title: [Heparin level determination during extracorporeal circulation in open heart surgery].
abstract: Because of the high dosages which have to be given during extracorporal circulation it is often impossible to measure the end point of coagulation for both thrombin time and aPTT. A correct determination of the heparin level has become possible with synthetic substrates with the help of the "Protopath proteolytic enzyme detection system" (AHS, Munich). With a fluorogenic synthetic substrate in a one-way cuvette and calibrated fluorometer the heparin and AT III levels can easily be measured. Very high levels of heparin which averaged 6,9 U/ml +/- 1,0 10 minutes after heparinization and 4,4 U/ml +/- 1,0 60 minutes later were found in ten patients with open heart surgery during extracorporal circulation. AT III decreased to less than 50% possibly due to dilutional effects. Ten minutes after protamine neutralization heparin levels were less than 0,1 U/ml. After two hours AT III levels returned to 70%. Measurement of heparin blood levels adds to the quality of anticoagulant control in situations where high dosages of heparin are given.
mesh_terms: D000328:Adult; D000990:Antithrombin III / Q000378:metabolism; D006348:Cardiac Surgical Procedures; D003327:Coronary Disease / Q000097:blood / Q000601:surgery; D005112:Extracorporeal Circulation; D005470:Fluorometry / Q000379:methods; D006349:Heart Valve Diseases / Q000097:blood / Q000601:surgery; D006493:Heparin / Q000097:blood*; D006801:Humans; D008875:Middle Aged; D010314:Partial Thromboplastin Time; D011479:Protamines / Q000008:administration & dosage; D013918:Thrombin Time
chemical_list: D011479:Protamines; D000990:Antithrombin III; D006493:Heparin
vernacular_title: Heparin-Spiegel-Bestimmung während exkorporalem Kreislauf bei Operationen am offenen Herzen.