Alterations of the global haemostatic function test 'resonance thrombography' in spontaneously traumatised dogs

Samples taken from 30 dogs with spontaneously acute trauma were investigated with two different resonance thrombographs (instrument 2: 28 dogs), a global method for examination of the haemostatic system. Reaction time of the resonance thrombogram (RTG-r), fibrin generation time (RTG-f), fibrin amplitude (RTG-F) and parameters of platelet function [amplitude of the platelet leg (RTG-P) and descending time of the platelet leg (RTG-p)] were evaluated statistically and compared with a normal control as well as with the results of individual components of the haemostatic system and other screening tests. Comparison of the results of the RTG of dogs suffering from trauma with the normal control revealed differences only for RTG-r, which was longer when measured with instrument 1 and lower RTG-F values measured with both instruments. Depending on the RTG parameter and instrument, only 1-6 samples showed values outside the reference ranges. Only 4 out of 26 cases (resonance thrombograph 2: 2 out of 24 cases) with mild to moderate deficiency in individual coagulation factor activity showed a prolongation of RTG-r which was significantly less sensitive than activated partial thromboplastin time (p < 0.001). Of the 26 samples having mainly mildly to moderately increased fibrin(ogen) degradation product (FDP) levels (median: 39 microg/ml, range: 2-90 microg/ml, reference values: <18 microg/ml) only between 1 and 5 showed abnormalities of the parameters RTG-f and/or RTG-F. The results of this study show in particular the limited sensitivity of the method for detecting individual coagulation factor deficiencies and minimal to moderate increases of FDP concentrations. Remarkable alterations of fibrin generation as measured by the resonance thrombograph are a rare condition in dogs with acute accidental trauma.