Platelet adenosine diphosphate inhibition in trauma patients by thromboelastography correlates with paradoxical increase in platelet dense granule content by flow cytometry.

BACKGROUND: The mechanism of platelet dysfunction in acute traumatic coagulopathy is unknown. Traumatic brain injury is hypothesized as a cause, while some investigators presume platelets become "exhausted." We hypothesized that platelet hyperstimulation and consumption resulting from trauma leads to decreased platelet function secondary to depletion of platelet granules. METHODS: Twenty-five trauma patients were divided into traumatic brain injury and no traumatic brain injury groups. Healthy volunteers served as controls. All had thromboelastography with platelet mapping and flow cytometric assays of mepacrine performed. Mepacrine uptake in unstimulated platelets was used for quantification of platelet content of dense granules. RESULTS: Twelve patients with traumatic brain injury and 13 patients without traumatic brain injury were enrolled. Twenty-one trauma patients showed adenosine diphosphate inhibition (>30%) on thromboelastography with platelet mapping compared with the healthy volunteers who served as controls (P < .01). Mepacrine assay showed a difference in mean fluorescent intensity for all trauma patients of 4,259 ± 1,341 compared with controls of 3,143 ± 709 (P = .044), correlating with greater quantities of dense granules. Neither adenosine diphosphate inhibition nor average difference in mean fluorescent intensity between traumatic brain injury and no traumatic brain injury groups were significant (P = .2). CONCLUSION: Trauma patients maintain their dense granule, contradicting the theory of platelet granule exhaustion as the etiology for platelet dysfunction in traumatic brain injury.

Trauma transfers and definitive imaging: patient benefit but at what cost?

Many patients undergo computed tomography (CT) scan before transfer to definitive care. Despite this, studies are often repeated on arrival to the trauma center. We evaluated a policy to provide formal in-house interpretation of images performed at outside hospitals. A 3-month retrospective analysis was performed. Two groups were compared. Patients in the in-house interpretation (IHI) group underwent in-house interpretation of outside images. Those images not meeting criteria were placed in the comparison group without in-house radiologic interpretation. Demographics, CT scan data, billing and productivity loss, and extrapolated cancer risk reduction were analyzed. There were no significant differences in demographic or injury data. Fewer total CT scans were performed in the IHI group (223 vs. 320, P = 0.04). The IHI group underwent fewer repeated CT scans (25 vs. 62, P = 0.02; odds ratio [OR], 0.53). Fewer patients were exposed to repeat CT scans (17 vs. 32; OR, 0.48). Total hospital billings decreased by $188,285 ($4,592/patient) in the IHI group. Uncaptured work relative value units totaled 152.19 (3.71/patient) in the IHI group. Radiation exposure decreased by 8 per cent. Use of outside hospital imaging as the definitive evaluation of injured patients is safe and results in an overall decrease in radiation exposure and healthcare cost.

Experience with prothrombin complex for the emergent reversal of anticoagulation in rural geriatric trauma patients.

BACKGROUND: Therapeutic anticoagulation in the geriatric trauma population is increasingly common. Fresh frozen plasma, while the criterion standard for correction, has limited availability and associated transfusion risks. We examined our use of prothrombin complex concentrate for immediate reversal of therapeutically anticoagulated geriatric trauma patients. METHODS: This was a 1-year, retrospective review of 25 geriatric trauma patients who received either fresh frozen plasma alone or prothrombin complex concentrate and met the inclusion criteria of age >55 years, current warfarin use, and an admission international normalized ratio of >1.5. Fifteen patients received prothrombin complex concentrate and 10 patients received fresh frozen plasma alone. We examined demographics, laboratory values, and blood product use. RESULTS: The mean ages were similar (77 vs 80 years). Patients had similar mean Injury Severity Score (19.1 vs 19.2). Survivor duration of hospital stay (7.7 vs 9.5; P = .37) and duration of stay in the intensive care unit (4.4 vs 7.1; P = .25) trended positively in the prothrombin complex concentrate group. The prothrombin complex concentrate group received fewer units of fresh frozen plasma (1.6 [range, 0-6] vs 2.7 [range, 2-4]; P = .05), with a greater decrease in international normalized ratio (51% vs 43%; P = .05). Six patients (40%) in the prothrombin complex concentrate group avoided fresh frozen plasma transfusion altogether. CONCLUSION: Prothrombin complex may be used safely and effectively to reverse emergently anticoagulation in geriatric trauma patients.