Various causes have been assigned as pro ducing secondary haemorrhage, the chief of which is the too extensive detachment of the vessel from its surrounding connexions during the operation, an opinion that I cannot think is borne out by observation. If it is supposed that this dissection of an artery is injurious by depriving it of its vascularity, and diminishing its supply of nutrient blood, the result should be analo gous if not exactly like that which takes place when the vessel is deprived of its cellular coat from any other cause, that is, a slough should form on it, on the separation of which the haemorrhage should occur violently and with a gush. An illustration of this is familiarly observed in the phagedenic ulceration of buboes in the groin, where the artery for a time appears to resist the destructive process, and lies de nuded like a white cord at the bottom of the sore ; but one or more black spots form upon it, which are really specks of mortification, on the detachment of which the bleeding commences with awful violence. Perhaps consecutive haemorrhage does occasionally occur from the burrowing of an abscess along the coats of an artery, an example of which is on record in Mott's case of ligature of the innominata, in which the bleeding occurred ten days after its removal, was so violent from the first as to be with much difficulty restrained, and de stroyed the patient on the day but one after wards. But it may be observed, that the phe nomena attendant on these cases are different from those already described as characteristic of the common forms of the accident—that they usually occur at a later period, even long after the separation of the ligature might have inspired confidence in the result, and they are evidently more hopeless, for neither pressure nor ligature can here be of the slightest avail. Farther, to appeal to experience, the best and surest foundation of every scientific principle, is it not a matter of daily observation that this much-dreaded insulation of the artery can have but little effect on the ultimate termination of the case, as operations performed in this respect in the most bungling and clumsy man ner occasionally end well, whilst the utmost caution in not exposing more of the artery than will barely permit the passage of the ligature cannot ensure the patient from secondary hw morrhage ? When the bleeding is occasioned by any defect in the operation, such as tying the cord too loosely, including adjacent structures, &c. it usually appears so early as from the third to the fifth day after the operation, and there is another form of early consecutive haemorrhage that occurs in consequence of the artery itself being inflamed or otherwise diseased at the time of the operation. An example of this is too often met, when, as a means of controlling con secutive a fresh ligature has been tied on the trunk somewhere higher up or nearer to the heart. It has been remarked by Dupuytren, that an artery under such circum stances is in a most unfavourable condition for an operation ; it is surrounded by cellular tissue in a state of inflammation, in which it par ticipates ; its coats are rendered so brittle that they break down immediately under the liga ture, and the haemorrhage returns in a few hours.* It is worthy of remark that in this case also the bleeding comes from the orifice of the vessel below the ligature ; indeed, in all cases of divided artery, whether by a cutting instrument or by a cord, the remedial process seems to be different in the two fragments, being far more perfect in the upper. On this point the statements of Mr. Guthrie are most valuable because founded on extensive ob servation, and he remarks in the case of an artery, the bleeding from which had ceased of itself, that if it recurs it is more likely to proceed from the lower than the upper portion. This latter fact is the more important as it bears upon another supposed cause of secondary hemorrhage, namely, the state of tension in which an artery inclosed in a ligature is ne cessarily placed.
Many years ago it occurred to Mr. Aber nethy that, " as large arteries do not ulcerate when they are tied upon the surface of a stump after amputation, it would be right to tie them in cases of aneurism as nearly as possible in the same manner and under the same circum stances." It is familiarly known that he re commended for this purpose the application of two ligatures with the division of the artery between them ; and he argues that the divided portions would be like the large vessels on the surface of the stump in possession of all their surrounding connexions, whilst they are left in a lax state in consequence of their division.
But the cases after all are not analogous, be cause in the stump there is no inferior portion of vessel from which it has been seen the chief cause of apprehension arises—it has been cut away, and only the superior remains, from which it is rare to meet with hemorrhage under ordinary circumstances. In Mr. Aber nethy's operation it is only the upper division of the vessel that bears analogy with the artery of the stump, and the insufficiency of the removal of thetension in preventing haemor rhage from the inferior is proved, first, by the fact that consecutive haemorrhage occurs in cases that have been thus treated proportion ally as often as in others ; and, secondly, by Mr. Guthrie's observation that in the case of a wound there is no tension : the artery has been fairly divided, and its surrounding con nexions are undisturbed ; yet the bleeding, having ceased spontaneously, or, in other words, having been controlled by the power of nature alone, may recur, and when it does the blood flows from the lower orifice.
Others have believed that the accidental position of a collateral branch near to the ligature might be a cause of consecutive haemorrhage by interfering with the formation of the internal coagulum. I have already stated that the importance attached to this coagulum was greater than it deserved ; and it will be only necessary here to add, that I have tied the common carotid artery within an eighth of an inch of its origin from the inno minata without the slightest ill consequence from that circumstance.
It has been pretty generally believed that in those cases which have ended favourably,a mild, healthy, and Mitigated process of inflammation had been • established which terminated in the effusion of lymph and the obliteration of the vessel, whilst in the unfavourable the inflam mation was more violent and ran into ulce ration. Nothing is more familiar than to hear of the ulceration of an artery in connexion with and as the cause of secondary haemor rhage, yet the existence of such ulceration is very questionable. Arteries are not prone to ulcerate. It has been shewn that in the midst of phagedenic destruction, the artery escapes for a length of time, and when it is attacked, it is rather by mortification: and the appear ance of arteries traversing in safety the cavities of tubercular abscesses in the lungs, where they have lain for weeks or months bathed in purulent matter, should make us hesitate in speaking so boldly of ulceration in these struc tures. The fact, as observed on dissection, appears to be quite otherwise, and the haemor rhage to be occasioned not by a hyper-activity of inflammation tending to ulceration, but by an absence or failure of the process altogether.
As persons, the subjects of consecutive hae morrhage, seldom die (at least in this country) of actual loss of blood, it is not easy to pro cure a dissection which can satisfactorily skew the condition of the vessel at the moment it begins to bleed, and no subsequent examination can be relied on, because the pressure or other means used to stop the bleeding may in the course of a very few days alter the appearances completely. I have availed myself of every opportunity that occurred, and state the results, not with the presumptive hope of being able to establish any general principle, but to excite others to inform themselves on every case fa vourable to the further prosecution of the in quiry, and, perhaps, in some respects to justify the opinions I have formed. It is worthy of re mark, that secondary haemorrhage occurs much more frequently in the arteries of tilt lower than of the superior extremities or of the neck, and all the specimens I have examined were of the femoral that had been tied from half an inch to an inch and half below the profunda. In all, the portion of the artery above the ligature gave indications of inflammation extending nearly as high as the common iliac ; the lining membrane more or less vascular; the portion of the vessel between the ligature and profunda of its natural size or slightly diminished ; its cavity occupied by the remains of a coagu lum. Above that point the calibre of the trunk was evidently increased, and the texture of its coats less resisting. The inferior por tion resembled a vessel simply cut across, its calibre diminished, its internal coat dis coloured, its divided edge smooth and even, not rough, jagged, or irregular, as would pro bably be the case if it had been the seat of ulceration.