What are standard precautions?

Standard precautions are infection control practices applied to every patient encounter, regardless of known or suspected infection. They treat all blood, body fluids (including ocular secretions), non-intact skin, and mucous membranes as potentially infectious. Standard precautions include hand hygiene, appropriate use of PPE (gloves, masks, eye protection), safe handling and disposal of sharps, proper instrument disinfection, and environmental cleaning.

Why must hand hygiene be performed after removing gloves?

Gloves are not perfect barriers -- they may have microscopic pores, tears, or defects that allow contamination. The process of removing gloves (which involves touching the outer gloved surface) can also contaminate the skin. Hand hygiene after glove removal eliminates any residual contamination and prevents transfer of pathogens to the next patient or to other surfaces. Gloves reduce but do not eliminate hand contamination risk.

What disinfection level is required for a tonometer prism?

Tonometer prisms contact the corneal surface (a mucous membrane) and are classified as semi-critical instruments by the Spaulding classification. They require high-level disinfection (HLD) -- killing all vegetative bacteria, mycobacteria, fungi, and most viruses (but not necessarily all bacterial spores). Acceptable methods include 70% isopropyl alcohol wipe with 5-minute air dry, 3% hydrogen peroxide soak, or 1:10 bleach soak with subsequent saline rinse.

When should soap and water be used instead of alcohol-based hand rub?

Soap and water are required when: (1) hands are visibly dirty or contaminated with blood or other body fluids; (2) after contact with Clostridium difficile (bacterial spores that are not inactivated by alcohol); and (3) during adenovirus outbreaks, where handwashing provides better deactivation of adenovirus than alcohol rub. In most routine eye care situations without visible contamination, alcohol-based hand rub is preferred because it is faster, more effective against most pathogens, and causes less skin damage with repeated use.

How should multi-dose eye drop bottles be used to prevent contamination?

To prevent bottle contamination: hold the bottle vertically above the eye without touching the dropper tip to the eyelid, eye, or any surface; gently retract the lower lid and instill one drop into the inferior fornix; release the lid; replace the cap after each use. If the dropper tip contacts any ocular surface, the bottle is contaminated and should not be used for another patient. Single-dose preservative-free unit doses are preferred for patients with active infections or in surgical settings.

Infection Control and Standard Precautions for the CPOA Exam

Standard Precautions in Eye Care

Standard precautions are infection control practices applied to every patient encounter, regardless of whether infection is known or suspected. They are based on the principle that all blood, body fluids (including ocular secretions), non-intact skin, and mucous membranes may contain transmissible pathogens. The CPOA must apply standard precautions consistently and without exception.

Hand Hygiene

Hand hygiene is the single most important infection control practice in any healthcare setting. It reduces transmission of pathogens between patients, from contaminated surfaces to patients, and from patients to staff.

When to Perform Hand Hygiene

Before touching any patient
Before any invasive procedure (instilling drops, tonometry, foreign body removal)
After contact with a patient or their immediate environment
After removing gloves
After contact with body fluids (including ocular secretions)
Before and after handling eye drops (multi-dose bottles can become contaminated)

Methods

Alcohol-based hand rub (ABHR): Preferred for most clinical hand hygiene. Apply 3-5 mL to palms, cover all surfaces, and rub for 20-30 seconds until dry. More effective than soap and water for most pathogens, faster, and less damaging to skin.
Soap and water: Required when hands are visibly soiled or after contact with Clostridium difficile (spores are not killed by alcohol). Wash for at least 20 seconds, covering all surfaces including between fingers and under nails.

💡 Clinical Tip: Adenovirus is one of the few common ocular pathogens that requires soap and water rather than alcohol rub for reliable deactivation. During an EKC (adenoviral conjunctivitis) outbreak, prioritize handwashing over hand rub for staff who have had contact with secretions.

Personal Protective Equipment (PPE)

PPE creates a barrier between the healthcare worker and infectious materials. In eye care settings:

Gloves: Required when contact with ocular secretions, blood, or non-intact skin is anticipated. Change gloves between patients. Do not reuse gloves. Perform hand hygiene after removing gloves (gloves do not replace hand hygiene).
Mask and eye protection: Wear when performing procedures that generate splashes or sprays (irrigation, IOP-lowering injections, surgical procedures). A face shield or goggles protects the CPOA's mucous membranes.
Gown: Worn for procedures with a high risk of splash contamination.

Instrument Disinfection in Eye Care

The CDC Spaulding classification guides disinfection level:

Spaulding Category	Instrument Contact	Required Level	Example
Critical	Sterile body sites (enters eye)	Sterilization	Intraocular surgical instruments
Semi-critical	Non-intact skin or mucous membranes	High-level disinfection (HLD)	Tonometer prisms, contact lenses
Non-critical	Intact skin only	Low-level disinfection	Slit lamp chin rests, trial frames

Tonometer Prism Disinfection

Tonometer prisms contact the cornea (mucous membrane) and are classified as semi-critical. Acceptable methods:

70% isopropyl alcohol wipe with a minimum 5-minute air dry
3% hydrogen peroxide soak, then rinse with sterile saline
1:10 diluted sodium hypochlorite (bleach) soak

Slit Lamp Disinfection

The slit lamp chin rest, forehead rest, and joystick are non-critical surfaces. Wipe with a disinfectant wipe (quaternary ammonium compound or 70% alcohol) between patients.

Drop Bottle Contamination Prevention

Multi-dose eye drop bottles can become contaminated through improper use. The CPOA should:

Never touch the dropper tip to the eye, eyelid, or any surface.
Hold the bottle above the eye (not resting on the lid).
Use single-dose unit dose packaging for high-risk settings (patients with active infection, surgical patients, ICU).
Check expiration dates and discard opened multi-dose bottles per manufacturer or facility policy.

⚠️ Common Mistake: Touching the dropper tip to the patient's eyelid or conjunctiva when instilling drops. This contaminates the bottle with the patient's ocular flora or pathogens. If a bottle tip has touched a patient's eye, it should not be used for another patient and should be discarded or set aside for that patient's exclusive use only.

Key Takeaways

Standard precautions apply to every patient encounter, treating all body fluids as potentially infectious.
Hand hygiene (ABHR or soap and water) is the most important infection control measure -- performed before and after every patient contact.
Gloves protect the CPOA from ocular secretions; hand hygiene must still follow glove removal.
Tonometer prisms are semi-critical instruments requiring high-level disinfection (alcohol wipe + 5-min dry, or soak).
Never touch the dropper tip to the eye or any surface -- this contaminates the bottle.
Adenovirus (EKC) requires handwashing, not just hand rub, for deactivation.