There are at least 135 chemicals found in hospitals that are carcinogenic or mutagenic. Another 179 have been identified as skin and eye irritants. Common classes of toxic chemicals include disinfectants, sterilants, chemotherapeutic agents, and anesthetic gases. They can cause injury in two ways:
Acute toxicity to these chemicals happens as a result of an accident, usually a spill. The exposure is sudden and requires emergency response. Acute exposures cause skin, eye, or respiratory damage. The severity of the damage depends upon the strength of the chemical and length of contact. Your facility must have an emergency response team knowledgeable of the potential chemical risks in your facility and equipped with the required interventions to minimize and treat the effects.
Chronic toxicity is exposure to low levels of toxic chemicals over extended periods of time, through inhalation or other contact. Preventing chronic exposure requires knowledge of the potential hazard, necessary safeguards, and the exposure limits and standards promulgated by OSHA. Remember that OSHA standards and chemical formulations change, so it's important to stay up to date on any hazardous chemicals in your facility. It is also imperative that you acquaint yourself with the manufacturers' directions and recommendations for how to measure and comply with current exposure limits for chemical products. Do not buy or use any toxic chemical without these recommendations.
Chemicals to be particularly aware of are:
- isopropyl alcohol,
- chlorine dioxide,
- ethylene oxide,
- phenols, and
- quaternary compounds.
Healthcare workers are at risk for contracting TB, influenza, measles, chickenpox, Legionnaires' disease and various other viral and fungal aerosolized infections. Anthrax and smallpox, two agents that have recently been in the news as potential terrorist weapons, are also aerosolized agents. The ability of a microorganism to cause disease is measured by its virulence and invasiveness. The more virulent a microorganism is the more severe and more communicable the disease. Invasiveness is the ability to penetrate tissue. Also important are dosage, modes of transmission and the susceptibility of the host.
Think of your environment as a distinct ecosystem in which you interact with a myriad of environmental occurrences from your patients, your co-workers and your building. To ensure that these occurrences present the least amount of employee risk, it's crucial to have an understanding of the factors affecting the generation, survival and transmission of infectious aerosols in your facility. Once you understand the factors, you can combat these infections in the following five ways:
Source management: If you pinpoint a potential infection source, manage it by removal, isolation, mechanical means, and/or maintenance. Some suggestions:
- Screen all patients properly for pre-existing conditions.
- If you discover mold in the walls, you must cut it out and, in some cases, replace the walls. Mold is extremely difficult to remove entirely, and by the time you notice it, it may have already spread throughout the wall.
- Routinely inspect your building, focusing on potential sources such as air intakes, filter banks, HVAC equipment, cooling towers and hot water systems.
Activity management: Ensure that the activities going on in your environment are appropriate for the designated purpose. Are you doing laboratory work in a space designed for an office? Do you eat and drink only in designated areas? Are you continually expanding or modifying your existing structure-if you are, you may be creating new infection sources and not even realize it. Using your facility (building, rooms, work areas) in a way that it was originally intended promotes a routine program for inspection, maintenance, and cleaning.
Design intervention: Buildings, equipment, and furnishings need to be designed so that they can be effectively inspected, maintained and cleaned. A few suggestions:
- It has been shown that carpeting can be an effective breeding ground for infectious agents that will aerosolize when disturbed. Leather and plastic may not have the warmth and/or economics of cloth, but they are much easier to clean.
- Make sure that places that gather dust are reachable by routine cleaning. Ceiling tiles are particularly susceptible to microbial contamination.
- Do not add space or equipment to your facility without first consulting an infection control practitioner and a certified industrial hygienist.
Dilution intervention: you can dilute infectious airborne particles by replacing contaminated air with fresh air; you can remove the particles with filters. Make sure every room in your facility is well ventilated with filtered air.
Cleaning intervention: Cleaning is the final and ultimate defense in managing indoor environmental contamination. With all the previous interventions well in place, cleaning is still necessary and desirable. Don't rely on brooms and dusters-they simply scatter and aerosol particles. Employ wet vacuum and damp dusting techniques instead.
Contaminated supplies and equipment pose a substantial employee hazard unless they are safely handled and disposed of or cleaned. Proper cleaning makes instruments safe to handle and increases the probability that subsequent disinfection and/or sterilization will be effective. To ensure adequate cleaning, I suggest the following:
- Centralize the activity. While this may not be possible in all situations, centralizing makes it easier to control the necessary environmental factors for the space needed as well as limit the number of trained workers needed. The fewer decontam workers and the better trained they are, the lower the risk.
- Provide adequate and properly designed space. This includes designing functional work flow patterns (not mixing and crisscrossing clean and dirty); having easy-to-clean ceilings, walls, floors, and work stations; temperature controlling the environment to between 68 and 73 degrees F; humidity controlling the environment to 50 percent plus or minus 10 percent; installing negative air pressure; and enforcing restricted access.
- Provide proper and adequate handwashing policies and facilities. They should be designed to eliminate hand contact with faucets, conveniently near the decontam area, and separate from the sinks used for cleaning contaminated supplies.
- Train your personnel and make sure they are all vaccinated against hepatitis B.
- Provide attire suited for decontamination activities; for example, waterproof shoes or boots with non-skid soles, full length pants and tucked-in shirt or a close-fitting tunic top, waterproof apron, heavy duty gloves, and when necessary, eye protection and high-filtration face masks. Before leaving the decontam area, employees should remove their protective attire in an area specifically provided for donning and removing this attire.
Bloodborne pathogen protection and treatment
We have covered the topic of bloodborne pathogens many times before in Outpatient Surgery, but no article on employee safety would be complete without a brief discussion of the three most lethal pathogens.
Hepatitis B: Occupationally acquired HBV continues to cause significant morbidity and occasional mortality among healthcare workers in the US (about 100 healthcare workers per year die of occupationally acquired HBV). In 1991 OSHA mandated that all healthcare workers that could be exposed to blood and blood products, or other potentially infectious materials, be offered hepatitis B vaccine free of charge. Compliance has dramatically reduced the rate of occupationally acquired HBV; unfortunately, many healthcare workers have declined to be vaccinated despite the mandate and compelling reasons to comply. Also, about 10 to 12 percent of vaccinated persons do not develop the necessary antibodies after the recommended three-dose series. Risk factors for failure to seroconvert include age, smoking, and obesity. The best protection against HBV, of course, is to observe Universal Precautions and get vaccinated.
Hepatitis C: About 30,000 hepatitis C cases are diagnosed annually, and unlike hepatitis B, there are no vaccines available. Treatment with a combination of interferon alpha and ribavirin has been shown to eliminate the virus in approximately 40 percent of patients with mild to moderate hepatitis and 20 percent of patients with cirrhosis. For this disease, therefore, the only real defense is prevention.
HIV: HIV, of course, continues to be the "killer" virus. HIV-positive individuals have benefited from new and better drug treatment that delays but does not eliminate the eventual outcome. The risk factors of unprotected sex, re-use of needles, and exposures to infected blood are well known. Yet there has been only a slight decline in reported cases in the US, and it is a major health risk in many third world countries, especially in Africa.
Unlike HBV and HCV, the HIV virus has a very short life when not protected by blood and other bodily fluids; furthermore, it is now known that systemic infection does not occur immediately, leaving a window during which treatment may prevent or alter viral replication. Strict adherence to Universal Precautions and safe sharps handling will eliminate HIV as a viable employee risk factor. Workers exposed to HIV on the job should receive a prescribed regimen proven to be effective. According to the CDC a four-week program of two drugs-zidovudine and lamivudine is recommended. A protease inhibitor should be added if there is increased risk for transmission or if the source's virus is or is suspected to be drug resistant. Note that AIDS treatment is a constantly changing issue, and you should always strive to have the most current information on hand. The CDC is your best source for reliable and up-to-date information.
- Always regard all blood and body fluids as potentially infectious and follow Universal Precautions.
- Remember that the highest risk areas for sharps injuries are drawing blood, passing instruments during surgery and needle recapping. Compared to the number of procedures performed, these risks are very small. However, switching to safety devices such as blunt needles and needle-less syringes will reduce the risk even further.
- Treat any exposure to blood or body fluids as urgent, and start treatment immediately. Wash wounds or exposed skin sites liberally with soap and water and flush any exposed mucous membranes with copious amounts of water.