Hereditary haemophilia : deficiency in the coagulability of the blood the only immediate cause of the condition / by Thomas Addis.

  • Addis, Thomas, 1881-1949.
Date:
1910
Catalogue details

Licence: In copyright

Credit: Hereditary haemophilia : deficiency in the coagulability of the blood the only immediate cause of the condition / by Thomas Addis. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    formed elements of the blood when they are injured. But even though the sealing-off of thrombokinase is not absolute, the blood may take a very long time to coagulate, even if the flow of fresh blood from the vessels has been stopped by the secondary coagulum. With minimal amounts of thrombokinase the coagu- lation of haemophilic blood may take many hours to complete itself. If, during this period, the secondary coagulum is dislodged from the mouths of the vessels, by, for instance, a sudden rise of blood pressure, the bleeding will recur, and— since the access of large amounts of thrombokinase from the tissues is prevented by the peripheral primary layer of clot—may continue indefinitely. This explanation of the reason for the continuance of bleeding in haemo- philia in spite of the occurrence of coagulation in the wound was suggested by observations made on a haematoma which developed in Case IV. Some puncture wounds rather deeper than usual had been made into the extensor surface of the right thumb, in order to collect some blood from which to obtain serum. Bleed- ing ceased almost immediately, but three-quarters of an hour later, while he was washing his hands in hot water, quite brisk haemorrhage started from one of these wounds. It was apparent then that the stopping of the bleeding soon after the wound had been made had not been due to coagulation. It must rather be attributed to the elasticity of the skin, which by its recoil led to the close apposition of the lips of the wound and so to a mechanical prevention of further loss of blood. For when the skin was relaxed by hot water the wound opened and bleeding began again. Some cotton-wool steeped in freshly shed normal blood was applied and pressure exerted by a bandage. No blood soaked through, but when, three hours later, it was taken off, bleeding began again. Two estimations of the coagulability of the blood streaming from the puncture gave times of 48 min. and 49 min. Pressure again stopped the bleeding until an hour and a half later, when he took a hot bath. Shortly afterwards he came to me because blood was coming through the bandage. Blood was flowing freely, and whenever the lips of the wound were separated, a jet of blood spurted out, indicating that a small arteriole had been cut. The coagulation times of three specimens of blood from the wound were 43 min., 61 min., and 51 min. Now it was inconceivable that after all these hours there had not been ample time for the blood remaining in the wound to completely coagulate if it was in contact with the tissues and thus taking up large quantities of throm- bokinase from them. In Case III, as has been shown, complete coagulation in the wound took place in twelve minutes. The only explanation appeared to be that in this case complete coagulation had only occurred locally. Only the film of blood in direct contact with the tissues, in which therefore the concentra- tion of thrombokinase was high, had clotted. The amount of thrombin set free from this primary coagulation had not been sufficient to completely coagulate the blood in the centre. A small pool of partially coagulated blood wa3 left there in communication with the cut vessel and cut off from the tissues, and therefore from the access of thrombokinase by the peripheral primary clot. When the wound opened, this central blood was washed out and the flow