ARTERY, PATHOLOGICAL CONDITIONS OF. 



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ease in the artery of the latter. Indeed, in 

 examining and comparing the artery of a sheep 

 or a dog with that of man, some very obvious 

 differences are apparent: the former is firmer 

 if not actually thicker in its coats ; it maintains 

 its circular form more completely, and seems to 

 possess the quality of elasticity in a greater 

 degree of perfection. These circumstances, 

 however, are insufficient to account for that 

 comparative freedom from disease ; and pro- 

 bably the greater susceptibility of man may be 

 traced to the indulgence of certain habits and 

 propensities from which the animal is debarred, 

 and which, in many other instances as well as 

 in this, seem to be the predisposing causes 

 of disease in the human race. 



The'surgical pathology of the arteries presents 

 itself in two different though equally interesting 

 points of view, one having reference to the 

 effects of a wound or other injury to a healthy 

 vessel, embracing a consideration of the pro- 

 cess by which such injury is remedied or re- 

 paired by the efforts of nature alone or by the 

 assistance of art, and the circumstances that 

 influence its success or failure ; the other refer- 

 ring to the appearances and consequences of 

 disease, either as it commences idiopathically 

 within the vessel itself, or is propagated from 

 adjacent parts or structures to it. A lesion 

 of the structure of an artery is of but slight 

 importance provided its function is unimpaired, 

 that is, as long as the blood it was destined to 

 circulate passes through it or is conveyed by 

 some other channel in the natural course of the 

 circulation : even the aorta has been obliterated 

 without any serious inconvenience to the indi- 

 vidual in whom it occurred. But when the 

 lesion is of such a nature as to interfere with 

 this function, when the blood is allowed to 

 escape either externally as from an open wound, 

 or internally as in the different species of aneu- 

 rism, results of a most formidable nature 

 ensue, greatly modified, however, in their cha- 

 racter and consequences by a number of cir- 

 cumstances highly deserving of attention. 



Wounds and injuries of artej-ies. It 

 cannot have escaped observation that the 

 nature of the wound or rather of the substance 

 that occasioned it exerts a striking influence 

 on the phenomena both of haemorrhage and of 

 the process by which it is restrained. Lacerated 

 wounds seldom bleed, although the torn artery 

 may be left hanging out an inch or more be- 

 yond the adjacent surface. Gun-shot wounds, 

 also, if the artery is completely divided, are 

 not often followed by haemorrhage, although 

 some instances to the contrary occasionally 

 happen ; but if the vessel is only notched or 

 partially cut, the bleeding is as profuse as from 

 any other cause. If an artery is wounded by a 

 cutting instrument or by puncture, however, the 

 blood is poured out most freely ; yet even here 

 there are varieties, according to the size and 

 importance of the vessel, the extent and direc- 

 tion of the accompanying wound, and the cir- 

 cumstance of the division of the artery being 

 partial or complete. In like manner the sub- 

 sequent progress of the case will exhibit con- 

 siderable variety, and demonstrate the fallacious 



views of those who, grounding their opinions oa 

 experiment, would limit the process of recovery 

 to one operation, and regard the efforts of 

 nature as alike in all, whereas, as has been 

 remarked by Mr. Guthrie, this process essen- 

 tially depends on the size and variation of 

 structure of the artery ; it is not the same in 

 large as in small arteries ; and it is not even 

 quite the same in the upper and lower ends of 

 the same artery. 



\Vhen a limb has been torn off by a cannon- 

 shot, by the fall of a tree on it, or by any simi- 

 lar violence, the arteries do not bleed : very 

 frequently the main trunk -is seen hanging an 

 inch or more from the wound, pulsating, or at 

 least receiving an impulse from the sound 

 portion of the vessel, though (as far as I have 

 observed) not containing blood within it. It 

 hangs white, bloodless, and flaccid in the 

 wound, not very unlike a piece of narrow 

 wetted tape, and is smaller at its extremity 

 than at any other part. This narrow point, 

 which, according to Mr. Guthrie, is formed by 

 the contraction of the artery, is also in his 

 opinion the only barrier to the escnpe of the 

 blood ; for in a case of this description he cut 

 oft" the end of the artery at less than an eighth 

 of an inch from the extremity, when it bled 

 with the usual vigour. The extraordinary op- 

 portunities this gentleman has enjoyed, and 

 the accuracy of observation which his writings 

 evince, entitle his opinions to be received with 

 great deference, although in a physiological point 

 of view it is difficult to conceive how an artery 

 subjected to such a lacerating force should not 

 have its vital properties so much impaired as 

 to prevent its contracting at all, more par- 

 ticularly at the spot where it was torn across, 

 and where, therefore, the greatest injury was 

 sustained. At the same time there is no other 

 mode of explaining the case. All that portion 

 of the artery that is pendulous from the wound 

 appears to be smaller in diameter than in its 

 healthy state ; there is cellular tissue at its torn 

 extremity, but it is not injected with blood, 

 and the coagulum, if any, within the vessel, is 

 so small as to be incapable by its mechanical 

 resistance of preventing the escape of the blood. 

 As there are scarcely any two accidents at- 

 tended by exactly the same degree of injury, 

 it is probable that nature in such cases possesses 

 different resources. In one case where the leg 

 had been torn off by the falling of a tree, and 

 left attached merely by a portion of the skin 

 over the gastrocnemius muscle, the posterior 

 tibial artery hung nearly three inches from the 

 wound. As the man had been carried a dis- 

 tance of eleven miles, and seemed much ex- 

 hausted, it was not deemed right to attempt 

 more at the moment than merely to relieve him 

 of the annoyance of the pendulous portion of 

 the limb by cutting through the skin. This 

 was performed incautiously, for no inconve- 

 nience was apprehended ; about an inch of the 

 extremity of the artery was removed, and it 

 bled just as in Mr. Outline's case. In another 

 instance where the arm was shattered by a 

 steam-engine with such violence that some of 

 the muscles torn from their attachments re- 



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