title: Familial antithrombin-III deficiency during cardiopulmonary bypass: a case report.
abstract: The serine protease inhibitor antithrombin-III (AT-III) is the principal in vivo inhibitor of blood coagulation, inactivating mainly thrombin, but also other serine proteases. Binding of AT-III to heparin dramatically increases its inhibitory effect. AT-III deficiency during cardiopulmonary bypass (CPB) can lead to insufficient anticoagulation which cannot be treated by higher doses of heparin. A 60-year-old male with familial AT-III deficiency was admitted to our hospital for coronary artery bypass surgery and aortic valve replacement. Four days before the operation, acenocoumarol was stopped and anti-Xa nadroparincalcium (Fraxiparine) was started. AT-III activity at that time was 56%. Two hours before the operation, a single dose of 4500 IU AT-III concentrate was administered. Heparinization was performed with 400 IU/kg of porcine mucosal heparin, increasing the activated coagulation time (ACT) from a baseline of 115 to 549 s. AT-III activity at that time was above 100% and the plasma D-dimer concentration was 230 ng/l. ACTs during CPB remained above 999 s, whereas the AT-III activity dropped to 54% and the D-dimer increased up to 500 ng/l at the end of CPB. CPB was terminated uneventfully. Heparin was reversed with 3 mg/kg protamine chloride, decreasing the ACT to 155 s. In the intensive care unit (ICU), the patientreceived prophylactic Fraxiparine and 1500 IU AT-III, increasing the AT-III activity to 84%. Postoperatively, there was continued blood loss, which necessitated the administration of whole blood and eventually re-exploration. The case presented illustrates an uneventful treatment of a patient with a hereditary AT-III deficiency undergoing CPB. In spite of an uneventful treatment with AT-III pre-CPB, administration of prophylactic AT-III concentrate after surgery should be considered with caution, as this might increase the postoperative morbidity.
authors.affiliation: Department of Extracorporeal Circulation, University  Medical Centre St. Radboud, Nijmegen, The Netherlands. A.Brinks@thchir.azn.nl
authors.forename: H J
authors.initials: HJ
authors.lastname: Brinks
authors.forename: P W
authors.initials: PW
authors.lastname: Weerwind
authors.forename: M W
authors.initials: MW
authors.lastname: Verkroost
authors.forename: I
authors.initials: I
authors.lastname: Nováková
authors.forename: M H
authors.initials: MH
authors.lastname: Brouwer
mesh_terms: D000818:Animals; D000990:Antithrombin III / Q000008:administration & dosage*; D020152:Antithrombin III Deficiency / Q000097:blood* / Q000150:complications / Q000601:surgery*; D016063:Blood Loss, Surgical; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D005343:Fibrinolytic Agents / Q000008:administration & dosage; D006493:Heparin / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D017762:Nadroparin / Q000008:administration & dosage / Q000009:adverse effects; D013552:Swine
chemical_list: D005343:Fibrinolytic Agents; D017762:Nadroparin; D000990:Antithrombin III; D006493:Heparin