Verification of Washing

Strategies for RMDs

Presented By:

Lon BrusoVice President, SteriTec Products

Verification of Washing

• Quality system basics• Importance of washing verification• Blood residual as a test soil• Verification methods• Verification frequency• Prions

Quality System Basics

• Who did it?• When did they do it?• How did they do it?– Did they follow procedures?

• How effective was it?– Is it verified?

Why is verification of washing so important?

• If it isn’t clean, you can’t sterilize it– Sterilization process specifications are based upon

the assumption that the instruments are clean• What soil is most important to remove?– Blood

• Prions– Washing may be more important than sterilizing

Blood Contamination• Can contain pathogens• Starts as a liquid then coagulates– Flows into hinges and hidden areas– Cleaners must also flow into those areas and

dissolve blood away– Direct impingement and indirect

impingement• What component of blood is most

difficult to remove?– Fibrin

What is fibrin?

• Fibrous protein that is generated as blood clots– Knits a wound together– Generates a water-insoluble covering– White

• Generated by fibrinogen in blood– Fibrinogen polymerizes and forms fibrin as blood clots

Microscopic Fibrin Filaments

Blood Components

• Primarily proteins– Albumin (water soluble)– Hemoglobin (water soluble)– Fibrin (non-water soluble)• Whitish residue• 2-4% in blood

How do you verify?

Challenge the washerTest the items for cleanliness

Challenge the Washer

• Is it functioning properly?– Are the spray arms clogged?– Are the spray arms rotating properly?– Are the spray arms installed properly?

• Is it loaded properly?– Shadows

• Is the detergent working properly?– Temperature– Time– Dosing

Challenge the Washer

• Smear test soil on the item– Check for residuals

• Visibly clean• Inoculate and culture• Protein test

– Still have to clean again before reuse• Adulterated

• Use a pre-made test soil challenge– A washing PCD…Process Challenge Device

Washing PCDs

Wash Checks

Wash Checks H

Wash Checks H

Wash Checks H

Ultrasonic Cleaner PCD

Test the Item for Cleanliness

• Look at it– Visibly clean– Microscopic examination

• Test for residuals– Protein– ATP

• Transient• Expensive

– Need equipment

Protein Test

Protein Test

Frequency of Monitoring

• Traceability to the patient– Each tray?– Each shelf?– Each load?– Once a day?– Once a week?– Once a month?

• Each load is the minimum for traceability to the patient

• What does it cost?

Prions

Alpha Helix

Beta Pleated Sheet

Tissue Particle

Tissue Particle After Heating

A hard shell is created, protecting a core of prions from destruction

After Biological Digestion

When the hard shell is dissolved away through metabolic action, the prions are released

Prions

• Washing may be more important than sterilizing– Sterilizing methods must hydrolyze (cut) the prion

protein chain– Sodium hydroxide methods– Enzymatic methods

• Alpha helix • Beta pleated sheet

What have we learned?

• Cleaning needs to be monitored• Effectiveness of cleaning needs to be verified– Challenge the washer with a washing PCD– Test the items for cleanliness

• Protein test or ATP test

• Frequency of monitoring needs consideration– Each load is minimum for traceability to patient

• Prions are much more difficult to sterilize– Washing might be more important than sterilizing