Review Notes DETAILS
Before instruments can be sterilized, they must be cleaned and decontaminated
Cleaning can be done manually or mechanically.
Manual cleaning is used for delicate or complex instruments and for power instruments like pneumatic, battery or electrical devices that can’t be immersed in a solution
Ultrasonic cleaning is one of the mechanical methods for cleaning instruments before they undergo disinfection or sterilization
Ultrasonic cleaners have proven to be very effective in cleaning surgical instruments particularly those with difficult to reach areas like hinges, joints and box-locks
Ultrasonic cleaning works by transmitting high-frequency sound waves through a chemical solution to dislodge soil from joints, crevices, lumens,ratchets,serrations and hard-to-reach areas which cannot be easily achieved using other methods. The Ultrasonic cleaning uses a phenomenon called CAVITATION
Cavitation is a phenomenon whereby high-frequency sound waves is passed through a cleaning solution to create bubbles, which implode to generate shock waves, strong enough to dislodge impurities adhering to the surface of the objects and lumens submerged in the cleaning solution
The solution used in the ultrasonic cleaner must be low-foaming and have a neutral pH.
Excessive foams will reduce the efficiency of the cleaning process
Recommended temperature of the solution in the ultrasonic tank should not exceed 140 degrees F. This is because high temperature will coagulate protein and make it hard to dislodge.
Before placing instruments in the ultrasonic machine, the solution must be DEGASSED to remove gas or air bubbles in the solution that can interfere with the Cavitation process.
Degassing must be done after each use
The degassing should only be done, after the unit has been filled and not during filling.
The degassing process involves, filling the unit with tap water with a pH around 7 (neural pH) or distilled water, closing the lid and running the process for 5 to 10 minutes.
After the instruments have been mechanically cleaned with the ultrasonic cleaner, the instruments must be rinsed off the solution using DEMINERALIZED water before they can be sterilized
Ultrasonic cleaners can be used to clean aluminum instruments.
Devices with lumen such as robotic and laparoscopic instrument are more effectively cleaned using ultrasonic cleaners
Rubber, plastic, glass, chrome-plated instruments and ebonized instruments should NOT be placed in ultrasonic units.
Ultrasonic cleaning equipment performance should be tested each day it is used and all results should be recorded