The assessment of pain and plasma beta-endorphin immunoactivity in burned children

The need for better analgesia during burn dressing changes (BDCs) in acutely burned children led us to assess pain during BDC with a large 0-10 thermometer-like scale which was well accepted and appeared to reflect the varying degrees of pain that patients experienced. Pain scores were obtained at least once each minute throughout 33 BDCs in 15 patients of 8-17 years. Plasma levels of beta-endorphin immunoactivity (iB-EP) were measured at 5 intervals before and after BDC; mean values (+/- S.E.M.) ranged from 30.5 +/- 4.63 pg/ml (before BDC and analgesic) to 19.2 +/- 3.02 pg/ml (immediately following BDC). The mean pain score (MPS) for each BDC was inversely related to the iB-EP levels of that day (P less than 0.001 with 4 of the 5 iB-EP determinations). The MPS varied directly with the extent of burn injury and inversely with weight; the 2 variables together predicted MPS as well as the iB-EP alone (r2 = 43 and 36% respectively).