可吸收止血纱布的临床应用和评价(外文文献)

cellulose* is a new, specifically hemostatic material which is readiIy absorbed without adverse reaction when Ieft in various body tissues for the purpose of controhing hemorrhage. It is supphed in the form of gauze-like strips of various sizes and Iengths or carded fiber pads simiIar in appearance to pure absorbent cotton. This latter form is designed primariIy for neurosurgery, intraora1 and intranasa1 procedures; its use in these fieIds faIIs beyond the scope of this paper. Both types are prepared from a very pure form of regenerated ceIIuIose composed of fibers of uniform diameter and chemical composition made by the viscose process, and subsequentIy oxidized to a carefuIIy controIIed carboxy content as described by Ashton and Moser [I]. By this method a soIution formed from the treatment of cotton Iinters, or other suitabIe source of aIphaceIIuIose, with an aIkaIinized organic soIvent is forced through spinerettes of suitabIe diameters into a coaguIating bath where the ceI1uIose is regenerated as a continuous fiber which can then be knitted or carded into the type of fina product desired. The regenerated ceIIuIose resuIting from this process is, of course, far purer than the origina ceIIuIose with which the process was started. The material is of uniform moIecuIar weight
New York, ANDALVIN LEBENDIGER, M.D., Louisville, Kentucky
From tbe Surgical and Laboratory Divisions, tbe Montefieor Hospital, New York, New York, and tbe Jobnson PP Jobnson Research Foundation, New Brunswick, New Jersey. Tbis study was supported by a grant from tbe Department of Clinical Research of Johnson @ Jobnson, New Brunswick, New Jersey.
0
XIDIZED regenerated
*The mate&I used in this study was SurgiceI’ AbsoFra Baidu bibliotekbable Hemostat, suppIied by Johnson &Johnson, New Brunswick, New Jersey.
and the fibers which it forms are of uniform diameter throughout their Iength. In this respect they differ from cotton fibers, which are tapered and thicker at one end than the other. This consideration is important since it is because of the physica and chemica1 uniformity of the regenerated material that the a11 important step of oxidation can be carried out in a uniform and reproducible manner, which is not the case when natura1 cotton is used, as it is in the oIder type products, as the starting materia1 for the oxidation process. The oxidation process is carried out after the product has been fabricated in fina form, the primary alcoho1 radicaIs of the ceIIuIose moIecuIe being oxidized to carboxyl (- COOH) groups and carefuIIy purged of undesirabIe byproducts by subsequent neutraIization and washing. By this process the desired degree of oxidation of 20 per cent can be achievec1 with a uniformity which varies within limits of onIy + 1.0 per cent. This cIose contro1 is made possibIe by the fact that regenerated ceIIu1ose has a uniform and reproducible moIecuIar size distribution, whiIe natura1 cotton is quite variable. For these reasons it has been possibIe to obviate the extreme variation in absorbability, tissue reactivity and hemostatic effectiveness characteristic of the oIder product [2--101. Not onIy is the new product extremeIy uniform, it is exceedingIy pure, the tota of a11extraneous substances present being Iess than 15 parts per miIIion. The specia1 characteristics which make this product usefu1 as an absorbabIe hemostatic agent arise from the fact that the regenerated ceIIuIose is oxidized to the true chemica1 compound, poIyanhydrogIucuronic acid, which, in addition to having hemostatic properties, is
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Hurwitt,
Henderson,
Lord, GitIitz
and Lebendiger
soIubIe in weak aIkaIies and can be hydroIyzed by living tissues. Such chemical degradation, accompIished by enzymes of the carbohydrase system, contributes to the ease with which the material is absorbed in body tissues and the minima1 degree of tissue response occasioned by its impIantation. When exposed to bIood, either in vitro or under surgica1 conditions, the material, which has a pH of 3.5 to 4.5, turns very dark brown or black due to the formation of acid hematin. The acid nature of the materia1 itseIf probabIy produces some hemostatic effect due to styptic action. In addition, hemostasis very probabIy depends in part upon the marked affmity of poIyanhydrogIucuronic acid for hemoglobin and other bIood proteins. A Iarge hydrated aggregate is thus formed which controIs bIeeding by simpIy acting as a cork in the mouths of the vesseIs, and secondariIy suppIying a scaffoIding for cIot formation. The hemostatic activity of SurgiceI probably does not depend upon the physioIogic cIotting mechanism per se, but on the formation of what might be termed an “artifrcia1 cIot” as described. This probabIy expIains its effectiveness, which has been observed by others in controIIing surgica1 bIeeding in many cases of hemophiIia, thrombocytopenic purpura and simiIar bIood dyscrasias, aIthough in one instance (vide infra) it was noted that cIotting of heparinized bIood did not occur in vivo. Hemostatic action is not enhanced by the addition of other agents such as thrombin (which in any case wouId be destroyed by the Iow pH of the gauze).
A New Surgical
Absorbable
AND CLINICAL
Hemostatic
EVALUATION
Agent
EXPERIMENTAL
ELLIOTTS. HURWITT, M.D., New York, New York, JOHN HENDERSON,M.D., GEOFFREYH. LORD, PH.D., New Brunswick, New Jersey, GEORGE F. GITLITZ, M.D., New York,