Infection Control and Defense Mechanisms

Control of Spread of Infection

• Nosocomial infections are hospital-acquired infections that arise from healthcare delivery. Clients are at increased risk.
• Nosocomial infections lead to higher healthcare costs, longer hospital stays, and longer recovery times.
• Most nosocomial infections spread through direct contact between healthcare workers and clients.

Why Patients Get Infections in Hospitals

• Patients with illnesses or diseases have lower resistance to infectious microorganisms.
• Patients in hospitals are exposed to a larger variety of disease-causing organisms.

Four Body Defenses Against Infections

• Mechanical Defenses: Skin (epidermis, sebaceous glands, dryness), eyes (lacrimal glands), saliva (cleansing action), respiratory tract (mucus, ciliated epithelium), and urinary tract (flushing action). These are the first line of defense.
• Physiological Defenses: Inflammation (pus formation), fever (above 38°C to 40°C), and phagocytosis (ingestion of bacteria or foreign material by immune cells).
• Chemical Defenses: Enzymes, sebaceous glands (oily substance that lowers skin pH), and gastric juice.
• Immunity: The body's ability to destroy and resist infection. It fights against pathogens. This system has two types: natural and acquired/vaccine-mediated (passive/maternal, active/infection). The latter further has artificial types: passive and active.

Principles of Basic Infection Control

• Microorganisms move through the air.
• Microorganisms transfer when surfaces touch (a clean item touching a dirty item makes the clean item dirty). Avoid passing dirty items over clean items.
• Microorganisms move via gravity when one item is above another.

Principles of Basic Infection Control (Continued)

• Microorganisms released into the air (droplet nuclei) when breathing or speaking. Avoid breathing directly in someone's face; cover your mouth when coughing/sneezing.
• Microorganisms move slowly on dry surfaces but rapidly on moist surfaces. Using paper towels to turn off faucets, dry surfaces before returning items to bedside.
• Proper handwashing removes many microorganisms that can transfer between items. Always wash hands between patients.

Standard Precautions of Infection Control

• Standard precautions prevent transmission of diseases caused by contact with blood, body fluids, non-intact skin (rashes), and mucous membranes.
• These precautions apply to all patients, whether or not they appear infectious or symptomatic.
• Standard precautions include practices like hand hygiene, respiratory hygiene (cough etiquette), medical waste disposal, safe injection practices, and cleaning.

Hand Hygiene (Proper Hand Washing)

• Handwashing is the most important procedure for preventing microorganism transfer and nosocomial infections.
• The CDC recommends 10-15 seconds of handwashing to remove most transient organisms.

When Should Hands Be Washed?

• When visibly soiled
• Before and after patient contact
• After contact with a source of microorganisms (blood, body fluids, etc.) or contaminated items
• Before invasive procedures and after removing gloves
• At the beginning and end of each workday

Respiratory Hygiene and Cough Etiquette

• Persons with respiratory symptoms should practice source control measures, not just in the patient but also in the healthcare facility.
• Cover mouth and nose when coughing or sneezing, use tissues, and properly dispose of tissues and masks.
• Patients with respiratory symptoms should be kept at least one meter away from others in common areas.
• Post visible alerts at entrances about respiratory hygiene.
• Make hand hygiene resources, tissues, and masks available in common areas.

Medical Waste Disposal

• Sharps (puncture-resistant, leak-proof, closable containers) should be disposed of immediately after use in designated containers.
• Items and containers should be labeled with biohazard symbols or red color.
• Syringes or collection tubes with needles are discarded with the needle still attached.
• Non-sharp items saturated or with dripping fluids should be put in biohazard disposal bags.

Medical Waste Segregation Chart

• Different types of medical waste are color-coded for proper disposal based on the specific material, such as sharps (red), biohazard (red), trace (yellow), chemicals (blue), and radioactive (silver/gray).

Safe Injection Practices

• Use a new needle and syringe every time a medication vial or IV bag is accessed.
• Use a new needle and syringe with each patient injection.
• Use medication vials for only one patient.

Cleaning

• Cleaning reduces contaminants.
• Disinfection removes most pathogens.
• Sterilization kills all organisms.

Assess your understanding of infection control, defense mechanisms, and how the body responds to pathogens. Explore the roles of mechanical and chemical defenses in preventing infection. Test your knowledge of nosocomial infections and physiological responses like fever.