ABSTRACT
Transmission of hepatitis C virus between hemodialysis patients occurs mainly between the patients treated simultaneously in the same sector or in the same room. The other mode of viral transmission occurs between two patients treated successively with the same hemodialysis generator-monitor and sharing the same environment. One of the vectors of this last mode of transmission could be the contamination of the system of measurement of pressure of the extracorporal blood circuit. In July 2004, the French health products safety agency (Agence française de sécurité sanitaire des produits de santé, Afssaps) published a recommendation on these systems of measurement of pressure. i) The recommendation points out the optional preventive measures that users and manufacturers can carry out: (a) the manufacturers can propose tight systems of measurement of pressure, based on the deformation of a device; (b) the users can add a second protective filter on the external tubing connecting the blood circuit to the machine; (c) the manufacturers can add additional protective filters on the internal tubings of the machine. ii)The recommendation indicates the actions to be carried out obligatorily in the event of backward flow of blood in the last external protective filter: the soiled filter must be replaced and the causes of the backward flow must be analyzed and corrected; after the session, the monitor must be taken out of the unit and checked by a technician. The technician must replace all the elements located downstream from a soiled protective filter: tubings, drip chamber level control system, and pressure transducer. When these elements are protected by internal filters, only tubings and the first internal filter not soiled must be replaced. Precautions with regard to the systems of measurement of pressure must supplement standard precautions of hygiene essential in hemodialysis units.