Effect of coagulation factor concentrate administration on ROTEM® parameters in major trauma.

BACKGROUND: Purified coagulation factor concentrates, such as fibrinogen concentrate (FC) and prothrombin complex concentrate (PCC) are increasingly used as haemostatic therapy for trauma-induced coagulopathy (TIC). The impact of FC and PCC administration on ROTEM parameters among patients with TIC has not been adequately investigated. METHODS: In this retrospective observational study, changes to ROTEM parameters, induced by three different therapeutic interventions, were investigated: patients receiving FC only (FC-group); patients treated with FC and PCC (FC + PCC-group) and patients treated with PCC only (PCC-group). RESULTS: The study population comprised 96 patients who were predominately male (69 [71.9 %]), median age was 45.0 (26.3-60.0) years, and the median injury severity score was 34.0 (25.0-44.5). Administration of FC resulted in a significant reduction of the clotting time (CT) in both the EXTEM and FIBTEM assays but had no effect on INTEM CT. Clot amplitude (CA) increased significantly in the FIBTEM assay but remained unchanged in the EXTEM and INTEM assays. The combined administration of FC and PCC increased FIBTEM maximum clot firmness (MCF) and normalized EXTEM CT but did not change either INTEM or FIBTEM CT. Following PCC therapy, EXTEM and FIBTEM CT normalized; CA at 10 min after CT measurements decreased significantly in EXTEM, INTEM and FIBTEM. CONCLUSIONS: Administration of FC alone or in combination with PCC resulted in a significant improvement of fibrin polymerisation as measured by an increase in FIBTEM MCF. CT is dependent not only on thrombin generation but also on the availability of substrate (fibrinogen). Accelerated fibrin polymerisation rate results in earlier clot formation and consequently shorter CT. PCC administration normalised EXTEM CT below the upper threshold of 80 s. This study was performed at the AUVA Trauma Centre Salzburg, Salzburg, Austria.

Hyperfibrinolysis after major trauma: differential diagnosis of lysis patterns and prognostic value of thrombelastometry.

BACKGROUND: The aim of this study was to diagnose hyperfibrinolysis (HF) and its pattern using thrombelastometry and to correlate the diagnosis with mortality. Furthermore, routine laboratory based and the rotational thrombelastometry analyzer (ROTEM)-derived variables were also correlated with survival. METHODS: Severe trauma patients showing HF in ROTEM were consecutively enrolled in the study. Three different HF patterns were compared: fulminant breakdown within 30 minutes, intermediate HF of 30 to 60 minutes, and late HF after 60 minutes. Injury severity score (ISS), hemodynamics, hemoglobin, hematocrit, platelet count (PC), fibrinogen, and ROTEM variables at admission were analyzed. The observed mortality was compared with the predicted trauma and injury severity score mortality. RESULTS: Thirty-three patients were diagnosed with HF. The mean ISS was 47 +/- 14. Fulminant, intermediate, or late HF (n = 11 each group) resulted in 100%, 91%, or 73% mortality, respectively, with the best prognosis for late HF (p = 0.0031). The actual overall mortality of HF (88%) exceeded the predicted trauma and injury severity score mortality (70%) (p = 0.039). Lower PC (123 +/- 53 vs. 193 +/- 91; p = 0.034), ROTEM prolonged clot formation time [CFT, 359 (140/632) vs. 82 (14/190); p = 0.042], and lower platelet contribution to maximum clot firmness [MCF(EXTEM) - MCF(FIBTEM), 34 (20/40) vs. 46 (40/53); p = 0.026] were associated with increased mortality. CONCLUSION: ROTEM-based diagnosis of HF predicted outcome. Further independent predictors of death were combination of HF with hemorrhagic shock, low PC, and prolonged CFT in ROTEM. ROTEM-based point of care testing in the emergency room is thus able to identify prognostic factors such as prolonged CFT and low platelet contribution to clot firmness (MCF(EX) - MCF(FIB)) earlier than standard laboratory-based monitoring.

Macro- and microcirculatory assessment of cold sensitivity after traumatic finger amputation and microsurgical replantation.

INTRODUCTION: Finger replantations after traumatic amputation are associated with good prognosis and acceptable functional results. However, cold sensitivity is a common and sometimes disabling sequelae after digital replantation. The exact causes of cold intolerance are still unclear; neural as well as vascular mechanisms have been discussed. We examined the macro- and microvascular performance of replanted fingers using high-resolution color-coded sonography for the assessment of skin vessel density of the fingertips as well as nailfold capillary microscopy and laser Doppler anemometry. Subsequently, we correlated these findings with the presence of cold sensitivity of the replanted digits. PATIENTS AND METHODS: Thirty-seven patients (mean age 45 years; range 19-72) with 40 traumatic finger amputations and microsurgical replantations were studied. The mean time interval between amputation and examination was 57.7 months (range 13-95). Macro- and microvascular examination consisted of electronic oscillograms of both arms, photoplethysmograms of all fingers before and after cold test, duplex ultrasound of the finger arteries, high-resolution color-coded sonography of the fingertips and nailfold capillary microscopy with laser Doppler anemometry. RESULTS: Cold sensitivity was present in 33 (83%) of the 40 replanted fingers. Peripheral arterial disease of the upper extremity could be excluded as all oscillograms showed normal findings. A vasospastic reaction after cold test was documented in 74% (30 of 38) of the replanted fingers, compared to 24% (9 of 38) of the contralateral uninjured fingers. Raynaud's phenomenon was restricted to replanted fingers and occurred in 10 of 40 patients (25%). Compared with the contralateral fingertips, reduced skin vessel density was found in 27 of 36 (75%) replants. Nailfold capillary microscopy revealed uncharacteristic morphologic patterns. The capillary flow velocity was 0.28 +/- 0.12 mm/s in the replanted fingers and 0.48 +/- 0.23 mm/s in their unaffected counterparts (P < 0.001). Correlating these findings with the presence of cold intolerance, reduced skin vessel density in the fingertips was significantly different between cold-sensitive replants and those without cold sensitivity (P = 0.05). Reduced skin vessel density was not related to the extent of reconstruction of nerves (P = n.s.), arteries (P = n.s.) and veins (P = n.s.). CONCLUSIONS: Our results do not confirm hypotheses that cold sensitivity after finger replantations is caused by macrovascular problems nor do they support assumptions of a primary capillary microcirculatory failure. Our findings of reduced vessel density point towards diminished thermoregulatory capacities in the fingertips of cold-sensitive replanted digits.