Abstract Background Platelet dysfunction is recognized as an important component of trauma‐induced coagulopathy. However, both its trajectory and its relationship with specific injury patterns remain incompletely understood. Methods This retrospective study included severely injured patients who underwent Multiplate™ impedance aggregometry from emergency room (ER) admission through day 5 in the intensive care unit (ICU). Patients were stratified into isolated traumatic brain injury (TBI), major trauma without TBI (MT), and major trauma with TBI (TBI + MT). To eliminate the influence of platelet count on platelet function testing, platelet numbers were normalized to 250 G/L. Results Seventy‐four patients were included (15 TBI, 28 MT, 31 TBI + MT). Platelet counts declined significantly over 5 days ( p < 0.0001). Unadjusted platelet function (ASPI, ADP, TRAP) was significantly reduced on all days compared with ER admission (all p < .0001). After adjustment for platelet count, only ASPI and ADP remained reduced, and only on day 1. Unadjusted injury‐pattern differences were observed solely on day 1: ASPI and ADP were higher in TBI than MT (both p < .05), and TRAP was highest in TBI compared with MT and TBI + MT ( p < .05). After platelet‐count adjustment, all differences resolved except for ASPI on day 1 ( p < .05). Conclusions Platelet function declined markedly within the first 24 h after trauma, independent of platelet count, indicating an early qualitative dysfunction in addition to thrombocytopenia. Beyond this early phase, no further changes were observed in survivors during the one‐week observation period. We found no consistent association between injury patterns, including TBI, and sustained dysfunction.
Grassegger et al. (Wed,) studied this question.