Sequential systemic platelet‐activating factor and interleukin 8 primes neutrophils in patients with trauma at risk of multiple organ failure

Plasma from 33 patients at risk of multiple organ failure (MOF) after major trauma was tested for a priming effect on neutrophils, and for the presence of platelet-activating factor (PAF) activity and interleukin (IL) 8. Plasma sampled at 3, 6, 12 and 24h after injury significantly primed normal neutrophils to release mean(s.e.m.) 1.26(0.19), 1.33(0.26), 1.04(0.14) and 0.86(0.13)nmol superoxide per min per 1.3 x 10 6 neutrophils respectively (P< 0.05). Priming at 3h after injury was inhibited by mean(s.e.m.) 63.8(7.0) per cent by the PAF antagonist, WEB 2170 (P< 0.01). Mean(s.e.m.) plasma IL-8 was raised at 6 and 12 h after injury to 785(183) and 836(175) pg/ml (P<0.01). At 12h after injury the plasma IL-8 level correlated directly with the number of units of red blood cells transfused (r= 0.64, P<0.01), and was significantly higher in the group of six patients who developed MOF (P<0.05). These data suggest that after trauma the mediators PAF and IL-8 appear sequentially in the circulation, are potential mechanisms of circulating neutrophil priming, and that IL-8 may also be an early biochemical marker predicting the onset of MOF.