hirudin and Aortic-Aneurysm--Abdominal

To retrospectively evaluate the safety and effectiveness of the use of bivalirudin, a direct thrombin antagonist, compared with unfractionated heparin in endovascular aneurysm repair (EVAR).. Between March 1994 and September 2007, 740 consecutive patients (mean age, 75.7 y +/- 7.7; 69 women) underwent elective EVAR for infrarenal abdominal aortic aneurysm. Bivalirudin was used in 98 of these 740 (13.2%) and unfractioned heparin was used in the other 642 (86.8%). Complications were classified according to the Society of Vascular Surgery/International Society for Cardiovascular Surgery criteria. Major bleeding was defined as clinically overt blood loss resulting in a decrease of hemoglobin of more than 3 g/dL, any decrease in hemoglobin of more than 4 g/dL, transfusion of 2 U or more of red blood cells, or intracranial or retroperitoneal hemorrhage.. Grade 1 major complications were observed in 161 of 642 patients (25.2%) in the heparin group and 12 of 98 patients (12.2%) in the bivalirudin group (P = .0046), whereas the incidences of grade 3 major complications were not significantly different between groups (P = .57). The rate of total complications was higher in the heparin group than in the bivalirudin group (247 of 642 [38.5%] vs 21 of 98 [21.4%]; P = .001). Major bleeding occurred in 10 of 98 patients (10.2%) receiving bivalirudin and in 91 of 642 patients (14.2%) receiving heparin (P = .34). One of 21 major complications (4.76%) in the bivalirudin group and 12 of 247 major complications (4.86%) in the heparin group were attributable to thrombosis (P = 1.0).. Bivalirudin is a safe and feasible alternative to unfractionated heparin in patients undergoing EVAR.

Topics: Aged; Aged, 80 and over; Anticoagulants; Aortic Aneurysm, Abdominal; Blood Loss, Surgical; Blood Transfusion; Blood Vessel Prosthesis Implantation; Feasibility Studies; Female; Hemoglobins; Hemorrhage; Heparin; Hirudins; Humans; Male; Peptide Fragments; Postoperative Hemorrhage; Recombinant Proteins; Retrospective Studies; Thrombin; Treatment Outcome

A 60-year-old man was admitted to the hospital with aortic dissection. An operative excision and replacement with a Y-graft was performed. Postoperatively he developed multiple organ dysfunction and required intermittent haemofiltration (anticoagulation with heparin). An ischemia of the left leg occurred at the third postoperative day. The initial platelet count was 99,000/microliter. Continuous haemofiltration (CVVH) was started three days later. Thrombotic obstructions of haemodialysis filters and catheters occurred frequently and heparin-induced thrombocytopenia (HIT II) was suspected. Antibodies against heparin were found in the HIPA test. Despite heparin free citrate dialysis and anticoagulation with danaparoid thrombotic obstructions of filters and catheters continued. Therefore the anticoagulation therapy during CVVH was changed to recombinant hirudin (lepirudin). Starting dose was a bolus of 0.01 mg/kg bw followed by the same amount as maintenance dose per hour. Anticoagulation was adjusted to an increase of aPTT (activated partial thromboplastin time) to 1.5-2 times its normal value. A dose of 0.005 mg/kg bw/h lepirudin was sufficient to maintain adequate anticoagulation. After changing to lepirudin no further catheter obstructions were observed and the platelets recovered slowly. Renal function improved and five weeks after admission endogenous creatinine clearance showed a value of 25 ml/min. We conclude that lepirudin is an effective anticoagulant during CVVH in patients with HIT II. In partly permeable polysulfon filters a dose of 0.005 mg/kg bw/h lepirudin is sufficient to maintain adequate anticoagulation. Monitoring anticoagulation by measuring the increase of aPTT (factor 1.5-2.0) seems to be safe. However, optimally the r-hirudin concentration should be measured directly using the Ecarin clotting time.

Topics: Anticoagulants; Aortic Aneurysm, Abdominal; Aortic Dissection; Blood Vessel Prosthesis Implantation; Hemodiafiltration; Heparin; Hirudin Therapy; Hirudins; Humans; Male; Middle Aged; Multiple Organ Failure; Recombinant Proteins; Thrombocytopenia; Treatment Outcome