Cryoprecipitate and the plastic blood-bag system: provision of adequate replacement therapy for routine treatment of haemophilia.

Abstract

In a survey of 210 young haemophiliacs living in South-east England it was recently shown that, by modern standards, under 20% received adequate treatment (Dormandy et al., 1967). The long-term management of the remainder fell short of what can and should be achieved even with the limited resources at present available to the hospital service. It was found, for example, that the potency of the frozen plasma issued at the time of the survey by the North London Blood Trans fusion Centre was often too low to be of any clinical benefit. This led to a comparative trial of plasma processed at the haemophilia centre of the Royal Free Hospital and at the trans fusion centre. At the same time a number of technical pro cedures were explored, particular attention being paid to the selection of those which could be widely adopted. After the report of Pool and Shannon (1965) cryoprecipitate rich in factor VIII was prepared ; 537 bags of this have been used in the trial since April 1966. In the course of the trial 239 infusions were given for 121 episodes of bleeding in patients with haemophilia. A further 23 infusions were given to patients with von Willebrand's disease. The results of the latter have been reported elsewhere (Bennett and Dormandy, 1966). A total of 1,304 pints (in 500 ml. units) of blood were used. The 914 pints which were collected by the plastic-bag method and processed at the haemophilia centre yielded 2,019 blood components, which were used separately. Supernatant plasma left after the separation of cryoprecipitate was given to three patients with Christmas disease (factor IX deficiency) and to one patient with plasma thromboplastin antecedent (factor XI) deficiency. Specific assays for factor IX and factor XI activity were carried out on these preparations.