OP-34: Clinical validation survey for blood loss quantification in forensic practice

Background and Aims. Blood loss evaluation in forensic medicine is of major relevance for survival time estimation and assessment of the degree of a life-threatening condition. Several algorithms for perioperative blood loss quantification have been proposed in the literature. Specific algorithm,.based on sex, height, weight, distant hemoglobin levels and transfusions, was selected. The aim of this study was to evaluate the power of this algorithm for forensic purposes. Materials and Methods. A clinical prospective study was conducted on 30 consecutive patients during open abdominal aortic surgery. Hemoglobin level was registered at different time points: before, during and after. procedure. lntraoperative blood loss was measured by the surgeon and any transfusion (red blood cells and intraoperative autologous blood transfusion) was recorded. Estimated blood loss was calculated according to the algorithm and results were compared to measured intraoperative blood loss. Results. Mean measured hemorrhage was 1008 ml per patient (min 120, max 2280, SD 714). Significant positive correlation was observed between measured and calculated results I (r=0.647, r=0.701, r=0.768; p<0.01). The algorithm globally overestimated the losses, showing significant difference between the results. Conclusions. Measured hemorrhage was probably underestimated considering hidden blood loss. Nevertheless, caution is mandatory for application of this algorithm in forensic practice.