[Perioperative blood coagulation problems in children].

During childhood preoperative coagulation diagnosis is performed to prove or to rule out an inborn coagulation disorder or an acquired von Willebrand disease. The coagulation system of the newborn differs considerably from that of the adults as well as the time in which the single parameters reach adult values. Reducing the coagulation screening to the determination of aPTT and Quick test neglects severe hemostaseological disorders easily, such as von Willebrand disease which is often observed in childhood and often combined with normal aPTT values. Sometimes children affected with hypertrophy of the adenoids have temporary aPTT prolongations combined with normal values for the other coagulation parameters possibly due to lupus inhibitors. When children with deficiencies of coagulation factors need high doses of coagulation concentrates, the number of laboratory controls may be reduced by determination of recovery and the half-life period some time before.