HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): S. S. Ashraf Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Martin, P. Articles by Ashraf, S. S. Search for Related Content PubMed PubMed Citation Articles by Martin, P. Articles by Ashraf, S. S.

J Thorac Cardiovasc Surg 1996;111:493
© 1996 Mosby, Inc.

Letters to the Editor

Individualized patient heparinization and protamine reversal

Department of Cardiothoracic Surgery
Killingbeck Hospital
Leeds, United Kingdom

To the Editor:

We read with interest the article titled "The Impact of Heparin Concentration and Activated Clotting Time Monitoring on Blood Conservation" by Despotis and associates ¹ in the July 1995 issue of the Journal. This article examined an alternative anticoagulation management system (Hepcon HMS; Medtronic Hemotec, Englewood, Colo.) and blood conservation in adult cardiac surgical patients, highlighting once more the need for surgeons and anesthetists to reexamine their anticoagulation practices, which have remained largely unchanged for some two decades.

The suggestion that it may be possible (and seemingly appropriate) to administer doses of heparin according to an individual patient's preoperative blood response to heparin (and to subsequently maintain this level on bypass) may go someway toward eliminating "best fit" empirical protocols of heparin administration from the surgical arena. The fact that this dosage tailoring may be achieved without the need for increased administration of protamine, with its recognised "heparin-protamine complex" morbid sequelae, provides greater impetus for this alternative regimen to be formally examined. This study also confirms previous work ² from our unit with the Hepcon device, which suggested that empirical protamine administration protocols often result in excessive administration.

There is clearly a need to remain vigilant when one is confronted with the postoperative patient who is actively bleeding after increased heparin administration because heparin rebound may be a concern. Furthermore, a more thorough investigation of the determinants and markers of consumptive coagulopathy needs to be performed. We would be interested to learn whether the authors believe it is possible in the presence of heparin to draw firm conclusions regarding coagulation factor consumption solely on the basis of routine activated partial thromboplastin time and prothrombin time times. Perhaps less equivocal markers, such as fibrinopeptide A, thrombin-antithrombin complexes, or prothrombin fragment 1.2, may assist in confirming this event.

Attempts to delineate purely heparin concentration–dependent postoperative sequelae from those of heparin-protamine complexes are currently under consideration within our unit, as are additional studies assessing the contribution of heparin-bonded cardiopulmonary bypass circuitry to the anticoagulation-neutralization equation. The contribution of Despotis and associates ¹ is therefore timely and welcomed by our group.

References

1. Despotis GJ, Joist JH, Hogue CW, et al. The impact of heparin concentration and activated clotting time monitoring on blood coagulation. J THORAC CARDIOVASC SURG 1995;110:46-54.[Abstract/Free Full Text]
   
2. Horkay F, Martin P, Rajah SM, Walker DR. Response to heparinization in adults and children undergoing cardiac operations. Ann Thorac Surg 1992;53:822-6.[Abstract]
   

This Article Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): S. S. Ashraf Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Martin, P. Articles by Ashraf, S. S. Search for Related Content PubMed PubMed Citation Articles by Martin, P. Articles by Ashraf, S. S.