Infection control and Isolation.
Learning Objective
Examine the elements of chain of infection and the body's defenses
Describe the manifestations of the inflammatory response
Differentiate between local and systemic infections and related diagnostic tests
Relate principles of medical and surgical asepsis and their application to client care
Differentiate between standard precautions and various types of isolation precautions
Identify nursing interventions that can protect against infection
Chain of Infection
Definition: In order for infection to spread from one person to another, a chain of events known as the chain of infection must occur.
Example Illustrating the Chain of Infection:
A nurse caring for eight patients in a hospital unit on a hectic day.
The nurse assists a CNA in changing the linens in the room of Patient One, hospitalized for severe diarrhea caused by Clostridium difficile (C. Diff).
The nurse wears gloves, but there is a tiny hole in them, leading to contamination during perineal care.
After removing the gloves with no hand hygiene, the nurse prepares oral medications in Room Two.
Patient Two receives the oral medication and later develops C. Diff due to exposure.
Elements of the Chain of Infection:
Infectious Agent: C. Diff
Reservoir: Patient One
Portal of Exit: Bowel movements of Patient One
Mode of Transmission: Nurse's hands (C. Diff is not killed by hand sanitizer, only by washing hands)
Portal of Entry: Patient Two's mouth
Susceptible Host: Patient Two
Types of Infections
Local Infections:
Confined to one area, usually mild.
Treated with topical or oral antibiotics.
Examples: Pneumonia, urinary tract infection (UTI).
Symptoms: Symptoms are limited to the site of infection, e.g.,
Pneumonia Symptoms: Cough, difficulty breathing, crackles in lower lung bases.
Systemic Infections:
Life-threatening, spread throughout the entire bloodstream affecting the whole body.
Treated with IV antibiotics, requires close monitoring due to rapid deterioration potential.
Example: Sepsis (infection of the bloodstream).
Defenses Against Infection
Primary Defenses:
Intact Skin: Breaks or cuts increase infection risk (e.g., pressure sores).
Mucous Membranes: Produce mucus to trap pathogens, helping expel them from respiratory or urinary tracts.
GI Tract Flora: Normal bacteria help prevent infections.
Secondary Defenses:
Inflammatory Process: Activation of immune response, leading to increased blood flow and white blood cell activity at infection sites.
Elevated Temperature: Fever (above 101°F) creates an environment unfavorable for many microorganisms to live and multiply.
Complement Cascade: Specialized proteins released when pathogens are detected, rupturing bacterial cell membranes.
Factors Affecting Body's Defenses Against Infection
Age: Younger children and older adults have weaker immune systems, increasing infection risk.
Chemical Exposure: Toxicity can impair immune defenses.
Chronic Illness: Frequent immune responses can weaken immune reserves.
Lifestyle Factors:
Lack of exercise and rest decreases defenses.
Increased stress can lead to higher susceptibility.
Poor nutrition reduces necessary vitamins and nutrients for immune function.
High-Risk Populations for Infection
Individuals with:
HIV/AIDS (lowered immunity)
Certain malignancies (cancer)
Organ transplant recipients (immunosuppressants)
Patients on corticosteroids or gastric suppressants
Those who have undergone radiation therapy or have indwelling devices.
Diagnostic Tests for Infection
Common Tests:
Urinalysis: Checks for white blood cells in urine for UTIs.
Culture and Sensitivity Tests: Identify bacteria causing the infection.
Chest X-Ray: Confirms pneumonia or atelectasis in respiratory infections.
Throat Cultures: Swabbing for strep throat diagnosis.
Blood Tests:
White Blood Cell Count: Assesses infection severity; low counts increase infection risk.
Nonspecific Markers: C-Reactive Protein (CRP), Erythrocyte Sedimentation Rate (ESR), Procalcitonin (PCT).
Infection Control Measures
Hand Hygiene: Primary method in healthcare to prevent infection spread. Important for both staff and patients.
Clean Environment: Ensure cleanliness of nursing stations, patient rooms, and medical equipment.
Standard Precautions
Definition: Practices applied to all patients regardless of diagnosis, ensuring safety and infection control.
Components of Standard Precautions:
Practice good hand hygiene using soap, water, or alcohol-based gel.
Use Personal Protective Equipment (PPE) such as gloves, gowns, masks, and eye protection as appropriate.
Safely dispose of sharps in puncture-resistant containers.
Use respiratory hygiene (covering coughs, disposing of tissues promptly).
Isolation Precautions
Contact Precautions: Used primarily for C. Diff and GI issues.
Requires gowning and gloving before contact, with hand hygiene upon leaving the room. Avoid using alcohol-based hand sanitizers.
Droplet Precautions: Prevent spread of pathogens through respiratory secretions.
Examples: Influenza, Group A Strep, Bacterial Meningitis.
Requires wearing a mask and implementing respiratory hygiene.
Airborne Precautions: Prevent transmission of pathogens like tuberculosis and COVID-19.
Patients require isolation with specially designed ventilation systems to direct air outside.
Conclusion
Understanding infection control is crucial for healthcare providers to manage and prevent the transmission of infections within healthcare settings effectively. Various interventions, precautions, and hygiene practices must be consistently applied to protect both patients and staff.