Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-28T15:09:00.618Z Has data issue: false hasContentIssue false
  • English
  • Français

Bacterial Colonization in Humidifying Cascade Reservoirs After 24 and 48 Hours of Continuous Mechanical Ventilation

Published online by Cambridge University Press:  02 January 2015

Theresa A. Goularte ,
Marie Manning  and
Donald E. Craven
Theresa A. Goularte
Affiliation:
Department of Medicine, Boston University School of Medicine, Division of Infectious Diseases, Boston City Hospital, Boston, Massachusetts
Marie Manning
Affiliation:
Department of Medicine, Boston University School of Medicine, Division of Infectious Diseases, Boston City Hospital, Boston, Massachusetts
Donald E. Craven*
Affiliation:
Department of Medicine, Boston University School of Medicine, Division of Infectious Diseases, Boston City Hospital, Boston, Massachusetts
*
Hospital Epidemiology Section, Maxwell Finland Laboratory for Infectious Diseases, Boston City Hospital, Boston, MA 02118
Get access Rights & Permissions [Opens in a new window]

Abstract

We evaluated levels of bacterial colonization in the humidifying cascade reservoirs of 466 mechanical ventilators; 326 reservoirs were cultured after 24 hours and 140 were cultured after 48 hours of continuous mechanical ventilation. Bacterial colonization was absent in 284 (87.1%) of the humidifier reservoirs sampled at 24 hours and 125 (89.3%) of the reservoirs cultured at 48 hours. Levels of bacterial colonization in the remaining humidifiers were low (<100 organisms/mL). The median temperature recorded in the reservoir fluid of 30 different ventilators was 50°C (range 40° to 60°C). In vitro seeding of reservoir fluid at 50°C with 106 organisms/mL of four different species of nosocomial gram-negative bacilli and Staphylococcus aureus demonstrated rapid killing of all five strains over a 6-hour incubation period, and no significant bacterial aerosols were detected. Rates and levels of bacteria in heated humidifier reservoirs are low and nosocomial pathogens survive poorly at the median reservoir temperature of 50°C. We conclude that the heated humidifier reservoir on a mechanical ventilator is an unlikely source of colonization or bacterial aerosols, and therefore it can be changed every 48 hours with the ventilator tubing.

Type
Original Articles
Information
Infection Control & Hospital Epidemiology , Volume 8 , Issue 5 , May 1987 , pp. 200 - 203
Copyright
Copyright © The Society for Healthcare Epidemiology of America 1987

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Horan, TC, White, JW, Jarvis, WR: Nosocomial infection surveillance, 1984. MMWR 1986; 35:17SS–29SS.Google ScholarPubMed
2.Gross, PA, Neu, HC, Aswapokee, P, et al: Deaths from nosocomial infection; Experience in a university hospital and a community hospital. Am J Med 1980; 68:219–223.Google Scholar
3.Cross, AS, Roup, B: Role of respiratory assistance devices in endemic nosocomial pneumonia. Am J Med 1981; 70:681–685.CrossRefGoogle ScholarPubMed
4.Pierce, AK, Sanford, JP, Thomas, GD, et al: Long term evaluation of decontamination of inhalation-therapy equipment and the occurrence of necrotizing pneumonia. N Engl J Med 1970; 282:528–531.Google Scholar
5.Reinarz, JA, Pierce, AK, Mays, BB, et al: The potential role of inhalation therapy equipment in nosocomial pulmonary infection. J Clin Invest 1965; 44:831–839.Google Scholar
6.Craven, DE, Connolly, MG Jr, Lichtenberg, DA, et al: Contamination of mechanical ventilators with tubing changes every 24- or 48-hours. N Engl J Med 1982; 306:1505–1509.Google Scholar
7.Lareau, SC, Ryan, KJ, Deiner, CF: The relationship between frequency of ventilator circuit change and infectious hazard. Am Rev Respir Dis 1978; 118:493–496.Google Scholar
8.Simmons, BP, Wong, ES: Guideline for the prevention of nosocomial pneumonia. Infect Control 1982; 3:327–333.Google Scholar
9.Craven, DE, Kunches, LM, Kilinsky, V, et al: Risk factors for pneumonia in patients receiving mechanical ventilation. Am Rev Respir Dis 1986; 33:792–796.Google Scholar
10.Andersen, AA: New sampler for the collection, sizing, and enumeration of viable airborne particles. J Bacterial 1958; 76:471–484.Google Scholar
11.Rhame, FS, Striefel, A, McComb, C, et al: Bubbling humidifiers produce microaerosols which can carry bacteria. Infect Control 1986; 7:403–407.Google Scholar
12.Zuraleff, JJ, Yu, VL, Shonnard, JW, et al: Legionella pneumophila contamination of a hospital humidifier: Demonstration of aerosol transmission and subsequent subclinical infection in exposed guinea pigs. Am Rev Respir Dis 1983; 128:657–661.Google Scholar
13.Best, M, Yu, VL, Stout, J, et al: Legionellaceae in the hospital water supply: Epidemiologic link with disease and evaluation of a method for control of nosocomial Legionnaires' disease and Pittsburgh pneumonia agent. Lancet 1983; 2:307–310.Google Scholar
14.Craven, DE, Goularte, TA, Make, BJ: Contaminated condensate in mechanical ventilator tubing: A risk factor for nosocomial pneumonia? Am Rev Respir Dis 1984; 129:625–628.Google Scholar
15.Maclntyre, NR, Anderson, HR, Silver, RM, et al: Pulmonary function in mechanically-ventilated patients using 24-hour use of a hydroscopic condenser humidifier. Chest 1983; 84:560–564.Google Scholar
16.Heat and moisture exchangers. Health Devices Update. 1983;155–168.Google Scholar
17.Goularte, TA, Craven, DE: Results of a survey of infection control practices for respiratory therapy equipment. Infect Control 1986; 7:327–330.Google Scholar
18.Boyce, JM, White, RL, Spruill, EY, et al: Cost effective application of the CDC guidelines for prevention of nosocomial pneumonia. Am J Infect Control 1985; 13:228–232.Google Scholar
19.Lamb, VA, Mayhall, CG, Dalton, HP, et al: Pneumonia in patients on ventilatory support: Relationship to microbial flora of ventilator circuits. 25th Inter-science Conference on Antimicrobial Agents and Chemotherapy, Minneapolis, Minnesota, October 1985, (Abstract #446).Google Scholar