Efficacy of portable filtration units in reducing aerosolized particles in the size range of Mycobacterium tuberculosis.

Objective: To evaluate engineering control measures to prevent nosocomial transmission of diseases such as tuberculosis, we studied four portable high-efficiency air filtration units, including three high-efficiency particulate air (HEPA) filtration units, for their ability to remove aerosolized particles.

Design: Studies were conducted in either a nonventilated aerosol chamber or in a hospital isolation room that met CDC guidelines for TB control (negative pressure, > or = 6 air changes per hour, air exhausted directly to the outside). The rooms were challenged with aerosolized mineral oil in the size range of 0.

FDA labeling requirements for disinfection of endoscopes: a counterpoint.

Endoscopes are used widely for the diagnosis and therapy of medical disorders. To prevent spread of nosocomial infection, all endoscopes should undergo thorough cleaning and high-level disinfection following each use. The Food and Drug Administration (FDA) has approved a user-friendly package label for one liquid chemical germicide that requires a 45-minute immersion at 25 degrees C to support a high-level disinfection label claim.

Management of healthcare workers exposed to pertussis.

The epidemiology of pertussis has changed in recent years. First, pertussis in adults is far more common than previously thought. Second, in many instances, the disease in adults is atypical or asymptomatic.

Sporicidal activity of chemical sterilants used in hospitals.

Objective: The current study was designed to assess the sporicidal activity of chemical sterilants using the Association of Official Analytical Chemists (AOAC) sporicidal test. Chemical sterilants are used most commonly in the healthcare setting to disinfect medical instruments such as endoscopes. This study was undertaken to evaluate the efficacy of several newer formulations of glutaraldehydes and hydrogen peroxide as chemical sterilants.

Evaluation of a rapid readout biological indicator for flash sterilization with three biological indicators and three chemical indicators.

Objective: Flash sterilization is most commonly used for emergency sterilization of unwrapped items in a gravity displacement sterilizer for three minutes. Sterilization quality assurance is monitored by biological indicators that require a 24-hour incubation prior to reading. In this study, we compared a new biological indicator that provides results within 60 minutes with three conventional, 24-hour biological indicators for monitoring flash sterilization and three chemical indicators.

Inactivation of Clostridium difficile spores by disinfectants.

Objective: The current study was designed to evaluate the activity of glutaraldehyde-based disinfectants against Clostridium difficile using the Association of Official Analytical Chemists' (AOAC) sporicidal test. This study was undertaken because gastrointestinal endoscopes that may be contaminated with C difficile spores are most commonly disinfected between patients using glutaraldehyde-based disinfectants.

Design: Using the AOAC test, the following disinfectants were tested: 2% alkaline glutaraldehyde, 2% acid glutaraldehyde, a 1:16 dilution of a 2% glutaraldehyde-7.

Relative frequency of nosocomial pathogens at a university hospital during the decade 1980 to 1989.

Background: We compared the relative frequency of pathogens isolated from 1985 to 1989 (N = 4358) with those isolated from 1980 to 1984 (N = 5290) in a university hospital to determine trends in the relative importance of pathogens causing nosocomial infection.

Methods: Our study was based on surveillance data prospectively obtained between 1980 and 1989 from a 600-bed university hospital. Statistically significant trends occurring from 1980 to 1984 to 1985 to 1989 were determined by chi 2 tests with Bonferroni corrections (i.

Transparent polyurethane film as an intravenous catheter dressing. A meta-analysis of the infection risks.

Objective: To obtain a quantitative estimate of the impact on infectious complications of using transparent dressings with intravenous catheters.

Data Sources: Meta-analysis of all studies published in the English literature, including abstracts, letters, and reports that examined the primary research question of infection risks associated with transparent compared with gauze dressings for use on central and peripheral venous catheters. Studies were identified by use of the MEDLINE database using the indexing terms occlusive dressings, transparent dressings, and infection and by review of referenced bibliographies.

Risk factors for nosocomial pneumonia in the elderly.

Purpose: Elderly patients have a disproportionate incidence of nosocomial pneumonia (NP) and a higher mortality rate, yet few studies have focused on this high-risk population. We undertook a study to examine risk factors for NP in elderly inpatients and to describe how these patients differ from younger patients with NP.

Methods: In a public teaching hospital, all cases of NP in patients aged 65+ were ascertained by prospective surveillance during a 2-year period (n = 59).

Inactivation of Mycobacterium tuberculosis and Mycobacterium bovis by 14 hospital disinfectants.

Epidemics of mycobacteria due to contamination of medical devices continue to occur. For this reason, we assessed the ability of disinfectants, generally used in hospitals for disinfecting noncritical and semicritical patient care items, to inactivate mycobacteria. A modified Association of Official Analytical Chemists' (AOAC) Tuberculocidal Activity Test, using Middlebrook 7H9 broth as the primary subculture medium and neutralization by dilution, was used to assess the ability of 14 hospital disinfectants to inactivate about 10(6) Mycobacterium tuberculosis and about 10(5) Mycobacterium bovis at 20 degrees C using 10- or 20-minute exposure.

Nosocomial infection rate as a function of human immunodeficiency virus type 1 status in hemophiliacs.

As part of a prospective cohort study initiated in 1983, the human immunodeficiency virus type 1 (HIV-1) status has been periodically determined for patients with clotting disorders (hemophilia A or B, von Willebrand's disease, miscellaneous). The University of North Carolina Hospitals has conducted comprehensive surveillance for nosocomial infections (NI) using modified Centers for Disease Control criteria since 1980 and entered this information in a computerized data base. Cross-matching of our NI data base and hemophiliac/HIV-1 study data base for the time period 1980-1989 revealed that 13 NI occurred in 11 patients during 659 hospitalizations (5,723 hospital days).

Gas and steam sterilization of assembled versus disassembled laparoscopic equipment. Microbiologic studies.

Current recommendations specify disassembly of most laparoscopic equipment prior to sterilization. Surgical technicians, however, are often unfamiliar with the proper assembly of laparoscopic instruments, resulting in possible patient injury from equipment malfunction. Therefore, we tested the hypothesis that disassembled laparoscopic equipment is sterilized more thoroughly than assembled equipment.

Disinfection and flash sterilization in the operating room.

Items that enter sterile tissue or the vascular system are considered critical items and must be sterile. Semicritical items are those objects that come in contact with mucous membranes or with skin that is not intact; they require high-level disinfection. Noncritical items come in contact with intact skin and require low-level disinfection.

Disinfection practices for endoscopes and other semicritical items.

Objective: To determine the disinfection practices employed by North Carolina hospitals for endoscopes and other semicritical patient care items and to discuss minimally acceptable disinfection procedures for these items.

Design: A survey questionnaire was mailed to all North Carolina hospitals to identify their disinfection practices, and a literature review was conducted to ascertain studies that evaluated disinfection techniques for certain semicritical items.

Participants: Questionnaires were returned by 107 of 167 (64%) North Carolina acute-care hospitals.

Infection control strategies relevant to employee health.

A well organized employee health service is a key component of an effective infection control program. All health care providers should be immune to mumps, measles, rubella, tetanus, and polio. Hepatitis B vaccine should be offered to all workers who have contact with blood.

Infection risks associated with spirometry.

Objectives: Spirometry is a widely used pulmonary function test that allows measurement of forced vital capacity and time-related measures of dynamic pulmonary function. This study was designed to identify the risk of cross-transmission associated with two commonly used dryrolling seal spirometers.

Design: Using a prospective study design, we examined whether microbial contamination of spirometers occurred following use by patients with a heavily colonized or infected respiratory tract.