Infection Control Essentials for NCLEX

The chain of infection consists of six links that must all be present for infection to occur: (1) infectious agent (pathogen), (2) reservoir (where the pathogen lives and multiplies), (3) portal of exit (how the pathogen leaves the reservoir), (4) mode of transmission (how the pathogen travels), (5) portal of entry (how the pathogen enters a new host), and (6) susceptible host (a person vulnerable to infection). Breaking any link in the chain prevents infection transmission. Standard precautions are the foundation of infection control and apply to ALL patients regardless of diagnosis. They include hand hygiene before and after every patient contact, use of gloves when touching blood or body fluids, gowns when clothing may be soiled, masks and eye protection when splashing is possible, safe needle disposal in sharps containers, and proper handling of contaminated equipment and linen. Hand hygiene is the single most effective measure to prevent healthcare-associated infections. Use alcohol-based hand rub (minimum 60% alcohol) for routine decontamination when hands are not visibly soiled. Use soap and water when hands are visibly soiled, after caring for patients with C. difficile (spores are not killed by alcohol), and after using the restroom. Hand hygiene must be performed before and after every patient contact, before donning and after removing gloves, and before any sterile procedure.

Transmission-based precautions are used IN ADDITION to standard precautions when the infection's route of transmission is known or suspected. There are three types: airborne, droplet, and contact precautions. Airborne precautions are for pathogens that remain suspended in the air as tiny particles (5 microns or less) and can travel long distances. Diseases requiring airborne precautions include tuberculosis (TB), measles (rubeola), varicella (chickenpox), and disseminated herpes zoster. Requirements: N95 respirator (fit-tested), negative-pressure airborne infection isolation room (AIIR) with 6-12 air exchanges per hour, and the door must remain closed. Use the mnemonic 'My Chicken Hez TB' to remember airborne diseases. Droplet precautions are for pathogens transmitted through large respiratory particles (greater than 5 microns) that travel only 3-6 feet before falling. Diseases include influenza, pertussis, meningococcal meningitis, rubella, mumps, and diphtheria. Requirements: standard surgical mask within 3-6 feet of the patient, private room preferred but no special ventilation needed. Contact precautions are for pathogens spread by direct or indirect physical contact. Diseases include MRSA, VRE, C. difficile, scabies, and RSV in infants. Requirements: gloves and gown upon room entry, dedicated equipment (stethoscope, blood pressure cuff), and thorough hand hygiene. For C. difficile, use soap and water instead of alcohol-based hand sanitizer because C. difficile forms spores that alcohol cannot kill.

Sterile technique (surgical asepsis) is used for invasive procedures to prevent the introduction of microorganisms into sterile body areas. Key principles: (1) Only sterile items may be used within a sterile field. (2) A sterile barrier that becomes wet, torn, or contaminated is considered unsterile. (3) The edges of a sterile container or package (1-inch border) are considered unsterile. (4) Items below the waist or out of the line of vision are considered contaminated. (5) A sterile field should never be left unattended. When opening a sterile package, open the flap farthest from you first, then the side flaps, and the flap nearest to you last. This prevents reaching over the sterile field. When pouring sterile solutions, pour from a height of 4-6 inches to prevent splashing and contamination. Discard the first small amount of solution (lip of container is not sterile). Sterile gloving technique: open the glove package on a clean, dry surface. Pick up the first glove by the folded cuff (inside surface) using the non-dominant hand. Slide the dominant hand into the glove. Then slide the gloved fingers under the cuff of the second glove and pull it onto the non-dominant hand. If either glove becomes contaminated during application, remove both and start over with new gloves. Common procedures requiring sterile technique include urinary catheter insertion, wound care with deep or surgical wounds, IV insertion, central line dressing changes, tracheostomy care, and surgical procedures. The nurse must maintain the sterile field throughout the procedure and immediately report any break in sterile technique.