[Contamination of respirators in long-term ventilation]

The role of artificial ventilation as an exogenous source of nosocomial pneumonia in long-term ventilated patients is well established. Hence, decontamination of respirators after use is inevitable, although this procedure is costly and time-consuming. The purpose of the study was to prove the efficacy of bacterial filters (Ultipor BB 50, Pall Ltd., Dreieich) in preventing microbial contamination of respirators during long-term ventilation. We investigated the impact of the patient tracheal flora on different parts of the ventilation system. A total of 30 patients included 9 patients treated with an aminoglycoside intratracheally and whose ventilators were equipped with breathing system filters, 10 patients treated with the aminoglycoside intratracheally and without filters, and finally 11 patients without antibiotic prophylaxis and without filters. 1495 samples were taken from different parts of the ventilation circuit. The data obtained suggest that there is no significant influence on the contamination rate of the ventilators by application of bacterial filters or intratracheal aminoglycoside. The use of the breathing system filters to protect the ventilator from microbial contamination, therefore, seems to be unnecessary.