Incidence and risk factors for aspiration pneumonia after cardiovascular surgery in elderly patients

Pneumonia after cardiovascular surgery is the leading cause of mortality. Postoperative aspiration pneumonia becomes a critical issue in the management of cardiovascular surgery in the aging society. The aim of this study was to investigate the incidence and risk factors of aspiration pneumonia after cardiovascular surgery for elderly patients.

This study consisted of 123 elderly patients (>65 years old) who survived their final extubation following cardiovascular surgery at Kinan Hospital. Patients were divided into aspiration pneumonia and no pneumonia groups. Postoperative aspiration pneumonia was diagnosed by two independent physicians according to the nursing- and healthcare-associated pneumonia guidelines by the Japanese Respiratory Society.

Among the patients, 12 (9.8 %) had aspiration pneumonia. There were no differences in patients' characteristics between the groups except for a history of cerebral vascular disorder (aspiration pneumonia 42 % vs no pneumonia 15 %, p = 0.04) and ejection fraction (EF) (aspiration pneumonia 56 ± 21 % vs no pneumonia 66 ± 13 %, p = 0.02). Only six (5 %) patients needed more than 12 h intubation. There was no difference in the operative factors between the groups. Neurological deficit was more frequently observed in the aspiration pneumonia group (33 vs 5 %, p = 0.005). Multivariable logistic regression analysis showed that the history of cerebral vascular disorder and neurological deficit after surgery was independent risk factors for aspiration pneumonia after cardiovascular surgery.

Our results could assist in screening elderly patients who should be more carefully evaluated before oral nutrition to minimize morbidity and mortality after cardiovascular surgery.