Infection Control & Microorganisms Study Guide

NURS 107 PM Sp26 Exam 4 Study Guide Outline Infection Control & Microorganisms

  • Chain of Infection: Understand each component and provide examples of each.

    • Infectious Agent: The pathogen, such as bacteria, viruses, fungi, or parasites that causes disease.

    • Reservoir: The natural habitat of the infectious agent, where it lives and multiplies (e.g., humans, animals, environments).

    • Portal of Exit: The route through which the infectious agent leaves the reservoir (e.g., respiratory tract, gastrointestinal tract, blood).

    • Mode of Transmission: The means by which the infectious agent is transmitted to a new host (e.g., direct contact, droplet transmission, airborne).

    • Portal of Entry: The path through which the infectious agent enters a new host (e.g., mucous membranes, broken skin).

    • Susceptible Host: An individual who is at risk of infection due to factors such as weakened immune systems, age, underlying health issues.

  • Susceptible Hosts:

    • Populations at higher risk for infection include infants, elderly individuals, immunocompromised patients, and chronic illness sufferers.

  • Virulence:

    • Definition: The degree of pathogenicity of an organism, which determines its ability to cause disease.

    • Implications: High virulence correlates with severe disease outcomes, and some microbes may adapt to increase their virulence over time.

  • Stages of Infection: Understand each phase and its characteristics; the most infectious stage is typically the Illness stage.

    • Incubation: Time between exposure and the appearance of symptoms.

    • Prodromal: Early signs and symptoms appear but are not specific.

    • Illness: Disease is fully manifested; the individual is most contagious.

    • Convalescence: Recovery phase where the body gradually returns to health.

  • Healthcare-associated Infections (HAIs):

    • General concepts: Infections contracted during medical treatment or hospitalization.

    • Examples:

    • CLABSI (Central Line-Associated Bloodstream Infection): Infections occurring in a patient with a central venous catheter.

    • CAUTI (Catheter-Associated Urinary Tract Infection): Infections associated with the use of urinary catheters.

    • SSI (Surgical Site Infection): Infections that occur post-surgery at the site of surgical incision.

    • MRSA (Methicillin-Resistant Staphylococcus Aureus): A type of staph infection resistant to many antibiotics.

    • MDROs (Multidrug-Resistant Organisms): Pathogens resistant to multiple types of antibiotics.

  • Food-borne Illnesses:

    • General awareness of common pathogens that cause food-borne illnesses, including:

    • Salmonella, E. coli, Listeria, Norovirus.

  • Transmission:

    • Direct Transmission: Person-to-person contact spreading infectious agents.

    • Indirect Transmission: Involves an intermediate object (fomites) transmitting pathogens.

    • Fomites: Inanimate objects that can carry infectious agents (e.g., doorknobs, utensils).

    • Droplet Transmission: Spread through respiratory droplets produced when an infected individual coughs or sneezes.

    • Airborne Transmission: Involves the transmission of smaller droplets that can remain suspended in the air longer distances.

    • Contact Transmission: Can be either direct or indirect; involves physical interaction or contact with contaminated surfaces.

Standard Precautions & Isolation Standard Precautions

  • Purpose and Application:

    • To prevent the spread of infections in healthcare settings through barrier protection.

  • Hand Hygiene Principles:

    • Handwashing with soap and water or using alcohol-based hand rubs significantly reduces pathogen transmission.

  • Use of PPE:

    • Personal Protective Equipment (PPE) includes gloves, masks, gowns, and face shields designed to protect healthcare workers and patients.

Types of Transmission-Based Precautions

  • Contact Precautions:

    • Used when pathogens are spread by direct or indirect contact; examples include MRSA and VRE.

    • PPE: Gloves and gowns, when entering the room.

  • Droplet Precautions:

    • Used for diseases spread by respiratory droplets; examples include influenza or COVID-19.

    • PPE: Surgical masks when within 6 feet of the patient.

  • Airborne Precautions:

    • Used for diseases that remain suspended in the air; examples include tuberculosis and measles.

    • PPE: N95 respirators or powered air-purifying respirators and negative pressure rooms.

Key PPE Concepts

  • When Masks are Required:

    • Situations when masks must be used include droplet and airborne precautions, or when caring for a patient with known respiratory infections.

  • N95 vs Surgical Masks:

    • N95 masks provide a higher level of filtration compared to surgical masks; N95 is necessary for airborne precautions.

  • Situations Requiring Gowns and Gloves:

    • Gowns and gloves should be worn when there is potential for contact with contaminated surfaces or fluids.

Special Infection Considerations

  • Situations Requiring Soap and Water Hand Hygiene:

    • Instances involving visible soiling, such as in cases of C. difficile infection.

  • Negative Pressure Rooms:

    • Used for patients with diseases transmitted through airborne particles, to prevent pathogen spread outside the room.

  • Diseases Requiring Specific Isolation:

    • Examples include tuberculosis (airborne), MRSA (contact), and viral hemorrhagic fevers (contact/droplet).

Hand Hygiene & Medical vs Surgical Asepsis

  • Difference Between Sterile and Clean Techniques:

    • Medical Asepsis (Clean Technique): Practices aimed at reducing the number of pathogens present; includes hand hygiene and environmental cleaning.

    • Surgical Asepsis (Sterile Technique): Techniques ensuring that no pathogens are present; used during invasive procedures.

Hand Hygiene

  • Situations When Hand Hygiene Must Be Performed:

    • Before patient contact, before aseptic tasks, after contact with body fluids, after patient contact, and after contact with surroundings.

Medical Asepsis

  • Clean Technique:

    • Involves practices like regular handwashing with soap and water and using disinfecting methods for surfaces.

  • Reducing Microorganisms:

    • Utilizes cleaning practices that lessen the microbial load in environments.

  • Environmental Cleaning Practices:

    • Routine cleaning using EPA-approved disinfectants to ensure low numbers of pathogens on surfaces.

Surgical Asepsis

  • Sterile Technique:

    • Procedures that keep areas free from all living microorganisms; essential for surgical and invasive procedures.

  • Situations Requiring Sterile Fields:

    • When performing surgeries, inserting catheters, or during any invasive procedure.

  • Principles of Maintaining Sterility:

    • Include keeping the sterile field uncluttered, only allowing sterile items on it, and being aware of the surroundings constantly.

Skin Structure & Function

  • Skin Layers:

    • Epidermis: The outermost layer, providing a protective barrier.

    • Dermis: Contains connective tissues, blood vessels, and nerve endings; supports the epidermis.

    • Subcutaneous Layer / Hypodermis: Fat and connective tissue that insulates and absorbs shock.

  • Functions of the Skin:

    • Provides protection, regulates temperature, facilitates sensation, and acts as a barrier to pathogens.

Wound Healing & Wound Assessment

Phases of Wound Healing

  • Hemostasis: Initial response, involving clot formation to stop bleeding.

  • Inflammatory Phase: Follows hemostasis, characterized by redness, swelling, heat, and pain.

  • Proliferative Phase: Tissue formation occurs, including the growth of new tissue and blood vessels.

  • Maturation/Remodeling Phase: Development of collagen to strengthen the wound site over time.

Wound Healing Types

  • Primary Intention: Wound healing through direct closure using sutures or staples to approximate edges.

  • Secondary Intention: Healing occurs from the bottom upward; granulation tissue fills the wound.

  • Delayed/Tertiary Intention: Similar to secondary intention, but closure is performed later with sutures or staples after initial healing.

Wound Tissue Types

  • Granulation Tissue: Pink and moist indicating healing; forms new tissue to fill the wound.

  • Necrotic Tissue: Dead tissue needing removal; usually black or brown in color.

  • Eschar: Thick, hard tissue, often black, indicating necrosis.

  • Slough: Soft, yellow tissue that may need to be debrided.

Wound Drainage Types

  • Serous: Clear, watery fluid; indicates normal healing processes.

  • Serosanguineous: Pink, pale red drainage indicating minor bleeding.

  • Sanguineous: Red blood drainage indicating active bleeding.

  • Purulent: Thick, yellow/green drainage indicating infection.

Wound Complications

  • Dehiscence: Partial or total separation of wound edges; increases risk of infection.

  • Evisceration: Protrusion of internal organs through an opened wound.

  • Undermining: Tissue loss under the wound edges.

  • Tunneling: Channels develop within the wound.

  • Sinus Tract: A channel that conveys pus or fluid from a wound to a surface.

  • Fistula: An abnormal connection between two bodily cavities.

Wound Care & Debridement

Debridement Methods

  • Mechanical: Physical removal of dead tissue (e.g., wet-to-dry dressings).

  • Enzymatic: Use of chemical agents to aid in tissue removal.

  • Autolytic: Body’s own enzymes and moisture promote wound healing; semi-occlusive dressings used.

  • Surgical/Sharp: Involves surgical intervention to remove nonviable tissue.

Dressing Types

  • Transparent Film: Protects wounds while allowing for oxygen exchange; used for superficial injuries.

  • Hydrocolloid: Absorbs exudate, maintains a moist environment, and protects from bacteria.

  • Foam: Highly absorbent; used for wounds with significant drainage.

  • Alginates: Derived from seaweed; highly absorbent and forms a gel upon contact with drainage.

Goals of Wound Care & Dressings

  • Prevent Infection: By maintaining a clean environment and dressing.

  • Promote Circulation and Healing: Using appropriate dressings to increase blood flow.

  • Remove Nonviable Tissue: Through appropriate debridement methods to prevent infection.

  • Maintain Proper Moisture Balance: By using moisture-retentive dressings to enhance healing.

Drains & Postoperative Wound Care

Common Surgical Drains

  • Jackson-Pratt (JP) Drain: A closed suction drain that collects fluid; uses a bulb to create suction by compressing.

  • Hemovac: Similar function but has a larger reservoir; uses negative pressure to evacuate fluids. Uses larger tubing as compared to JP; suitable for larger drainage.

Nursing Responsibilities

  • Monitoring Output: Regular checks on volume and characteristics of fluid being drained.

  • Maintaining Suction: Ensuring the device remains compressed; preventing occlusions in tubing.

  • Proper Emptying and Documentation: Empty drains when full (typically every 4-8 hours), and accurately document amount and characteristics of drainage.

Pressure Injuries

Risk Factors

  • Various factors increase the risk for pressure ulcers, including immobility, poor nutrition, moisture, and friction/shear forces.

Pressure Injury Stages

  • Stage I: Non-blanchable redness of intact skin.

  • Stage II: Partial thickness loss of skin presenting as a shallow open wound.

  • Stage III: Full thickness skin loss with visible fat.

  • Stage IV: Full-thickness tissue loss with exposed bone, tendon, or muscle.

  • Deep Tissue Pressure Injury: Persistent non-blanchable deep red, maroon, or purple discoloration.

Prevention Strategies

  • Utilizing pressure-relieving devices and adjusting positions frequently.

  • Ensuring adequate nutrition and hydration to support skin health.

Heat & Cold Therapy

Cold Therapy

  • Physiologic Effects: Decreases inflammation and provides pain control.

  • Indications: Used after injuries to reduce swelling or in chronic pain management.

Heat Therapy

  • Physiologic Effects: Increases circulation, alleviates muscle tension.

  • Indications: Used for muscle spasms, arthritic conditions.

  • Contraindications: Not used in acute injuries or on inflamed areas.

Safety in Healthcare

Fall Prevention

  • Risk Factors: Include age, medications, history of falls, and environmental hazards.

  • Interventions: Regular assessment and modification of environments to promote safety.

Fire Safety

  • RACE Steps:

    • Rescue: Move individuals in danger to safety.

    • Alarm: Activate the fire alarm system.

    • Contain: Close doors to contain the fire.

    • Extinguish: Use a fire extinguisher if safe to do so.

Restraints

  • Understanding Appropriate Use and Nursing Responsibilities:

    • Restraints should be a last resort to ensure patient safety, requiring ongoing assessment and documentation.

Types of Restraints

  • Physical Restraints: Devices or equipment that restrict patient movement.

  • Chemical Restraints: Medications used to control behavior or movement.

Nursing Considerations

  • Patient Monitoring: Regular checks to ensure patient comfort and safety while restrained.

  • Patient Needs While Restrained: Providing necessary needs (hydration, hygiene) and dignity.

  • Risks and Complications: Potential for injury, skin breakdown, and psychological effects.

  • Ethical Considerations: Use should be justified and not used as a punishment; the patient's best interest must always be the priority.

Urinary Catheter Care & Infection Prevention

  • Proper Maintenance: Regular checks to ensure catheter function and patency.

  • Hygiene Practices: Clean technique during catheter insertions and caring for the area around the catheter.

  • Drainage System Management: Importance of maintaining a closed system to reduce infection risk; understanding open vs closed systems.

Pediatric Safety & Safe Sleep

Infant Sleep Safety

  • Safe Sleep Positioning: Infants should always be placed on their backs to sleep, on a firm mattress.

  • Safe Sleep Environment: Keeping the crib free from soft bedding or toys to avoid suffocation risks.

Child Abuse Indicators

  • Physical Findings: Unexplained bruises, fractures, or burns requiring nursing evaluation and reporting per protocols.

Basic Infection Prevention at Home

  • Patient Education Principles for Infection Prevention: Including hand hygiene, food safety, and cleaning practices to ensure health at home.

    • Hygiene Practices: Regular handwashing especially after using the restroom or before meals.

    • Food Safety: Awareness of common food-borne illnesses and methods of prevention.

    • Cleaning Surfaces: Regularly disinfecting areas of high contact to minimize pathogen transmission.

  • Safe Personal Habits:

    • Educate patients on not sharing personal hygiene items and proper food storage to reduce risks of infections.