Sterile water used for humidification in low-flow oxygen therapy: it is necessary?

Currently it is standard practice in many acute care hospitals to use only sterile water in humidifier reservoirs for the delivery of low-flow oxygen therapy. This practice is based primarily on the Centers for Disease Control's 1982 "Guideline for the Prevention of Nosocomial Pneumonia." The present study was designed to investigate and compare the bacterial contamination of tap water and sterile water used to fill clean (nonsterile) disposable oxygen humidifier reservoirs. Disposable oxygen humidification reservoirs were assembled weekly according to standard protocol and regulated to deliver oxygen, 4 to 6 L/min, continuously for 5 consecutive days. Each of 48 reservoirs was filled with either tap water (24) or sterile water (24) and cultured daily. All disposable equipment was discarded after the final culture on the fifth day. An aliquot of water was obtained daily from each reservoir and plated to trypticase soy agar pour plates and to a matched trypticase soy broth. Bacterial growth was observed on trypticase soy agar pour plates from 54 (45.0%) of 120 sterile water reservoir cultures and from 38 (31.7%) of 120 tap water reservoir cultures (p greater than 0.05). Bacterial growth from the matched trypticase soy broth cultures was observed only from two sterile water reservoirs. The microorganisms identified from the sterile water reservoirs included Enterobacter agglomerans and Serratia and Bacillus spp. The use of tap water for low-flow oxygen humidification was determined to be safe at our hospital by the infection control committee. This procedural change contributed approximately $6000 to the cost reduction efforts of the respiratory therapy department.

California skilled nursing facilities.

It is estimated that of the 2.2 million people who turned 65 years of age in 1990, approximately 1 million will be cared for in a SNF at least once before they die (Satterfield, 1993). Under pressure from federal and state governments to reduce costs associated with acute care hospitalization, SNFs are admitting patients who require more complex medical and surgical care than in the past. Until recently, FS-SNF ICPs did not have the motivation to develop and implement complex infection prevention and control programs because their patients required a level of care that assured that their activities of daily living were met. In today's continuum of health care structure, SNFs are expected to maintain patients on ventilators and hyperalimentation and to care for patients recovering from complicated postsurgical procedures, such as total hip replacements and coronary artery bypass grafts. These patients are not expected to remain in SNFs until they die. They are expected to recover to their prehospitalization health status and, at a minimum, be discharged to the next lower level of care (i.e., board and care homes) or to assisted care in the family home. With the increased level of complex medical and surgical care that SNFs are now required to provide, infection prevention and control programs take on new emphasis. This is evidenced by the educational needs assessment reported by Leinbach and English (1995) and confirmed by this study. The basic principles of infection prevention and control are the same whether the patient is in a hospital, a DP-SNF, or a FS-SNF. However, the person responsible for infection prevention and control for a DP-SNF may be the same individual who is the ICP for the acute care hospital of which it is a part. Persons designated as ICPs for FS-SNFs often function in a much more isolated setting with limited access to resources. It is now time for experienced hospital-based ICPs to reach out to personnel in FS-SNFs to work together to develop and implement effective infection and prevention and control programs that meet the needs of patients cared for across the continuum.