Disappearance Rate of Concentrated Proconvertin Extracts in Congenital and Acquired Hypoproconvertinemia*

Abstract

While developing methods for extraction and concentration of various adsorbable blood clotting factors (1-3), we found that an extract made by Al(OH)3 adsorption of citrated plasma contained large amounts of proconvertin and only small quantities of prothrombin, Stuart factor (4), and plasma thromboplastin component (PTC) (5). The present report is concerned with the disappearance rate of proconvertin following the rapid intravenous administration of this extract to nine patients with congenital or acquired hypoproconvertinemia.In their original description of congenital proconvertin 1 deficiency, Alexander, Goldstein, Landwehr and Cook (6) indicated that the corrective effect of normal plasma or serum transfusion was lost within 24 hours. After transfusion of whole blood to an infant with severe congenital hypoproconvertinemia, Hitzig and Zollinger (7) found the proconvertin half-life to be 115 to 135 minutes. The half-life was 57 minutes following injection of 20 ml of an extract having a proconvertin potency 30 times that of normal plasma.Frick (8) stated that the half-life of proconvertin was 5.5 to 6 hours following plasma transfusion in normal subjects made hypoproconvertinemic by the intravenous administration of Warfarin sodium.2 Didisheim, Loeb, Blatrix and Soulier (9) stated that the half-life of proconvertin was 50 to 55 hours, following intravenous admin-*

The Survival of Factor Viii (Antihemophilic Globulin) and Factor Ix (Plasma Thromboplastin Component) in Normal Humans*

“…We do not know whether our survivals are longer because of the difference in technique of measurement or because of an increased rate of utilization of Factor VIII in hemophilic subjects as compared with normals. The 8.4 day half-life of the second phase of our Factor IX survival curves is strikingly different from the 1-to 4-hour half-life reported by Hoag and colleagues (18). These authors, however, did not follow the Factor IX survival curve beyond 7 hours posttransfusion.…”

“…Here, the first component has a corrected half-life of 26 hours, and the second component has a half-life of 7.6 days. (18) in their study of Factor IX survival drew multiple samples during the early phase after transfusion and noted a rapid disappearance of Factor IX during the first 20 minutes after transfusion. Unfortunately, we did not study this very early phase.…”

Factor VII Survival Studies in Factor VII Padua Abnormality

“…This observation is in agreement with in vitro data which indicate that these patients lack inhibitors in their plasma [6]. It is interesting to note that similar results have been obtained by us in another abnor mality of the prothrombin complex factors, namely factor X Friuli disorder [4], The survival times observed are well in line with those reported in the literature [1,2,[8][9][10][11][12]. However, it is worth mentioning that some of the studies carried out dealt with the infu sion of large quantities of plasma which made all but impossible to calculate a satis factory half-life.…”

Physiological Basis for Transfusion Therapy in Hemorrhagic Disorders: A Critical Review

“…Factor VII: Voss and Waaler96 found no tendency to bleed in patients with hereditary partial factor VII deficiency with levels over 25 per cent of normal. It is known that patients receiving long term oral anticoagulant therapy do not necessarily bleed at surgery with levels of prothrombin and of factors VII, IX and X in this region.119 48 However, Hoag, et al, 46 have noted one patient with levels of 26 to 35 per cent of factor VII who has had numerous bleeding episodes. Shulman89 has repeatedly controlled epistaxis in a child with severe congenital factor VII deficiency by achieving levels in the region of 25 per cent with transfusions of 250 mI.…”