Key Takeaways
- Sterile technique is required for procedures that enter sterile body cavities or break the skin
- A 1-inch border around a sterile field is considered contaminated
- If sterility is questioned, the item or field should be considered contaminated
- Sterile items held below waist level or out of sight are considered contaminated
- When opening sterile packages, the flap furthest away is opened first, nearest flap last
Last updated: January 2026
Surgical Asepsis and Sterile Technique
Surgical asepsis (sterile technique) prevents all microorganisms from entering a sterile area. This is essential for procedures that enter sterile body cavities or break the skin.
Medical Asepsis vs. Surgical Asepsis
| Medical Asepsis (Clean) | Surgical Asepsis (Sterile) |
|---|---|
| Reduces number of organisms | Eliminates all organisms |
| Prevents spread of infection | Prevents introduction of organisms |
| Used for most patient care | Used for invasive procedures |
| Examples: hand hygiene, gloves | Examples: surgery, catheterization |
When Sterile Technique Is Required
| Procedure | Rationale |
|---|---|
| Surgical procedures | Enters sterile body cavity |
| Urinary catheterization | Enters sterile urinary tract |
| IV insertion | Breaks skin barrier |
| Wound care (deep wounds) | Exposure of internal tissues |
| Central line care | Access to bloodstream |
| Tracheostomy care | Access to sterile airway |
Principles of Sterile Technique
1. Sterile items touch only sterile items
- Sterile to sterile maintains sterility
- Sterile to unsterile is contamination
2. Sterile field boundaries
- The 1-inch border around a sterile field is considered contaminated
- Only the top surface of a sterile drape is sterile
3. When in doubt, consider it contaminated
- If you're not sure if something is sterile, assume it isn't
- Replace questioned items
4. Sterile items must remain in sight
- Never turn your back on a sterile field
- Keep sterile items above waist level
5. Moisture carries contamination
- Wet items are considered contaminated
- Moisture allows bacteria to wick through
6. Movement around sterile field
- Pass behind another person
- Never reach over a sterile field
- Keep distance to prevent contamination
Setting Up a Sterile Field
Opening a Sterile Package:
- Place package on clean, dry surface at waist level or higher
- Open flap furthest from you first
- Open side flaps next
- Open flap nearest you last
- Don't reach over the sterile field
Adding Items to a Sterile Field:
- Open wrapper as above
- Drop item onto center of field
- Don't touch the sterile contents
- Maintain 1-inch border
Sterile Gloving
Open Gloving Technique:
| Step | Action |
|---|---|
| 1 | Perform hand hygiene, dry completely |
| 2 | Open glove package on clean surface |
| 3 | Pick up first glove by inside cuff |
| 4 | Insert hand, don't touch outside of glove |
| 5 | Pick up second glove with gloved hand, under cuff |
| 6 | Insert hand, adjust both gloves |
Contamination occurs if:
- Bare hand touches outside of glove
- Gloved hand touches bare skin
- Gloves touch non-sterile surface
- Gloves become torn or punctured
Maintaining a Sterile Field
| Maintain Sterility | Breaks Sterility |
|---|---|
| Items at waist level or higher | Items below waist |
| Items in direct view | Items out of sight |
| Dry items and field | Wet or damp items |
| Items opened appropriately | Dropping items onto field |
| 1-inch border avoided | Touching 1-inch border |
When Sterility Is Compromised
If any of these occur, obtain new supplies:
- Item touches unsterile surface
- Field becomes wet
- Item goes out of sight or below waist
- Tear or puncture in sterile barrier
- Unsterile person enters the field
- Any doubt about sterility
Urinary Catheterization (Sterile)
Key sterile technique points:
| Step | Sterile Consideration |
|---|---|
| Prepare supplies | Open on clean surface, maintain 1-inch border |
| Don sterile gloves | Open gloving technique |
| Prepare equipment | Keep supplies on sterile field |
| Clean periurethral area | Use each swab once, front to back |
| Insert catheter | Use dominant sterile hand only |
| Secure catheter | Maintain sterility until secured |
Wound Care (Sterile)
Wound cleaning principles:
- Clean from least contaminated to most contaminated
- Clean wounds: center to periphery
- Infected wounds: periphery to center
- Use each swab for one stroke only
- Dispose after each use
Dressing Change Technique
| Step | Action |
|---|---|
| 1 | Remove old dressing with clean gloves |
| 2 | Assess wound, remove gloves |
| 3 | Perform hand hygiene |
| 4 | Set up sterile field |
| 5 | Don sterile gloves |
| 6 | Clean wound using aseptic technique |
| 7 | Apply new sterile dressing |
On the NCLEX-PN
Expect questions about:
- Principles of sterile technique
- When sterility is compromised
- Correct gloving technique
- Sterile field setup and maintenance
Test Your Knowledge
While setting up a sterile field, the LPN accidentally touches the 1-inch outer border of the sterile drape. What should the LPN do?
A
B
C
D
Test Your Knowledge
During a sterile dressing change, the LPN drops a sterile 4x4 gauze pad onto the floor. What is the correct action?
A
B
C
D
Test Your Knowledge
When opening a sterile package, which flap should be opened first?
A
B
C
D