Ultrasonic Irrigation and Cleaning Processes Veronica Day National Clinical Educator In Vitro Technologies Pty Ltd Date: August 2015

Contents Ultrasonic Cleaning Visibility A Better Understanding How do Ultrasonics Clean Degassing Testing

Ultrasonic Cleaning “Ultrasonic cleaners are used to remove soil from joints, crevices, lumens, and other difficult to access locations. The use of enzymatic detergent in the ultrasonic cleaner is recommended. Ultrasonic Cleaners should be monitored routinely to ensure that they are working properly.” The main mechanism of cleaning action is by energy released from the creation and collapse of microscopic cavitation bubbles, which break up and lift off dirt and contaminants from the surface to be cleaned. Frequency's of 37kHZ and above create smaller nodes between the cavitation points which allow for more precise cleaning. The bubbles created can be as hot as 10,000° and 50,000 lbs per square inch, but are so small that cleaning and removal of dirt is the main result.

It’s simple The Rep will sell you the instrument or device and spend many hours showing the CSD staff how to correctly clean it…….but in reality this does not happen. Instrument manufactures should be willing to supply the IFU’s on how to reprocess, dismantle, assemble and sterilise their devices, only they know the intricate complexities of the specific device.

Visibility Test Instrument Fan Retractor Pre cleaning 15sec Water Gun & 45Mins Washer 10Mins Medisafe Ultrasonic

A Better Understanding To get a better understanding... We need to look at the construction of a typical ultrasonic cleaner… Ideally constructed from stainless steel for easy cleaning. Every ultrasonic cleaner has four essential parts!

1. A Powerful Ultrasonic Generator This converts mains electrical power into a high speed electronic signal. Medical device cleaning requires at least 37,000 kHz + vibrations or oscillations per second …(37kHz)...

2. Transducers The transducer (like a loud speaker) converts the electrical energy into sound movement. Or in this case 37kHz + ….

3. A stainless steel cleaning tank The transducers are bonded to a tank which helps with the even distribution of ultrasonic pressure waves in the fluid - water and detergent...

4. Water with a compatible detergent The ultrasonic pressure waves interact with fluid creating “micro cavitation” implosions! Which in turn create a “shock wave” loosening soil/ bio burden

5. Now we have an ultrasonic cleaner.

How do ultrasonic clean The ultrasonic energy enters the liquid within the tank and causes the rapid formation and collapse of minute bubbles: a phenomenon known as cavitation. The bubbles rapidly increase in size until they implode against the surface of the item immersed in the tank in an enormous energy release, which lifts contamination off the surface and innermost recesses of intricately shaped parts.

Remember!!! Water Contains Oxygen (02) Bubbles and other gases …. For ultrasonic cleaning this is not good ! H2O

Degassing Water supplied through water mains under pressure almost always contains dissolved air and other gasses. The cavitation bubbles require gas free liquid to travel through the ultrasonic bath. Dissolved air and other gasses will decrease the effect of the ultrasound wave and the cavitation bubbles. Adding chemistry helps release gas from a liquid. Cleaning chemistry should be added to assist degassing of liquids prior to use.

How long to Degas? Gas bubbles stop rising to the surface of the liquid The liquid no longer has a cloudy appearance There is a rippled pattern on the liquid surface resulting from ultrasonic activity There is a distinctive change in sound. Therefore the length of time required for degassing depends on; *The volume of water *The amount and type of chemistry *The ultrasonic bath

What do ultrasonic waves look like Increased combined field uniformity Decreasing individual transducer intensity

Here is what happen when a transducer stops working. The cold spot

Test the Ultrasonic Bath 1.The function test – can you see and hear the ultrasonic working? 2.Temperature – does the ultrasonic bath indicate the desired temperature? 3.Chemistry - has the correct amount of chemistry been dosed? 4.Time – are we cleaning for the desired amount of time ? 5.Performance test cycle – considering points 1-4 above has the ultrasonic cleaner achieved the desired result? 6.PCDs ……….

Testing for Ultrasonic Energy

Process Challenge Devices

Planning Ahead Just as instruments have become more advanced and complex, so has the sonic cleaning equipment that can be purchased by hospital CSSD. These advances have taken a simple tank with transducers to a level where sonic equipment now can combine the power of irrigation with sonic energy to clean lumen instruments better than ever. Add the advancements that have been made with cleaning solutions and you have a piece of equipment that can:  Improve consistency of cleaning the internal areas of surgical instruments;  Reduce risk to staff from airborne and blood borne pathogens.  Reduce time spent trying to manually clean places that cannot be seen or reached.  Reduce internal and external instrument damage caused by manually brushing, tapping or bending.  Reduce instrument repair budgets.

In Conclusion All automated methods of cleaning have their strengths and weaknesses Ultrasonic cleaning will dramatically reduce the need for pre-soaking and brushing However, pure physics restrict what standard ultrasonic cleaning only can achieve Lumen instrument require air to be replaced with water for ultrasonic activity to occur inside the device … no water, no cleaning Can it/ cant it go through the ultrasonic machine.. Refer to the instrument manufacturer for guidance.. They have an obligation to advise you !!!

Thanks for your attention Questions most welcome……answers not guaranteed!!!!!