enhanced Recovery After Surgery (ERAS) Cardiac Society, ERAS International Society, and The Society of Thoracic Surgeons (STS). Ann Thorac Surg. 2024;117(4):669-689. PMID: 38284956. https://doi.org/10.1016/j.athoracsur.2023.12.006

4. Miskovic A, Lumb AB. Postoperative pulmonary complications. Br J Anaesth. 2017;118(3):317-334. PMID: 28186222. https://doi.org/10.1093/bja/aex002

5. Wang D, Huang X, Wang H, et al. Risk factors for postoperative pneumonia after cardiac surgery: a prediction model. J Thorac Dis. 2021;13(4):2351-2362. PMID: 34012584. PMCID: PMC8107540. https://doi.org/10.21037/jtd-20-3586

6. Fischer MO, Brotons F, Briant AR, et al. Postoperative Pulmonary Complications After Cardiac Surgery: The VENICE International Cohort Study. J Cardiothorac Vasc Anesth. 2022;36(8 Pt A):2344- 2351. PMID: 35094928. https://doi.org/10.1053/j.jvca.2021.12.024

7. Warren OJ, Smith AJ, Alexiou C, et al. The inflammatory response to cardiopulmonary bypass: part 1--mechanisms of pathogenesis. J Cardiothorac Vasc Anesth. 2009;23(2):223-231. PMID: 18930659. https://doi.org/10.1053/j.jvca.2008.08.007

8. Lee SW, Lee S, Hahm KD. Postoperative Pulmonary Complications after Transcatheter Aortic Valve Implantation under Monitored Anesthesia Care versus General Anesthesia: Retrospective Analysis at a Single Large Volume Center. J Clin Med. 2021;10(22):5365. PMID: 34830646. PMCID: PMC8618621. https://doi.org/10.3390/jcm10225365

9. Krichevsky LA, Rybakov VYu, Dvoryadkin AA, Protsenko DN. Systemic inflammatory response in cardiac surgery. Russian Journal of Anesthesiology and Reanimatology. 2021;(3):94‑102. (In Russ.). https://doi.org/10.17116/anaesthesiology202103194

10. Esper SA, Subramaniam K, Tanaka KA. Pathophysiology of Cardiopulmonary Bypass: Current Strategies for the Prevention and Treatment of Anemia, Coagulopathy, and Organ Dysfunction. Semin Cardiothorac Vasc Anesth. 2014;18(2):161-176. PMID: 24876231. https://doi.org/10.1177/1089253214532375

11. Eremenko AA, Zyulyaeva TP. Postoperative acute respiratory failure in cardiac surgery. Khirurgiia (Mosk). 2019;(8):5-11. PMID: 31464267. https://doi.org/10.17116/hirurgia20190815

12. Wang Y, Luo Z, Huang W, Zhang X, Guo Y, Yu P. Comparison of Tools for Postoperative Pulmonary Complications After Cardiac Surgery. J Cardiothorac Vasc Anesth. 2023;37(8):1442-1448. PMID: 37120322. https://doi.org/10.1053/j.jvca.2023.03.031

13. Setlers K, Jurcenko A, Arklina B, et al. Identifying Early Risk Factors for Postoperative Pulmonary Complications in Cardiac Surgery Patients. Medicina (Kaunas). 2024;60(9):1398. PMID: 39336439. PMCID: PMC11433804. https://doi.org/10.3390/medicina60091398

14. D’Agostino RS, Jacobs JP, Badhwar V, et al. The Society of Thoracic Surgeons Adult Cardiac Surgery Database: 2018 Update on Outcomes and Quality. Ann Thorac Surg. 2018;105(1):15-23. PMID: 29233331. https://doi.org/10.1016/j.athoracsur.2017.10.035

15. Zozulya MV, LenkinAI, SotnikovAV, Kurapeev IS, Saiganov SA, Lebedinskii KM. Intraoperative and early postoperative respiratory function in patients with coronary artery disease undergoing on-pump or off-pump coronary artery bypass surgery. Russian Journal of Anesthesiology and Reanimatology. 2020;(4):54‑60. (In Russ.). https://doi. org/10.17116/anaesthesiology202004154

16. Kuzkov VV, Suborov EV, Fot EV, Rodionova LN, Sokolova MM, Lebedinskiy KM, Kirov MYu. Postoperative pulmonary complications and acute respiratory distress syndrome – better prevent then treat. Russian Journal of Anesthesiology and Reanimatology. 2016;61(6):461-468. (In Russ.). https://doi. org/10.18821/0201-7563-2016-6-461-468

17. Abbott TEF, Fowler AJ, Pelosi P, et al. A systematic review and consensus definitions for standardised end-points in perioperative medicine: pulmonary complications. Br J Anaesth. 2018;120(5):1066-1079. PMID: 29661384. https://doi.org/10.1016/j.bja.2018.02.007

18. Baris O, Onyilmaz TA, Kaya H. Frequency and Predictors of Pneumonia After Isolated Coronary Artery Bypass Grafting (CABG): A Single-Center Study. Diagnostics (Basel). 2025;15(2):195. PMID: 39857079. PMCID: PMC11763973. https://doi.org/10.3390/diagnostics15020195

19. Tanner TG, Colvin MO. Pulmonary Complications of Cardiac Surgery. Lung. 2020;198(6):889-896. PMID: 33175990. PMCID: PMC7655908. https://doi.org/10.1007/s00408-020-00405-7

20. Zainab A, Nguyen DT, Graviss EA, Fatima S, Masud FN, MacGillivray TE. Development and Validation of a Risk Score for Respiratory Failure After Cardiac Surgery. Ann Thorac Surg. 2022;113(2):577-584. PMID: 33839130. https://doi.org/10.1016/j.athoracsur.2021.03.082

21. Matthay MA, Arabi Y, Arroliga AC, et al. A New Global Definition of Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med. 2024;209(1):37-47. PMID: 37487152. PMCID: PMC10870872. https://doi.org/10.1164/rccm.202303-0558ws

22. Bautin AE, Kasherininov IYu, Laletin VA, et al. Prevalence and causes of the postoperative acute respiratory failure in cardiac surgery. Annals of Critical Care. 2016;4:19-26. (In Russ.).

23. RongLQ, DiFrancoA, GaudinoM. Acute respiratory distress syndrome after cardiac surgery. J Thorac Dis. 2016;8(10):E1177- E1186. PMID: 27867583. PMCID: PMC5107484. https://doi. org/10.21037/jtd.2016.10.74

24. Wang D, Lu Y, Sun M, et al. Pneumonia After Cardiovascular Surgery: Incidence, Risk Factors and Interventions. Front Cardiovasc Med. 2022;9:911878. PMID: 35845037. PMCID: PMC9280273. https://doi.org/10.3389/fcvm.2022.911878

25. Kermani MS, Dehesh T, Pouradeli S, Esmaili BS. Factors affecting the prolongation of mechanical ventilation in patients after cardiac surgery. J Cardiothorac Surg. 2025;20(1):104. PMID: 39875916. PMCID: PMC11776133. https://doi.org/10.1186/s13019- 024-03247-z

26. Naveed A, Azam H, Murtaza HG, Ahmad RA, Baig MAR. Incidence and risk factors of Pulmonary Complications after Cardiopulmonary bypass. Pak J Med Sci. 2017;33(4):993-996. PMID: 29067080. PMCID: PMC5648979. https://doi.org/10.12669/pjms.334.12846

27. Musallam KM, Rosendaal FR, Zaatari G, et al. Smoking and the risk of mortality and vascular and respiratory events in patients undergoing major surgery. JAMA Surg. 2013;148(8):755-762. PMID: 23784299. https://doi.org/10.1001/jamasurg.2013.2360

28. Jiang X, Xu J, Zhen S, Zhu Y. Obesity is associated with postoperative outcomes in patients undergoing cardiac surgery: a cohort study. BMC Anesthesiol. 2023;23(1):3. PMID: 36600190. PMCID: PMC9811698. https://doi.org/10.1186/s12871-022-01966-1

29. Bazdyrev ED, Polikutina OM, Slepynina YuS, Garganeeva NP, Barbarash OL. Chronic obstructive pulmonary disease as a predictor of unfavourable prognosis in patients after myocardial revascularization. CardioSomatics. 2018;9(4):5–10. https://doi.org/10.26442/22217185.2018.4.000022