C. Hon, A. Yassi, OHSAH, Vancouver, BC, Canada.
Severe Acute Respiratory Syndrome (SARS) is a novel disease that garnered international attention in early 2003. Although Vancouver only had a handful of probable SARS cases, the level of fear and anxiety surrounding SARS in Vancouver cannot be understated. When it became apparent that symptomatic patients could transmit the virus to health care workers, there was considerable concern and a call for the immediate implementation of protective measures. This case study describes the occupational hygiene principles applied in the province to help minimize the transmission of this disease to health care workers. Some of the problems were:
A pragmatic way of tackling this emerging issue was a collaborative science-based approach. This consisted of the establishment of a Provincial SARS Science Committee with representatives from a variety of disciplines including occupational hygiene. The committee developed “Guidelines for the Acute Management of the Patient with SARS in the Hospital Setting.” The Guidelines included a risk assessment table which outlined the various levels of risk and the corresponding protective equipment to be used. An educational working group was spun off from the provincial committee. The purpose of this working group was to develop a train-the-trainer session, which would teach participants about infection control, risk assessment, exposure control measures, respirator fit-testing, and proper donning and doffing of personal protective equipment. This training was reviewed by key stakeholders and provided free of charge to health care facilities and was facilitated by hygienists and infection control practitioners.
S. Yu, J. Kwan, Hong Kong University of Science and Technology, Hong Kong, Hong Kong Special Administrative Region of China.
The primary focus of infection control has always been protecting patients from nosocomial infection. Some patient-care practices and facility features also protect health care workers (HCWs). There are other staff protection measures such as vaccination and personal protective equipment (PPE). This aspect of an infection control program is clearly an occupational hygiene (OH), and in particular, biological safety issue. Conventionally, however, direct inputs from OH professionals appeared to be limited.
The significant infection rate among HCWs during the Spring 2003 SARS outbreak drew serious attention to the HCW protection issue. There are at least three areas where OH professionals may contribute to better protecting HCWs from newly emerged infectious diseases such as SARS. The first is hazard control principles. Existing isolation practice calls for housing infectious patients in isolation wards with special ventilation, such as negative pressure and increased air change. Even though HCWs don PPE while working inside the ward, infectious bioaerosols are allowed to move freely within the unit, and both personnel and articles in the ward are at risk of exposure or contamination. The concept of control at source through local exhaust ventilation may significantly enhance the current practice.
OH inputs regarding biological hazard control measures is the second area that may benefit the practice of infection control. The SARS outbreak revealed a common misconception about the effectiveness of high efficiency particulate air filter against small particles such as the SARS coronavirus. This led to unnecessary difficulties in designing control measures, and wastage of resources. The third area of input is proper use of PPE. Factors such as selection, fitting, training, disinfection, donning, and removal will all affect the effectiveness of PPE. Cases of SARS infection of HCWs who were ostensibly protected by PPE illustrated the ineffectiveness and danger of over-relying on PPE, particularly when necessary training is missing.
J. Kwan, S. Yu, Safety and Environmental Protection Office, Hong Kong University of Science and Technology, Kowloon, Hong Kong Special Administrative Region of China.
The global outbreak of Severe Acute Respiratory Symptoms (SARS) in Spring 2003 brought into focus the importance of controlling bioaerosols for the protection of both patients and workers in a health care environment. Although it is well-known that control measures at the source are the most effective, conventional infection control practices only provide for isolation wards and personal protective equipment for health care workers. This presentation describes a series of portable/mobile local exhaust ventilation devices for the capture, containment, and removal of bioaerosols immediately after they are released from individuals suffering from respiratory infections. These devices further focus the practice of source control to the breathing zone of patients, and thereby significantly increase protection of health care workers in the vicinity.
These devices utilize the well-established bioaerosol control measure of high efficiency particulate air (HEPA) filter or ultra low penetration air (ULPA) filter, and are leak-tested according to National Sanitation Foundation (NSF) guidelines. Each system is comprised of a capturing device which is designed for close capture and containment at source, connecting ducting, a HEPA or ULPA filter, and a blower. These devices are designed to be used during transport of patients on wheelchair or gurney, while in transit in ambulance, during confinement in bed, and while undergoing high-risk medical procedures such as intubation, resuscitation, bronchoscopy, sputum induction, nebulizer treatment, etc. The headpiece and tent are either designed to be disposable or can be disinfected. The filter and fan unit can be fumigated using the same principles for disinfecting biological safety cabinets, and following the relevant NSF guidelines. Some of these devices are already being used in hospitals and government clinics in Hong Kong.
J. Benyo, R. Rosenbaum, D. Williams, B. Humphrey, B. Passarello, J. Berry, J. Krebs, D. Parker, R. O’Conner, Christiana Care Health System, Newark, DE.
Treatment of patients with communicable diseases via the respiratory route may necessitate respiratory isolation precautions. This is usually accomplished in a single patient room with negative air pressure and a separate ventilation system from the rest of the hospital. The risk of a bioterrorism event with a transmissible pathogen such as smallpox or plague or a naturally occurring outbreak of influenza or SARS has increased the need to develop a greater capacity for this type of room.
Respiratory isolation rooms are generally few in number and expensive to construct. This results in a limited number of beds available for this type of patient. Many times they are located within inner areas of the hospital necessitating the transport of the respiratory isolation patient through the hospital, thus potentially exposing visitors, staff, and other patients.
The solution to this problem was to create a large isolation area that allowed the respiratory isolation patients to be cohorted. This was accomplished through the use of four portable forced air HEPA filtration machines in a physical therapy gym. The gym encompasses 2930 square feet and would allow the cohorting of approximately 30 patients. Each HEPA machine exhausted approximately 200 cubic feet per minute. A pre-fabricated plywood insert was made for one of the exits and the exhausts from the four HEPA machines were connected to the insert. Six workers were able to complete set up in approximately one hour. A total of 16.4 air changes per hour was achieved using all four machines on the high setting. The CDC guideline for airborne isolation areas is 12 air changes per hour.
This project provided a significant increase in isolation capacity within a short period of time and without incurring significant costs. Total cost of this project was less than $3000.00.
Z. Zhou, C. Jiang, J. He, Guangzhou No.12 Hospital, Guangzhou, China.
Purpose: To study the environmental and occupational hygiene factors in SARS outbreak.
Methods: Time series of meteorological elements were analyzed to understand the environmental conditions around SARS outbreak. Clinic infection cases and success stories in infection prevention were collected and reviewed from an occupational hygiene angle.
Results: Low wind speeds, big fluctuations of air temperature and pressure, increased cloudiness, lower humidity, and higher concentrations of airborne particulate were recorded around SARS outbreak. All clinic infections can be attributed to problems in the five key links of occupational hygiene: risk recognition/identification, risk assessment, risk communication, risk control/protection, and risk management. In the early stage of the epidemic, facing a new disease, people did not recognize or ignore that something unknown itself was a potential hazard. Given a disease with similar symptoms to those of other respiratory illnesses, it was hard to make strict criteria to diagnose (identify) SARS victims, incuring inter-infection in hospitals. Problems in risk communication were manifested by no epidemic report network and insufficient communication among hospitals. The follow-up and concentrated isolation of virus carriers thus became difficult. Uncertainty in patients’ number and the course and infection ways of the disease increased the difficulty of risk assessment. Lacking information from these three links, medical personnel were exposed to the hazard (SARS patients) without effective PPE and other control measures. Finally, poor risk management such as wrong layout, unsafe handling of patients’ excrements, unreasonable treatment processes, overstrain of medical staff, also aggravated the epidemic situation. In contrast, those health-care facilities without serious clinic infection had success stories in most of the links.
Conclusions: Biological factor was the offender of SARS. Environmental conditions contributed to the outbreak of the epidemic. Occupational hygiene in health care institutions is key to the control and prevention of SARS.
J. Dement, L. Pompeii, C. Epling, T. Ostbye, H. Lipscomb, Duke University Medical Center, Durham, NC.
This paper outlines the development and implementation of a comprehensive occupational safety and health surveillance system for health care workers within the Duke University Health System (DUHS). The system tracks occupational exposures and stressors, injuries and illnesses, as well as their causes and consequences, among a defined population of health care workers. Human resources job and work location data were used to define the population at risk within the DUHS. Additional data collected from existing occupational health and safety programs, employee health insurance claims, and health risk appraisals were linked with human resources data to create a comprehensive surveillance system.
Application of the system for surveillance and etiologic analyses of blood and body fluid (BBF) exposures is presented. For analyses of BBF exposures, the population at risk, worker demographics, and time at risk were defined using human resources data. Over 2600 BBF cases occurring during 1998–2002 were identified through linkage with the Duke BBF reporting system and workers’ compensation data. For the most recent year (2002), needlestick injuries (n = 327) were the most common among the 554 BBF exposures reported, followed by splashes to the face (n = 105), sharp injuries (n = 91), and bites/non-intact skin (n = 31). Operating room staff reported the greatest number of exposures, followed by surgical and medical intensive care staff. Overall, nursing personnel, followed by physicians, were among the most frequent occupational groups to report an exposure. Employing both stratified analyses and Poisson regression, rates of BBF exposures (cases per 100 FTEs) were significantly elevated among surgical and operating room personnel with highest rates for OB-GYN house staff. Use of these data and the surveillance system for development and evaluation of prevention programs is discussed.
T. Havel, T. Millon, Kaiser Permanente Hospitals, Pasadena, CA; N. Lal, Kaiser Permanente Hospitals, Oakland, CA.
Lift team intervention programs are designed to reduce the risk of ergonomic-related injury of patient care services (PCS) staff due to the handling of dependent patients. Lift teams were first introduced at Kaiser Permanente in the year 2000 as pilot interventions in 7 of the 28 California-area hospitals. Two years after implementation, Kaiser Permanente surveyed these pilot interventions to promote best practice sharing within the organization. The survey factored over 40 lift team program elements and compared them to injury rate reductions in targeted work environments specific to the medical center represented by the survey results. The purpose of this survey was to identify critical lift team success factors in reducing workplace patient handling injuries. These success factors included both the challenges (e.g. department sponsorship and communications with staff) and innovation of technique. Four success factors were derived from the survey as optimal in the reduction of patient handling injuries. These critical success factors include: (1) enforcement of lift team policies/guidelines, (2) lift team technicians working in pairs throughout the shift, (3) full utilization of patient handling equipment, and (4) training of PCS staff in “team lift” approach and patient handling equipment utilization when the lift team is unavailable. These critical success factors were emphasized in the development and guided the 2002 roll out of lift team programs in 20 additional California region hospitals. After a year of lift team intervention, targeted areas have resulted in a 46% reduction in injury reporting rates related to patient handling in the targeted in-patient acute care work environments. As a result of the success, lift team programs are now being expanded in these hospitals to cover additional shifts and outpatient care work environments.
G. Ganson, Terracon, Lenexa, KS; J. Romine, Brack & Associates Consulting Engineers, Topeka, KS.
Because surgery rooms require an exceptionally clean environment to prevent exposure to infectious agents, operating room ventilation systems must be capable of delivering conditioned air that is free from recognized human pathogens. A Midwest town recently added a new surgery wing with 20 surgical suites to one of its largest hospitals. The first challenge was to design and install a state-of-the-art ventilation system that would reduce airborne particulates in each of the operating rooms and reduce dispersal of aerosolized infectious materials. Two high volume air-handling units were installed using a three-stage filtration system located in the air handler and a laminar flow delivery system in each operating room. The third filter in each unit was a high efficiency, particulate air filter.
Prior to commissioning the new surgery wing, the hospital requested an evaluation of the filtration system. The challenge was to devise a method that provided information on filter effectiveness. Particulate counting was selected as the method that would provide immediate results and quantify measurement of filter effectiveness. The locations identified for sample collection included the air handler intake plenum and recirculation mixing chamber, filtered air in the downstream plenum, inside the ductwork prior to entry into the laminar flow system, and inside the operating room at table level. Using airflow particulate counting equipment, a method was developed to count particulates in the air stream at each of the critical airflow points. The result of the study provided a reference by which the hospital could conclude if the filtration system as designed and installed achieved performance requirements and ultimately provided protection for surgery patients.
M. Tortora, Hartford Hospital, Hartford, CT.
The amount of waste anesthetic gas over exposures to operating room (OR) staff members is related to many different variables. Despite engineering and administrative controls, over-exposures (above 2 parts per million for an 8-hour time weighted average) still occur. Equipment used, staff technique, type of case, and duration of cases may be the major variables. This study investigates the amount of anesthetic gas exposures to operating room staff, taking into account these variables and attempts to pinpoint when or what factors result in high exposures over the course of an 8-hour shift.
A data-logging infrared spectrophotometer (TEI Miran) is used to conduct sampling in different operating rooms. A piece of tygon tubing is attached to the inlet wand on the Miran, and placed in such a position as to simulate personal sampling. The sampling is conducted in one room for an entire shift. The OR schedule determines the type and duration of each case performed in that room, in addition to which personnel are working in that room. These results can be analyzed and these variables can be compared to each other to determine what is causing any overexposures and when the exposures are the highest. Data-logging with the Miran pinpoints spikes in the data, which will demonstrate where the highest exposures occur during the shift.
J. Morrison, G. Crawford, Boelter & Yates Inc., Park Ridge, IL.
A light scattering particle counter was used to monitor air quality and particle loading of a surgical suite and other hospital locations over a 14-month period during a major building project. Particle counts were obtained in 14 air handling unit zones in six size ranges (0.5 to 10.0 microns). As the project progressed, elevated readings were increasingly observed in the 2.0 micron (um) size range at terminal ceiling filters and in general operating room air. Since this is a common size range for mold spores and also considered respirable, it was desired to know what the nature of the particulate fraction was. Airborne mold testing with PCR analysis did not reveal significant airborne mold levels. Airborne dust samples were therefore collected in an effort to characterize the particulate fraction, particularly in the 2.0 um size range. Samples were analyzed through polarized light microscopy. Results suggested carbonaceous particles and conglomerates as a likely source of particle counts. Computed filter loading percentages of these particles corresponded well with the rank order of the light scattering particle counts. The absence of significant mold presence was reassuring, however the airborne level of 2.0-um particles, likely associated with construction activity, was significant. Ambient air counts in operating rooms averaged 8000 particles per cubic meter (range 0–45,000, n = 27) and 226,000 particles per cubic meter in other locations (range 0–1,146,000, n = 57). Such particle loading may serve to mask the presence of lower particle concentrations of greater medical concern, such as mold. Supplemental fungal testing for species of medical concern may be well advised if greater confidence in particle data is desired.
L. Lee, University of Texas, Houston, TX.
Following the events of September 11th, 2001, emergency management gained a new meaning especially in health care facilities. Right after those events, Joint Commission on Accreditation of Health Care Organizations came out with their new standards on emergency management that laid emphasis on the use of the Incident Command System. Many health care facilities followed the HEICS (Hospital Emergency Incident Command System) model for developing their incident command system. M.D. Anderson Cancer Center took a slightly different approach on how their emergency plan was rewritten. HEICS was used as a basis for developing an incident command system, but the model was customized to meet the needs of a specialty cancer hospital. The new incident command system that was developed is an all-hazards system and the organization is position-specific rather than person-specific. There is a specific chain of command, and it facilitates communications and mutual aid with other hospitals and outside agencies through the use of a common language. The new plan has been in existence for a year now and has been drilled several times. The key to the development of a successful emergency plan lies in obtaining management buy-in, management involvement, and feedback in developing their job action sheets for the plan and transferring the ownership of the plan to management. This also facilitated active involvement from management in training sessions and emergency drills. This new model has been a success at M.D. Anderson due to active management involvement, training, and frequent emergency drills.
L. Lee, University of Texas, Houston, TX.
Increased scrutiny of environmental compliance at educational institutions has resulted in the ISO 14001 registration of several U.S. universities. On December 21, 2001, The University of Texas M.D. Anderson Cancer Center became one of the first U.S. health care institutions and universities to achieve ISO 14001 registration. ISO 14001 is a performance-based international standard that sets requirements for the establishment of an environmental management system. ISO terminology, while common in industry, is just beginning to make its way into the laboratory safety and university arenas. M.D. Anderson undertook the development of an environmental management system and voluntary third party certification in keeping with M.D. Anderson’s business strategies, to develop a systematic and organized approach to managing the environmental effects of its operations, to establish a sound approach to risk management, to provide objective observations and metrics that would lead to measurable improvements, and to measure our progress against “The Gold Standard” (ISO 14001). A timeline of M.D. Anderson’s successful journey to certification, including several “eye-opening” lessons learned along the way, is detailed. A breakdown of the financial commitment involved with third party registration is given, as well as, the benefits of implementing ISO 14001. M.D. Anderson is currently maintaining its registration, with third-party surveillance audits performed every six months. Finally, a glimpse of M.D. Anderson’s environmental management system web page is provided.
Posted May 30, 2004