3.4 Infection Control and Precautions
Key Takeaways
- Standard Precautions apply to EVERY patient and include hand hygiene plus PPE chosen by anticipated exposure (blood/body-fluid, splash, soiling).
- Contact = gown + gloves; Droplet = surgical mask within ~3-6 feet; Airborne = fit-tested N95 (or PAPR) plus an airborne infection isolation room (negative pressure, ≥6-12 air changes/hour).
- Spaulding classification drives reprocessing: noncritical items get low/intermediate disinfection, semicritical (mucous-membrane contact) get high-level disinfection, critical (sterile tissue) get sterilization.
- C. difficile and other spore-formers require SOAP-AND-WATER hand hygiene because alcohol-based rub does not kill spores; aerosol-generating procedures warrant airborne-level protection.
Infection Control on the TMC
Infection-control items are NOT separate from equipment safety — they share the official Troubleshooting and Quality Control of Devices / Infection Control domain, 20 of 140 scored items (~14%). Most stems ask one of two things: what protection is needed before entering the room, or how a respiratory device should be cleaned before reuse. Answer from transmission route and device contact level, not from how sick the patient appears.
Standard Precautions
Standard Precautions apply to all patients regardless of diagnosis. They include hand hygiene before and after contact, gloves for blood/body-fluid contact, and a mask, eye protection, and/or gown when splashes, sprays, or soiling are reasonably anticipated. Because respiratory therapists carry shared equipment between rooms — stethoscopes, pulse-oximeter probes, spacers, masks, transport ventilators, bag-valve-mask devices — cleaning between patients is part of Standard Precautions.
Transmission-Based Precautions
| Precaution | Route | PPE and Room | Respiratory Example |
|---|---|---|---|
| Contact | Touch / contaminated surfaces | Gown + gloves | MRSA wound, VRE, draining secretions |
| Enteric (special) contact | Spore-forming GI organisms | Gown, gloves, SOAP-AND-WATER hygiene | C. difficile after antibiotics |
| Droplet | Large droplets (~within 3-6 ft) | Surgical mask; eye protection per policy | Influenza, pertussis, Neisseria meningitis |
| Airborne | Small particles that stay suspended | Fit-tested N95 or PAPR; negative-pressure AIIR | Tuberculosis, measles, varicella |
| Airborne + Contact | Airborne spread plus lesion contact | N95 + gown + gloves | Disseminated zoster, smallpox |
An airborne infection isolation room (AIIR) is a negative-pressure room with ≥6-12 air changes per hour, exhausted outside or HEPA-filtered, with the door kept closed.
Quick Comparison
| Decision Point | Contact | Droplet | Airborne |
|---|---|---|---|
| Main spread | Hands, surfaces, environment | Coughing/sneezing at close range | Suspended micro-particles |
| Typical mask | Per splash risk | Surgical mask | Fit-tested N95 or higher |
| Room | Private if uncontrolled drainage | Private or cohort per policy | Negative-pressure AIIR |
| Equipment emphasis | Dedicated/disinfected shared tools | Mask patient during transport | Limit aerosol-generating exposure |
| Common exam miss | Forgetting gown AND gloves | Choosing N95 for plain influenza | Using a surgical mask for suspected TB |
Hand Hygiene
Alcohol-based hand rub (ABHR) is appropriate for most routine encounters when hands are not visibly soiled and is faster and more effective than soap for vegetative bacteria. Soap and water is required when hands are visibly dirty and is preferred after caring for C. difficile or other spore-formers, because alcohol does not kill spores — only the mechanical action of washing removes them. Follow the WHO "5 Moments": before touching the patient, before an aseptic task, after body-fluid exposure risk, after touching the patient, and after touching the patient environment. Gloves do NOT replace hand hygiene.
Donning and Doffing Order
- Don: gown, then mask/respirator, then goggles/face shield, then gloves.
- Doff: gloves, then goggles/face shield, then gown, then mask/respirator — performing hand hygiene as you go and removing the respirator LAST, outside the room when airborne precautions apply.
Aerosol-generating procedures (open suctioning, bronchoscopy, nebulized therapy, intubation, manual ventilation) increase exposure risk and warrant respirator-level protection when an airborne pathogen is suspected.
Equipment Reprocessing — the Spaulding Classification
The Spaulding classification ranks devices by infection risk and dictates the minimum processing level:
| Spaulding Class | Tissue Contact | Minimum Processing | Respiratory Examples |
|---|---|---|---|
| Noncritical | Intact skin | Low/intermediate-level disinfection | Stethoscope, BP cuff, ventilator surfaces, reusable O2 mask |
| Semicritical | Mucous membranes / non-intact skin | HIGH-level disinfection (or sterilization) | Flexible bronchoscope, laryngoscope blades, nasopharyngeal airways |
| Critical | Sterile tissue / vascular system | STERILIZATION | Surgical airway instruments, items entering the bloodstream |
| Equipment | Class | Concept | Exam Warning |
|---|---|---|---|
| Stethoscope diaphragm | Noncritical | Disinfect between patients | Don't move room-to-room without cleaning |
| Reusable O2 mask between patients | Noncritical | Facility-approved disinfection before reuse | "Patient-specific" is not "reusable forever" |
| Reusable nebulizer, same patient | Patient-care item | Clean, rinse, dry, store per policy | Standing water grows organisms |
| Flexible bronchoscope | Semicritical | High-level disinfection or sterilization | Leak-test meticulously before reprocessing |
| Surgical airway instrument | Critical | Sterilization | High-level disinfection is NOT enough |
Respiratory Infection Traps
Moist environments breed microbes: do not top off humidifier water (drain and refill), do not leave nebulizer reservoirs wet between treatments, and never drain ventilator condensate toward the patient. Replace filters, suction systems, and disposables per policy and when visibly soiled. Closed (in-line) suction preserves PEEP and limits circuit breaks but still requires aseptic technique; open suctioning of the lower airway requires sterile technique because the catheter enters a normally sterile airway.
TMC Decision Pattern
When the stem names a disease, match the route first (TB → airborne; influenza → droplet; MRSA → contact). When it names equipment, ask what tissue it contacts (mucous membrane → high-level disinfection). When it describes diarrhea after antibiotics, think C. difficile → enteric contact precautions and soap-and-water hand hygiene.
A patient is being evaluated for active pulmonary tuberculosis and needs induced sputum collection. Which precaution set should the therapist use before entering?
After caring for a patient with suspected C. difficile diarrhea, which hand-hygiene choice is preferred once gloves and gown are removed?
A reusable flexible bronchoscope has been used for airway inspection and will be used on another patient. Which processing level matches the device risk under the Spaulding classification?
A respiratory therapist is leaving the room of a patient on Contact Precautions. Which doffing sequence minimizes self-contamination?