[Hygienic and bacteriological comparative studies in 50 hospitals. IV. The bacterial contamination of fluids of intensiv care units, wards for premature children and new-born wards (author's transl)].

In intensive-care units and wards for prematures frequent use is made of medical apparatuses (such as oxygenators, nebulizers, respirators and incubators). These units are provided with a water reservoir which is utilized for the humidifications of the inspiratory air. They have become indispensable tools, especially in the treatment of seriously-ill patients. However, the water reservoirs of these devices have also frequently been found to harbour sometimes high concentrations of pathogens. With a view to clarifying the question as to the extent that liquids of different origin in the hospital area are contaminated with bacteria, 323 liquid samples were collected from intensive-care units, wards for premature and for newborn babies, and submitted for analysis. The senior nurse was questioned to obtain information about the measures of disinfection adopted in the respective wards. It was possible to cultivate pathogens from 22 per cent of the samples. P. aeruginosa accounted for 46 per cent, Enterobacter for 17.6% and E. coli for 12 per cent. A breakdown of the liquids by origin gives the following picture: 30 per cent of the liquids used for humidification of the inspiratory air (from respirators, inhalers etc.) were contaminated with pathogens. The analysis yielded a similar result in about 47 per cent of the cleaning water samples, in 10 per cent of the solutions in which clinical thermometers are kept and in 0 per cent of liquids from containers in which dressing forceps are kept. It emerged from inquiries that the lack of knowledge about the proper implementation of disinfection measures on the part of the nursing staff is still considerable. As a result, disinfectants of the quarternary ammonium compounds were used for the disinfection of medical apparatus in 37 per cent of all applications although their bactericidal action on gram-negative bacteria is limited. As regards the antimicrobial treatment of such parts as nebulizer chambers, connecting tubes, reservoirs of ultrasonic nebulizers, oxygen bottles and respiratory, parts with which the patient does not come into direct contact - the possibility of sterilizing them by autoclaving should be examined first. Not until this procedure has been ruled out on account of the thermolability of the materials used should another procedure such as keeping the materials in a disinfecting solution be adopted.