Factors Influence the Effectiveness of Epidural Analgesia after Abdominal Surgery in the Post Anesthetic Care Unit
Abstract
Abstract
Rationale and background: Previous reports have shown that epidural analgesia provided better postoperative analgesia than intravenous opioid. However, data from Department of Anesthesiology, Facutly of Medicine, Khon Kaen University from January to August 2003 has shown different result. In our Post Anesthetic Care Unit (PACU), patients received epidural analgesia for postoperative pain control still had severe pain compared to patients received intravenous opioid (32.6% vs. 38.1%). We would like to investigate the outcome of epidural analgesia and factors associated with it.
Objective : To evaluate and to identify the factors that contribute to the outcomes of epidural analgesia in the PACU after abdominal surgery.
Design: Cross sectional study
Subject: From October 2003 to June 2004, patients aged more than 11 years undergoing abdominal surgery and receiving epidural anesthesia for postoperative pain control were enrolled.
Method: We prospectively collected characteristic data of epidural anesthesia (such as level of block, experience of performer, depth of epidural catheter in epidural space), characteristic data of surgical procedure (such as type of incision and operative time), characteristic data of intraoperative analgesic drugs both intravenous and epidural route (type and doses), data of gender, age, height, body weight, including highest pain scores at the PACU using verbal numeric rating scale 0-10. Pain score < 5 was considered as no significant pain whereas pain score ³ 5 was considered as moderate to severe pain. Data were analyzed using c2 and Student’s t-test. P < 0.05 was considered as statistically significant.
Results: 167 patients were enrolled. Of those, 76 cases had pain score < 5 (45.5%). The factors that contributed to good analgesic outcome were younger age (p = 0.04), female gender (p = 0.01), less height (p = 0.01), higher amount of intraoperative fentanyl (p = 0.04) and shorter time between the last injection of combined local anesthetic drug with opioid via epidural catheter and end of surgery (p = 0.001)
Conclusion: Postoperative pain control using epidural analgesia was satisfactory in 45.5% of the patients in PACU. Preventable factors contributed to the good analgesic outcome are higher amount of intraoperative fentanyl and shorter time between the last injection of combined local anesthetic drug with opioid via epidural catheter at the end of surgery.
