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