Biotech Values

[DewDiligence]

Two more abstracts on antithrombin in sepsis/DIC:

>>
Molecular mechanisms underlying the role of antithrombin in sepsis

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_...

Crit Care. 2006 Feb 13;10(1):209 [Epub ahead of print]

Wiedermann CJ.

2nd Division of Internal Medicine, Department of Medicine, Central Hospital of Bolzano, Bolzano, Italy.

In disseminated intravascular coagulation (DIC) there is extensive crosstalk between activation of inflammation and coagulation. Endogenous anticoagulatory pathways are downregulated by inflammation, thus decreasing the natural anti-inflammatory mechanisms that these pathways possess. Supportive strategies aimed at inhibiting activation of coagulation and inflammation may theoretically be justified and have been found to be beneficial in experimental and initial clinical studies.

This review assembles the available experimental and clinical data on biological mechanisms of antithrombin in inflammatory coagulation activation. Preclinical research has demonstrated partial interference of heparin - administered even at low doses - with the therapeutic effects of antithrombin, and has confirmed - at the level of cellular mechanisms - a regulatory role for antithrombin in DIC.

Against this biological background, re-analyses of data from randomized controlled trials of antithrombin in sepsis suggest that antithrombin has the potential to be developed further as a therapeutic agent in the treatment of DIC. Even though there is a lack of studies employing satisfactory methodology, the results of investigations conducted thus far into the mechanisms of action of antithrombin allow one to infer that there is biological plausibility in the value of this agent. Final assessment of the drug's effectiveness, however, must await the availability of positive, prospective, randomized and placebo-controlled studies.
<<

>>
Antithrombin supplementation for anticoagulation during continuous hemofiltration in critically ill patients with septic shock: a case-control study

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_...

Crit Care. 2006 Mar 13;10(2):R45 [Epub ahead of print]

du Cheyron D, Bouchet B, Bruel C, Daubin C, Ramakers M, Charbonneau P.

Medical Intensive Care Unit, Caen University Hospital, Avenue cote de Nacre, 14033 Caen cedex, France

INTRODUCTION: Acquired antithrombin III (AT) deficiency may induce heparin resistance and premature membrane clotting during continuous renal replacement therapy (CRRT). The purpose of this study was to evaluate the effect of AT supplementation on filter lifespan in critically ill patients with septic shock requiring CRRT.

METHODS: We conducted a retrospective case-control analysis based on a 4-year observational study with prospectively collected data in two medical intensive care units in a university hospital. In all, 106 patients with septic shock underwent CRRT during the study period (55 during 2001 to 2002 and 51 during 2003 to 2004). Of these, 78 had acquired AT deficiency (plasma level below 70%) at onset of renal supportive therapy, 40 in the first 2-year period and 38 in the last 2-year period. In the latter intervention period, patients received AT supplementation (50 IU/kg) during CRRT each time that plasma AT activity, measured once daily, fell below 70%.

RESULTS : In a case-control analysis of the 78 patients with acquired AT deficiency, groups were similar for baseline characteristics, except in severity of illness as assessed by a higher Simplified Acute Physiology Score (SAPS) II after 2002. In comparison with controls, cases had a significantly greater AT level after AT supplementation, but not at baseline, and a smaller number of episodes of clots, without excess bleeding risk. The median hemofilter survival time was longer in the AT group than in the heparin group (44.5 versus 33.4 hours; p = 0.0045). The hemofiltration dose, assessed by the ratio of delivered to prescribed ultrafiltration, increased during intervention. AT supplementation was independently associated with a decrease in clotting rate, whereas femoral angioaccess and higher SAPS II were independent predictors of filter failure. However, mortality did not differ between periods; in the control period the observed mortality was significantly higher than predicted by the SAPS II score, unlike in the treatment period.

CONCLUSION: In sepsis patients requiring CRRT and with acquired AT deficiency, anticoagulation with unfractionated heparin plus AT supplementation prevent premature filter clotting and may contribute to improving outcome, but the cost-effectiveness of AT remains to be determined.
<<