The U.S. Occupational Safety and Health Administration defines occupational exposure as a “reasonably anticipated skin, eye, mucous membrane, or parenteral contact with blood or other potentially infectious materials that may result from the performance of the employee’s duties.”¹ Blood is defined as “human blood, blood products, or blood components.”¹ Other potentially infectious materials are defined as “human body fluids, such as saliva, semen, and vaginal secretions; cerebrospinal, synovial, pleural, pericardial, peritoneal, and amniotic fluids; any body fluids visibly contaminated with blood; unfixed human tissue or organs; HIV [human immunodeficiency virus] or HBV [hepatitis B virus] containing cell or tissue cultures, culture mediums, or other solutions; and all body fluids where it is difficult or impossible to differentiate between body fluids.”¹ Healthcare workers should treat all bodily secretions, fluids, and tissues as potentially infectious.

The Hospital Infection Control Practices Advisory Committee of the Centers for Disease Control and Prevention lists select infections and conditions that may be encountered in the ED, along with recommended occupational exposure precautions.^2,3,4 The concept of standard precautions is built on the premise that healthcare workers cannot readily identify patients who are infected or at risk for infection. This is why using infection control practices and personal protective equipment during all patient care activities is key.

U.S. Occupational Safety and Health Administration federal regulations prescribe safeguards to protect workers and reduce risk of exposure to blood and body fluids.⁵ Updated and detailed standards (known as the Bloodborne Pathogens Standard) are in Title 29 of the Code of Federal Regulations and amended by the Needlestick Safety and Prevention Act.^6,7 The standards require healthcare facilities (1) to develop a written exposure control plan, (2) to use engineering controls to reduce risk by removing the hazard or isolating the worker from exposure, (3) to use work practice controls to standardize and maximize the safety with which work tasks are performed, (4) to identify mechanisms for compliance with Title 29 standards, and (5) to communicate workplace hazards to those with potential for bloodborne disease exposures. The Centers for Disease Control and Prevention and U.S. Occupational Safety and Health Administration Web sites provide the most up to date information regarding current regulations and standards.

Portals for infectious disease entry are percutaneous, mucous membrane (oral, ocular, nasal, vaginal, or rectal), respiratory, and dermal. The risk of infection in an exposed healthcare provider depends on (1) the route (portal) of exposure, (2) the concentration (number of organisms) of the pathogen in the infectious material, (3) the infectious characteristics (virility) of the pathogen, (4) the volume (dose) of infectious material, and (5) the immunocompetence (susceptibility) of the exposed individual.

Percutaneous exposures pose the highest risk of transmission for bloodborne disease. Needle sticks and lacerations by sharp objects account for the majority of percutaneous injuries. Phlebotomy, initiation of IV access, manipulation of access devices, suturing, and medication injection all put workers at risk.

Mucous membrane exposures result from splatters, splashes, and sprays of blood and body fluids. Tasks associated with risk of mucous membrane exposure include wound management (hemorrhage control, exploration, irrigation, debridement), airway suctioning, nasogastric or orogastric tube placement, intubation, and specimen handling.

Respiratory exposures occur through inhalation of airborne or droplet particulate materials. Exposure risk grows when an individual is confined with an expectorating, coughing, or sneezing patient for prolonged periods or in a poorly ventilated environment.

Dermal exposure involves skin contact with patients (direct contact) or environmental surfaces or objects contaminated with infectious materials (indirect contact). The risk of infection increases if the contact involves a large surface area or nonintact skin (abraded, chapped, or excoriated). Drug-resistant organisms (e.g., methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci) and parasites of the integument (e.g., scabies, lice) are transmitted by dermal exposure. Workplace activities associated with dermal exposure include patient examination, turning or moving patients, and changing linens or wound dressings. Healthcare workers are also at risk for hypersensitivity reactions to specific inert substances, notably latex, after prolonged or repeated dermal exposure.

Infection control practices seek to prevent transmission of microbial agents and to provide a wide margin of safety for healthcare workers. These practices include hand washing; use of personal protective equipment; cleaning, disinfecting, and sterilizing patient care equipment and environmental surfaces; decontamination and laundering of soiled uniforms, clothing, and patients’ linens; disposal of needles, sharps, and infectious waste; and patient location. Infection control measures that are simple, part of the routine work environment, and uniform across all situations have the greatest likelihood of compliance.

A complete infection control program includes administrative controls, equipment engineering, work practice controls, education of the workforce, and medical management.

Administrative controls organize, define, and direct infection control activities. The written infection control (exposure) plan defines all policies, procedures, and activities related to the education, prevention, and management of infectious diseases in the workforce. Initial and recurrent training in infectious disease hazards and risk activities must be provided to all healthcare workers.

Equipment engineering reduces employee exposure by removing hazards or isolating healthcare workers from exposure. Examples include self-sheathing needles, needleless drug administration devices, sharps containers, disposable airway equipment, syringe splash guards, and personal protective equipment. Medical safety devices reduce occupational exposures experienced by healthcare personnel and should be used whenever possible.

Personal protective equipment is “specialized clothing or equipment which does not permit blood or potentially infectious substances to pass through or reach worker clothing, skin, eyes, mouth, or other mucous membranes under normal conditions of use.”¹ Personal protective equipment includes examination gloves, facemasks, eye protection, face shields, and impervious gowns, leggings, and shoe covers. Personal protective equipment mitigates occupational exposures experienced by healthcare personnel; it limits but does not eliminate exposure risks. Recommendations for task-specific use of personal protective equipment are provided in Table 162-1.⁸

Work practice controls modify the performance of a task to minimize exposure to blood and blood-containing body fluids and infectious materials. Work practice controls include policies to guide disposal of needles and sharps containers (i.e., avoid shearing, bending, recapping, or breaking); disposal of contaminated linens, clothing, and infectious waste; disinfection of reusable equipment; and restriction of employee activities (eating, drinking, smoking, and application of cosmetics) in work areas where there is a reasonable likelihood of exposure to blood and body fluids.

Workforce education includes information about the agents of infectious disease, epidemiology, disease transmission, signs and symptoms, risky work activities, risk reduction strategies, and postexposure management. Education must occur at the time of initial employment, with recurrent training at specified intervals.

Medical management practices include preexposure preventive vaccinations, postexposure medical evaluation, testing, infectious disease counseling, disease prophylaxis, and referral. The U.S. Occupational Safety and Health Administration mandates preexposure vaccines at initial employee training and within 10 days of employment for all personnel at risk of exposure.¹ The Advisory Committee on Immunization Practices and the Hospital Infection Control Practices Advisory Committee make specific recommendations concerning the use of certain immunizing agents in healthcare personnel.⁹

Once an infectious exposure has occurred, healthcare workers should have access to a plan for postexposure prophylaxis (PEP) medical management 24 hours a day. The plan should include immediate medical assessment, risk analysis, counseling, treatment and prophylaxis, and follow-up appropriate to the type and source of the exposure.^{9,10,11,12,13,14}

An outline for a standardized initial approach is shown in Table 162-2.¹¹

The medical record of care for the exposed patient (the occupational exposure report) should contain specific information relative to the exposure incident. Key elements include the circumstances of exposure, medical history of the source person, and medical history of the exposed person per Centers for Disease Control and Prevention recommendations (Table 162-3).¹⁰

INITIAL TREATMENT AND ASSESSMENT

Thoroughly wash exposed wounds and skin sites with soap and water, and irrigate mucous membranes with water. Do not apply caustics (bleach), antiseptics, or disinfectants directly to the wound.

Evaluate the exposure event for the potential to transmit hepatitis B virus, hepatitis C virus, and human immunodeficiency virus (HIV) based on the type of body substance involved and the route and volume of the exposure (Table 162-4).¹⁰ Blood, fluid containing visible blood, human tissue, or other potentially infectious material (including semen, vaginal secretions, and cerebrospinal, synovial, pleural, peritoneal, pericardial, and amniotic fluids) may transmit bloodborne viruses. Percutaneous injury or mucous membrane contact with these substances conveys risk for virus transmission. Dermal contact with these substances does not convey risk of virus transmission unless the skin is not intact (abraded, chapped, excoriated, open wound).

TESTING FOR EXPOSURE

Perform diagnostic testing to determine the hepatitis B virus, hepatitis C virus, and HIV infection status of an exposure source as soon as possible and with consent (Table 162-5).¹⁰ If possible, obtain a rapid HIV-antibody on the exposure source; direct viral assays (HIV p24 antigen enzyme immunoassay, HIV RNA, hepatitis C virus RNA) are not recommended. Testing of needles or sharps instruments for contamination is also not recommended. If the exposure source is HIV positive, obtain additional information as available including CD4+ T-cell count, viral load, current and previous antiretroviral therapy, and history of antiretroviral resistance and prognosis to help identify optimal PEP regimen. If this information is not known at the time of exposure, do not delay the initiation of PEP, as changes in the regimen may be made on follow-up within 72 hours after exposure.¹⁰

HEPATITIS B VIRUS EXPOSURE AND PEP

Factors in the management of hepatitis B virus exposure include the hepatitis B surface antigen status of the source and the hepatitis B vaccination and vaccine response status of the exposed person. Following a percutaneous exposure, the estimated risks of hepatitis in unvaccinated healthcare workers are 22% to 31% (source patient positive for hepatitis B surface antigen and hepatitis B e antigen) and 1% to 6% (source patient positive for hepatitis B surface antigen and negative for hepatitis B e antigen). The estimated risk of transmission is lower following mucous membrane exposure, nonintact skin exposure, or an exposure involving nonbloody fluids or tissues.¹⁰ Every unvaccinated healthcare worker exposed to blood or body fluids should receive the hepatitis B vaccine series. For the rest, recommendations for PEP following hepatitis B virus exposure vary according to the hepatitis B surface antigen status of the exposure source and the vaccination/vaccine-response status of the exposed person (Table 162-6).¹⁰ If hepatitis B immunoglobulin is indicated, give it as soon as possible after the exposure (ideally within 24 hours); after 7 days, the effectiveness of hepatitis B immunoglobulin is unknown.