Serum endorphin levels in injured children

Plasma beta-endorphin levels (PBEL) are known to be elevated in acutely injured adults, but this has not been studied in pediatric patients with trauma. We measured PBEL in 46 children who sustained blunt injury. The mean acute PBEL was significantly elevated compared with the mean convalescent PBEL (40.5 +/- 29.0 versus 5.4 +/- 2.1 picomoles per liter, p less than 0.05). PBEL were highest in patients with multiple injuries (60.5 +/- 33.2 picomoles per liter, n = 16). PBEL were also elevated with isolated injuries of the head, face or limbs, and even with less severe injuries, namely multiple abrasions. PBEL were low in patients with abdominal (two patients) or spinal (two patients) injuries. Convalescent PBEL were consistently low. Severely injured patients (Injury Severity Score [ISS] of more than ten) had significantly elevated PBEL compared with patients with minor injuries (ISS less than 10), but some children with low ISS had elevated PBEL. The presence of head injury did not influence PBEL and there was no correlation between PBEL and systolic blood pressure. We have demonstrated that the PBEL is elevated in pediatric patients with trauma.