What is the difference between sterile technique and clean technique?

Sterile (aseptic) technique aims to eliminate all microorganisms from the surgical field and instruments. It is required for procedures that enter sterile body compartments (the eye, joints, body cavities). Clean technique reduces but does not eliminate microorganisms -- it involves handwashing and gloves but does not maintain a sterile field. Clean technique is appropriate for most non-invasive procedures such as wound dressing changes and routine clinical procedures on intact skin.

What should the CPOA do if they observe a break in sterile technique?

The CPOA must immediately call out the break in sterile technique -- calmly and without blame: 'Excuse me, I think that item may have been contaminated when it touched the drape edge.' The contaminated item must be removed from the sterile field and replaced with a sterile one. Patient safety is the paramount concern, and speaking up about a sterile technique break is a professional and ethical obligation, regardless of the seniority of the person involved.

How does the CPOA open a sterile package without contaminating its contents?

Peel the sterile package wrapper back from the sealed edge, pulling the two sides apart without touching the inner contents. The outer wrapper is not sterile; only the inside is. Present the open package to the scrubbed team member by holding the wrapper edges back and tilting the package toward the sterile field so they can grasp the sterile item directly. Alternatively, flip or drop the contents onto the sterile field without touching the sterile surface.

Why does moisture compromise sterility?

A sterile drape or packaging acts as a barrier to microorganisms. Moisture (water, saline, blood) can penetrate through even intact packaging by capillary action (wicking), carrying microorganisms from the non-sterile outer surface through to the sterile inner surface. A wet sterile package, drape, or gown is therefore no longer considered sterile and must be replaced. This is why the drying phase of the autoclave cycle is as important as the sterilization phase -- instruments must be completely dry inside the packaging before storage or use.

What is a surgical hand scrub and why is it required?

A surgical hand scrub is a standardized procedure that mechanically removes transient (temporary) microorganisms from the skin of the hands and forearms and reduces resident (permanent) skin flora before donning sterile gloves. Even though sterile gloves are worn, punctures or tears can expose the patient to hand flora. The scrub uses antiseptic agents (chlorhexidine or povidone-iodine) applied with a surgical brush for a timed period or using an approved alcohol-based surgical hand rub protocol. It is required before assuming a scrubbed role in any sterile surgical procedure.

Sterile Technique for the CPOA Exam

What Is Sterile Technique?

Sterile technique (also called surgical asepsis) is a set of practices designed to eliminate all microorganisms from the surgical field, instruments, and materials to prevent infection in the patient's wound or open tissues. It is more stringent than standard infection control and is required for any procedure that enters the eye or breaches the skin.

Even though the eye is a mucous membrane environment (not internally sterile), intraocular procedures (cataract surgery, vitreoretinal surgery, intravitreal injections) require the area at and around the wound to be sterile, because any microorganism introduced into the vitreous can cause catastrophic endophthalmitis.

Principles of Sterile Technique

Only sterile items touch the sterile field. Any item that is not definitively sterile is considered contaminated. If there is any doubt -- it is not sterile.
The sterile field is defined and protected. The surgical drape creates a sterile surface. Items that fall below the level of the sterile field are contaminated.
Sterile people and objects touch only sterile objects. A scrubbed surgeon or technician may only contact items within the sterile field.
Unsterile people contact only unsterile objects. The CPOA in a circulating role does not reach into the sterile field.
Movement around the sterile field is controlled. People pass the sterile field at a safe distance or back-to-back, never reaching across.
Moisture compromises sterility. A wet sterile drape or package is considered contaminated because moisture can wick microorganisms through the barrier.

CPOA Role in Maintaining Sterile Technique

Circulating Role (Non-Scrubbed)

The CPOA acting as circulating assistant does not enter the sterile field. Responsibilities include:

Opening sterile supply packages at the edge and presenting them to the scrub technician without reaching inside the sterile field.
Supplying additional items as needed during the procedure.
Handling the sterile drape at the edges to open it, then allowing the scrubbed person to take it from there.
Adjusting lights, operating microscope, or suction -- all non-sterile tasks managed from outside the sterile field.
Monitoring the sterile field for breaks in technique and calling them out (even if it is awkward to do so). Calling a break in sterile technique is not rude -- it is a required safety action.

Scrubbed Role (If Certified)

In some practices, CPOAs with specific surgical training assist from within the sterile field:

Surgical hand scrub before donning sterile gloves and gown.
Maintaining position within the sterile field -- never turning away from the sterile field or lowering the hands below the table level.
Passing instruments to the surgeon without contaminating either party.

💡 Clinical Tip: When opening a sterile package, peel the wrapper back from the seal without touching the sterile contents inside. The outer wrapper is not sterile -- only the contents inside are. Present the package opening toward the sterile field so the scrubbed person can grasp the contents directly.

Surgical Hand Scrub

Before donning sterile gloves and gown for a scrubbed role, the surgical hand scrub removes transient organisms from the skin and reduces resident flora:

Traditional timed scrub: Use a surgical brush and antiseptic scrub solution (chlorhexidine gluconate or povidone-iodine) to scrub all surfaces of both hands and arms up to the elbows for 3-5 minutes.
Alcohol-based surgical hand rub: Apply to clean, dry hands and rub until dry per manufacturer protocol. Approved as an alternative to traditional scrub in many settings.

Donning Sterile Gloves

After the surgical hand scrub, sterile gloves are donned without contaminating the outer surface:

Open method: Used by circulating staff putting on sterile gloves without a scrub gown. Grasp the folded cuff of the first glove with one hand, keeping fingers inside the cuff. Insert the other hand.
Assisted method: A scrubbed person holds the second glove open; the unsterile person inserts their hand while the scrubbed person guides the glove without touching the hand.

⚠️ Common Mistake: Failing to call out a break in sterile technique because it feels awkward to correct a senior person. Patient safety must always take priority. If the CPOA observes any item that might have been contaminated entering the sterile field, they must speak up -- politely but firmly. Silent tolerance of a sterile technique break is never acceptable.

Key Takeaways

Sterile technique eliminates all microorganisms from the surgical field to prevent infection.
Core principle: only sterile items touch the sterile field. When in doubt, it is not sterile.
The CPOA as circulating assistant presents supplies without crossing into the sterile field.
Wet drapes or packages are considered contaminated -- moisture wicks microorganisms through barriers.
Any break in sterile technique must be immediately identified and corrected, regardless of seniority.
Surgical hand scrub or alcohol-based hand rub is required before donning sterile gloves for a scrubbed role.