Primary.—No deviation from the ordinary rules of surgery should be necessary in the majority of cases, but in a certain number the conditions are so unusual that the special considerations must be taken into account. The natural tendency to spontaneous cessation of primary hæmorrhage in small-calibre wounds is the first of these. Experience has shown that often mere dressing, or at any rate slight pressure, suffices to efficiently stanch immediate bleeding. Although, however, immediate control is to be obtained by such means, the cases of traumatic aneurism of every variety related in the next section show that the ultimate result is in many such cases by no means satisfactory.
Under these circumstances it may be said that the classical rule of ligation at the point of injury should never be disregarded. Against this, however, certain objections may be at once raised; thus in many cases both artery and vein need ligature, a consideration of much importance in the case of such vessels as the carotid and femoral arteries. Again in many of the injuries to the popliteal artery the wound directly communicated with the knee joint, a complication which, while it may be disregarded in civil practice, must take a much more important place in the circumstances under which many operations in military surgery are performed.
On the whole, it seems clear that the military surgeon must be guided by circumstances, since it may be far better to risk the chances of recurrent hæmorrhage, or the development of an aneurism or varix, all of which are amenable to successful treatment later, than those of gangrene of a limb or softening of the brain. As a general rule, therefore, on the field or in a Field hospital, primary ligature of the great vessels is best reserved for those cases only in which hæmorrhage persists, while in those in which spontaneous cessation has occurred, or in which bleeding is readily controlled by pressure, rest and an expectant attitude are to be preferred.
A word must be added as to the objections to distant proximal ligature for primary or recurrent hæmorrhage. In some situations this may be unavoidable, and it is sometimes successful, but none the less it is opposed to all rules of good surgery and a most uncertain procedure. It leaves the patient exposed to all the risks attendant on the employment of simple pressure. In one case which I saw, the third part of the subclavian artery had been ligatured for axillary bleeding; secondary hæmorrhage, as might have been expected, occurred, and that as late as five weeks after the operation. In another case ligature of the femoral artery for popliteal hæmorrhage was followed by the development of a traumatic aneurism in the ham.
Secondary.—In secondary hæmorrhage the treatment to be adopted depends upon the nature of the case. When the wound is aseptic, and bleeding the result of the separation of sloughs, local ligature is the proper treatment, and this was often successfully adopted, especially in the case of such arteries as the tibials. In septic cases, on the other hand, it is usually far better if possible to amputate, unless the general state of the patient and the local conditions are especially favourable.
When neither amputation nor direct local ligature is practicable, proximal ligature may be of use. Sometimes this may be obligatory in consequence of the difficulties attendant on direct local treatment. I saw a few cases successfully treated in this manner: in one the common carotid was tied (Mr. Jameson) for hæmorrhage from an arterial hæmatoma in connection with the internal maxillary artery. Although ligature of the external carotid would perhaps have been preferable, the result was excellent. When even this expedient is impracticable, local pressure is the only resort.
Lastly, as to the treatment of secondary interstitial blood effusions, I believe the best initial treatment is the expectant. If interference is needed, it is much more likely to be satisfactory the more chronic the condition has become, since the source of the bleeding may be impossible to discover. I never saw a patient's life endangered by the amount of such hæmorrhage, but if this should seem to be likely, local treatment is of course unavoidable. In several cases quoted below, incision and evacuation were followed by excellent results; in any such operation too much care to ensure asepsis is impossible.
Traumatic Aneurisms
The experience of the campaign fully bears out that of the past as to the steady increase of the number of aneurisms from gunshot wounds in direct ratio to diminution in the size of the projectiles employed. Every variety of traumatic aneurism was met with, and most frequently of all, perhaps, aneurismal varices and varicose aneurisms. While so experienced a military surgeon as Pirogoff could say, in 1864, that he had never seen a case of aneurismal varix, every young surgeon lately in South Africa has met with a series. Again, although the condition is a well-known one, it has been rather in connection with civil life; for the great majority of recorded cases were the result of stabs or punctured wounds such as are liable to be received in street brawls, or as a result of accidents with the tools of mechanics. Thus of ninety cases collected by K. Bardeleben in 1871, only 12 or 13.33 per cent. were the result of gunshot wound.
False traumatic aneurism or arterial hæmatoma.—This condition was met with comparatively frequently, and bears a very close relation to that already described under the heading of interstitial hæmorrhages. The latter might almost have been included here, since the difference between the two conditions depended merely on the size of the vessels implicated. The exact correspondence in the period of development of some of the arterial hæmatomata, and of the occurrence of the aseptic form of secondary hæmorrhage, also explains the pathology of the two conditions as identical; except that in the former the effused blood is retained in the tissues, while in the latter it escapes externally. The history of these cases was uniform and characteristic. A wound of the soft parts, or sometimes a fracture, was accompanied by a certain degree of primary interstitial hæmorrhage, which might or might not have been associated with external bleeding. A hæmatoma resulted in connection with the wounded vessel, the general tendency in the effusion being to coagulation at the margins and subsequent contraction. Meanwhile the opening in the artery became more or less securely closed by the development of thrombus, and possibly by retraction of the inner and middle coats of the vessel. With the return of full circulatory force as shock passed off, or with the resumption of activity and consequent freer movement of the limb, the temporary thrombus became washed away. The newly formed wall of soft clot bounding the effusion proved insufficient to withstand the full force of the blood pressure, and extension of the cavity resulted. In the more rapidly developing hæmatomata, temporary pressure by the effused blood on the bleeding vessels was also, no doubt, a common explanation of temporary cessation of increase in size.