As a rule, reactionary hæmorrhage takes place from small vessels as a result of the displacement of occluding clots, and in many cases the hæmorrhage stops when the bandages and soaked dressings are removed. If not, it is usually sufficient to remove the clots and apply firm pressure, and in the case of a limb to elevate it. Should the hæmorrhage recur, the wound must be reopened, and ligatures applied to the bleeding vessels. Douching the wound with hot sterilised water (about 110° F.), and plugging it tightly with gauze, are often successful in arresting capillary oozing. When the bleeding is more copious, it is usually due to a ligature having slipped from a large vessel such as the external jugular vein after operations in the neck, and the wound must be opened up and the vessel again secured. The internal administration of heroin or morphin, by keeping the patient quiet, may prove useful in preventing the recurrence of hæmorrhage.

Secondary Hæmorrhage.—The term secondary hæmorrhage refers to bleeding that is delayed in its onset and is due to pyogenic infection of the tissues around an artery. The septic process causes softening and erosion of the wall of the artery so that it gives way under the pressure of the contained blood. The leakage may occur in drops, or as a rush of blood, according to the extent of the erosion, the size of the artery concerned, and the relations of the erosion to the surrounding tissues. When met with as a complication of a wound there is an interval—usually a week to ten days—between the receipt of the wound and the first hæmorrhage, this time being required for the extension of the septic process to the wall of the artery and the consequent erosion of its coats. When secondary hæmorrhage occurs apart from a wound, there is a similar septic process attacking the wall of the artery from the outside; for example in sloughing sore-throat, the separation of a slough may implicate the wall of an artery and be followed by serious and it may be fatal hæmorrhage. The mechanical pressure of a fragment of bone or of a rubber drainage tube upon the vessel may aid the septic process in causing erosion of the artery. In pre-Listerian days, the silk ligature around the artery likewise favoured the changes that lead to secondary hæmorrhage, and the interesting observation was often made, that when the collateral circulation was well established, the leakage occurred on the distal side of the ligature. While it may happen that the initial hæmorrhage is rapidly fatal, as for example when the external carotid or one of its branches suddenly gives way, it is quite common to have one, two or more warning hæmorrhages before the leakage on a large scale, which is rapidly fatal.

The appearances of the wound in cases complicated by secondary hæmorrhage are only characteristic in so far that while obviously infected, there is an absence of all reaction; instead of frankly suppurating, there is little or no discharge and the surrounding cellular tissue and the limb beyond are œdematous and pit on pressure.

The general symptoms of septic poisoning in cases of secondary hæmorrhage vary widely in severity: they may be so slight that the general health is scarcely affected and the convalescence from an operation, for example, may be apparently normal except that the wound does not heal satisfactorily. For example, a patient may be recovering from an operation such as the removal of an epithelioma of the mouth, pharynx or larynx and the associated lymph glands in the neck, and be able to be up and going about his room, when, suddenly, without warning and without obvious cause, a rush of blood occurs from the mouth or the incompletely healed wound in the neck, causing death within a few minutes.

On the other hand, the toxæmia may be of a profound type associated with marked pallor and progressive failure of strength, which, of itself, even when the danger from hæmorrhage has been overcome, may have a fatal termination. The prognosis therefore in cases of secondary hæmorrhage can never be other than uncertain and unfavourable; the danger from loss of blood per se is less when the artery concerned is amenable to control by surgical measures.

Treatment.—The treatment of secondary hæmorrhage includes the use of local measures to arrest the bleeding, the employment of general measures to counteract the accompanying toxæmia, and when the loss of blood has been considerable, the treatment of the bloodless state.

Local Measures to arrest the Hæmorrhage.—The occurrence of even slight hæmorrhages from a septic wound in the vicinity of a large blood vessel is to be taken seriously; it is usually necessary to open up the wound, clear out the clots and infected tissues with a sharp spoon, disinfect the walls of the cavity with eusol or hydrogen peroxide, and pack it carefully but not too tightly with gauze impregnated with some antiseptic, such as “bipp,” so that, if the bleeding does not recur, it may be left undisturbed for several days. The packing should if possible be brought into actual contact with the leaking point in the vessel, and so arranged as to make pressure on the artery above the erosion. The dressings and bandage are then applied, with the limb in the attitude that will diminish the force of the stream through the main artery, for example, flexion at the elbow in hæmorrhage from the deep palmar arch. Other measures for combating the local sepsis, such as the irrigation method of Carrel, may be considered.

If the wound involves one of the extremities, it may be useful; and it imparts confidence to the nurse, and, it may be, to the patient, if a Petit's tourniquet is loosely applied above the wound, which the nurse is instructed to tighten up in the event of bleeding taking place.

Ligation of the Artery.—If the hæmorrhage recurs in spite of packing the wound, or if it is serious from the outset and likely to be critical if repeated, ligation of the artery itself or of the trunk from which it springs, at a selected spot higher up, should be considered. This is most often indicated in wounds of the extremities.

As examples of proximal ligation for secondary hæmorrhage may be cited ligation of the hypogastric artery for hæmorrhage in the buttock, of the common iliac for hæmorrhage in the thigh, of the brachial in the upper arm for hæmorrhage from the deep palmar arch, and of the posterior tibial behind the medial malleolus for hæmorrhage from the sole of the foot.