An Evaluation of Factors Related to Postoperative Pain Control in Burn Patients

Satisfactory treatment of burn pain continues to be elusive. The perioperative period is particularly challenging. The contributions of acute tolerance and opioid-induced hyperalgesia have not been previously explored in burn patients. As these phenomena have been identified perioperatively in other patient populations, we sought to characterize the burn perioperative period and to determine variables associated with poor postoperative (post-OR) pain control. A retrospective review of 130 adult burn patients who underwent surgical treatment for their burn injuries was performed. Variables collected included: demographics, burn injury data, perioperative self-reported pain scores, and perioperative opioid amounts. Correlations and multiple logistic regressions were used to assess the relationship between these variables and post-OR pain control. Pain increased throughout the perioperative period from 2.64 24 hours prior to the operation (pre-OR) to 3.81 24 hours following the OR (post-OR, P < .0001). Post-OR pain was correlated with pre-OR pain, pre-OR opioid amounts, OR opioid amounts, and post-OR opioid amounts. When the subgroup of patients with controlled pre-OR pain (<3 pain rating) was analyzed, only pre-OR opioids and post-OR opioids remained correlated with worse post-OR pain. While this study is retrospective, there is a suggestion that opioid amounts given pre-OR and intraoperatively are correlated with worse post-OR pain. While an increase in pain ratings postoperatively are anticipated, the additional contributions of acute tolerance and opioid-induced hyperalgesia need to be determined. Pharmacologic intervention directed at these mechanisms can then be administered to achieve better postoperative pain control.