title: The influence of surgical trauma on factor XaI and IIaI activity and heparin concentration after a single dose of low-molecular-weight heparin.
abstract: To study the influence of surgical trauma on the XaI and IIaI activity after injection of a low-molecular-weight heparin (LMWH) 24 patients undergoing elective cholecystectomy received one subcutaneous injection of the LMWH Fragmin. Each group of eight patients received either 2,500 or 5,000 XaI U 2 h before operation or 5,000 XaI U 10 h before surgery. For comparison an additional eight patients received 5,000 IU unfragmented heparin (UH) before operation. Laboratory analyses included amidolytically measured XaI- and IIaI-activities and direct measurements of heparin. Dose-dependent increase in the XaI- and IIaI-activity with maximal levels about 3-4 h after injection was seen. Patients given the LMWH 2 h before operation had lower levels of XaI-activity 2 h after injection than those receiving it 10 h before surgery, despite the same dose given. This correlated with the heparin concentrations, where the highest concentration was measured in patients given the LMWH 10 h before surgery. In conclusion, the surgical trauma of a cholecystectomy does not seem to have any major influence on the XaI- or IIaI-activity after administration of the studied LMWH. Alterations of the absorption and/or elimination rates cannot, however, be ruled out, but are related to factors other than the operative trauma per se, such as effects of premedication or circadian rhythmic variations.
authors.affiliation: Department of Surgery, Lund University, Malmö General Hospital, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Mätzsch
authors.forename: D
authors.initials: D
authors.lastname: Bergqvist
authors.forename: U S
authors.initials: US
authors.lastname: Burmark
authors.forename: E
authors.initials: E
authors.lastname: Holmer
authors.forename: K
authors.initials: K
authors.lastname: Söderberg
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015951:Factor Xa / Q000378:metabolism*; D005260:Female; D006493:Heparin / Q000097:blood*; D006495:Heparin, Low-Molecular-Weight / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood*; D011516:Prothrombin / Q000378:metabolism*
chemical_list: D006495:Heparin, Low-Molecular-Weight; D011516:Prothrombin; C025337:Factor IIa; D006493:Heparin; D015951:Factor Xa