All about detergents
Did you know not all contamination on surgical instruments and medical devices responds to cleaning agents the same way?
Surgical instruments and medical devices used during surgical procedures which involves clean, sterile body cavities or tissue. The majority of contamination from these areas are proteins, blood, organic tissue or body fluids. These types of debris are easily cleaned with cleaning agents containing enzymes. The three main enzymes used in cleaning agents for surgical instruments are protease which targets protein, amylase which targets carbohydrates and lipase which targets fats. This is primarily what debris is left on instruments during and after a surgical procedure. This contamination is usually referred to as contamination debris.
The medical devices and surgical instruments used in the gastrointestinal (GI) tract and where areas are lined with mucus membranes have a different type of contamination substances. These substances are primarily made up of bioburden or microorganisms. Depending on where the instrument is used will determine the level of bioburden contamination. The GI tact is one of the dirtiest areas of the human body. It starts at the mouth and continues to the anus. Within that tube there are approximately 100 trillion microorganisms and between 500 to 1,000 different species. The respiratory system has two different levels of microorganisms. The upper respiratory tract – nasal passages, sinuses and oropharynx has the most abundance of microbes such as bacteria and various viruses. The lower portion of the respiratory tract – trachea, bronchi and lungs have fewer organisms due to expelling them through coughing and immune defense mechanisms. Some of these microorganisms are pathogenic or disease producing while the rest are beneficial in keeping us healthy.
Cleaning agents are designed to remove debris and bioburden contamination after a surgical instrument has been used. Getting the instrument clean and ready for the next level of decontamination is the responsibility of the Central Sterile Processing Department. They are the foundation of infection control and patient safety. Knowing how cleaning agents work and how to choose them is a vital part of that responsibility. Understanding why different cleaning agents are used for different types of instrument contamination can be a challenge. This ongoing series of info tidbits can give you additional insight into your daily job.
Did you know cleaning agents have a life expectancy that can be compromised?
Most chemistries come with a designated life expectancy for optimal use. Cleaning agents are no different. We know that shelf life expectancy starts at the date the chemistry is manufactured and put into a container and ends with a predetermined outdate. Use life is from the date the chemistry is opened and put into use. This is usually designated under the instructions for use on the container, meaning it could be 2 weeks or a month. Another cleaning agent life expectancy is how effective it is. Some chemistries such as enzymatic detergents are only effective for as long as the enzymes are present. It is recommended that cleaning agents dosing or solution is done per set of instruments being cleaned. Sometimes you may need to use more than one cleaning solution to get heavily soiled instruments clean.
Storage can play a big role in how cleaning agents maintain their effectiveness. Read the instructions for use or label on the container it gives you conditions under which the chemistry will last the longest and be protected from degradation. The environment should be maintained with a temperature range, humidity level and controlled access. Chemicals can be impacted by heat or cold during transport. Some storage areas may not be climate controlled. When a shipment arrives to be stored it may have a shorter shelf life than you expected. Always check the dates to make sure you will probably use what you have ordered by the time the chemistry outdates.
Enzymes in cleaning agents can degrade for various reasons. Temperature plays an important role in how effective they are as a cleaning agent. If instruments are heavily soiled more cleaning agent is going to be needed. If you live in a really hot or cold climate the enzymes can be less effective. Time on the shelf is one of the most recognized reasons enzymes don’twork as well as they should. If the water is too hot or too cold when the enzymatic detergent is used, it could take longer to complete your work. Make sure to read the label for water temperature range and dosing.
Many manufacturers add additional chemistries to the cleaning agents to help them stay at optimal effectiveness. These can include buffers, surfactants, and chelating agents. Knowing what cleaning agents, you are using and how to protect their effectiveness will help make your job easier.
What is the difference between effectiveness and efficiency when using cleaning agents on surgical instruments and medical devices?
Many times, we hear efficiency and effectiveness used together. Efficiency when using cleaning agents deals with how easily the solution is to prepare, how temperature dependent the chemistry for best results, and how it speeds up or slows down the process. Point of use treatment or removing the residual debris after use helps in two ways. First the majority of the residual debris is removed from the surfaces and internal lumens and second, it tends to keep the instrument set moist – not wet, while the instruments are waiting their turn to be cleaned. Both steps will make precleaning and cleaning much easier in the decontamination process. Researchers have shown that debris can loose up to 65% of the moisture content within 30 minutes. Instruments with dried on debris may require longer pretreatment times before cleaning takes place. Efficiency can be measured in time elements.
Effectiveness on the other hand focuses on how dependable a cleaning agent is at removing debris and bioburden. It also can make the cleaning job easier or take longer. Effectiveness can be measured in several ways. The first and most important is visualization using lighted magnification to determine how clean the instrument is. This involves viewing the instrument while manipulating any moving parts and checking surface and hard to reach areas for residual debris or damage. Instrument testing can be done at this step if it is requiredsuch as testing scissor sharpness or how the clamp jaws fit together. We know that instruments that show damage should be removed from the set and replaced with working instruments. Remember though that visualization is only as good as the person performing the inspection. Not all debris may be visible even with magnification.
Another way of supporting the visualization assessment is to add a second test that measures for specific debris. As we discussed in an earlier post there are different types of contaminants during different types of procedures. There are tests available that measure protein, blood, lumens, adenosine triphosphate (ATP), and dryness of lumens before storage. Each of these tests are fairly easy to use and provide an additional safety net for checking the cleanliness of an instrument or reusable medical device.
Efficiency deals with time saving processes and how smooth workflow occurs when using the product. Effectiveness is how clean the reusable medical device is at the end of the cleaning process. Both of these areas should be considered when you are doing your medical device reprocessing. Understanding why you are certain cleaning agents and testing procedures will help you understand just how important your job is for patient safety.
Can you name three types of damage that can happen to surgical instruments or medical devices if the correct cleaning agent is not used properly?
I asked you to name three but here are more than 3. The first is corrosion. Corrosion can cause rust colored spots, pitting, discolored surfaces, rough or etched areas and corrosion around joints and hinges. Staining and discoloration over time came turn to brown, black or blue. The second one is pitting. This is the appearance of small holes or depressions where debris has degraded the surface of the instrument. Loss of function could be the 3rd problem. Scissors can become dull, hemostats and forceps become stiff, ratchets fail to engage or hold properly and tips of instruments can become misaligned. These are all things that you look for after you have cleaned your reusable medical devices. This where lighted magnification can help you determine if you were able to remove the debris and as you are moving the instruments to visualize hard to reach areas you should be able to feel if they move smoothly or if there is some resistance. Instruments left unattended or cared for after a procedure will end up with some of these problems.
Here is a chart that better shows what can cause damage on instruments if not cleaned and handled correctly and in a timely manner.
| Causes | Damage to an instrument if not cleaned |
|---|---|
| Blood and tissue left on the instrument | Dries and hardens, causing staining, corrosion, and difficulty opening/closing hinged instruments |
| Saline or other chloride-containing fluids | Can cause pitting corrosion, especially if allowed to dry on stainless steel |
| Body fluid and organic debris | Can cause discoloration, corrosion, and buildup in box locks and serrations |
| Improper detergents | May cause corrosion, discoloration, surface damage, or residue |
| Residual detergents | Can leave a film, interfere with sterilization, and contribute to staining/corrosion |
| Hard-water deposits | Leave mineral scale and spots that can damage or obscure the instrument surface |
| Inadequate rinsing | Leaves mineral scale and water spots that can damage of prevent surface contact with the sterilant |
| Instruments left wet | Promotes corrosion, spotting, and mineral deposits |
| Ultrasonic cleaning done incorrectly | Can damage delicate surfaces or finishes if the instrument is not recommended for ultrasonic or the cycle is inappropriate |
| Failure to open hinged instruments | Prevents cleaning solution from reaching the joint and serrations and can lead to debris buildup, stiffness and corrosion |
| Dried-on debris in box locks | Causes stiffness and eventually interfere with the instrument’s movement |
| Poor cleaning of lumens/cannulas | Allows debris and deposits to accumulate internally and interfere with function and sterilization |
| Enzymatic cleaner left on too long or used incorrectly | May contribute to staining or material damage depending on the product and instrument |
| Improper pH cleaning solution | Can contribute to pitting and instrument damage |
| Chlorine/bleach exposure | Can cause significant corrosion and pitting |
| Improper lubrication | Hinges and moving parts can become stiff, increasing wear |
| Overloading cleaning equipment | Can prevent adequate cleaning and cause instruments to strike or rub against one another |
Reusable medical devices today are made from many families of materials. Some may be heat or moisture sensitive. There are instruments that can’t be immersed completely in water or cleaning solution. It is always important to have the manufacturer’s instructions for use for each medical device. The information should include acceptable cleaning agents and methods for getting the medical device clean and ready for the next level of reprocessing. Reusable medical devices are very expensive and sometimes can be hard to replace. Be prepared by knowing your instruments, following IFUs and making sure the instruments are clean and ready for the next step in reprocessing. You are the patient’s best friend, and they don’t even know it. But we do.