Safety Practices and Quality in the Hematology Laboratory

Safety Practices and Quality in the Hematology Laboratory

Introduction to Hematology Laboratory Procedures

  • Procedures performed in the hematology laboratory include:
    • Complete Blood Cell Count (CBC): Evaluates the number, morphology, and distribution of cellular constituents of blood.
    • Erythrocyte Count: Red blood cells (RBCs).
    • Leukocyte Count: White blood cells (WBCs).
    • Thrombocyte Count: Platelets (PLTs).
    • Differential: Evaluates the morphology and distribution of leukocytes.
    • Erythrocyte Sedimentation Rate (ESR): Evaluates inflammation.
    • Blood Coagulation Tests: Monitors hemostasis and thrombosis, evaluates clotting and bleeding tendencies, and monitors anticoagulant therapy.
    • Specialized Testing: For confirmation of hematologic disorders.

Functions of the Hematology Laboratory

Role of Personnel
  • Personnel include:
    • Medical laboratory scientists
    • Medical laboratory technicians
    • Laboratory assistants
    • Phlebotomists
  • These personnel are highly trained, having graduated from accredited programs ranging from certificate to doctoral levels.
  • In many states, personnel are certified and may be licensed to practice.
Assays and Examinations
  • Laboratory assays can:
    • Establish or rule out a diagnosis.
    • Confirm a doctor’s clinical impressions of possible hematological disorders.
    • Detect unsuspected disorders through appropriate testing.
    • Monitor the effects of therapy on the patient.
    • Detect minimal residual disease after therapy.

Patient Safety

National Patient Safety Goals
  • The Joint Commission’s National Patient Safety Goals include:
    • Correct Patient Identification: At least two identifiers, which could be the patient’s name, assigned ID number, or date of birth.
    • Improved Staff Communication: Ensuring effective communication about patient issues and critical lab values in a timely manner.
    • Reduction of Hospital-Acquired Infections (HAI): Following CDC and WHO guidelines for handwashing and infection control.

Safety in the Hematology Laboratory

Framework for Safety Standards
  • Safety standards in laboratories are governed by:
    • OSHA (Occupational Safety and Health Administration)
    • CLSI (Clinical and Laboratory Standards Institute)
    • CDC (Centers for Disease Control and Prevention)
    • DHHS (Department of Health and Human Services)
    • CAP (College of American Pathologists)
  • Responsibilities of the safety officer include:
    • Ensuring compliance with regulations affecting the laboratory.
    • Labeling of chemicals and providing supplies for safe handling and disposal of biohazardous materials.
OSHA Acts and Standards
  • OSHA standards include provisions for:
    • Warning Labels: To alert workers to potential hazards.
    • Protective Equipment: Requirements for suitable protective gear.
    • Exposure Control Procedures: Protocols to prevent exposure to hazardous materials.
    • Training Programs: Mandatory training and education for laboratory staff.

Chemical Hygiene Plan

  • Mandated for all clinical laboratories, the Chemical Hygiene Plan (CHP) ensures:
    • Awareness of chemical hazards in the workplace.
    • Compliance with the Hazard Communication Standard (HCS).
    • Adherence to Safety Data Sheets (SDS) outlining safe handling, storage, and disposal of hazardous materials.
    • Alignment with the Globally Harmonized System of Classification and Labeling of Chemicals (GHS).

Occupational Exposure to Bloodborne Pathogens

  • Key regulations by OSHA include:
    • Development and compliance with a safety plan to protect staff from bloodborne pathogens, specifically Hepatitis B Virus (HBV) and Human Immunodeficiency Virus (HIV).
    • Safe management of medical waste.
  • Additional recommendations include:
    • Use of standard precautions as advised by the CDC.
    • Guidelines from CLSI for worker protection against bloodborne pathogens.
    • CDC guidance post-exposure treatment recommendations.

Preventing Transmission of Infectious Diseases

  • Employer mandates include:
    • Educating healthcare workers on standard precautions to prevent bloodborne infections.
    • Provision of necessary equipment and supplies (e.g., gloves).
    • Monitoring compliance with biosafety policies.

Preventing Occupational Transmission of HBV, HCV, and HIV

Occupational Exposure Types
  • Percutaneous Injury: Primary risk for HIV transmission includes:
    • Deep injuries.
    • Late-stage HIV in source patients.
    • Visible blood on the puncture device.
    • Injury involving a needle used on a source patient's artery or vein.
  • Additional influencing factors include:
    • Amount of infected blood in exposure.
    • Duration of contact with infectious material.
    • Viral load of the source patient.
    • Presence of skin lesions or abrasions.
Transmission Risks
  • Risk of Hepatitis B Virus (HBV):
    • Significant decline in risk due to mandatory vaccination for laboratory workers.
    • High viral penetrance; stable in dried blood for up to 7 days at room temperature.
    • Infection risk based on HBe antigen status:
    • Positive: 22% to 30% risk of infection.
    • Negative: 1% to 6% risk of infection.
  • Risk of Hepatitis C Virus (HCV):
    • Less understood, but considered a bloodborne pathogen with approximately 1.8% risk of infection.

Immune Status: Screening and Vaccination

  • Screening procedures for employees include:
    • Tuberculosis testing (PPD skin test).
    • Rubella immunity testing.
    • Hepatitis B surface antigen testing.
  • Vaccination procedures must be implemented for healthcare employees.

Safe Work Practices and Protective Techniques for Infection Control

  • Ensure adherence to a safety manual with established policies and practices.
  • Implement standard precaution measures to prevent occupational exposure to bloodborne pathogens.
  • Maintain rigorous hand hygiene practices.
  • Use appropriate personal protective equipment (PPE) and select gloves carefully for use across procedures.

Handwashing Guidelines

Five Moments of Hand Hygiene
  1. Before Patient Contact: Clean hands to protect the patient from harmful germs.
  2. Before an Aseptic Task: Clean hands immediately prior to the task to prevent infection.
  3. After Body Fluid Exposure Risk: Clean hands post-exposure to body fluids and especially after glove removal.
  4. After Patient Contact: Clean hands after engaging with the patient to maintain a safe environment.
  5. After Contact with Patient Surroundings: Clean hands after touching surfaces around the patient room to protect oneself and the environment.
Recommendations for Hand Hygiene
  • Use non-antimicrobial soap or an antimicrobial soap when visibly soiled.
  • Use alcohol-based antiseptics for routine decontamination if hands are not visibly dirty.
  • Ensure decontamination post-contact with any patient skin, blood, and body fluids or contaminated surfaces.
  • Be familiar with proper use of sanitizers and ensure compliant hand hygiene protocols are observed rigorously.

Guidelines for Using Gloves During Phlebotomy Procedures

  • Gloves must be worn during:
    • Fingersticks or heelsticks for infants and children.
    • Phlebotomy training sessions.
    • All specimen processing tasks.
  • Gloves should be changed between each patient contact to prevent cross-contamination.

Decontamination of Work Surfaces and Equipment

  • Employees should clean surfaces at the beginning and end of shifts with a diluted bleach solution (1:10).
  • Protocols for spill management in clinical settings include:
    • Wearing gloves and laboratory coats.
    • Using disposable towels to absorb liquid blood before decontamination.
    • Utilizing diluted bleach for cleaning and ensuring all disposable materials used for cleanup are discarded in biohazard containers.
  • Nondisposable equipment should be decontaminated by soaking in a dilute bleach solution overnight.

General Infection Control Safety Practices

Essential Practices
  • Ensure all devices that can transmit infection are sterile and non-reusable.
  • Prohibit food and drink in work areas affiliated with specimen handling.
  • Ensure that specimens needing centrifugation are properly capped and placed.
  • Minimize aerosol production during the handling of rubber-stoppered test tubes.
Additional Guidelines
  • Mechanically pipette all clinical materials; mouth pipetting is strictly forbidden.
  • Prohibit the use of tobacco, contact lens adjustments, or makeup application in laboratory settings when working with gloved hands.