To prevent the spread of infection, health care workers must collaborate in a concerted effort to protect patients and themselves.
It the end of World War II, it was hoped that the discovery of antibiotics would significantly decrease illnesses caused by infectious bacteria worldwide. It was hypothesized that diseases such as tuberculosis would disappear and that childhood diseases such as polio, diphtheria, and pertussis could be eliminated through the use of vaccination. Some of these hopes were short-lived: the emergence of resistant strains of bacteria, the appearance of AIDS, and changes in the health care delivery system have led to a new outlook on infectious diseases.
Infectious diseases cause undue pain and suffering and place an enormous financial burden on society. Nosocomial infections alone cost the United States $5 to $10 billion per year. Bacteremia causes patients to stay in the hospital an average of 7 additional days and results in an average of $3,517 in additional hospital charges per infected patient.1 In order to prevent the spread of infection in the hospital, it is important to emphasize hand washing, the application of standard precautions, the development of equipment cleaning and disinfection policies and procedures, and vaccination.
Hand washing is the single most important action that health care workers can take to prevent the spread of infection to patients and to themselves. This process removes soil and transient microorganisms from the hands.2 The skin of patients and health care workers can serve as a reservoir for bacteria and as a vehicle for the transfer of infectious bacteria to a susceptible host. The skin is covered by both resident and transient microorganisms. Resident flora are microorganisms that are persistently isolated from the skin. These microorganisms are considered permanent residents of the skin and are not readily removed by mechanical friction. 2 Transient microorganisms are microbes not consistently found on the skin. These bacteria are contaminants that can survive on the skin for a limited period of time. If transient microorganisms are not removed from the hands by washing, it is possible to transfer these bacteria from one person to another.
Plain soaps and detergents or antimicrobial products can be used for hand washing. These soaps and detergent-based cleansers are available as bars, liquids, and powders. The primary purpose of these products is to remove dirt and microorganisms physically. Such soaps and detergents work principally through mechanical action and have no antibacterial activity. 2 Antimicrobial products, however, kill or inhibit the growth of microorganisms; this process is referred to as antisepsis. Another characteristic of an antimicrobial cleanser is the ability of the soap/detergent to adhere to the skin, which results in persistent activity on the skin’s surface. Microorganisms proliferate on the hands within the moist environment of latex or plastic gloves, 3,4 and this increases the risk of bacterial transfer to patients if health care workers do not wash their hands. The choice between plain soap or detergent and an antibacterial product should be made based on the amount of hand contamination and the need to reduce the quantity of resident flora on health care workers’ hands.
Health care workers should wash their hands for 10 to 15 seconds with cleanser and water. It is important to wash the hands before
o beginning duty,
o working with a patient, or
o performing sterile procedures.
It is equally important to wash the hands after
o they have become soiled,
o the restroom has been used,
o gloves have been removed, or
o contaminated equipment has been touched.
A major problem associated with hand washing is lack of compliance. When health care workers have been observed, 2 it has been noted that they wash their hands only half of the time that washing is indicated and/or do not wash them as long as recommended. Health care workers perceive that they wash their hands more than they actually do. It is important to provide continual feedback to staff about hand-washing practices, to provide updates and education as needed, and to incorporate staff suggestions on ways to increase compliance.
Prior to the development of standard precautions, two systems of isolation and precautions existed: category-specific isolation grouped all infectious diseases into six categories based on their mechanism of transmission, and disease-specific isolation applied specific measures to specific infectious diseases. 5 In 1987, universal precautions were designed as a supplement to category-specific isolation. The intent of universal precautions was to protect health care workers from infection by preventing contact with the blood, and with certain bodily fluids, of all patients. 6
Standard precautions were developed by the Centers for Disease Control and Prevention (CDC) in 1996. Standard precautions are a set of behaviors that the health care worker applies to reduce the risk of transmission of infectious diseases. Standard precautions expand the coverage of universal precautions by recognizing that any bodily fluid may contain contagious microorganisms. In summary, standard precautions protect the health care worker and patient from the risk of acquiring all microorganisms, rather than blood-borne pathogens alone. Standard precautions are based on the premises that many patients are infected by organisms that can be spread in the hospital setting, many of the infections that patients carry are not easily detectable before (or at the time that) care is given, and that precautions are determined by the activities of the health care worker rather than based on the recognized infections of patients.
Standard precautions require consistent and thorough hand washing between patient contacts, after glove removal, and after contact with all bodily fluids. Gloves are needed for touching bodily fluids, mucous membranes, or contaminated surfaces. Gowns are necessary to prevent work clothes from becoming soiled or wet. Face masks and/or eye coverings are required during procedures that involve the possibility of a spray or splash. Patient-care equipment should be handled in a manner designed to prevent skin and mucous-membrane exposure, contamination of clothing, and transfer of microorganisms to other patients and the environment. Reusable equipment must be cleaned and reprocessed before use on another patient. Employees should protect themselves from needle-stick injuries by remembering not to cap needles, by disposing of all sharp instruments in puncture-resistant containers, and by avoiding manipulating sharp instruments in any way. If resuscitation is needed, the use of mouthpieces, resuscitation bags, or ventilation devices is recommended. 7
While standard precautions apply to all patients, transmission-based precautions apply only to selected patients and are based on either a suspected or confirmed clinical syndrome or a specific diagnosis.7 Transmission-based precautions are divided into categories that reflect the major modes of transmission of infectious agents within the health care setting: airborne, droplet, and contact. Some diseases require more than one category of isolation,8 and some diseases no longer require patient isolation as a result of the application of standard precautions.
Policies and procedures are documents developed to standardize the way in which practice should occur in the health care setting. The benefits of documented policies and procedures include staff education, improved standards of care, and increased staff compliance. As the ability to support ventilation in the patient with respiratory insufficiency has improved, the risk of nosocomial infection from increasingly invasive and prolonged therapeutic intervention has received more attention. The introduction of new technology, along with the need to review the usefulness of older procedural recommendations for new equipment, continues to raise questions for infection control and respiratory care departments as they strive to improve patient care, to prevent nosocomial infections, and to remain cost-effective.9 There are many published infection-control guidelines for respiratory equipment, including those of the CDC, the Society for Healthcare Epidemiology in America, the American Thoracic Society, the Association for Professionals in Infection Control and Epidemiology Inc, and the American Association for Respiratory Care.10-12 The guidelines in these published reports can be tailored to a particular health care setting’s need.
Published reports10-12 have also documented the role that respiratory equipment has played in the transmission of bacteria into the respiratory tract. Large numbers of viable bacteria can be aerosolized by nebulizers and can invade the lower respiratory tract. Contaminated nebulizers are a common source of pulmonary infection (as opposed to humidifiers or heat/moisture exchangers). At times, solutions or medications contaminated before use can be the initial source of bacterial contamination. Many pieces of respiratory equipment use water to operate, and the growth of certain bacteria (such as Pseudomonas aeruginosa and Serratia marcescens) is supported by water. Bacteria can multiply in the water that is trapped in tubing, can be aerosolized, and can then travel into the patient’s respiratory tract. Large-volume nebulizers pose the highest infection risk. Small-volume medication nebulizers have been shown to pose a lesser infection risk, but they are, of course, still capable of generating aerosols. The medications themselves, particularly those in multidose vials, have been a source of contamination of small-volume nebulizers.
It should be the respiratory therapy department’s policy to clean all equipment and devices thoroughly before they are sterilized or disinfected. Follow the manufacturers’ recommendations for cleaning, disinfection, or sterilization. Use sterile water for rinsing reusable respiratory equipment (for example, nebulizer cups). Do not reprocess any equipment or device that is manufactured for single-patient use only or that is disposable, unless the institution has a reuse policy.
Ventilator circuits should be changed no more frequently than every 48 hours that circuits are connected to humidifiers. Circuits with hygroscopic-condenser/humidifiers or heat/moisture exchangers do not need routine circuit changes. Change any circuit, however, when it is visibly soiled or when the integrity of the circuit is questioned. When assembling the circuit, keep it off the floor.
The internal mechanisms of ventilators do not need to be disinfected or sterilized routinely. During use, wipe down the ventilator with a hospital-approved disinfectant.
Drain tubing condensate away from the patient and humidifier. Disconnect the tubing to drain the condensation into a disposable cup or container.
Use sterile technique in handling tracheal suction catheters. A closed suction system will decrease the chance of splashing; if an open suction system is in place, use a sterile single-use catheter. Use only sterile fluid to remove secretions from the patient if the catheter is to be used for reentry. Fluids that are instilled into the patient’s respiratory tract must be sterile. Change suction-collection tubing between patients.
Until manual resuscitators are clean, do not reuse them for other patients. All resuscitators that are to be processed for reuse must be thoroughly cleaned before sterilization, pasteurization, or high-level disinfection.
Discard all disposable pulmonary screening devices, such as inspiratory force manometers, tidal-volume and vital-capacity devices, and peak flow meters after a single use if labelled single use only. Clean and disinfect nondisposable products between patients; use of a filter is recommended.
After each small-volume nebulizer treatment, rinse the medication nebulizer with sterile water, dry it thoroughly, and store it in a clean plastic bag. Label the bag with the patient’s name. Replace nebulizers at regular intervals. Use only sterile fluids for nebulization, and dispense these fluids aseptically. If multidose medication vials are used, dispense the medication aseptically. Handle multidose vials according to the institution’s policy.
Use aseptic technique when changing tracheostomy tubes in a hospital setting.
Hands should be washed before and after contact with an intubated or tracheostomized patient, contact with any respiratory device, and contact with mucous membranes and respiratory secretions.
Clean gloves should be worn for handling respiratory secretions or objects contaminated by respiratory secretions. Gloves must be changed between patients, after handling respiratory secretions, and between contacts with a contaminated body site and the respiratory tract or a respiratory device on the same patient. A gown should be worn when soiling with respiratory secretions is anticipated. Change gowns between patients. Protective eyewear should be worn when splashing is anticipated.
Policies and procedures require periodic reviews and updates. In order to develop policies, it is helpful to collaborate with other health care professionals. The policies should be based on documentation and should reflect current practice. Do not be afraid to eliminate traditional, popular (but outdated) methods and recommendations. Any policy changes must be communicated to all personnel affected by them.
During the past century, the spread of many infectious diseases has been eliminated through the use of vaccines. It is essential that health care workers receive vaccines to protect themselves and the patients they serve. National guidelines for immunization are provided by the US Public Health Service’s Advisory Committee on Immunization Practices. 13 It has been noted that mandatory vaccination programs (for example, as a condition of employment) are effective in gaining vaccination compliance. Decisions concerning which vaccines to include in an employee immunization program can be made by considering the likelihood of staff exposure to vaccine-preventable diseases, and the potential consequences of not vaccinating personnel; the type of contact with patients and their environment typical of employees in a given category; and the characteristics of the patient population.14
Immunity to rubeola, rubella, and epidemic parotitis is required for all health care workers. 13 This immunity may be achieved through vaccination or by having experienced the disease. Hepatitis B vaccination is indicated for all personnel at risk for exposure to blood and bodily fluids. The CDC recommends that health care workers receive influenza vaccine each year. This prevents health care workers from becoming ill and passing the virus to patients. Varicella-zoster vaccination is indicated for health care workers who lack a reliable history of varicella or laboratory evidence of varicella immunity.
In order to protect patients and health care workers from infections, many challenges must be overcome. These include communicating practice changes to staff, remaining cost-effective, increasing compliance among workers, and providing high-quality care to all patients. Infection control is a team effort that relies on the cooperation of everyone involved.
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13. Centers for Disease Control and Prevention. Immunization of health-care workers: recommendations of the Advisory Committee on Immunization Practices (ACIP) and the Hospital Infection Control Practices Advisory Committee (HICPAC). MMWR Morb Mortal Wkly Rep. 1997;18:1-42.
14. Bolyard E. Guideline for infection control in healthcare personnel. Am J Infect Control. 1999;26:289-354.