6.3: Sterile Technique
By the end of this section, you will be able to:
- Describe the different levels of clean and how to achieve each
- Recall common methods of sterilization and disinfection in the healthcare setting
- Demonstrate the different principles of sterile technique
Environmental cleanliness is a foundational concept in nursing. Maintaining a clean environment is essential for preventing infectious disease and the spread of HAIs. In the absence of a properly cleaned environment, the acts of handwashing and donning PPE are substantially less effective in the spread of infection and transfer of pathogens. Nurses must recognize which items in the healthcare environment should be cleaned as well as the proper way this cleaning should be done. They must also be able to identify when an item is contaminated and the proper steps that must be taken for disposal or sterilization. Agency policies, along with governmental guidelines, will help nurses seeking specific answers to these questions.
Levels of Clean
For the chain of infection (see Figure 6.2) to be broken, it is critical that nurses comprehend the proper knowledge and resources for how to clean their environment. To minimize the risk of transmission of infection, there are three levels of cleanliness, in increasing degrees of purity, that specify how specific objects and items should be cleaned: sanitization, disinfection, or sterilization. The concepts of asepsis discussed in 6.2 Asepsis and PPE provides a strong foundation for the three levels of cleanliness.
Sanitization
The removal of visible soil from objects and materials using water with detergents or products that are enzymatically formulated to inhibit microbial growth is called sanitation . Sanitation and cleaning coincide with the goal of medical asepsis, which is to keep all employee and patient-care areas free of debris and contamination. All items must first be cleaned before they can be disinfected or sterilized.
See the competency checklist for Surgical Hand Scrub and Gloving. You can find the checklists on the Student resources tab of your book page on openstax.org.
Disinfection
The process of disinfection removes microorganisms and disease-causing pathogens from inanimate objects. This process is completed on both semicritical and noncritical items. Semicritical items include items that have contact with mucous membranes or nonintact skin. Examples of these types of items include reusable devices, such as endoscopes and respiratory therapy equipment. Noncritical items have contact with skin but not mucous membranes. Because of this, they do not carry a high risk of infection transmission. Examples of these items include stethoscopes, blood pressure cuffs, and bed linens.
Sterilization
The process of sterilization is a procedure that eliminates all microorganisms and spores in or on an object. Critical items require sterilization due to their high risk for infection if they are contaminated. Examples of this include all surgical instruments, catheters, needles, and chest tubes.
A tool that nurses may use in a healthcare setting is an autoclave (Figure 6.9). Autoclaves use high-pressure steam for a designated amount of time to kill pathogens on objects of various shapes and sizes. Common examples are surgical tools, lab instruments, and pharmaceutical objects. Nurses may have various roles in sterilization dependent upon their healthcare setting. Nurses in an outpatient office setting may be responsible for the entire sterilization process, while in contrast, in a surgical setting there may be technicians who complete this process. Nurses must be aware of their specific responsibility in sterilization and develop those skills accordingly.
See the competency checklist for Sanitizing Instruments. You can find the checklists on the Student resources tab of your book page on openstax.org.
Methods of Sterilization and Disinfection
The process of disinfection is carried out by using chemical disinfectants. While some chemicals may have a broad spectrum of effectiveness, those that have a narrower spectrum are typically easier to use and less toxic. Common chemicals used as disinfectants include alcohol, hydrogen peroxide, and chlorine. Sterilization can be done by both physical and chemical methods, or a combination of both.
Physical
The process of physical sterilization within a hospital uses large equipment, such as autoclaving with steam. The steam heats up to 250 to 273°F (121 to 134°C) and inactivates all fungi, bacteria , viruses, and bacterial spores. Steam sterilization is the most common form of physical sterilization used in hospitals. Heat can also be used to sterilize by heating, flaming, incineration, boiling in water, and dry heat.
Chemical
Chemical sterilization uses products, such as ethylene oxide, concentrated bleach, and formaldehyde. This type of sterilization is typically used for instruments, such as those containing rubber, plastic, or glass, that could not tolerate high heat temperatures and/or humidity.
In May 2022, the World Health Organization released a Global Strategy on Infection Prevention and Control to promote the prevention of infections in all healthcare settings.
Principles of Sterile Technique
A sterile technique is the use of practices and procedures that inhibit microorganisms in a specific environment and prevent contamination. This technique is an essential element for patient safety, and it is vital that all nurses understand the principles of the skill. Sterile technique is most commonly practiced in operating rooms and during special procedures, diagnostics, and labor and delivery. It is also used at the bedside for sterile procedures, such as the insertion of chest tubes, central venous lines, and indwelling urinary catheters.
Definition: Quality and Safety Education for Nurses (QSEN) competencies were designed to emphasize key elements that pre-licensure nursing students should be competent in at the time of graduation. Employing evidence-based practice means “integrating best current evidence with clinical expertise and patient/family preferences and values for delivery of optimal health care.”
Sterile technique entails using evidence-based practices and procedures to minimize pathogens and deter contamination in a healthcare environment. Student nurses must know these practices, as recommended by governmental bodies and healthcare-setting policies. Students must demonstrate effective use of sterile technique to reduce risk of harm to self or others.
Clinical scenario: Prior to initiating sterile technique, the nurse must take several critical steps to ensure sterility:
Step 1:
Always perform hand hygiene before initiating any sterile procedure.
Step 2:
Ensure all working surfaces remain clean and dry.
Step 3:
Verify you have all supplies that are needed and that they are within the expiration date.
Step 4:
Keep all supplies in reach to prevent them rubbing against things or dropping.
Step 5:
Bring a second pair of sterile gloves in the event of a break in sterility.
Opening a Sterile Package
Remove any paper or plastic layer that is used to form a barrier between the work surface and inner wrapper. Inspect the package to ensure that it is intact and within the expiration date. To open a sterile package, lay it on a clean and dry surface so that the flaps are facing up, and the top flap is pointed down (forming an upside-down triangle like an envelope). The outside of the package is unsterile as is the 1 in (2.5 cm) border of the package.
Proper technique when preparing a sterile field is critical in order to provide safe care to patients during procedure. Lecturio Nursing has put together a video that describes how to open a sterile kit that reviews this skill.
Applying Sterile Gloves
Clean gloves are different from sterile gloves because with sterile gloves the sterilization process is completed by the manufacturer; they are free from microorganisms and are individually packaged as a pair to remain free of pathogens. Prior to applying sterile gloves, determine your size. The gloves should fit snugly but not tightly. Place the glove package on a clean and dry surface. Using the outside flaps that form the 1 in (2.5 cm) border, open the glove package so that the cuffs are closest to you. Using your nondominant hand, pick up the opposite glove, touching only the inner cuff (the part that will touch skin). Keeping the hand flat and the thumb tucked in, slide your dominant hand into the glove, being careful not to lower hands below the waist (Figure 6.10). Using the gloved hand, slip your fingers into the cuff of the remaining glove. Lift the glove up and away from the table. Slide your nondominant hand into the glove. Keep the gloved thumb up and back to prevent it from touching bare skin. Once both gloves are on, you can adjust to fit fingers as needed. Keep hands above the waist and within the visual field to avoid breaking sterility.
Preparing and Maintaining a Sterile Field
In order to maintain a sterile field, it is critical to follow several protocols. The nurse must always be able to see the field. This means that if you turn your back and can no longer see the field, sterility is broken. Do not reach over the sterile field; even after donning sterile gloves , your arms and sleeves are not sterile. Be aware of any stethoscopes or bandages that may hang into the field, breaking sterility. Any sterile object that is held below the waist is considered nonsterile, including a sterile-gloved hand. Any objects that become wet are no longer considered sterile due to the ability for bacteria to grow rapidly in a wet environment.
Pouring Sterile Solutions
Part of a sterile field may include the use of sterile solution. In order to pour a sterile solution, healthcare providers must follow several steps to avoid breaking sterility. Note first that a solution is sealed and unexpired. Sterile solutions should be poured 6 in (15 cm) away from the field into a sterile bowl or tray from the side of the sterile field, not directly over it. Pour solutions slowly to prevent splashing.
As with all aspects of a sterile field pouring sterile solutions should be done following appropriate technique.