C. K. Yang1, A. Teng1, D. Y. Lee1, K. Rose1 1Mount Sinai St. Luke’s Roosevelt Hospital Center,New York, NY, USA
Introduction: Pneumonia after major abdominal surgery (MAS) is common and carries a high potential for increased morbidity and mortality. Additionally, it represents a major burden to the health care system. This study was conducted to define the risk factors associated with pneumonia after MAS.
Methods: The American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database from 2005 to 2012 was queried for patients who underwent MAS using Current Procedural Terminology (CPT) codes. These operations include elective operations performed on the esophagus, stomach, small intestine, large intestine, pancreas and liver. Patients who developed pneumonia after MAS were compared to those who did not. Appropriate statistical tests were used to compare the preoperative characteristics of the two groups. A logistic regression analysis was performed to determine predictors of post-MAS pneumonia.
Results: 165,196 patients who underwent MAS were identified. The overall rate of pneumonia in this cohort was 3.2%. The rate of pneumonia in the esophageal group was the highest at 16.2% which was more than double that of the second highest group, stomach, at 6.4%. Rates of pneumonia for pancreatic, small intestine, liver and large intestine procedure groups were 4.8%, 4.2%, 3.3%, and 2.4% respectively. The median time to the diagnosis of pneumonia was 5 days for all operation types except pancreas which was 6 days. (Table 1) Patients who developed PNA were significantly older, had higher ASA class, and had more co-morbidities compared to those who did not. On multivariate analysis, esophageal surgery was associated with the highest risk of developing post-MAS pneumonia (OR 5.2, 95% CI (4.6-5.9), p < 0.0001), followed by ASA class VI (OR 4.7, 95% CI (3.2-6.8), p <0.0001). Other factors independently associated with the occurrence of PNA include advanced age, male sex, transfer from inpatient or chronic care facility, history of dyspnea, COPD, smoking status, wound classification, and prolonged operative time. Of note, BMI >21 appeared to be associated with less post-MAS PNA (OR 0.7, 95% CI 0.7-0.8, p <0.0001).
Conclusion: Pneumonia following abdominal procedures is associated with a number of variables. Esophageal operations and ASA class were the strongest predictors. These results provide a framework for identifying patients at risk for developing pneumonia post-MAS.
