Sterile Technique

Core Concepts

Principles of sterile technique

These principles are the "rules" that keep a field sterile. Know them cold:

1. Sterile touches sterile only. A sterile item may touch only other sterile items. If a sterile item touches anything non-sterile — a surface, a person, a wet spot of unknown origin — it is contaminated.
2. The edge of the field is contaminated. The outer border (commonly described as about one inch, roughly 2.5 cm, around the drape) cannot be guaranteed sterile, so items are placed well within the field, never near the edge.
3. Keep sterile items above waist level and in view. Anything below the waist or out of your line of sight is considered contaminated — you cannot certify what you cannot see.
4. Never reach across the field. Approach the field with your body and arms clear of it; do not allow anyone else to reach over it.
5. Do not talk, cough, or sneeze over the field. Hair is tied back, masks are worn when policy requires, and artificial nails and uncovered skin lesions are restricted under many facility policies.
6. Keep the field dry. Moisture can wick organisms up through a drape from the surface below, so a soaked field is compromised — replace or re-establish it per policy.
7. When in doubt, throw it out. If you cannot be certain an item is sterile, it is not sterile. Contaminated items are discarded and replaced — never "re-sterilized" at the bedside.
8. Never turn your back on the field. A sterile field is maintained continuously and is not left unattended.
9. Check packaging before opening. Packages must be intact — no tears, punctures, or moisture stains — and within the expiration date; sterilization indicators confirm the contents were processed.
10. Pour sterile solutions without touching. The outside of the bottle is non-sterile; pour into the sterile container without letting the bottle touch it, holding the label in your palm so drips do not obscure it, and follow facility policy on technique details.

Setting up and maintaining a sterile field

Before starting: perform hand hygiene, gather every needed item (once the field is open, fetching supplies means leaving it vulnerable), and check each package for integrity and expiration. Open the outer wrapper away from you, then open the side flaps without reaching across the opened field. Add sterile items without letting anything non-sterile touch them. Once set up, the field must be used promptly and watched continuously; if there is any doubt about it, the safe move is to re-establish it rather than risk a contaminated procedure.

Donning sterile gloves (open method)

The open method is used for bedside procedures that need sterile gloves but no sterile gown:

1. Perform hand hygiene and open the glove package, touching only the outer wrapper with bare hands.
2. Pick up the first glove by the folded cuff, using the thumb and fingers of the opposite (bare) hand — touch only the inside of the glove.
3. Slip the gloved hand in and pull the glove on without touching the outside of the glove with bare skin.
4. With the gloved hand, pick up the second glove by slipping the gloved fingers under the cuff (glove-to-glove contact only), then pull it on.
5. Adjust both gloves, touching only glove surfaces with gloved hands.
6. Keep both hands above waist level and clasped together in front of you — do not let them drop or touch anything.

The rule that makes this work: glove touches glove; skin touches skin. Sterile gloved hands touch only sterile surfaces; bare skin touches only the inside of the gloves.

Sterile technique in common procedures

• Urinary catheter insertion: a sterile kit, sterile gloves, and a sterile field; the catheter must not touch anything non-sterile on its way in.
• IV insertion: the insertion site is prepared with the approved skin antiseptic per facility policy and allowed to dry; the nurse wears clean or sterile gloves per policy and does not touch the prepared site with bare skin.
• Central line dressing changes: typically involve sterile gloves, a mask, and sometimes a sterile gown — maximal barrier practices per facility policy.
• Surgical settings: full sterile gowning, gloving, and draping in the operating room, with the circulating nurse managing the non-sterile side of the boundary.

Exact supplies, glove types, antiseptics, and steps follow facility policy and the manufacturers' instructions. The principles above are what you are held to everywhere.

How It Works: Preparing a Sterile Field for a Dressing Change

1. Prepare the patient and the room: explain the procedure, position the patient, close the door and draw the curtain to limit air movement and distractions.
2. Perform hand hygiene, gather the sterile kit and all supplies, and check package integrity and expiration dates.
3. Open the sterile kit onto a clean, dry surface: open the outer wrapper away from you, then the side flaps, without reaching across the opened field.
4. Open sterile supplies (dressing, saline, and so on) and add them to the field without touching the field with bare hands.
5. Don sterile gloves using the open method — glove touches glove, skin touches skin.
6. Perform the dressing change, keeping hands above waist level and never letting sterile items touch the patient's surroundings.
7. Remove gloves and discard contaminated materials in the appropriate waste container, then perform hand hygiene.

Common Confusions