Nationwide incidence of serious complications of epidural analgesia in the United States

Background This study aimed to describe the incidence and risk factors of in-hospital spinal hematoma and abscess associated with epidural analgesia in adult obstetric and non-obstetric populations in the United States. Methods The Nationwide Inpatient Sample was analyzed to identify patients receiving epidural analgesia from 1998 to 2010. Primary outcomes were incidence of spinal hematoma and epidural abscess. Use of decompressive laminectomy was also investigated. Regression analyses were conducted to assess predictors of epidural analgesia complications. Differences in mortality and disposition of patients at discharge were compared in patients with and without neuraxial complications. Obstetric and non-obstetric patients were studied separately. Results A total of 3,703,755 epidural analgesia procedures (2,320,950 obstetric and 1,382,805 non-obstetric) were identified. In obstetric patients, the incidence of spinal hematoma was 0.6 per 100,000 epidural catheterizations (95% CI, 0.3 to 1.0 × 10^-5). The incidence of epidural abscess was zero. In non-obstetric patients, the incidence of spinal hematoma and epidural abscess were, respectively, 18.5 per 100,000 (95% CI, 16.3 to 20.9 × 10^-5) and 7.2 per 100,000 (95% CI, 5.8 to 8.7 × 10^-5) catheterizations. Predictors of spinal hematoma included type of surgical procedure (higher in vascular surgery), teaching status of hospital, and comorbidity score. Patients with spinal complications had higher in-hospital mortality (12.2% vs. 1.1%, P < 0.0001) and were significantly less likely to be discharged to home. Conclusions This large nationwide data analysis reveals that the incidence of epidural analgesia-related complications is very low in obstetric population epidural analgesia and much higher in patients having vascular surgery.