Effect of postoperative epidural analgesia on morbidity and mortality following surgery in Medicare patients

Background: Because of the uncertainty and limitations in available randomized controlled trials, we performed an analysis of the Medicare claims database to determine whether an association exists between postoperative epidural analgesia and mortality. Methods: A 5% nationally random sample of Medicare beneficiaries from 1997 to 2001 was analyzed to identify patients undergoing segmental excision of the lung (International Statistical Classification of Diseases, Ninth Revision, Clinical Modification codes 32.3 and 32.4), complete pneumonectomy (code 32.5), partial excision of large intestine (codes 45.73 and 45.76), anastomosis of the esophagus (codes 42.5 and 42.6), total knee replacement/ revision (codes 81.54 and 81.55), total/radical abdominal hysterectomy (codes 68.4 and 68.6), partial/radical pancreaticoduodenectomy (codes 52.5 and 52.7), partial/complete nephrectomy (codes 55.4 and 55.5), partial/ complete cystectomy (codes 57.6 and 57.7), hepatotomy/lobectomy of the liver (codes 50.0 and 50.3), partial/total gastrectomy (codes 43.5 to 43.9), and radical retropubic prostatectomy (codes 60.4 and 60.5). Patients were divided into 2 groups, depending on the presence or absence of postoperative epidural analgesia. The rate of major morbidity and death at 7 and 30 days after surgery were compared. Multivariate regression analyses incorporating race, gender, age, comorbidities, hospital size, hospital teaching status, and hospital technology status were performed. Results: The presence of epidural analgesia was associated with a significantly lower odds of death at 7 days (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.38 to 0.73; P =.0001) and 30 days (OR, 0.74; 95% CI, 0.63 to 0.89; P =.0005) after surgery; however, no difference was seen between the groups with regard to overall major morbidity, with the exception of an increase in pneumonia at 30 days for the epidural group (OR, 1.91;[95% CI, 1.09 to 3.34; P =.02). Conclusions: Postoperative epidural analgesia may contribute to lower odds of death after surgery.