14.4 Infection Control & Isolation

Infection Control and Isolation

Quick Answer: Start every encounter with Standard Precautions. Add Transmission-Based Precautions when needed: Contact (gown + gloves), Droplet (surgical mask for close contact), or Airborne (fit-tested N95 + AIIR for TB, measles, varicella). Transmission-Based categories are always in addition to Standard Precautions—never a replacement.

Infection Control Hierarchy for Phlebotomists

Every collection starts with Standard Precautions. When a patient has a known or suspected pathogen whose transmission is not fully interrupted by Standard Precautions alone, the facility adds Transmission-Based Precautions. CDC defines three categories—Contact, Droplet, and Airborne—and some diseases require a combination (for example, pathogens with more than one route).

Isolation is not optional theater. Incorrect PPE choice can infect the collector; incorrect doffing can contaminate hands and clothing; transporting a patient or specimen without following signage can expose elevators, waiting areas, and lab benches.

The Three Transmission-Based Categories

Key distinctions students miss:

• Droplet ≠ Airborne. Droplet uses a surgical mask; Airborne needs a respirator and preferably an AIIR.
• Transmission-Based Precautions are additive to Standard Precautions, never a replacement.
• For diseases with multiple routes, combine categories (facility signage will list the required set).

Reading the Door Before You Knock

Before entering any isolation room for a draw:

1. Read the isolation sign completely—category, required PPE, and any visitor restrictions.
2. Gather all supplies outside so you are not making repeated trips in contaminated PPE.
3. Perform hand hygiene, then don PPE in the correct order before entry (or per posted sequence).
4. Take only what you need; keep the phlebotomy tray outside when policy requires, using a designated clean vs. dirty workflow.
5. After collection, remove PPE carefully, perform hand hygiene, and only then touch clean elevators, charts, or your phone.

If signage is missing or unclear, stop and clarify with the nurse or infection prevention—do not guess.

Donning and Doffing Order

Exact sequences can vary slightly by facility and by which PPE items are required, but CDC teaching examples used in healthcare training follow a consistent logic: put on the most difficult/contaminable items in an order that preserves glove integrity, and remove the most contaminated items first.

Common donning (putting on) sequence when gown, mask/respirator, eye protection, and gloves are all required:

1. Hand hygiene
2. Gown
3. Mask or respirator (N95 for airborne; surgical mask for droplet)
4. Goggles or face shield
5. Gloves last, extending over gown cuffs

Common doffing (taking off) sequence to limit self-contamination:

1. Gloves first (most contaminated)
2. Goggles / face shield (handle by strap/earpieces)
3. Gown
4. Mask / respirator last (for respirators, remove after leaving the AIIR per policy; pull bottom strap then top strap)
5. Hand hygiene immediately after PPE removal

Some protocols remove gown and gloves together; always follow the posted unit sequence. The exam still expects the logic that gloves come off early because hands are the highest self-contamination risk, and face protection / respirator removal is handled carefully by straps only—not by touching the front.

Phlebotomy-Specific Isolation Technique Tips

• Contact precautions: Disinfect reusable tourniquets or use single-patient items; avoid placing your supply tray on the bed; glove/gown before touching the patient or environment.
• Droplet precautions: Don the mask before close contact; if the patient must leave the room, the patient wears a mask if tolerated.
• Airborne precautions: Do not enter without a fit-tested respirator; keep the door closed; minimize time in the room; coordinate with nursing so the patient is ready (ID band visible, arm accessible) before you enter.
• Specimen bags: Place labeled tubes into a biohazard bag using a clean-hand / dirty-hand technique so the outer bag surface remains uncontaminated for lab transport.
• C. difficile note: Contact precautions plus soap-and-water hand hygiene after care is often required because alcohol is less effective against spores—follow facility policy.

Combination Precautions and Specimen Transport

Some infections require more than one Transmission-Based category at once. When signage lists Contact + Droplet or Contact + Airborne, don the full combined PPE set—typically gown and gloves plus the appropriate mask or respirator, and eye protection if splash risk exists. Removing only part of the required set because "I am just doing a quick stick" defeats isolation.

Specimen transport from isolation rooms still follows Standard Precautions plus facility rules: verify labels before leaving the bedside, place tubes in a sealed biohazard bag without contaminating the outer surface, and do not carry used PPE into clean corridors. If a tube must be wiped because of blood on the exterior, clean it with an approved disinfectant before bagging. Never place a contaminated glove or gown into the pneumatic tube or lab courier bin.

Scenario Synthesis

You are sent for a STAT chemistry on a patient with suspected pulmonary tuberculosis. The door shows Airborne Precautions. Correct workflow: verify order and identity plan outside → hand hygiene → don N95 (fit-checked) and any other required PPE → enter the closed AIIR → identify the patient → draw → activate safety device into sharps container → exit → remove PPE in safe order → hand hygiene → transport the sealed specimen. Wearing only a surgical mask for suspected TB is an exam-fail choice.

A second scenario: a pediatric patient with varicella (chickenpox) requires Airborne plus Contact precautions in many facilities because of both airborne spread and lesion contact risk. Read the sign; do not assume one category only because the patient "just has a rash."

High-Yield Traps

• Trap: "Surgical mask is enough for measles or TB." Correction: Those are Airborne—use a respirator and AIIR when available.
• Trap: "Airborne Precautions replace Standard Precautions." Correction: Transmission-Based categories are in addition to Standard Precautions.
• Trap: "Don gloves first, then gown." Correction: Gloves are typically donned last so cuffs seal over the gown; gloves are removed early during doffing.
• Trap: "Droplet precautions require negative-pressure rooms." Correction: Negative-pressure AIIR is an Airborne control; droplet precautions use a surgical mask and spatial separation without special air handling.