VEIN. 



1395 



a lardaceous aspect and character. By and 

 by a turbid puriform fluid is often found de- 

 posited at intervals in the cellular texture ; in 

 some instances where the suppuration is vi- 

 gorous in the vicinity of the vein, the latter 

 traverses the purulent channel for a consider- 

 able space, denuded of its entire circumfer- 

 ence. Here the membranes of the vein gra- 

 dually soften, and at length melt down, so to 

 speak, until no further vestige of their texture 

 is discernible within the common centre of 

 suppuration."* If, however, this circumscrip- 

 tion of the pus by means of coagulum does not 

 occur, and it floats through the vascular sys- 

 tem, it produces a variety of secondary effects 

 remarkable and important in their results. 



The products of this secondary action are 

 known as "purulent deposits" or " lobular 

 abscesses." Strictly speaking, they are not 

 deposits of pus; but the pus is "translated" 

 from one part to another, and there becomes 

 the originator and centre of a fresh ab.scess. 



The actual mode of production of these lo- 

 bular abscesses has been the subject of much 

 discussion ; but the evidence upon the va- 

 rious points appears to resolve itself into the 

 following explanation. The pus-cells being 

 bodily introduced into a vein, or generated in 

 it, pass forward in the circulation till arrested 

 in the capillaries by their size being too great 

 to admit of their passage : they then excite 

 inflammation of the parenchyma of the affected 

 organ, which leads to condensation, and, sub- 

 sequently, to suppuration : the pus-cells being 

 the excitants of the inflammation, which is 

 suppurative, not only from its intensity, but 

 from the fact that pus germs are furnished by 

 the same body as originates the inflammation, 

 and thus more pus is generated. 



The appearances of these local abscesses, 

 which are, strictly speaking, foreign to our 

 present subject, are determined by the cha- 

 racter of the organ in which they occur. 



There appears to be some general laws as it 

 respects the development of these abscesses. 

 They occur in those organs which are most 

 vascular, and through which the largest quan- 

 tity of blood passes in the smallest space of 

 time; thus the lungs and liver are affected the 

 most abundantly. Again, after the blood has 

 been infected and the pus added to it, that 

 system of capillaries is first affected, through 

 which the fluid first passes ; the capillaries, as 

 it were, filtering off* the pus-cells and retaining 

 them. Thus, if pus gets into the systemic 

 veins, the capillaries of the lungs will be the 

 first to arrest their progress ; and when this 

 happens, as is generally the case, lobular ab- 

 scesses are most abundantly, or exclusively, 

 found in those organs, and when found else- 

 where also are most advanced in the lungs : 

 when, however, the portal system is the vehicle 

 of the pus, as occasionally happens after oper- 

 ations on the rectum, for example, we find the 

 abscesses in the liver. These laws are quite 

 correct in the main ; but there are some ex- 

 ceptions to them, and these exceptions are 



* Hasse, loc. cit. p. 18. 



quite explicable ; for though pus-cells are for 

 the most part too large to pass capillaries, 

 especially with their tendency to coagulate 

 blood, they may nevertheless pass through 

 some of the larger ones ; and it must be ad- 

 mitted that disintegrated pus globules may 

 pass through the smallest vessels : hence, in 

 some instances, the laws here suggested are 

 not exemplified. 



The results of phlebitis are either suppura- 

 tion, resolution, or obstruction, the consequence 

 of organisation of the effused lymph. Upon 

 the latter subject some observations are ne- 

 cessary. 



Obliteration of Veins. Obliteration of veins, 

 the result of phlebitis, may be either incom- 

 plete or complete. Hasse mentions two forms 

 of partial obliteration of veins ; the first of 

 which has also been described by Carswell. 

 This form consists of a thickened and turgid 

 condition of the vessel's walls, as if they had 

 been macerated ; at the same time they are 

 closelv connected with the surrounding areo- 

 lar tissue. Within the vein, and intimately 

 connected with the lining membrane, is a hol- 

 low cylinder of fibrin, firm and whitish on its 

 exterior, and soft and dark-coloured within ; 

 the interior being bathed with the circulating 

 blood. Dr. Carswell's explanation of this, in 

 which Hasse coincides, is that the soft centre 

 of the plug is carried away before the circu- 

 lating current, whilst the exterior becomes 

 organised and united with the interior of the 

 vein. 



In the other form he describes the vein as 

 reduced to a whitish cord, and filled with an 

 organised plug. ** Betwixt this plug and the 

 thickened coats of the vessel, round about 

 the periphery of the former, were several little 

 canals, which, running along the whole extent 

 of the vein, had already begun to re-establish 

 the circulation. In all probability the impulse 

 of the blood below had, during the first period 

 of inflammation, here and there severed the 

 plastic plug from the parietes of the vessel ; 

 subsequently, the above plug being organised, 

 and the intervening blood absorbed, several 

 peripheral channels would form, instead of a 

 single central one." * 



In complete obliteration the vein diminishes 

 in size, shrinks nearly to a cord, and becomes 

 pale and soft. The plug also becomes reduced 

 in size and organised, and adheres firmly 

 to the lining of the vein. How the plug re- 

 ceives its vessels and communicates with the 

 vasa vasorum of the vein, I am not prepared 

 to state. But fibrin thus isolated probably 

 has the inherent power of generating vessels, 

 which ultimately communicate with those of 

 neighbouring textures. The secondary con- 

 sequences of obliteration of veins, oedema, 

 Phlegmasia dolens, &c. cannot here be con- 

 sidered. 



Healing of Wounds in Veins. The condi- 

 tion of the wound and its mode of healing de- 

 pend upon the character and direction of the 



* Hasse, loc. cit. p. 26. I beg to make abundant 

 acknowledgments to the very valuable writings of 

 this author, from whom I have drawn largely. 

 4 u 2 



