[Hospital infections with pseudomonas aeruginosa: I. Technical devices and wet areas as sources of infection in intensive care units (author's transl)].

In an intensive care unit system comprising three surgical intensive care wards bacteriologic investigations on the presence of Pseudomonas aeruginosa were carried out over a period of 7 months (as an example for the aetiology of hospital infections). Centers of contaminations were found to exist in wet areas and in technical devices (ultrasonic nebulizers, respirators etc.). In many cases, the bacterial strains isolated from patients were found by means of phage-typing to be identical with strains isolated from devices and wet areas. Additional experimental investigations showed the predominant role of ultrasonic nebulizers for germ dissemination. On the basis of the results obtained a patient oriented scheme of probable infection chains was tried to establish. Hereby the wet areas play a central role as reservoirs of germs and therapeutical devices as vectors. The results obtained were evaluated in order to define a catalogue of practical measures for interruption of infection chains.