Incidence of spinal epidural abscess after epidural analgesia: a national 1-year survey.

EPIDURAL analgesia is most often used for postoperative pain relief, whereas it is no longer so commonly used for long-term treatment of pain from malignant diseases. For perioperative use, the epidural catheter is most frequently inserted before induction of anesthesia while the patient is awake, although there has recently been some debate as to whether regional techniques should or should not be performed during general anesthesia. Side effects of epidural analgesia are common, but the majority are innocuous and well known to anesthesiologists. However, two serious complications of epidural analgesia may result in severe morbidity: the spinal epidural hematoma and the spinal epidural abscess. In a recent editorial, the incidence of spinal epidural hematoma after epidural analgesia in association with the use of low-molecular-weight heparin was estimated to vary from 1:1,000 to 1:10,000 epidural procedures, which is much higher than previously thought. The incidence of spinal epidural abscess after epidural analgesia remains unknown but has been reported to vary widely. No cases of epidural abscess were found in a large Swedish study of 9,232 epidural procedures, whereas there were two cases of abscess formation among 13,000 epidural procedures in a German report, and 3% of the patients in a smaller North American study developed epidural abscess after long-term epidural treatment of chronic pain. The incidence has also been reported to vary from 0.6 to 0.77 per 1,000 catheter days. The present study was undertaken to estimate the incidence of epidural abscess after epidural analgesia in Denmark during a 1-yr period and to evaluate the overall use of epidural analgesia during the same period. We further wished to analyze the treatment and outcome in patients with spinal epidural abscess.