THE WESTERN JOURNAL OF MEDICINE * APRIL 1992
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156 * 4
Needle-stick Injuries Among Health Care Professionals NEEDLE-STICK ACCIDENTS account for a substantial number of injuries among hospital workers each year. Investigators have found that nursing personnel report nearly 30 needle sticks per 100 full-time-equivalent employees per year. Potential exposures are not limited to needle sticks alone, because manipulation of other sharp instruments or mucous membrane exposures to infected bodily fluids also can result in the transmission of infectious diseases. Quantifying the precise risk for disease transmission following mucocutaneous exposures is difficult because many go unreported. House staff, for example, fail to report between 60% and 95% of exposures. Although underreporting has complicated the analysis of risk for transmission of disease, risk factors for injury have been described. Needle-stick injury often occurs during unnecessary handling of a used needle. Needles should, therefore, never be recapped or otherwise unnecessarily handled after use. Care should be taken to place used needles in puncture-resistant containers as soon as possible following a procedure. Persons doing procedures involving needles or other sharp instruments should be responsible for proper disposal. Multiple-step processes, such as obtaining central venous access, should be done with forethought and care so the risk for accidental percutaneous exposure is limited. Routine drawing of blood also should be planned carefully. For example, recent studies document that it is not necessary to change needles to avoid contamination when inoculating blood cultures. Hospital personnel should be given specific instruction in methods and techniques to avoid potential exposures. This important health education process should be incorporated into the orientation process for new employees, as well as into periodic departmental meetings as mandated by recent Occupational Safety and Health Administration (OSHA) requirements. While there is considerable evidence to suggest that hepatitis B is readily transmissible by needle-stick or other mucocutaneous exposure, the potential for transmitting the human immunodeficiency virus (HIV) is not as well known. For example, the potential for transmitting hepatitis B from an infected patient to a health care professional through needle stick has been variously estimated at between 5% and 35%. By comparison, the risk of transmitting HIV by a needle stick approached 0.3% in one large prospective study. Because there are an estimated 800,000 needle-stick injuries per year and an estimated prevalence of HIV infection approaching 2% among hospital patients, one author has estimated a potential for 48 cases of HIV seroconversion per year among health care workers in the United States. Although there is considerable interest in developing new technologies to prevent all mucocutaneous exposures, the first line of defense for health care workers is prevention. High-risk areas, such as operating rooms, emergency departments, and intensive care units, should be designed so that there is adequate lighting and that puncture-proof sharps disposal containers are easily accessible. Personnel should be advised of the importance of complying with the universal precautions guidelines promulgated by the Centers for Dis-
409
ease Control, and efforts should be made to increase the use of the new "'needleless" systems that minimize exposure to used needles. The benefit of prophylaxis following percutaneous exposure to hepatitis B infection is well documented. Nonvaccinated employees should be offered hepatitis B immune globulin and the hepatitis B vaccination series. A highly effective vaccine exists for this disease, however, and all personnel at risk should be offered it before starting work. Because there are no specific antibody preparations for prophylaxis following HIV exposure, the benefit of using zidovudine (AZT) for postexposure prophylaxis for health care professionals with occupational exposure to HIV is now being evaluated in an open trial sponsored by the Centers for Disease Control. If any degree of efficacy can be shown, it is likely that the potential for long-term benefit will far outweigh any toxicity from short-term AZT therapy. While data are still incomplete regarding efficacy, many hospitals are offering AZT prophylaxis to employees who have sustained a significant needle-stick or mucous membrane exposure to HIV-infected materials. THOMAS J. FERGUSON, MD, PhD
Davis, California REFERENCES Centers for Disease Control: Public health service statement on management of occupational exposure to human immunodeficiency virus including considerations regarding zidovudine postexposure use. MMWR 1990; 39(RR 1): I-I I Jagger J, Pearson RD: Universal precautions: Still missing the point on needlesticks. Infection Control Hosp Epidemiol 1991; 12:211-213 Mangione CM, Gerberding JL, Cummings SR: Occupational exposure to HIV: Frequency and rates of underreporting of percutaneous and mucocutaneous exposures by medical housestaff. Am J Med 1991; 90:85-90 Tandberg D, Stewart K, Doezema D: Underreporting of contaminated needlestick injuries in emergency health care workers. Ann Emerg Med 1991; 20:66-70 US Department of Labor, Occupational Safety and Health Administration: Occupational exposure to bloodbome pathogens. 29CFR Part 1910.1030. Federal Register 1991; 56(235):64004-64182
Ergonomics-Prevention of Work-Related Musculoskeletal Disorders CHRONIC MUSCULOSKELETAL disorders associated with repetitive work are of increasing concern to industry, employees, workers' compensation insurance carriers, and regulatory agencies. The incidence of these conditions, known collectively as cumulative trauma disorders, has been increasing at a rate of about 20% per year for the past seven years- and has surpassed all other reported occupational illne'sses. The highest rates are found in manufacturing industries such as meat processing and industries with assembly-line work; in the past three years, reports also have been increasing in video display terminal-intensive tasks. The best approach to cumulative trauma is prevention. Risk factors associated with cumulative' trauma disorders, repetition of motion, extremes in joint position, prolo'nged constrained posture, mechanical pressure points, and vibration, can be decreased. These risk factors may also be influenced by job stress and work organization. Other methods of controlling' these disorders include job rotation, job enlargement, and modifying the work-rest cycle. If force is repeatedly applied over time to the same joint, muscle, tendon, or ligament, the cumulative force may cause soft-tissue microtears and trauma. The resulting injury and inflammatory response may lead to tendon and synovium
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156 * 4
Needle-stick Injuries Among Health Care Professionals NEEDLE-STICK ACCIDENTS account for a substantial number of injuries among hospital workers each year. Investigators have found that nursing personnel report nearly 30 needle sticks per 100 full-time-equivalent employees per year. Potential exposures are not limited to needle sticks alone, because manipulation of other sharp instruments or mucous membrane exposures to infected bodily fluids also can result in the transmission of infectious diseases. Quantifying the precise risk for disease transmission following mucocutaneous exposures is difficult because many go unreported. House staff, for example, fail to report between 60% and 95% of exposures. Although underreporting has complicated the analysis of risk for transmission of disease, risk factors for injury have been described. Needle-stick injury often occurs during unnecessary handling of a used needle. Needles should, therefore, never be recapped or otherwise unnecessarily handled after use. Care should be taken to place used needles in puncture-resistant containers as soon as possible following a procedure. Persons doing procedures involving needles or other sharp instruments should be responsible for proper disposal. Multiple-step processes, such as obtaining central venous access, should be done with forethought and care so the risk for accidental percutaneous exposure is limited. Routine drawing of blood also should be planned carefully. For example, recent studies document that it is not necessary to change needles to avoid contamination when inoculating blood cultures. Hospital personnel should be given specific instruction in methods and techniques to avoid potential exposures. This important health education process should be incorporated into the orientation process for new employees, as well as into periodic departmental meetings as mandated by recent Occupational Safety and Health Administration (OSHA) requirements. While there is considerable evidence to suggest that hepatitis B is readily transmissible by needle-stick or other mucocutaneous exposure, the potential for transmitting the human immunodeficiency virus (HIV) is not as well known. For example, the potential for transmitting hepatitis B from an infected patient to a health care professional through needle stick has been variously estimated at between 5% and 35%. By comparison, the risk of transmitting HIV by a needle stick approached 0.3% in one large prospective study. Because there are an estimated 800,000 needle-stick injuries per year and an estimated prevalence of HIV infection approaching 2% among hospital patients, one author has estimated a potential for 48 cases of HIV seroconversion per year among health care workers in the United States. Although there is considerable interest in developing new technologies to prevent all mucocutaneous exposures, the first line of defense for health care workers is prevention. High-risk areas, such as operating rooms, emergency departments, and intensive care units, should be designed so that there is adequate lighting and that puncture-proof sharps disposal containers are easily accessible. Personnel should be advised of the importance of complying with the universal precautions guidelines promulgated by the Centers for Dis-
409
ease Control, and efforts should be made to increase the use of the new "'needleless" systems that minimize exposure to used needles. The benefit of prophylaxis following percutaneous exposure to hepatitis B infection is well documented. Nonvaccinated employees should be offered hepatitis B immune globulin and the hepatitis B vaccination series. A highly effective vaccine exists for this disease, however, and all personnel at risk should be offered it before starting work. Because there are no specific antibody preparations for prophylaxis following HIV exposure, the benefit of using zidovudine (AZT) for postexposure prophylaxis for health care professionals with occupational exposure to HIV is now being evaluated in an open trial sponsored by the Centers for Disease Control. If any degree of efficacy can be shown, it is likely that the potential for long-term benefit will far outweigh any toxicity from short-term AZT therapy. While data are still incomplete regarding efficacy, many hospitals are offering AZT prophylaxis to employees who have sustained a significant needle-stick or mucous membrane exposure to HIV-infected materials. THOMAS J. FERGUSON, MD, PhD
Davis, California REFERENCES Centers for Disease Control: Public health service statement on management of occupational exposure to human immunodeficiency virus including considerations regarding zidovudine postexposure use. MMWR 1990; 39(RR 1): I-I I Jagger J, Pearson RD: Universal precautions: Still missing the point on needlesticks. Infection Control Hosp Epidemiol 1991; 12:211-213 Mangione CM, Gerberding JL, Cummings SR: Occupational exposure to HIV: Frequency and rates of underreporting of percutaneous and mucocutaneous exposures by medical housestaff. Am J Med 1991; 90:85-90 Tandberg D, Stewart K, Doezema D: Underreporting of contaminated needlestick injuries in emergency health care workers. Ann Emerg Med 1991; 20:66-70 US Department of Labor, Occupational Safety and Health Administration: Occupational exposure to bloodbome pathogens. 29CFR Part 1910.1030. Federal Register 1991; 56(235):64004-64182
Ergonomics-Prevention of Work-Related Musculoskeletal Disorders CHRONIC MUSCULOSKELETAL disorders associated with repetitive work are of increasing concern to industry, employees, workers' compensation insurance carriers, and regulatory agencies. The incidence of these conditions, known collectively as cumulative trauma disorders, has been increasing at a rate of about 20% per year for the past seven years- and has surpassed all other reported occupational illne'sses. The highest rates are found in manufacturing industries such as meat processing and industries with assembly-line work; in the past three years, reports also have been increasing in video display terminal-intensive tasks. The best approach to cumulative trauma is prevention. Risk factors associated with cumulative' trauma disorders, repetition of motion, extremes in joint position, prolo'nged constrained posture, mechanical pressure points, and vibration, can be decreased. These risk factors may also be influenced by job stress and work organization. Other methods of controlling' these disorders include job rotation, job enlargement, and modifying the work-rest cycle. If force is repeatedly applied over time to the same joint, muscle, tendon, or ligament, the cumulative force may cause soft-tissue microtears and trauma. The resulting injury and inflammatory response may lead to tendon and synovium
