Plasma histamine levels in polytraumatized patients.

In a prospective clinical trial, plasma histamine levels were measured in 28 polytrauma patients on day 1, 5 and 14 after trauma. Only those subjects who died were drop-outs. All patients had severe polytrauma with at least 3 body regions involved. The median plasma histamine levels at all three time points were significantly higher than in patients with single trauma of the extremities or before selective orthopaedic surgery but still in the normal range (less than 1 ng/ml). However, all patients with plasma levels above 1 ng/ml on days 1 and 5 died, as did all patients with levels above 0.5 ng/ml on day 1. Thus the elevation of plasma histamine levels, for whatever reason, appears to be a prognostic factor for bad outcome in polytrauma patients.