To determine the level of pain that acutely burned children experience, we obtained pain scores before, during and after burn dressing change (BDC). Pain scores were higher during the BDC, consistent with severe pain during this procedure. A positive correlation between pain scores and the body surface area (BSA) burned suggests that pain increases with the size of the burn. Contrary to widely held beliefs, comparison of mean pain scores and the percent of 3rd degree burn revealed that the larger the area of full-thickness injury, the greater the pain. Regardless of wide variations in patient characteristics, fixed doses of oral narcotics were usually prescribed for pain. Patients with BSA greater than 70% experienced severe pain during BDC despite the type, dose or route of opioids. These findings suggest the need for (a) education to correct the myth that 'third-degree burns don't hurt'; (b) revision of analgesic prescribing patterns in the burned child; and (c) research to determine the mechanisms (e.g., tolerance or deafferentation) underlying the opioid-resistant nature of pain after large burns.

No abstract

A novel bivalent opioid tetrapeptide, biphalin (Tyr-D-Ala-Gly-Phe-NH)2, was synthesized based on structure-activity relationships. The analgesic activity of biphalin was assessed in comparison to morphine in rats. Drugs were administered subcutaneously (s.c.), intravenously (i.v.) and intrathecally (i.t.). Tail flick and tail pinch were used as tests for analgesia. Biphalin s.c. showed negligible analgesic activity, but when given i.v. produced significant analgesia, although less potent than morphine via this route. In contrast, intrathecal biphalin was more potent than morphine. These results indicate that biphalin has intrinsic activity that is compromised by enzymatic degradation or redistribution in the periphery, properties that may render it useful in exploring analgesic actions of locally applied opioids in the periphery without the likelihood of unwanted central effects.