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If you've ever had to report a needle-stick injury, whether it was your own or a coworker's, more than likely you've asked yourself: "What could I have done to prevent it?" According to published information from the CDC and the Association for Professionals in Infection Control and Epidemiology (APIC), over a half million needle sticks and other sharps-related injuries are sustained by hospital-based healthcare personnel annually. Exposure injuries are primarily associated with transmission of HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV), but they may be implicated in the transmission of as many as 20 other pathogens (see The HIV life cycle and Picturing a liver with the effects of hepatitis for the pathophysiology of these viruses).
And sharps-related injuries aren't the only way you can be exposed to pathogens-if a patient's blood or other potentially infectious body fluid comes in contact with your eyes, nose, mouth, or an area of open skin, you may also be at risk, although most exposures of this type don't result in infection. The risk of infection from contact with blood or body fluid varies with the pathogen involved, the type of exposure, the amount of blood or body fluid involved in the exposure, and the amount of pathogen in the patient's blood or body fluid at the time of exposure.
In this article, I'll focus on what to do if you accidentally come in contact with HIV, HBV, or HCV via an exposure injury; the preventive treatments that are available postexposure (known as postexposure prophylaxis or PEP); and how to protect yourself against needle sticks and other exposure injuries.
An exposure requires contact with a potentially infectious body fluid as defined by the Occupational Safety and Health Administration (OSHA). Besides blood and any fluid contaminated with blood, these include semen, vaginal secretions, pleural fluid, and pericardial fluid, although some are considered less likely than others to transmit infection (see Classifying potentially infectious body fluids). Feces, urine, and vomitus aren't considered potentially infectious body fluids.
Exposure also requires a portal of entry, either through nonintact skin or through mucous membranes. The CDC doesn't recommend prophylaxis in cases of contact with intact skin. Determining whether exposure has occurred can be challenging in cases of body fluid splashes on apparently intact skin or needle sticks that don't draw blood.
If you're exposed or are at the scene of an exposure incident, be aware of the emotional component of an occupational exposure. Knowing the risks, you may panic; however, remember that disease transmission via blood or potentially infectious body fluid exposure is uncommon and that you can take steps to minimize transmission risks. Immediately following an exposure:
* wash needle stick or other puncture injury sites and cuts with soap and water if blood or potentially infectious body fluid came in contact with nonintact skin
* rinse mucous membranes with copious amounts of water or normal saline solution
* flush splashes to your nose, mouth, or skin with water
* irrigate eyes with clean water, saline solution, or sterile irrigants.
No evidence indicates that squeezing a wound or washing with an antiseptic or a caustic solution reduces the risk of disease transmission. The CDC states that using antiseptics isn't contraindicated, but doesn't recommend application of caustic solutions such as bleach or the injection of antiseptics into a wound.
As soon as possible after first aid has been administered, notify your supervisor or manager and fill out the unusual occurrence or event form that your facility requires. Prompt reporting to the department managing exposures is also essential because PEP may be necessary and some decisions about PEP should be made within hours of exposure. The provider managing your exposure will need to advise you of your facility's protocol for PEP.
To determine whether you need to receive PEP it must first be determined if a true exposure to blood or potentially infectious body fluid has occurred. For example, being splashed with blood or any fluid containing blood is considered a potential exposure. Being splashed with urine, feces, or vomitus isn't because these substances aren't considered to be potentially infectious body fluids. Next, it must be determined if the blood or other potentially infectious body fluid had a portal of entry. The CDC doesn't recommend prophylaxis when body fluids make contact with intact skin.
The route of exposure plays a role in the likelihood of transmission. For example, the average risk for HIV transmission after percutaneous exposure to infected blood is 0.3%, or about 1 in 300. After mucous membrane exposure, the risk is 0.09%, or about 1 in 1,000. The average risk for infection after a needle stick or cut exposure to HCV-infected blood is actually fairly small at 1.8%, according to the CDC. The risk following a blood exposure to the eyes, nose, or mouth is unknown, but it's also believed to be very slight. The CDC does state in its brochure entitled "Exposure to Blood: What Healthcare Personnel Need to Know" that HCV infection from a blood splash to the eye has been reported and HCV transmission to nonintact skin has occurred. There doesn't seem to be a known risk from exposure to intact skin. See What's the risk? for more information.
The next step is to evaluate the source patient. If the patient's HIV, HBV, and HCV status are unknown, occupational health personnel can inquire about status and initiate testing. If the patient is known to be HIV-positive, information should be gathered about any current HIV antiretroviral therapy and its effectiveness, as determined by viral load or CD4 count. If testing is indicated, your facility's exposure control policy should address informed consent issues based on state law and CDC guidelines. In 2006, the CDC recommended eliminating the requirement for specific written consent for HIV testing; however, this recommendation hasn't been adopted by every state. For example, California requires a separate consent for HIV testing.
The rapid HIV test can provide results in 20 to 40 minutes, which is ideal because PEP for HIV infection should begin within 2 hours after exposure for best results. If the source patient's test is positive, it should be confirmed with more definitive HIV testing. In the meantime, starting PEP is indicated. If the source patient's HIV status can't be quickly determined, you may start PEP and discontinue it later if the patient is negative. The rapid HIV test may produce a false-negative result if the source patient has been infected for less than 90 days-the time needed for the body to develop enough telltale antibodies. However, barring unusual circumstances, a negative rapid HIV test is generally accepted as definitive.
Unlike HIV testing, HBV and HCV testing have never required a separate consent and blood already drawn from the source patient may be used for testing. The patient may refuse to have additional blood drawn for testing. The HBV panel for a source patient varies among facilities, but a hepatitis B surface antigen (HBsAg) is standard in all of them. A positive result indicates that the patient is capable of transmitting HBV. HBsAg appears in about 4 weeks after HBV infection and remains in those who are chronically infected. Some facilities also include a hepatitis B surface antibody (HBsAb or anti-HB) in the test bundle; a positive result is generally interpreted as immunity to HBV due to natural infection or vaccination and the source patient isn't infectious to others.
You've probably already received the HBV vaccine, which is safe and extremely effective in preventing HBV infection. All healthcare personnel who have a reasonable chance of blood and body fluid exposure should have it. Ideally, you were informed of your immunity titer 1 to 2 months after the vaccine series was completed. Anyone who has been vaccinated for hepatitis B and developed an immune response is considered to have virtually no risk of contracting HBV from exposure. If you aren't immune, risk of infection from a single needle stick or cut exposure ranges from 1% to 30%, depending on the source patient's hepatitis B e antigen (HBeAg) status. A source patient who's both HBsAg-positive and HBeAg-positive is more likely to transmit disease due to more pathogens present in the blood.
Hepatitis C antibody testing, also known as an anti-HCV test, has a high false positive rate, so a positive result must be confirmed with further testing. The preferred approach is to confirm with the recombinant immunoblot assay or HCV RNA.
Lastly, baseline assessment and testing for yourself after an exposure is important to determine if you already harbor a bloodborne infection. The medical history should include this information:
* current pregnancy or breastfeeding (Pregnancy testing should be considered for women of childbearing potential based on the healthcare provider's assessment of her exposure risk.)
* medication reconciliation
* history of HBV vaccination and whether you developed an immune response
* history of any liver or kidney problems, dyslipidemia, anemia, pancreatitis, depression, or insomnia
* any other medical or occupational information that affects your risk of infection from bloodborne pathogens.
If you never received the HBV vaccine series, you should undergo HBsAb and HBsAg testing. If you completed the HBV vaccine series and were tested afterward as HBsAb-positive, you don't need hepatitis B testing. The vaccine is considered to give lifetime protection against HBV in people who respond in this way. If you completed the vaccine series and were never tested for an immune response, you should undergo HBsAb and HbsAg testing because you may never have developed an immune response to the vaccine. If you completed the HBV vaccination over 10 years ago and weren't tested afterward, the HBsAb test may be falsely negative because of waning antibodies. If you completed the vaccine series and were tested but don't remember the results, you should contact your occupational health department for a review of your records to determine if additional doses of vaccine are indicated.
Baseline hepatitis C testing should be done with serum liver enzyme levels as soon as possible after an exposure.
If the rapid HIV test on the source patient is positive, you may decide to receive HIV PEP, which is recommended for certain exposures that pose a risk of transmission. Remember that risk increases according to the type of exposure, the amount of blood or potentially infectious body fluid involved, and the amount of the pathogen that was in the patient's blood or body fluid at the time of exposure. It should be noted that for those exposures without risk of HIV infection, such as minimal exposure or a small amount of blood or potentially infectious body fluid involved, PEP isn't recommended because the drugs used to prevent infection may have serious adverse reactions, such as nausea, diarrhea, abdominal pain, anemia, and neutropenia. You should discuss the risks and adverse reactions with your healthcare provider before starting PEP for HIV.
If you chose to receive HIV PEP, you'll need blood tests to monitor for toxic drug levels; at a minimum, testing should include a complete blood cell count and renal and hepatic function tests at baseline and after 2 weeks of therapy. If your drug regimen includes a protease inhibitor, you'll need to monitor for signs and symptoms of hyperglycemia, such as elevated blood or urine glucose levels, thirst, frequent urination, fatigue or weakness, and blurred vision. If the protease inhibitor indinavir is prescribed, you'll also require periodic monitoring for crystalluria, hematuria, hemolytic anemia, and hepatitis. Indinavir is contraindicated if you're pregnant or breastfeeding. Contact your healthcare provider immediately if you develop a rash, fever, back or abdominal pain, dysuria, hematuria, or signs and symptoms of hyperglycemia such as polydipsia or polyuria.
It's important that you complete the prescribed regimen. Many people who start an HIV PEP regimen don't complete it because of adverse reactions such as nausea and diarrhea. Antimotility and antiemetic drugs or medications that target specific symptoms can help you manage adverse reactions and stay on the prescribed regimen. If adverse reactions become intolerable, discuss them with your healthcare provider, who may be able to modify the regimen.
If you have antibodies to HBV (a positive HBsAb test), you aren't considered at risk for infection, regardless of test results on the source patient, so PEP isn't indicated. Appropriate PEP should be initiated if you're susceptible to HBV infection and the source patient tests positive for HBsAb, HBeAg, or immunoglobulin M (IgM) antibody to hepatitis B core antigen (HBcAb IgM). You'll be offered hepatitis B immune globulin (HBIG) and the HBV vaccine, both of which can safely be given if you're pregnant or breastfeeding. HBIG is most effective when given within 24 hours of exposure and offers immediate passive protection. If the source patient's results aren't available within 24 hours but he's at high risk for HBV and you're susceptible, HBIG may be administered as a safeguard because it rarely causes serious adverse reactions. However, people with a history of anaphylactic reaction to human Ig preparations shouldn't receive HBIG.
HIV PEP and an effective HBV vaccine are available, but what about prevention or treatment for hepatitis C? Unfortunately, there's no vaccine against HCV and no available treatment after an exposure that will prevent infection. Neither Ig nor antiviral therapy is recommended after exposure.
So how should you follow up after an exposure?
During the follow-up period after exposure to HIV, especially the first 12 weeks when most infected persons are expected to show signs of infection, you shouldn't donate blood, semen, or organs and you should avoid sexual intercourse. If you choose to engage in sex, then using a condom consistently and correctly may reduce the risk of transmission. Women should consider not breastfeeding during the follow-up period to prevent the possibility of exposing their infant to HIV that may be in breast milk.
Because the HBV vaccine is highly effective in both preventing the virus and postexposure if you haven't previously received the series of HBV vaccines, the CDC doesn't recommend routine follow-up treatment. However, any symptoms suggesting hepatitis (such as jaundiced sclera or skin, loss of appetite, nausea, vomiting, fever, and stomach or join pain) should be reported to your healthcare provider. If you've received postexposure treatment, it's unlikely that you'll become infected and pass the infection on to others, so no precautions are recommended as long as you remain symptom free. You shouldn't donate blood, organs, tissues, or semen for 6 months.
If you've been exposed to HCV, you should be tested for HCV antibody and liver enzyme levels as soon as possible after the exposure and then again at intervals designated by your facility's policy: usually at 6 weeks, 12 weeks, 6 months, and 1 year postexposure. Again, any symptoms of hepatitis should be reported to your healthcare provider. Because the risk of becoming infected and passing the infection on to others after an exposure to HCV is low, no precautions are recommended.
We know that bloodborne pathogens can cause serious consequences for healthcare workers who are exposed to them, but such exposures can also have a significant financial impact on the healthcare facility. According to the American Hospital Association (AHA), one case of serious infection can add up to $1 million or more in expenditures for testing follow-up, lost time, and disability payments. And even when no infection occurs, the AHA adds that the cost of follow-up for a high-risk exposure can exceed $3,000 per injury.
There have been several research studies published that address the high cost of managing blood and body fluid exposure in the workplace. One such study gathered data for analysis from 31 exposure scenarios that occurred in four different hospitals. The result? The overall range of costs to manage reported exposures was $71 to $4,838. Nearly every study concluded that management of occupational exposures to blood and potentially infectious body fluids is costly; the best way to avoid these costs is to prevent exposures.
Can we prevent all accidental injuries? The answer is no. You can't help that your adolescent patient jerks his arm away while you're giving him an injection and the needle penetrates your hand after falling from his arm. But by anticipating a child's possible fear of needles, you can take an extra few minutes to reassure him and prepare him as much as possible for what will take place. If you work in the pediatric arena, ask the patient's parent to assist you while you administer an injection to a young child. In addition, many of our older patients may be fearful or confused or may not understand the treatment you're administering. Having a family member or care partner assist you in reassuring and comforting your older patient may make the procedure go more smoothly.
Preventing occupational exposure can prevent occupational infections. That means using appropriate barriers, such as gloves, gowns, and eye protection, as appropriate; safely handling needles and other sharp instruments; and using devices with safety features. Many hospitals and healthcare facilities have already implemented policies and procedures designed to protect us, such as prohibiting the practice of recapping needles, supplying only syringes and needles with safety devices, and installing sharps disposal containers that prohibit overfilling. Some institutions have these containers exchanged for new ones when the contents reach the half to three-quarter full level.
Keeping focused on the task at hand when administering and disposing of needles and sharps will help prevent accidental injuries. For surgical nurses and technicians, extra care should be taken to ensure minimal interruptions during surgical procedures. Limit the number of times the OR door is opened and closed and deliver only urgent messages to the operating surgeon. Why? Because every time the OR door is opened, the surgeon and his assistant may lift their heads and take their eyes off the suturing or surgical instrument they're using. Most hospital exposures occur in the OR because that's where most needles and sharps are used. Faithfully observing the neutral zone where instruments and needles are placed after use will also minimize accidental injuries.
The CDC, in its 2008 "Workbook for Designing, Implementing, and Evaluating a Sharps Injury Prevention Program," states that an effective sharps injury prevention program includes several components that must work in concert to prevent healthcare personnel from suffering needle sticks and other sharps-related injuries. A prevention program should be integrated into existing performance improvement, infection prevention and control, and safety programs. To this end, the CDC has published the five steps it has deemed crucial to sharps injury prevention programs:
* develop an institution-wide culture of safety in the work environment
* promote reporting of sharps injuries and injury hazards
* analyze sharps injury data for prevention planning
* select and evaluate sharps injury prevention devices
* educate and train healthcare personnel.
This last step can be vitally important in preventing blood and body fluid exposure. For example, one Washington State hospital instituted a total health and safety program that showed a 53% drop in workers' compensation and related costs in its first year of the pilot program, with a 30% decrease in the number of needle sticks as a result of mandatory bloodborne pathogen training for all appropriate personnel. In my own practice in infection prevention and control, some of the exposures from needle-stick injuries have been a direct result of nurses using new products that have safety devices with which they're unfamiliar. If you've missed the in-service on a new product, seek instruction from your manager or clinical educator so you can feel comfortable and confident using the correct technique.
OSHA has published its suggestions for prevention of sharps injuries:
* eliminate the use of needle devices where practical
* promote safety awareness
* plan for safe handling and disposal of used needles and sharps
* prohibit recapping and bending needles
* analyze injuries to identify hazards and trends.
APIC also reiterates the importance of taking precautions during procedures, when cleaning used instruments or emptying bodily fluid containers, and when handling sharp instruments after use.
Although we've discussed sharps injuries almost exclusively here, don't forget that contamination via mucous membrane exposure may also occur. If you're emptying a collection device containing potentially infectious body fluids, remember to use the proper personal protective equipment (PPE) to protect the mucous membranes of your eyes, nose, and mouth and any nonintact skin such as open cuts on your hands. This means implementing standard precautions for all patients, all the time, in all places.
Safety is key in the prevention of blood and body fluid exposure and avoiding the necessary follow-up such an exposure may require. Use the utmost care in handling needles, sharps, and potentially infectious body fluids; wear appropriate PPE as needed; anticipate the special needs of your patient; and follow your facility's policies on proper disposal of potentially infectious body fluids and sharps. By following the three A's-awareness, attention, and anticipation-and encouraging compliance with your facility's safety program for the prevention of blood and body fluid exposure, you can protect yourself and prevent the accidental transmission of bloodborne pathogens.
1. HIV binds to the T cell.
2. Viral RNA is released into the host cell.
3. The viral RNA is converted into viral DNA through a process called reverse transcriptase. During this process, an enzyme reads the sequence of viral RNA nucleic acids that have entered the host cell and transcribes the sequence into a complementary DNA sequence.
4. Viral DNA enters the T cell's nucleus and inserts itself into the T cell's DNA.
5. The T cell begins to make copies of the RNA components.
6. The enzyme protease helps create new virus particles (virions).
7. The new HIV virion is released from the T cell.
Blood and any visibly bloody body fluids are considered potentially infectious under OSHA guidelines. Other potentially infectious body fluids include:
* semen and vaginal secretions
* cerebrospinal fluid
* synovial fluid
* pleural fluid
* peritoneal fluid
* pericardial fluid
* amniotic fluid.
Materials that aren't considered potentially infectious include feces, urine, vomitus, nasal secretions, saliva (except during dental procedures), sputum, sweat, and tears.
Source: United States Department of Labor. OSHA Standard 29 CFR. Bloodborne Pathogens-1910.1030. http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=100.
Most people who are exposed to blood or other potentially infectious body fluids don't develop an infection. The type of exposure, the amount of blood or body fluid involved, and the viral load in the source patient's blood all affect risk. If the source patient isn't infected with a bloodborne pathogen, only superficial wound care may be needed after a needle stick or sharps injury. Here's how the risks of disease transmission compare for three bloodborne pathogens.
* HIV transmission. Contracting HIV from accidental occupational exposure is quite rare, as indicated by these seroconversion rates:
- -sharps injury: 0.3%, or about 1 in 300
- -mucous membrane exposure: 0.09%, or about 1 in 1,000
- -exposure to nonintact skin: probably lower than the risk for mucous membrane exposure.
From 1981 to 2006, the CDC documented 57 cases of HIV/AIDS among healthcare personnel following occupational HIV exposure and identified an additional 140 possible cases, including 24 documented and 35 possible cases of occupationally acquired HIV infection among nurses.
* HBV transmission. The risk of a susceptible person developing clinical HBV following exposure ranges from 1% to 30%, depending on the source person's HBV status. Unlike HIV, which breaks down quickly in the environment, HBV can remain infectious on environmental surfaces for over a week, even in dried blood.
OSHA regulations require offering the HBV vaccine to all healthcare workers who may be exposed to blood or other potentially infectious body fluids on the job. These vaccinations have dramatically decreased transmission of HBV via occupational exposure. However, some healthcare workers don't accept the vaccine or complete the vaccine series, and others who are properly vaccinated don't mount an immune response.
* HCV transmission. The risk of HCV transmission after percutaneous exposure is about 1.8%. The virus can remain viable in the environment between 16 hours and 4 days, although HCV transmission via environmental contamination isn't considered a significant risk in healthcare settings, with the possible exception of hemodialysis units. No vaccine has been developed and the predominant HCV strain in the United States is resistant to current antiviral agents.
Sources: CDC. Surveillance of occupationally acquired HIV/AIDS in healthcare personnel, as of December 2006. http://www.cdc.gov/ncidod/dhqp/bp_hcp_w_hiv.html.
Panlilio AL, Cardo DM, Grohskopf LA, Heneine W, Ross CS, U.S. Public Health Service. Updated U.S. Public Health Service guidelines for the management of occupational exposures to HIV and recommendations for postexposure prophylaxis. MMWR Recomm Rep. 2005;54(RR-9):1-17.
U.S. Public Health Service. Updated U.S. Public Health Service Guidelines for the management of occupational exposures to HBV, HCV, and HIV and recommendations for postexposure prophylaxis. MMWR Recomm Rep. 2001;50(RR-11):1-52.
Remember the three A's when preventing accidental exposure to blood and other potentially infectious body fluids:
If you sustain a puncture injury, such as a needle stick, take the following actions immediately:
* Wash the area with soap and water.
* Alert your supervisor/nursing faculty and initiate the injury-reporting system used at your facility.
* Identify the source patient, who may need to be tested for HIV, HBV, and HCV. State laws will determine whether written informed consent must be obtained from the source patient before his testing. Rapid testing should be used if possible if the HIV status of the source patient is unknown because results can be available as soon as 20 minutes.
* Report as quickly as possible to the employee health services, the ED, or other designated treatment facility. This visit should be documented in your confidential medical record.
* Give consent for baseline testing for HIV, HBV, and HCV. Confidential HIV testing can be performed up to 72 hours after the exposure but should be performed as soon as you can give informed consent for baseline testing.
* Get PEP for HIV in accordance with CDC guidelines. Start the prophylaxis medications within 2 hours after exposure. Make sure that you're being monitored for symptoms of toxicity. Practice safe sex until follow-up testing is complete. Continue the HIV medications for 4 weeks.
* Follow up with postexposure testing at 1 month, 3 months, and 6 months, and perhaps 1 year.
* Document the exposure in detail for your own records, as well as for your employer.
You may find these online resources helpful:
APIC. Prevent needlesticks. http://www.apic.org/AM/Template.cfm?Section=Search§ion=Brochures&template=/C.
CDC. Bloodborne infectious diseases: HIV/AIDS, hepatitis B virus, and hepatitis C virus. http://www.cdc.gov/niosh/topics/bbp/.
CDC. Exposure to blood: What healthcare personnel need to know. http://www.cdc.gov/ncidod/dhqp/pdf/bbp/Exp_to_Blood.pdf.
Chiarello L. Proactive planning for sharps safety. Mater Manag Health Care. 2008;17(8):26-30.
Davenport A, Myers F. Protective action after body fluid exposure. Nurs Manage. 2009;40(10):25-30.
Leigh JP, Gillen M, Franks P, et al. Costs of needlestick injuries and subsequent hepatitis and HIV infection. Curr Med Res Opin. 2007;23(9):2093-2105.
OSHA. Bloodborne pathogens and needlestick prevention. http://www.osha.gov/SLTC/bloodbornepathogens/index.html.
O'Malley EM, Scott RD 2nd, Gayle J, et al. Cost of management of occupational exposures to blood and body fluids. Infect Control Hosp Epidemiol. 2007;28(7):774-782.
Oriola S. Make needlestick safety personal-and protect staff. Prevention Strategist. Spring 2008: 24-27.
Pathophysiology Made Incredibly Visual!! Philadelphia, PA: Lippincott Williams & Wilkins; 2008:112-113,152-153.
Smeltzer SC, Bare BG, Hinkle JL, Cheever KH. Brunner & Suddarth's Textbook of Medical-Surgical Nursing. 11th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2008:1818-1821.
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