Greater success is claimed by Hooker, who reported that in five cases of pyogenic infection the results were distinctly favourable. He used immunized blood, but has formed the impression that the transfusion even of normal blood is of value in septicæmia by correcting the anæmia and helping to restore the normal resistance. He recommends that if the patient has a good blood volume and a high bacterial content in the blood, he should be bled by venesection before transfusion. A striking case of staphylococcal septicæmia has been recorded by Little, who believed that the patient’s recovery was directly due to the treatment. Four transfusions were given, the blood for three of these being taken from donors who had each received, four days previously, an injection of vaccine made from the patient’s own infection. Ottenberg and Libmann have treated ten cases of pyogenic infections with transfusions. All the patients were extremely ill and six died. It is stated that the four who recovered “probably owe their lives to the transfusion,” but obviously it is difficult to control the results. The same observers have used transfusion in the treatment of infective endocarditis, but unsuccessfully.

Some experimental work on this subject has been carried out by Kahn. A bacterial infection was introduced into the peritoneal cavities of several dogs. Continuous transfusion between an infected dog and a healthy dog was then performed, the blood passing to and fro between the animals, sometimes for over an hour. It was found that all the transfused animals fared better than those that were not. The experiment suggests that resistance to infection is heightened if two bodies can combat the infection present in one; but continuous transfusion is scarcely practicable in man.

Diphtheria.—In the later stages of some acute diseases due to a bacterial infection, the patient falls into a condition of acute toxæmia, the symptoms of which resemble in some ways those of shock. Harding has drawn attention to this condition in diphtheria; he has produced it experimentally in animals and has treated it by blood transfusion. The toxæmic stage was found to occur on the fourth to the eleventh day. It was characterized by a reduction of the output of the heart with a corresponding fall in blood pressure, an exudation of lymph into the tissues, and an increased specific gravity of the blood. In all these respects it resembled the collapse due to trauma or to hæmorrhage, and it was shown by experiment that the treatment must be directed towards increasing the amount of effective fluid in the circulation and to decreasing its viscosity. It was found that normal saline solution failed to do this; gum-saline solution also failed, and tended to produce a pronounced agglutination of the red blood cells. Blood transfusion, on the other hand, resulted in a considerable number of recoveries. In the aggregate more than twice as many animals survived after transfusion as survived without it, the same amount of toxin being given in each case.

These experimental findings are exceedingly suggestive, but the clinical efficacy of the treatment still remains to be proved. Harding found that the amount of blood that should be transfused was one-fifth of the total blood volume; the following amounts are, therefore, recommended for the treatment of children in the toxæmia stage of diphtheria:

Age.Weight.Amount.
1½ years.21 lbs.160 ccm.
2 ”28 ”200 ”
4 ”35 ”300 ”
6 ”42 ”400 ”

Pneumonia.—A condition of toxæmia similar to that seen in diphtheria was also observed in some of the cases of pneumonia which complicated the influenza epidemic of 1918-19. In the United States, among a large number of cases admitted to an emergency hospital, a series of 28 patients, some of whom were moribund, was treated by blood transfusion by Rose and Hund. The results were compared with those in 21 similar cases which were not transfused. The figures seemed to show that transfusion was of some value. Of the 28 who were transfused, 6, or 22·4 per cent., died, and the rest recovered; of the 21 who were not transfused, 9, or 47·7 per cent., died, and 12 recovered. The numbers treated are not large enough to afford statistical evidence that can be relied upon, but the results were at least encouraging.

Typhoid, Measles, Tuberculosis.—Transfusion has been tried for several other bacterial infections with varying results. McClure has administered immunized blood to a typhoid patient with a remarkably good result. Ottenberg and Libmann have transfused five typhoid patients, all of whom were desperately ill; two of them recovered. Transfusion has also been used for intestinal hæmorrhage in typhoid, but this is chiefly with the object of combating anæmia. Subcutaneous injection of blood has been successfully used by Terrien in a case of malignant measles; the donor had had measles six months previously. Freilich has recently transfused six patients suffering from tuberculosis, but without benefit. He is at present testing the use of blood from donors who show a positive complement fixation test for the tubercle bacillus.

It is evident that treatment with immunized blood is still in an experimental stage, but it merits further trials, all the circumstances of which should be carefully recorded.

Toxæmias of Pregnancy.—The treatment of eclampsia by blood transfusion was first employed by Kimpton, who speaks favourably of the results obtained. Later it was independently suggested to Blair Bell, who was the first to employ it in this country, by certain investigations into the facts of immunology. It had been found that symptoms resembling those of eclampsia could be produced in mice by injecting into them an extract of placenta, whether from a healthy or an eclamptic woman; the same results were obtained by injecting fresh serum from similar individuals. Further, if the placental extract was mixed with serum from a normal person of either sex, the effects were not obtained, and it was inferred that the placental toxin had been neutralized by antibodies in the serum. If, however, the placental extract was mixed with serum obtained from the blood of an eclamptic patient, then the toxic symptoms were obtained as before. Apparently, therefore, the serum in eclampsia lacks certain antibodies which are present in the serum of normal individuals. If these observations had been correctly interpreted, it seemed reasonable to suppose that blood from a normal person would supply an eclamptic patient with the antibodies which she lacks. The patient treated by Blair Bell was already comatose and apparently dying. She was given 500 cc. of citrated blood and rapidly recovered; her convalescence was uninterrupted. It would be unwise to found great hopes on a single case, but the treatment undoubtedly merits further trial.

Transfusion has also been used by Keator in treating the toxæmia of early pregnancy, and Morel has successfully used the blood of a healthy pregnant woman for the same purpose. Gettler recommends the use of alkalinized blood for “acidosis” in pregnancy. At present, however, little evidence can be adduced in favour of this form of treatment.