title: Changing heat and moisture exchangers every 48 hours rather than 24 hours does not affect their efficacy and the incidence of nosocomial pneumonia.
abstract: Heat and moisture exchangers (HME) (Dar-Hygrobac II, Peters) can safely be used every 24 h for long-term mechanical ventilation and provide a cost-saving alternative to heated humidifiers. We have prospectively determined whether changing HMEs every 48 h only affects their clinical and bacteriological efficiency in a series of consecutive nonselected ICU patients requiring long-term mechanical ventilation. Two consecutive periods were compared. During period 1, HMEs were replaced every day; during period 2, they were changed every 48 h. Patients from the two periods were similar in terms of age and indication for and overall duration of MV (10 +/- 8.6 versus 10 +/- 9 d, p = 0.9). Minute ventilation and maximum values for peak airway pressure were identical during the two periods. These values were also identical after 1 and 2 d of HME use during period 2, indicating that HME resistance was not increased by prolonged use. Obstruction of the tracheal tube occurred only once in a period 1 patient. The results of quantitative cultures indicate that the maximum and mean levels of bacterial colonization during the two periods were similar for the pharynx, trachea, Y-connector, patient, and ventilator side of the HME. More importantly, the incidence of nosocomial pneumonia was similar during the two periods (6/61 versus 8/68, p = 0.7). Thus, prolonged HME use is safe and provides a substantial reduction in the cost of mechanical ventilation.
authors.affiliation: Service de Réanimation Médicale, Hôpital Louis Mourier, Colombes, France.
authors.forename: K
authors.initials: K
authors.lastname: Djedaini
authors.forename: M
authors.initials: M
authors.lastname: Billiard
authors.forename: L
authors.initials: L
authors.lastname: Mier
authors.forename: G
authors.initials: G
authors.lastname: Le Bourdelles
authors.forename: P
authors.initials: P
authors.lastname: Brun
authors.forename: P
authors.initials: P
authors.lastname: Markowicz
authors.forename: P
authors.initials: P
authors.lastname: Estagnasie
authors.forename: F
authors.initials: F
authors.lastname: Coste
authors.forename: Y
authors.initials: Y
authors.lastname: Boussougant
authors.forename: D
authors.initials: D
authors.lastname: Dreyfuss
mesh_terms: D000328:Adult; D000368:Aged; D003362:Cost-Benefit Analysis; D003428:Cross Infection / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control*; D004866:Equipment Contamination / Q000517:prevention & control / Q000706:statistics & numerical data; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control*; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000191:economics / Q000295:instrumentation* / Q000706:statistics & numerical data; D012449:Safety; D013997:Time Factors