ATS Pulmonary Function Laboratory Manual

chapter  4

Direct Contact : There is the potential for transmission of upper respiratory disease, enteric infections, and bloodborne infections through direct contact. Although hepatitis and HIV transmission are unlikely via saliva, disease transmission is a possibility when there are open sores on the oral mucosa, bleeding gums, or hemopty- sis. The most likely surfaces for contact are mouthpieces and the immediate proximal surfaces of valves or tubing (3). Mouthpieces, nose clips, and any other equipment coming into direct contact with mucosal surfaces should be disinfected, sterilized, or, if disposable, discarded after each use. Although the optimal frequency for disin- fection or sterilization of tubing, valves, or manifolds has not been established, any equipment surface showing visible condensation from expired air should be disinfected or sterilized before reuse whenever the potential for cross contamination exists. Indirect Contact : There is potential for transmission of TB, various viral infections, and possibly, opportunistic infections and nosocomial pneumonia through aerosol droplets. The most likely surfaces for possible contamina- tion by this route are mouthpieces and proximal valves and tubing (3). The Clinical and Laboratory Standards Institute (CLSI) has published a guideline addressing laboratory worker protection from biohazards (4), and the Centers for Disease Control and Prevention (CDC) has published recom- mendations on how to control nosocomial-acquired pneumonia (5). These documents should be in all PF labora- tories and available to interested parties. Some disease-prevention areas that should be addressed include: 1. Proper hand-washing techniques 2. Disinfection or sterilization of tubing, valves, and manifolds 3. Flushing volume-displacement spirometers between patients 4. Environmental engineering controls 5. Precautions with testing patients having hemoptysis or open sores 6. Precautions with patients with known (or suspected) transmissible infectious diseases 7. Efficacy of in-line filters 8. Manufacturer design of equipment to deal with equipment disinfection issues 1. Standard Precautions Standard precautions (SP) (as published by the CDC) (5) should be applied in all instances in which there is evidence of contamination with blood (e.g., pneumotachometers and adapters). 1.1. Although SP do not apply to saliva or mucus, unless it contains blood, other potentially hazardous organisms may be present in these fluids even in the absence of blood, and the appropriate use of barriers and hand washing is recommended (6, 7). 1.2. Departments should have specific procedures for handling and disposing of articles contaminated with bloodborne pathogens. 2. Mycobacterium tuberculosis (TB) 2.1. M. tuberculosis is carried in airborne particles (droplet nuclei) that can be generated when persons who have pulmonary or laryngeal TB sneeze, cough, speak, or sing. 2.2. Infection occurs when a susceptible person inhales droplet nuclei containing M. tuberculosis , and these droplet nuclei then traverse the mouth or nasal passages, upper respiratory tract, and bronchi to reach the alveoli. Once in the alveoli, the organisms are taken up by alveolar macrophages and may be spread throughout the body (8). 2.3. The risk of nosocomial transmission is higher in areas where patients with TB receive care before diag- nosis and initiation of TB treatment and isolation precautions (e.g., clinic waiting areas and emergency departments). In addition, the risk is higher in areas where diagnostic or treatment procedures that stimulate coughing (e.g., PF tests and bronchoscopy) are performed.

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