[Continuous epidural analgesia: analysis of efficacy, side effects and risk factors.]

Epidural analgesia with local anesthetics and opioids has a reputation of high efficacy with low incidence of side effects. This study aimed at determining incidence, type and severity of postoperative complications related to epidural analgesia and catheter insertion.

Participated in this retrospective study 469 patients submitted to postoperative epidural analgesia in the period 10/18/99 to 10/18/01. Epidural analgesia was induced with 0.1% bupivacaine and fentanyl (1 to 5 microg.mL-1), at a 3 mL.h-1 rate. Infusion rate was adjusted according to patients' pain complaint. The following variables were evaluated: epidural infusion duration; incidence of side-effects and complications related to demographics, type of surgery and epidural catheter position; and quality of analgesia by means of a pain visual analog scale and a patients' satisfaction index.

Epidural catheters remained in place 2.2 days in average, varying from 6 to 10 days. Global rate of technique-related complications was 46.3%, most of them minor complications without clinical repercussion. From these, 13.9% were directly related to the epidural catheter (disconnection, externalization, low back pain, inflammation and local infection). Other common complications were vomiting and urinary retention. Postoperative analgesia was effective in 97.2% of the patients which referred satisfaction with the technique. Patients without pain or slight pain during the first, second and third postoperative day represented 80.1%, 92.8% and 93.3%, respectively, of the studied population.

Continuous epidural analgesia is effective and safe. Complications were not severe. However, strict vigilance is mandatory to achieve satisfactory analgesia and a low incidence of complications.