[Preoperative identification of patients with impaired (primary) haemostasis. A practical concept]

The findings of a large prospective study designed to identify primary and/or secondary haemostatic disorders before surgical interventions are presented. A total of 5649 unselected adult patients were enrolled to identify impaired haemostasis before surgical interventions. Each patient was asked to answer a standardized questionnaire concerning bleeding history. Activated partial thromboplastin time (aPTT), prothrombin time (PT), and platelet counts (PC) including PFA-100 (platelet function analyzer): collagen-epinephrine (C/E), and collagen-ADP (C/ADP) were routinely done in all patients. Additional tests, bleeding time (BT), von Willebrand factor (VWF:Ag, VWF:Rcof) and a further haemostaseological diagnostic was performed only in patients with a positive bleeding history and/or evidence of impaired haemostasis; e.g., drug ingestion. The bleeding history was negative in 5021 patients (88.8%) but positive in the remaining 628 (11.2%). Impaired haemostasis could be verified only in 256 (40.8%) of these patients. The vast majority was identified with PFA-100: C/E (n = 250; 97.7%). The sensitivity of the PFA-100: collagen-epinephrine was the highest (90.8%) in comparison to the other screening tests (BT, aPTT, PT, VWF : Ag). The positive predictive value (to detection of impaired haemostasis) of the PFA-100: collagen-epinephrine with the standardized questionnaire was high (82%), but the negative predictive value was higher (93%). The use of a standardized questionnaire and, if indicated, the PFA-100: C/E and/or other specific tests not only ensure the detection of impaired haemostasis in almost every case but also a significant reduction of the costs. Based on these data, national regards are formulated or under construction.