Some of the concluding remarks in the foregoing pages will have suggested that the use of gum infusion may be considered of more value in treating pure shock than in treating hæmorrhage. For this reason, apart from other diagnostic considerations, it may be of importance to be able to distinguish clinically between shock and hæmorrhage. Attention has already been drawn to the fact that the symptoms and appearance seen in a patient suffering from severe shock very closely resemble those seen in hæmorrhage. It may, in fact, be impossible to say from purely clinical evidence whether a patient is suffering from shock, or hæmorrhage, or both. A case which recently came under my own observation well illustrates this point. A very stout, elderly man had fallen down a lift-shaft and was brought into St. Bartholomew’s Hospital soon after the accident. He appeared to have fallen on his feet, and the lower ends of both tibiæ had been driven through the inner sides of his soles, but there were no other signs of injury. His general condition on arrival at hospital was fairly good, but all the usual measures were taken to minimize shock. An hour or two later he had passed into a condition of extreme collapse, and exhibited all the symptoms which have already been described. Not much hæmorrhage had taken place from the wounds in his feet, and the question arose as to whether his present condition was due to internal hæmorrhage from visceral injury, or whether it was due chiefly to shock. His abdomen contained so much fat that no evidence could be obtained from an examination of it, and it was in fact impossible to arrive at any conclusion. There could, however, be no question of performing any operation, and the patient made no response to other treatment. At the autopsy it was found that there were fractures of the ribs, spinal column, and symphysis pubis in addition to the injuries to the legs. There was very little hæmorrhage in connexion with any of the fractures, and it appeared that death was to be attributed almost entirely to shock. This was perhaps a somewhat unusual case, in which no help could be derived from an examination of the patient, but similar difficulties will sometimes be met.
It might be expected that a criterion would be supplied by an examination of the blood. The results from this, however, have proved to be disappointing. The facts have been investigated by Cannon and others (47) and may be summarized as follows. The number of red corpuscles in the blood from the capillaries of the ear or finger has been found to be invariably raised in patients suffering from shock. A blood count may show an increase up to seven million red cells per cmm. or even more. The blood in the venous circulation, however, of the same patient is more dilute, the count being less by one to two million red cells. When the shock is complicated by hæmorrhage, the blood count in the venous system will again be lower than that in the capillaries, but in both the counts will be less than if there were no hæmorrhage. The differences are, however, not so great or so constant that any principle can be laid down by which the two conditions may be distinguished. In patients in whom hæmorrhage is the outstanding feature the blood counts will be still lower, but the capillary and venous difference will still be present. It was found that in hæmorrhage the hæmoglobin percentage, and therefore the colour index, tended to be lower than in shock, but this was most obvious when the hæmorrhage had been very severe, and in such cases the diagnosis is usually clear from other evidences. The clinical difficulty lies in the distinction between cases of pure shock and of shock complicated by considerable hæmorrhage. It seems that little help is to be derived from an examination of the blood. This difficulty in diagnosis can only influence treatment in the direction of giving blood rather than gum-saline, though the latter would probably be effective for many of the cases of shock if they could be distinguished.
The effects of transfusion for hæmorrhage and shock are to be judged best by the clinical results. The abnormal distribution of the corpuscles is altered by the treatment with a consequent redistribution in the circulation. No constant changes, therefore, in the blood count follow transfusion, and no exact mathematical effect can be demonstrated. It has been shown by Huck that sometimes the immediate rise in the blood count is greater than can be accounted for by the amount of blood given. This is often followed by a fall, which is succeeded in its turn by a second rise. These results are to be explained by alterations in the amount of destruction and formation of red cells going on in the body. That is to say, they are biological rather than mechanical, and are at present but imperfectly understood.
In the foregoing discussion hæmorrhage and shock have been considered in a general way. Something must now be said of the particular conditions for which transfusion may be given. Concerning traumatic hæmorrhage and shock there is little to be added, for these conditions present the general features of the problem in its least complicated form. No clear-cut rule can be laid down as to the point at which transfusion becomes necessary. The blood pressure is perhaps the best single indication, and if this has fallen below 80 mm. (systolic), then a transfusion is certainly indicated. Apart from this, the patient’s general condition is the safest guide. As soon as it becomes evident that his life is in danger, a transfusion should be given. Better save a few lives by many transfusions than lose them by reserving transfusion for those who are actually moribund.
Secondary hæmorrhage following an operation is fundamentally similar to primary hæmorrhage, but may present a few additional points. In recent years by far the largest number of transfusions for secondary hæmorrhage have been given for bleeding from septic amputation stumps. In many cases of this sort it is no easy matter to stop the bleeding by ligaturing a bleeding vessel; sometimes it is impossible. Nevertheless, transfusion should not be withheld owing to a risk of increased hæmorrhage supposed to follow a rise in blood pressure. Usually the patient is debilitated by prolonged suppuration, and often his blood is deficient in its power of coagulation. It has been found that a transfusion, in addition to replacing some of the blood that has been lost, tends to improve the patient’s resistance to micro-organisms, and to shorten the coagulation time of the blood. Recurrence of the hæmorrhage is therefore discouraged on the whole, and in many cases a series of transfusions for recurrent hæmorrhages has saved a patient’s life when the prognosis had seemed to be almost hopeless.
Post-operative hæmorrhage associated with chronic jaundice is another condition which demands special consideration; this will be dealt with later under the heading of hæmorrhagic diseases.
The proper treatment of severe hæmorrhage from a gastric or duodenal ulcer has always puzzled physicians and surgeons alike. It is probably true that patients very seldom die as the result of a single rapid hæmorrhage, even if severe. There can, however, be no doubt that death due actually to acute anæmia may follow repeated or prolonged hæmorrhage. Hitherto treatment has been conducted mainly on medical lines. Opinion is now, however, tending to favour earlier and more frequent surgical interference, and this can be made a less dangerous procedure by giving a preliminary blood transfusion to improve the patient’s general condition. When the patient’s life is threatened by hæmorrhage repeated or prolonged, transfusion is undoubtedly the best means of saving him. Here again the fear of restarting the hæmorrhage by raising the blood pressure has acted as a deterrent, so that transfusion is apt to be withheld until too late. Nevertheless, it is clear from the numerous cases recorded in the literature that this fear is groundless (130, 215, etc.). The effect of a transfusion on the coagulating power of the patient’s blood more than compensates for the risk attending a rise in blood pressure. Now only is lost blood replaced, but also the clot plugging the damaged vessel is made more secure. The patient is tided over the immediate danger to his life, and surgical treatment is made possible. This view will doubtless meet with much adverse criticism, but its justice will eventually be recognized.
As in the early days of transfusion, so at the present time, a considerable proportion of the patients that need transfusion will be met with in the course of obstetrical practice. It has often been remarked how much blood can be lost by a woman following the delivery of her child without any serious result; nevertheless, many deaths are occasioned every year by post-partum hæmorrhage, placenta prævia, and rupture of an ectopic gestation. Sometimes the bleeding is so rapid that there is no margin of time available for a transfusion unless all the facilities be immediately at hand. Short of this, transfusion is the ideal treatment, and the problem is a simple one, the relief of acute anæmia being the only object in view. One interesting modification of the procedure has been recently recommended by German writers, namely, the reinfusion of the patient’s own blood. This is applicable only when the hæmorrhage has taken place into the peritoneal cavity, and is therefore limited to the treatment of a ruptured liver or spleen, a ruptured uterus, or a tubal abortion. With a ruptured uterus the sterility of the blood is not assured, and this condition were better not included. For the other conditions Lichtenstein recommends that the blood should be ladled out of the peritoneal cavity into Ringer’s solution and then strained to remove clots. The resulting fluid is infused into a vein. Judging from my own experience of intraperitoneal hæmorrhage, not much blood would actually be recovered in this way, since usually so much of it has clotted. In any case, the whole procedure is to be looked upon with suspicion owing to the unknown and probably profound changes that have taken place in partially clotted blood. Eberle records that in one case reinfusion was followed by hæmolysis, and among twenty-one cases reported by Schweitzer in 1921, one death was attributed to the reinfusion, which, as in Eberle’s case, was followed by hæmoglobinuria. Transfusion has also been used for the toxæmias of pregnancy, but this will be dealt with under another heading.