2 Safety Precautions When Handling Blood Samples

What safety precautions should be taken when handling blood samples?

Wear gloves : Disposable nitrile gloves should be worn at all times when handling human material in the laboratory. This is particularly important when handling higher risk samples. If gloves become punctured or grossly contaminated, they should be removed and disposed of, hands washed and clean gloves put on.

How should blood specimen be handled?

Avoiding Common Problems – Careful attention to routine procedures can eliminate most of the potential problems related to specimen collection. Materials provided by the laboratory for specimen collection can maintain the quality of the specimen only when they are used in strict accordance with the instructions provided.

  • Please examine specimen collection and transportation supplies to be sure they do not include expired containers,
  • Label a specimen correctly and provide all pertinent information required on the test request form. (See Blood Specimens: Chemistry and Hematology − Blood Collection/Transport Containers,)
  • Submit a quantity of specimen sufficient to perform the test and avoid a QNS (quantity not sufficient), as indicated in the test requirements. (See Quantity Not Sufficient.)
  • Use the container/tube indicated in the test requirements for appropriate specimen preservation.
  • Follow patient instructions prior to specimen collection Including the proper order of blood draw when multiple tubes are required. ( See Blood Specimens: Chemistry and Hematology – Consideration for Single and Multiple Sample Collection.)
  • Carefully tighten specimen container lids to avoid leakage and/or potential contamination of specimens.
  • Maintain and transport the specimen at the temperature indicated in the test requirements.
  • Mix specimen with additive immediately after collection by inverting 5-10 times.

Serum Preparation. The most common serum preparation considerations:

  • Separate serum from red cells within two hours of venipuncture.
  • Mix by inverting specimen with additive immediately after collection.
  • Allow specimens collected in a clot tube (eg, red-top or gel-barrier tube) to clot before centrifugation. (See Blood Specimens: Chemistry and Hematology − Preparing Serum on clotting and gel-barrier tubes and red-top tubes.)
  • Avoid hemolysis: red blood cells broken down and components spilled into serum. Causes and prevention are discussed under the section on hemolysis.
  • Avoid lipemia: cloudy or milky serum sometimes due to the patient’s diet (discussed under the section on lipemia).

Plasma Preparation. The most common considerations in the preparation of plasma:

  • Collect specimen in additive indicated in the test requirements.
  • Mix specimen with additive immediately after collection by inverting 5-10 times.
  • Avoid hemolysis or red blood cell breakdown.
  • Fill the tube completely, thereby avoiding a dilution factor excessive for total specimen volume (QNS).
  • Separate plasma from cells within two hours of venipuncture or as indicated in the test requirements.
  • Label transport tubes as “plasma”
  • Indicate type of anticoagulant (eg, “EDTA,” “citrate,” etc)

Urine Collection. The most common urine collection considerations:

  • Obtain a clean-catch, midstream specimen.
  • Store unpreserved specimens refrigerated or in a cool place until ready for transport.
  • Provide patients with instructions for 24-hour urine collection(s).
  • Add the preservative (as specified in the test requirements) to the urine collection container prior to collection of the specimen if the preservative is not already in the container.
  • Provide sufficient quantity of specimen to meet the minimum fill line on preservative transport container.
  • Provide the proper mixing of specimen with urine preservative as specified in the test requirements.
  • Use the collection container as specified in the test requirements, and refrigerate the specimen when bacteriological examination of the specimen is required.
  • Carefully tighten specimen container lids to avoid leakage of specimen.
  • Divide specimen into separate containers for tests with such requirements.
  • Provide a complete 24-hour collection/aliquot or other timed specimen.
  • Provide a 24-hour urine volume when an aliquot from the 24-hour collection is submitted.
  • Preservatives vary for each test; refer to test information for the required preservative.

What are two safety precautions needed when blood is removed from this person?

SAFETY AND INFECTION CONTROL – Because of contacts with sick patients and their specimens, it is important to follow safety and infection control procedures. PROTECT YOURSELF

  • Practice universal precautions:
    • Wear gloves and a lab coat or gown when handling blood/body fluids.
    • Change gloves after each patient or when contaminated.
    • Wash hands frequently.
    • Dispose of items in appropriate containers.
  • Dispose of needles immediately upon removal from the patient’s vein. Do not bend, break, recap, or resheath needles to avoid accidental needle puncture or splashing of contents.
  • Clean up any blood spills with a disinfectant such as freshly made 10% bleach.
  • If you stick yourself with a contaminated needle:
    • Remove your gloves and dispose of them properly.
    • Squeeze puncture site to promote bleeding.
    • Wash the area well with soap and water.
    • Record the patient’s name and ID number.
    • Follow institution’s guidelines regarding treatment and follow-up.
    • NOTE: The use of post-exposure prophylaxis following blood exposure to HIV has shown effectiveness (about 79%) in preventing seroconversion

PROTECT THE PATIENT

  • Place blood collection equipment away from patients, especially children and psychiatric patients.
  • Practice hygiene for the patient’s protection. When wearing gloves, change them between each patient and wash your hands frequently. Always wear a clean lab coat or gown.

What are 3 safety precautions you can take before entering the lab?

Wear Your PPE and Proper Lab Attire – Lab coat, gloves, eye protection, and appropriate attire should be worn at all times in the lab.

Long pants and shoes completely covering the top of the foot should be worn at all times when working in the lab. Lab coats will protect your clothes and your skin from splashes, spills, or other exposures to chemical or biological agents, and flames in some cases. Safety glasses or goggles will protect your eyes from physical of chemical harm. Skin will heal after minor burns or lacerations but your eyes will not. Eyes are fragile and safety glasses take about three seconds to put on, an eye injury can be permanent. Gloves protect your skin from hazardous materials your hands may come into contact with. However exposure can occur when removing gloves and disposing of them. Follow the steps in the video below to properly remove any gloves used in the lab.

What are the hazards of blood sample collection?

The site from where your blood is drawn could become infected or bruised. A blood draw may be painful and can make you faint. The possible risks associated with blood drawing are pain, bleeding, fainting, bruising, infection and/or hematoma (blood clot under the skin) at the injection site.

How should samples and specimens be handled and collected?

Pre-Collection Guidelines – The initial collection of samples for microbiology testing is critical, since errors that occur at this stage cannot be corrected at a later time, and since mistakes require collection of new specimens.

  • Document that proper patient preparation prior to collection of the specimen has been done.
  • A laboratory request form with the following information must accompany the specimen. This aids interpretation of results and reduces the risk of errors.
    • Patient’s name, DOB, hospital number, and ward/department.
    • Type of specimen and the site from which it was obtained.
    • Date and time collected.
    • Diagnosis with history and reasons for request such as returning from abroad (specify country) with diarrhea and vomiting, rash, pyrexia, catheters in situ or invasive devices used, or surgical details regarding post-operative wound infection.
    • Any antimicrobial drug(s) given.
    • Name and number of the clinician who ordered the investigation, as it may be necessary to telephone preliminary results and discuss treatment before the final result is authorized.
  • Hands should be washed before and after specimen collection. In line with standard precautions, appropriate personal protective equipment should be worn when collecting or handling specimens.
  • Specimens should be collected in sterile containers with close fitting lids to avoid contamination and spillage. It is not necessary to collect stool specimens in a sterile container. All specimen containers must be transported in a double-sided, self-sealing polythene bag with one compartment containing the laboratory request form and the other the specimen.
  • Ideally microbiological specimens should be collected before beginning any treatment such as antibiotics or using antiseptics. However, treatment must not be delayed in serious sepsis.
  • Transport medium may be used to preserve micro-organisms during transportation.
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How do you manage a blood test?

  • Stay hydrated and fill your belly
  • – First, ask if your test requires a period of fasting, If it does, try to fast for the minimum time allowed. If it’s 12 hours, book your test for first thing in the morning so you’re only skipping one meal. Most blood tests don’t require fasting so make sure you’re well fed and have had plenty of water. Low blood sugar, a consequence of skipping meals, can contribute to feeling faint, while dehydration lowers the amount of available fluid in your body and can make it more difficult to draw blood. Drinking plenty of water promotes fuller veins and brings them closer to the surface for easier access. Read : Blood-injury-needle phobia | The fight against fainting

    What are two hazards of blood transfusion?

    Risks – Blood transfusions are generally considered safe, but there is some risk of complications. Mild complications and rarely severe ones can occur during the transfusion or several days or more after. More common reactions include allergic reactions, which might cause hives and itching, and fever.

    What type of hazard is blood?

    Human bodily matter – Workers in health care may be exposed to biological hazards through contact with human bodily matter, such as blood, tissue, saliva, mucus, urine and faeces. These substances have a high risk of containing viral or bacterial diseases.

    What precautions should be taken after blood transfusion?

    How long does it take to recover from a blood transfusion? – After your transfusion, your healthcare provider will recommend that you rest for 24 to 48 hours. You’ll also need to call and schedule a follow-up visit with your healthcare provider.

    What precautions to be taken when you are exposed to blood and body fluids?

    What should you do if you’re exposed to blood or body fluids? – Here are some steps to take if you are exposed to blood and body fluids.

    Wash your hands immediately after any exposure to blood or body fluids, even if you wear gloves. Flush with water if you get splashed in the eyes, nose, or mouth. Contact your doctor right away for further advice if you are pricked by a needle (needlestick).

    Current as of: October 31, 2022 Author: Healthwise Staff Medical Review: William H. Blahd Jr. MD, FACEP – Emergency Medicine & Kathleen Romito MD – Family Medicine & Adam Husney MD – Family Medicine & H. Michael O’Connor MD – Emergency Medicine & W. David Colby IV MSc, MD, FRCPC – Infectious Disease

    Why are safety precautions important when handling real human blood?

    Perspectives in Disease Prevention and Health Promotion Update: Universal Precautions for Prevention of Transmission of Human Immunodeficiency Virus, Hepatitis B Virus, and Other Bloodborne Pathogens in Health-Care Settings, Type 508 Accommodation and the title of the report in the subject line of e-mail.

    Introduction The purpose of this report is to clarify and supplement the CDC publication entitled “Recommendations for Prevention of HIV Transmission in Health-Care Settings” (1).* In 1983, CDC published a document entitled “Guideline for Isolation Precautions in Hospitals” (2) that contained a section entitled “Blood and Body Fluid Precautions.” The recommendations in this section called for blood and body fluid precautions when a patient was known or suspected to be infected with bloodborne pathogens.

    In August 1987, CDC published a document entitled “Recommendations for Prevention of HIV Transmission in Health-Care Settings” (1). In contrast to the 1983 document, the 1987 document recommended that blood and body fluid precautions be consistently used for all patients regardless of their bloodborne infection status.

    This extension of blood and body fluid precautions to all patients is referred to as “Universal Blood and Body Fluid Precautions” or “Universal Precautions.” Under universal precautions, blood and certain body fluids of all patients are considered potentially infectious for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and other bloodborne pathogens.

    Universal precautions are intended to prevent parenteral, mucous membrane, and nonintact skin exposures of health-care workers to bloodborne pathogens. In addition, immunization with HBV vaccine is recommended as an important adjunct to universal precautions for health-care workers who have exposures to blood (3,4).

    Since the recommendations for universal precautions were published in August 1987, CDC and the Food and Drug Administration (FDA) have received requests for clarification of the following issues: 1) body fluids to which universal precautions apply, 2) use of protective barriers, 3) use of gloves for phlebotomy, 4) selection of gloves for use while observing universal precautions, and 5) need for making changes in waste management programs as a result of adopting universal precautions.

    Body Fluids to Which Universal Precautions Apply Universal precautions apply to blood and to other body fluids containing visible blood. Occupational transmission of HIV and HBV to health-care workers by blood is documented (4,5). Blood is the single most important source of HIV, HBV, and other bloodborne pathogens in the occupational setting.

    • Infection control efforts for HIV, HBV, and other bloodborne pathogens must focus on preventing exposures to blood as well as on delivery of HBV immunization.
    • Universal precautions also apply to semen and vaginal secretions.
    • Although both of these fluids have been implicated in the sexual transmission of HIV and HBV, they have not been implicated in occupational transmission from patient to health-care worker.

    This observation is not unexpected, since exposure to semen in the usual health-care setting is limited, and the routine practice of wearing gloves for performing vaginal examinations protects health-care workers from exposure to potentially infectious vaginal secretions.

    Universal precautions also apply to tissues and to the following fluids: cerebrospinal fluid (CSF), synovial fluid, pleural fluid, peritoneal fluid, pericardial fluid, and amniotic fluid. The risk of transmission of HIV and HBV from these fluids is unknown; epidemiologic studies in the health-care and community setting are currently inadequate to assess the potential risk to health-care workers from occupational exposures to them.

    However, HIV has been isolated from CSF, synovial, and amniotic fluid (6-8), and HBsAg has been detected in synovial fluid, amniotic fluid, and peritoneal fluid (9-11). One case of HIV transmission was reported after a percutaneous exposure to bloody pleural fluid obtained by needle aspiration (12).

    • Whereas aseptic procedures used to obtain these fluids for diagnostic or therapeutic purposes protect health-care workers from skin exposures, they cannot prevent penetrating injuries due to contaminated needles or other sharp instruments.
    • Body Fluids to Which Universal Precautions Do Not Apply Universal precautions do not apply to feces, nasal secretions, sputum, sweat, tears, urine, and vomitus unless they contain visible blood.
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    The risk of transmission of HIV and HBV from these fluids and materials is extremely low or nonexistent. HIV has been isolated and HBsAg has been demonstrated in some of these fluids; however, epidemiologic studies in the health-care and community setting have not implicated these fluids or materials in the transmission of HIV and HBV infections (13,14).

    1. Some of the above fluids and excretions represent a potential source for nosocomial and community-acquired infections with other pathogens, and recommendations for preventing the transmission of nonbloodborne pathogens have been published (2).
    2. Precautions for Other Body Fluids in Special Settings Human breast milk has been implicated in perinatal transmission of HIV, and HBsAg has been found in the milk of mothers infected with HBV (10,13).

    However, occupational exposure to human breast milk has not been implicated in the transmission of HIV nor HBV infection to health-care workers. Moreover, the health-care worker will not have the same type of intensive exposure to breast milk as the nursing neonate.

    • Whereas universal precautions do not apply to human breast milk, gloves may be worn by health-care workers in situations where exposures to breast milk might be frequent, for example, in breast milk banking.
    • Saliva of some persons infected with HBV has been shown to contain HBV-DNA at concentrations 1/1,000 to 1/10,000 of that found in the infected person’s serum (15).

    HBsAg-positive saliva has been shown to be infectious when injected into experimental animals and in human bite exposures (16-18). However, HBsAg-positive saliva has not been shown to be infectious when applied to oral mucous membranes in experimental primate studies (18) or through contamination of musical instruments or cardiopulmonary resuscitation dummies used by HBV carriers (19,20).

    Epidemiologic studies of nonsexual household contacts of HIV-infected patients, including several small series in which HIV transmission failed to occur after bites or after percutaneous inoculation or contamination of cuts and open wounds with saliva from HIV-infected patients, suggest that the potential for salivary transmission of HIV is remote (5,13,14,21,22).

    One case report from Germany has suggested the possibility of transmission of HIV in a household setting from an infected child to a sibling through a human bite (23). The bite did not break the skin or result in bleeding. Since the date of seroconversion to HIV was not known for either child in this case, evidence for the role of saliva in the transmission of virus is unclear (23).

    Another case report suggested the possibility of transmission of HIV from husband to wife by contact with saliva during kissing (24). However, follow-up studies did not confirm HIV infection in the wife (21). Universal precautions do not apply to saliva. General infection control practices already in existence – including the use of gloves for digital examination of mucous membranes and endotracheal suctioning, and handwashing after exposure to saliva – should further minimize the minute risk, if any, for salivary transmission of HIV and HBV (1,25).

    Gloves need not be worn when feeding patients and when wiping saliva from skin. Special precautions, however, are recommended for dentistry (1). Occupationally acquired infection with HBV in dental workers has been documented (4), and two possible cases of occupationally acquired HIV infection involving dentists have been reported (5,26).

    • During dental procedures, contamination of saliva with blood is predictable, trauma to health-care workers’ hands is common, and blood spattering may occur.
    • Infection control precautions for dentistry minimize the potential for nonintact skin and mucous membrane contact of dental health-care workers to blood-contaminated saliva of patients.

    In addition, the use of gloves for oral examinations and treatment in the dental setting may also protect the patient’s oral mucous membranes from exposures to blood, which may occur from breaks in the skin of dental workers’ hands. Use of Protective Barriers Protective barriers reduce the risk of exposure of the health-care worker’s skin or mucous membranes to potentially infective materials.

    1. For universal precautions, protective barriers reduce the risk of exposure to blood, body fluids containing visible blood, and other fluids to which universal precautions apply.
    2. Examples of protective barriers include gloves, gowns, masks, and protective eyewear.
    3. Gloves should reduce the incidence of contamination of hands, but they cannot prevent penetrating injuries due to needles or other sharp instruments.

    Masks and protective eyewear or face shields should reduce the incidence of contamination of mucous membranes of the mouth, nose, and eyes. Universal precautions are intended to supplement rather than replace recommendations for routine infection control, such as handwashing and using gloves to prevent gross microbial contamination of hands (27).

    Take care to prevent injuries when using needles, scalpels, and other sharp instruments or devices; when handling sharp instruments after procedures; when cleaning used instruments; and when disposing of used needles. Do not recap used needles by hand; do not remove used needles from disposable syringes by hand; and do not bend, break, or otherwise manipulate used needles by hand. Place used disposable syringes and needles, scalpel blades, and other sharp items in puncture-resistant containers for disposal. Locate the puncture-resistant containers as close to the use area as is practical. Use protective barriers to prevent exposure to blood, body fluids containing visible blood, and other fluids to which universal precautions apply. The type of protective barrier(s) should be appropriate for the procedure being performed and the type of exposure anticipated. Immediately and thoroughly wash hands and other skin surfaces that are contaminated with blood, body fluids containing visible blood, or other body fluids to which universal precautions apply. Glove Use for Phlebotomy

    Gloves should reduce the incidence of blood contamination of hands during phlebotomy (drawing blood samples), but they cannot prevent penetrating injuries caused by needles or other sharp instruments. The likelihood of hand contamination with blood containing HIV, HBV, or other bloodborne pathogens during phlebotomy depends on several factors: 1) the skill and technique of the health-care worker, 2) the frequency with which the health-care worker performs the procedure (other factors being equal, the cumulative risk of blood exposure is higher for a health-care worker who performs more procedures), 3) whether the procedure occurs in a routine or emergency situation (where blood contact may be more likely), and 4) the prevalence of infection with bloodborne pathogens in the patient population.

    The likelihood of infection after skin exposure to blood containing HIV or HBV will depend on the concentration of virus (viral concentration is much higher for hepatitis B than for HIV), the duration of contact, the presence of skin lesions on the hands of the health-care worker, and – for HBV – the immune status of the health-care worker.

    Although not accurately quantified, the risk of HIV infection following intact skin contact with infective blood is certainly much less than the 0.5% risk following percutaneous needlestick exposures (5). In universal precautions, all blood is assumed to be potentially infective for bloodborne pathogens, but in certain settings (e.g., volunteer blood-donation centers) the prevalence of infection with some bloodborne pathogens (e.g., HIV, HBV) is known to be very low.

    Some institutions have relaxed recommendations for using gloves for phlebotomy procedures by skilled phlebotomists in settings where the prevalence of bloodborne pathogens is known to be very low. Institutions that judge that routine gloving for all phlebotomies is not necessary should periodically reevaluate their policy.

    Gloves should always be available to health-care workers who wish to use them for phlebotomy. In addition, the following general guidelines apply:

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    Use gloves for performing phlebotomy when the health-care worker has cuts, scratches, or other breaks in his/her skin. Use gloves in situations where the health-care worker judges that hand contamination with blood may occur, for example, when performing phlebotomy on an uncooperative patient. Use gloves for performing finger and/or heel sticks on infants and children. Use gloves when persons are receiving training in phlebotomy. Selection of Gloves The Center for Devices and Radiological Health, FDA, has responsibility for regulating the medical glove industry. Medical gloves include those marketed as sterile surgical or nonsterile examination gloves made of vinyl or latex. General purpose utility (“rubber”) gloves are also used in the health-care setting, but they are not regulated by FDA since they are not promoted for medical use. There are no reported differences in barrier effectiveness between intact latex and intact vinyl used to manufacture gloves. Thus, the type of gloves selected should be appropriate for the task being performed. The following general guidelines are recommended:

    Use sterile gloves for procedures involving contact with normally sterile areas of the body. Use examination gloves for procedures involving contact with mucous membranes, unless otherwise indicated, and for other patient care or diagnostic procedures that do not require the use of sterile gloves. Change gloves between patient contacts. Do not wash or disinfect surgical or examination gloves for reuse. Washing with surfactants may cause “wicking,” i.e., the enhanced penetration of liquids through undetected holes in the glove. Disinfecting agents may cause deterioration. Use general-purpose utility gloves (e.g., rubber household gloves) for housekeeping chores involving potential blood contact and for instrument cleaning and decontamination procedures. Utility gloves may be decontaminated and reused but should be discarded if they are peeling, cracked, or discolored, or if they have punctures, tears, or other evidence of deterioration.

    Waste Management Universal precautions are not intended to change waste management programs previously recommended by CDC for health-care settings (1). Policies for defining, collecting, storing, decontaminating, and disposing of infective waste are generally determined by institutions in accordance with state and local regulations.

    • Information regarding waste management regulations in health-care settings may be obtained from state or local health departments or agencies responsible for waste management.
    • Reported by: Center for Devices and Radiological Health, Food and Drug Administration.
    • Hospital Infections Program, AIDS Program, and Hepatitis Br, Div of Viral Diseases, Center for Infectious Diseases, National Institute for Occupational Safety and Health, CDC.

    Editorial Note: Implementation of universal precautions does not eliminate the need for other category- or disease-specific isolation precautions, such as enteric precautions for infectious diarrhea or isolation for pulmonary tuberculosis (1,2). In addition to universal precautions, detailed precautions have been developed for the following procedures and/or settings in which prolonged or intensive exposures to blood occur: invasive procedures, dentistry, autopsies or morticians’ services, dialysis, and the clinical laboratory.

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    *The August 1987 publication should be consulted for general information and specific recommendations not addressed in this update. **The August 1987 publication should be consulted for general information and specific recommendations not addressed in this update.

    Copies of this report and of the MMWR supplement entitled Recommendations for Prevention of HIV Transmission in Health-Care Settings published in August 1987 are available through the National AIDS Information Clearinghouse, P.O. Box 6003, Rockville, MD 20850. Disclaimer All MMWR HTML documents published before January 1993 are electronic conversions from ASCII text into HTML.

    This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S.