Chapter 7 Flashcards
What are microbes/microorganisms?
Tiny life forms. Include procaryotes, eukaryotes, and viruses. Some convert matter to simpler forms through decay, some take inorganic compounds and convert them to higher forms.
How much of organic matter do microbes account for on the planet?
60 percent
What is indigenous microflora?
Bacteria, fingi, viruses, and protozoa that live on the skin and inside the human body. Microbes that are harmless under normal circumstances but can become pathogens when they enter the body through a surgical or traumatic wound are called opportunistic pathogens.
What is symbiosis?
The relationship between human hosts and indigenous flora. Refers to both organisms and can be harmful, beneficial, or harmless. Three categories: mutualism, commensalism, and parasitism.
What is mutualism?
Both organisms benefit and depend on each other to a certain extent. Displays synergism where they work together to achieve a result neither could obtain alone. Example is E-coli which produces vitamin K.
What is commensalism?
One organism benefits and the second is unharmed/unaffected.
-Displays neutralism where two organisms occupy the same space w no effect is each other
-Can also display antagonism where one interferes/inhabits the growth or produces waste product toxic to others.
-Example is indigenous microflora on the skin which feed on dead skin.
What is parasitism?
One organism benefits and the host is harmed. Examples include pathogens, SSI, HAI’s, and airborne viruses
What is infection?
Multiplication of organisms in the tissues of a host
What is a nosocomial infection (HAI)?
Infection that is developed in a healthcare setting. Common ones are SSI, pneumonia, GI infection, UTI, and bloodstream infection
Which pathogen is most commonly associated with surgical site infections (SSI)?
-Prokaryotes (bacteria)
-Eukaryotes (protozoa, fungi, parasites
-Viruses
-Prions
Staphylococcus aureus, a gram-positive coccus. Responsible for 30 percent of SSI’s.
Where is Staphylococcus aureus found?
in the flora on the skin, hair, and nares. SSI’s can be caused by both surgical personnel and patient’s own skin.
What are some common bacterial pathogens and what are the infections they are associated with?
Add table later
What is tuberculosis (TB) and what are some precautions which should be taken with known carriers?
Caused by a bacteria called mycobacterium tuberculosis. Usually infects lungs but can infect kidneys, bones, joints, and skins. Elective operations are postponed until drug therapy is effective. Other procedures performed must implement isolation precautions (wearing gloves, eyewear, N-95 mask). Pt must also be informed on how they can prevent cross contamination.
What are viruses and what are some characteristics unique to them?
Nonliving particles that are reliant on the host.
-they are intracellular parasites
-viral replication depends on nucleic acid
-viral cells have RNA/DNA and protein coat that encases nucleic acid
-viral cells depend on protein production of host.
How does the virus enter the host cell?
- viral cell attaches to host with receptors on the capsomeres
- virus enters cell through membrane penetration or receptor mediated endocytosis
- viral replication begins
How do viruses enter the body?
-inhalation of droplets
-through bodily fluids
-ingestion of contaminated food/water
-bites by infected insects
What are some common viral pathogens and what are their methods of transmission?
HBV- body fluids
Hep C- blood
Hep D- body fluids
HIV- body fluids
HSV- fluid from lesions
papillomavirus- contact
cytomegalovirus- body fluids
Creutzfeldt-Jakob Disease (CJD)- unknown but thought to be through CSF. associated w contaminated instruments.
What causes microorganisms to be transmitted on a global basis more easily?
-globalization
-multi-drug-resistant organism (MDR’s)
-some diseases include dengue, ebola, marburg, and lassa
What are prions?
Short for proteinaceous infectious particle. They are nonliving strands of protein that do not have DNA/RNA. Responsible for transmissible spongiform encephalopathy (mad cow, CJD, scrapie)
How does CJD spread throughout the body?
Human body creates protein similar to a prion, called PrP. Responsible for CJD but the normal protein’s structure is different from infectious prion. The PrP changes from a noninfectious alpha-helical form, to the infectious beta-sheet. When a prion contacts normal PrP, it starts a chain reaction in which the prion is replicated by folding the alpha-helical protein into the pathogenic beta-sheet form inside the neurons of the central nervous system (CNS). The beta-sheet prions accumulate in the lysosomes and eventually kill the neuron. The death of the neurons creates holes in the brain tissue, which aids in the release of prions to further invade and infect healthy neurons.
How is CJD transmitted?
Through prion contaminated surgical instruments. Can also be inherited genetically or a sporadic case. Be extra careful of eye tissue, dura mater, brain tissue, and spinal cord.
What are some components of CJD?
-develops very slowly w incubation of 20 yrs
-early symptoms include memory loss and depression
-no vaccine or cure
-diagnosed through EEG or microscopic histology
-variant strand called vCJD or ncCJD has earlier median onset of 28 yrs old. duration of symptoms is longer at 13-14 months.
What are parasites?
Invertebrates that cause disease. Two categories: unicellular and multicellular protozoa.
What are helminths?
Part of the metazoan category. Are commonly known as worms. Primary route of transmission is ingestion of contaminated food and water but also includes penetration through skin, fecal-oral contamination, and arthropod bites. They can migrate outside the intestinal tract and cause issues in other tissues.
What are protozoa?
Unicellular eukaryotes responsible for causing diseases such as malaria and chronic sleeping sickness. Include amoebas, flagellates, ciliates, coccidia, and microsporidia. Transmitted through the fecal-oral route.
What is Entamoeba histolytica?
Protozoa that is responsible for amebic dysentery. Usually in pt’s undergoing a colonoscopy/sigmoidoscopy. Endoscope and other instrumentation should be thoroughly decontaminated.
What is Trichomonas vaginalis. T. vaginalis
A unicellular protozoa that will grow if vaginal/urethral acid levels are off and cause trichomoniasis which is usually and STD.
What are fungi?
eukaryotic organisms that are either unicellular yeasts or multicellular molds and mushrooms. reproduce both sexually and asexually. Majority are opportunistic pathogens that cause infection when host is immunocompromised. Common in HIV/AID’s patients.
What is zygomycosis?
Fungal infection caused by common bread mold. Increase in cases follows organ transplants. One type is the extremely destructive rhinocerebral zygomycosis which causes damage to cranial bones and tissues of the face.
What are the human body’s natural lines of defense?
-structural design of body: skin and mucous membranes
-circulatory and chemical response: immune and inflammatory response
-immunity: active/passive antibody reaction
What does the CDC define Standard Precautions as?
The minimum infection prevention measures that apply to all patient care, regardless of suspected or confirmed infection status of the patient, in any setting where healthcare is delivered.”
What are the standard precautions?
Proper hand hygiene
Use of appropriate personal protective equipment (PPEs)—gloves, masks, gowns, etc.
Respiratory hygiene and cough etiquette.
Safe injection procedures.
Safe handling of potentially contaminated items and surfaces in patient care areas.
What are the modes of transmission?
Direct Contact: Light handle drops into open wound; hypodermic needle-stick injury from two-handed recapping
Indirect Contact: Bioburden on gloves contaminates equipment that is handled by non-gloved person who rubs eyes
Droplet (0.5mm): Infection spread through the air by droplets spread by sneezing, coughing, or talking
Airborne (0.5mm): Infection spread through the air by sneeze droplets
What are the two categories of sources of SSI’s?
exogenous: preop personnel, the environment, and contaminated instrumentation
endogenous: patient’s microflora
How do you prevent infection from the common sources of SSI’s?
Personnel: Don proper OR attire and errors should be noted, communicated, and corrected immediately
Environment: OR’s should be designed with clean zone, filtered/controlled air systems, and soil resistant building materials.
Patient: preoperative antibiotic prophylaxis should be performed. plain or antibacterial drapes may be used. procedures may be postponed until prior infections have cleared.
What are formites?
inanimate objects that may contain infectious microorganisms including walls, floors, cabinets, furniture, and equipment.
What are some factors that increase the risk of developing an SSI?
-age: peds and geriatric pts
-obesity: diminished blood flow, larger wound, difficult adipose
-general health
-carriers of S. aureus and MRSA
-remote infection
-preop hospitalization
-preexisting illness and treatment.
-malnutrition
-tobacco usage
-diabete
-malignancy
What are procedure related factors that increase the risk of SSI?
-preop hair removal: shaving can leave nicks allowing bacteria to colonize
-type of procedure: clean contaminated (class II), contaminated (class III), dirty (class IV), and cases that compromise blood flow carry higher risk of infection.
-duration: longer=higher risk of infection
What is asepsis?
The absence of pathogenic microorganisms or disease
What is the definition of aseptic principles?
Principles applied through use of aseptic (clean) techniques to prevent pathogenic microbial contamination of the surgical environment
What does bactericidal mean?
Substance that kills bacteria
What is bioburden?
The number of microbes or amount of organic debris on an object at any given time; gross contamination on surgical instruments or supplies
What is event-related sterility?
Sterility determined by how a package is handled and stored rather than time elapsed; a package is considered sterile until opened or the integrity of packaging material is violated
What is a fungicide?
Agent that destroys fungal organisms
What is a spore?
A resistant form of bacteria that can form a protective shell and remain dormant to survive in adverse conditions then reproduce when conditions become favorable again
What is a sporicide?
Agent that destroys all bacteria in the spore stage
What does sterile mean?
Having been rendered free of all living microorganisms, including spores on inanimate surfaces.
What is strike-through contamination?
Contamination of a sterile field or package that occurs from the passage of fluid through a microbial barrier
What does surgically clean mean?
Mechanically cleaned and chemically disinfected but not sterile; in surgical scrub procedure, the removal of transient microbes and reduction of indigenous skin microflora to an irreducible level
What is terminal disinfection?
To render items safe to handle by high-level disinfection
What is terminal sterilization?
To render items safe to handle by proper sterilization methods; however, unwrapped so not appropriate for use within the sterile field
What are transient microflora?
Microbes that have been deposited onto the skin surface and are easily removed with routine hand washing
What is a vector?
Living carrier that transmits disease; may show no signs of disease itself
What is a virucide?
Agent that destroys viruses
What is disinfection?
process by which most, but not all, the microorganisms located on inanimate (non-living) surfaces are destroyed. Decontamination is a category of disinfection
What is antisepsis?
process by which most (but not all) microorganisms located on animate (living) surfaces, such as the skin, are destroyed.
What is an antiseptic?
name used to describe the solutions that are used by the sterile surgical team members to perform the surgical scrub and the prep solutions used on the patient for preoperative skin preparation of the surgical site.
How are patient care items classified?
Created by the CDC and FDA: The system rates the degree of risk to patients for infection based on how and where the items will be used
What are critical patient care items?
Items used for invasive procedures or vascular access and carry a high potential for causing SSIs include: surgical instruments, devices that enter the vascular or urinary systems (needles, catheters), implantable items (wires, screws, joint replacements, mesh, sutures), and any monitors or probes that enter deep tissue layers or cavities. These items must be sterilized.
What are semi-critical patient care items?
Items that come into contact with mucous membranes or nonintact skin; however, they carry a lesser risk of infection due to the properties of resistance of intact mucosal linings to many commonly encountered bacterial spores. Examples include: laryngoscopes, anesthesia and respiratory equipment, and some endoscopes. High-level disinfection should be used for items in this category, but sterilization may also be preferred following decontamination.
What are noncritical patient care items?
tems that come into contact with a patient’s intact skin and clean environmental equipment items pose the least risk of infection. Examples include blood pressure cuffs, pulse oximeters, OR transport stretchers, and other furniture. These items require either intermediate-level or low-level disinfection.
What is cleaning?
The physical removal of blood, body fluids, and/or gross debris (bioburden) from an inanimate object.
What are the tree levels of disinfection?
High-level disinfection: Kills all microorganisms except spores and prions (CJD).
Intermediate-level disinfection: Kills most microorganisms, including bacteria, most viruses and fungi, M. tuberculosis and HBV; ineffective against spores.
Low-level disinfection: Kills some fungi and viruses, and most bacteria, but is not effective against spores and M. tuberculosis.
What factors influence the efficiency of disinfectants?
Concentration level of the disinfectant solution. (higher concentration = higher effectiveness but could be too corrosive for some materials)
Bioburden. (exposure to blood, fluids, tissues, etc. decrease efficiency so materials should be cleaned first)
Contact time.
Physical factors of the solution, including temperature of the solution, water hardness, pH level, and exposure time. (solution should come in contact with all surfaces)
What is Glutaraldehyde (Cidex) and what are some components of it?
-high-level disinfectant/sterilant
-for devices that can withstand full immersion
-shelf life is 14 days without surfactant and 28 days with; concentration should be tested before each use.
-prior to immersion, items should be rinsed and cleaned
-after immersion items should rinsed with sterile water
-20 mins in room temp for disinfection, 10 hrs for sterilization
Action: Alkylation of cell protein
Advantages
-dual purpose (both sterilize and disinfect)
-noncorrosive
-effective against positive and negative gram
Disadvantages
-noxious
-unstable (shelf life)
-items have to be dried and cleaned beforehand
Safety
-store in well ventilated room
-wear PPE
-use respirator/mask
What is Sodium hypochlorite (household bleach) and what are some components of it?
-effective disinfectant for floor, surfaces, and equipment
-fast acting and effective
Action: disrupts cellular metabolism
Advantages
-Bactericidal, virucidal, tuberculocidal: it is effective against HIV, HBV, and other viruses.
-Fast-acting solution.
Disadvantages
-Corrosive
-loses effectiveness in organic soil
-noxious odor
Safety
-wear PPE
-don’t mix w formaldehyde
-don’t mix w ammonia
What are some high level disinfectant compounds
-Glutaraldehyde (Cidex)
-Sodium hypochlorite (bleach)
What are some intermediate level disinfectant compounds?
Phenol (Carbolic Acid)
Quaternary Ammonia Compounds
Alcohol
What is Phenol (Carbolic Acid) and what are some components of it?
-disinfects large areas such as floors and countertops
Action: denatures enzymes and causes lysis
Advantages
-economical
-effective in removing feces
Disadvantages
-irritating to skin (isopropyl alcohol neutralizes)
-noxious odor
-irritate resp tract
-for noncritical items
Safety
-wear PPE
-use respirator
-store in well ventilated room
What are the most common HAI’s?
-SSI
-pneumonia
-GI infection
-UTI
-bloodstream infections
What is bacteria?
Prokaryotes that divide by binary fission which are classified based on specific characteristics observed in a lab. Identified by relationship of the microbe to other microbes/humans.
What are some s/s of CJD?
-forgetfulness and memory problems
-confusion and disorientation
-behavior and personality changes
-problems w vision and processing
-hallucinations or delusions
-ataxia
-balance problems
-dystonia
-seizures
-paralysis
-wasting
How is a diagnosis of CJD confirmed?
by examining the brain tissue
What does CJD do to a person?
Attacks the brain. Creates a chain reaction in proteins in the neurons.
What is the primary goal of the SSTR when it comes to infection ?
Vigilant with aseptic and sterile techniques to prevent the perioperative transmission of pathogenic microbes, thereby
preventing SSI’s
What are some principles of disinfection and disinfecting agents?
Safety is important when utilizing.
-have access to MSDS
-use approprate PPE
-well ventilated and temperature controlled storage areas
-follow manufacturer’s reccomendatioins
-do not mix disinfection solutions together
-dispose of expired solutions according to policy
What is Grit Scrub
Physically removing blood, body fluids and gross debris (bioburden) from an inanimate object. Termed doing dishes
Why are there emerging infectious diseases?
Humans are more mobile and viruses adapt to become more resistant. Misuse of drugs can make viruses can do this as well.
What are sterilizing agents?
Agents that destroy all microoganisms including spores but not prions. Could use steam, chemical agents, high velocity electron bombardment, and UV/Gamma radiation.
What are some factors that effect the efficiency of chemical solutions?
-physical factors of the solution (vary in ability to kill microbes)
-selection based on item classification
-manufacturer recommendations (pH, water hardness, temp)
-exposure time: high- 20/30 mins; intermediate/low- 10/15 mins
What are quaternary ammonium compounds and what are some components of it (quatz)
Bactericidal, fungicidal, and pseudomonacidal. Not sporicidal, virucidal, or tuberculocidal. Some facilities consider low quality.
Action: cause leakage of the protoplasm in microbes.
Advantages: Low cost, easy to mix w water, odorless and noncorrosive
Disadvantages: kill limited number of classes of microbes. easily reversed when solution contacts organic debris, tap water, or detergents. Gauze or fabrics absorb the disinfectant ingredient
Safety: wear PPE, store in well ventilated area w controlled temp
What is alcohol and what are some components of it?
a dilution of 60–70% alcohol concentration are tuberculocidal, bactericidal, virucidal, and fungicidal; they are not sporicidal. useful in cleaning and disinfecting small noncritical surfaces. solutions may be as effective or more effective than other compounds for use in skin disinfection for surgical scrub and patient skin prep.
Action: Causes protein denaturation, lysis, and metabolic interruption of cells
Advantages: nontoxic to skin, reduces bacteria on skin, good range of effectiveness against microbes including HIV
Disadvantages: slight odor, highly corrosive, highly flammable
Safety: wear PPE, avoid use in ESU and lasers, prevent pooling, store in well ventilated area
How is the OR designed in terms of decontamination?
-Washable floor and walls
-Easily cleaned furniture
-Effective decontamination and sanitation techniques
-spills/contaminated items should be handled according to standard precautions
-EVS should follow standard precautions and OSHA.
-exposure control plan must be avaliable
What are some guidelines for housekeeping, laundry, and regulated waste procedures?
-should be routine for cleaning and decontamination of OR surfaces, scrub sinks, cabinets, walls, floors, and ceilings
-contaminated work surfaces should be decontaminated by circulator when not possible for concurrent cleaning
-reusable contaminated linens should be uses as little as possible and in leakproof bag. should not be sorted or rinsed in areas of use. wear PPE when handling
-regulated waste should be put into leak-proof that are biohazard with only contaminated items bc it is costly to dispose of
How should the OR be decontaminated prior to the first case of the day?
OR furniture, equipment, surfaces, and lights must be “dampdusted” with a disinfectant solution on a lint-free cloth.
-begin w the highest surface to the lowest to avoid settling of dust
-table should be unlocked and moved to the side to mop floor/clean posts and casters
-mattress pads should be removed to clean both sides, surfaces, and hinges of table
-clean walls if blood and bodily fluid are present
-clean cabinet doors (watch track)
-clean outer surfaces of lights.
How should the OR be decontaminated intraoperatively? (CST Responsibility)
CST may not always be able to perform these procedures if busy. They come secondary.
-Have a basin of sterile water for soaking instruments. Never use NS bc it is corrosive. Wipe instruments w wet sponge
-Instruments w a lumen should be flushed periodically.
-
How should the OR be decontaminated intraoperatively? (RN Responsibility)
-cleaning bioburden from nonsterile surfaces
-changing full suction container. wipe outside and put into biohazard bag. put Isolyser inside
-contaminated surgical instruments from falling should be retrieved and put into basin w water or disinfectant solution or if needed should be taken to substerile room to be sterilized.
-if kick bucket is full, RN/CST can count sponges in 5/10s and place in clear bag for anesthesia. sponges should not be lined up on floor. hanging sponge counting bag systems may also make things easier.
-use something such as sponge stick to transfer contaminated items.
How should the OR be decontaminated between procedures?
Cleaning the OR in between procedures includes removing soiled linens and waste bags, mopping the floor, and cleaning the walls. Referred to as turnover
-suction containers should be disconnected and wiped down then disposed of
-dispose of sharps and put them in puncture proof container
-linen and trash bags should be put into designated area for EVS
-place all instruments into case cart/table w plastic cover for transfer to decontamination room. some ORs have rigid containers for contaminated instruments be careful not to transfer bioburden.
What is the case cart system?
a method for transporting surgical equipment to the OR and back to CSPD.
-at end of procedure CST loads cart w surgical equipment
-cart is transferred to CSPD (could be dumbwaiter or regularly transferred)
-CSPD cleans, decontaminates, assemble, wrap, and store instruments and case cart.
-CSPD uses DPC to pull carts
-Transferred back to OR
What is terminal cleaning?
A thorough cleaning of the room after the last procedure.
-ceilings, floors, and lights are wiped down
-all furniture is wiped down
-OR table is thoroughly wiped down
-all equipment is wiped down
-horizontal surfaces are cleaned
-equipment is moved to the side and OR floor is thoroughly flooded w disinfectant and wet vacuumed
-equipment is moved back.
-substerile room, stretcher, scrub sinks, and OR halls (wet vacuumed) are also cleaned
Particular attention should be paid to scrub solution dispensers.
What is weekly cleaning in the OR?
Cleaning and disinfection processes are scheduled on a weekly basis.
-ceilings and walls are thoroughly cleaned inside and outside including halls.
-mounted light fixtures are cleaned
-air vents and heating duct grills are vacuumed
-inside/outside of supply cabinets are cleaned
-sterile supply rooms and storage areas are cleaned
-housekeeping supply rooms are cleaned
What are dirty cases and how are they treated differently?
Cases where there is known infection. -should be the last scheduled case of the day
-floor, ceilings, and walls should be cleaned w phenolic detergent
-furniture is cleaned w a 70% alcohol solution
-rubber/plastic tubing is replaced
What are some components of the decontamination room?
-Filtered air is exhausted to the outside of the health care facility.
-The minimum air exchange rate is 10 times per hour and negative pressure maintained.
-Temperature should be maintained between and with a humidity of 35 percent to 72 percent.
-when design CSPD of does not allow the separation of decontamination and clean work areas to prevent cross contamination. Personnel should wear PPE.
What is the first step of the decontamination process and what are CST’s responsibilities?
First step is cleaning.
-presoak contaminated instruments. (use sterile water, proteolytic enzymatic and lipolytic enzymatic solution, and then detergent solutions)
-confine instruments in closed containers
What are the advantages and limitations of pre soaking solutions?
Sterile Water: keeps organic debris moist but ineffective in softening or removing dried debris
Enzyme solutions: Removes moistened and dried debris w/o mechanical action but efficiency depends on concentration, temp, and contact time.
Detergent: Keeps organic debris moist while loosening dried debris but mechanical action is still required to remove soil.
How should the CST load the case cart?
-Place heavy instruments on the bottom of the tray and not on top of other delicate instruments
-Instruments w ring handles should be unratcheted and stringed instruments should be facing the same way
-Instruments w multiple parts should be dissembled
-Enzymatic foam spray may be sprayed over instruments
-Transport case cart to decontamination.
What is the purpose of cleaning?
physically remove debris that was not removed or softened during the presoak. disinfectant agents are weakened in the presence of organic soil.
What methods are used when cleaning instruments?
Chelation: binding minerals in the solution. prevents deposit on the surface of surgical instruments, which causes spotting.
Enzymatic: Catalysts that aid in breaking down organic soil into solution.
Emulsification: The action of dispersing two liquids not capable of being mixed.
Solubilization: solubility of a substance is increased within a solution.
What are some common types of chemical cleaners?
Enzymatic: aids in chemical reaction of breaking down organic debris. specific to the type of debris to be removed. require dilution and more effective in warm water.
Ultrasonic: manufactured specifically for ultrasound cleaners. may have surfactant and chelating agents
Manual Detergent: used for hand cleaning or pre soak. high foaming should not be used in mechanical cleaning equipment. instrument must be rinsed thoroughly
Washer-decontaminator: liquid solution w thee pH levels. Neutral pH: least corrosive but lease effective. Moderate pH: low-level alkaline, may be combined w surfactant and chelating agents, safe for stainless steel but may be harmful for chromium oxide layer. High pH: Most effective but corrosive, should be used w neutralizer.
What are the steps for surgical instrument decontamination?
-Clean
-Disinfect (renders safe to handle)
-Inspect (includes lubricate and sort)
-Package
-Sterilize
-Store
What is the 3-sink method used in cleaning instruments?
First sink- Instruments are washed in lukewarm water, enzymatic cleaner (neurtal pH), detergent, and solution filled water
Second sink- Intermediate rinse w distilled water
Third sink- Final distilled water rinse to prevent spotting
What should the tech ensure when preparing instruments to go through mechanical cleaning equipment?
-Instruments placed into a perforated/wire mesh tray to prevent interference with the cleaning action of the machine.
-Heavier instruments placed on the bottom of the tray
-Hinged instruments must be left in an open position
-Instruments with attachments must be disassembled.
-Instruments with concave surfaces should be placed upside down
What is mechanical cleaning equipment and why was it made?
Machines that eliminate manual cleaning to protect personnel. Includes washer-sterilizer, washer-decontaminator, and ultrasonic cleaner
What is the cycle of the washer-decontaminator?
Pre-rinse: some use enzymatic solutions
Cleansing: Detergent solution
Final rinse: 180-195 degree water
Dry: uses high temp
Some have ultrasonic cleaning phase. Allow hands off processing but no sterilizing. Instruments are safe to handle bc considered immediate level disinfection
What is the washer-sterilizer adn what are some components of it?
-can process majority of stainless steel and heat resistant instruments
-bioburden should be removed to prevent baking on
-stainless steel items should not be put next to other materials bc an electrolytic reaction can occur and fuse them together
-uses a free-rinsing, low-sudsing w neutral detergent. high sudsing will leave residue
-instruments are deemed safe to handle, high level disinfected, but not ready for use in surgery.
-two types. tunnel like chamber w door at each ends and rotating sprayer arms. also have a horizontal/cabinet type which has a door on one end.
What is the cycle of a washer-sterilizer?
-Pre-rinse: A cool/lukewarm water spray rinse removes soil.
-Automatic detergent injection
-Fill phase: The chamber is filled with water
-Wash phase: Water is agitated inside the chamber for soil removal; the machine controls water temperature.(270 degrees)
-Post-rinse: Loose soil and detergent film are rinsed off items.
-Sterilization phase: Steam sterilization cycle—this is usually a gravity cycle.
-Lubrication (milking)
-Drying phase
What is the ultrasonic cleaner and how does it work?
Removes small organic particles from areas of instrumentation that manual and mechanical cleaning cannot get to by use of cavitation.
Uses high frequency sound waves converted to vibrations. The energy sets molecules in rapid motion forming microscopic bubbles on surface of instrument. Bubbles enlarge, become unstable and implode- creating a vacuum. Particles are dislodged and float to the surface of the solution
What are some factors to remember with the ultrasonic cleaner?
-Instruments are placed into a mesh tray for exposure. (emersed in a warm water, low-sudsing, neutral pH solution
-Machine must be de-gassed (running empty cycle)
-Fluid must be frequently changed bc of buildup of bioburden.
-Lid should be kept closed when running the cleaner bc there are fine particles that can be harmful
How should instruments w lumens be cleaned?
Should be flushed until liquid is clear. Hydrogen peroxide is a great irrigation solution but must be rinsed away.
How should power instruments be cleaned?
Should NEVER be submerged.
1. leave air hose attached
2. wash cord w lukewarm water, neutral detergent, and a cloth/soft-bristled brush
3. wipe handle w ^
4. rinse all components w distilled water
5. may need to be oiled
How should rigid endoscopes be cleaned?
- Channels, holes, and joints should be thoroughly cleaned
- soak endoscope in enzymatic solution
- use hand-held washing gun for washing and compressed air for drying
- use detergent from manufacturer
- take care w eye pieces and lenses
- avoid denting to keep light fibers safe
How should flexible endoscopes be cleaned?
- long flexible cleaning brushes are used to clean channels
- soak in enzymatic solution w ports open. flush w cleaning solution
- exterior should be cleaned w neutral solution and soft brush/cloth
What is instrument lubrication (milking)?
Lubricated to maintain optimal function. Should be sprayed or immersed. Fully effective after sterilization. Left on during assembly, wrapping, and sterilization.
What are some standards of packaging material?
Used to enclose a device that is to be sterilized and maintains sterility.
- maintains the sterility of the items until use.
- permit the package to be opened in a manner that allows for easy removal of the sterile items without contamination
- allow the sterilizing agent to penetrate and reach all surface areas of the items to be sterilized.
What are some characteristics of packaging material?
-Efficiency: conform to size/shape, cover contents entirely, flexible and memory free
-Ease of opening
-Sterilization suitability: allow air to be removed, withstand conditions from autoclave, allow for escape of sterilizing agent, allow contents to dry
-Strength: resist tears and punctures, avoid degrading
-Barrier efficiency and support impermeability
- Seal integrity
- Safety
-Sterility maintenance
What are some components of woven textiles?
-Made of cotton and cotton blends
-Reusable so must be laundered. W repeated laundering fibers may be lost and sheet must be discarded.
-must be inspected for holes
-can be treated to be moisture resistant
-comes in single and double ply (a towel may be placed in between instrument and wrap to assist w moisture absorption)
-ranges from 140-288 thread count
What are the advantages and disadvantages of woven textiles?
Advantages: Economical and reusable. Easily penetrated by sterilant.
Disadvantages: May absorb moisture during steam sterilization, least effective at providing bacterial barrier, not recommended for use w EtO, require laundering
What are some components of non-woven textiles?
-Disposable
-Made of various shapes and sizes
-Made of plastic synthetic fibers
-Laid out flat when stored
What are some advantages and disadvantages of non-woven textiles?
Advantages: Excellent barrier, lint free, impervious to moisture, tear resistant
Disadvantages: Cost, not as “memory-free”
What are some components of paper wrapping?
-Single Use, Disposable
-Easy memory but not as flexible
-Easily penetrated by steam
What are some advantages and disadvantages of paper wrapping?
Advantages: plentiful supply, inexpensive, porous
Disadvantages: Brittle in dry conditions, easily torn, not unifrom in thickness
What are some components of Tyvek Plastic (Pouch Packaging)?
Used w EtO and Sterrad. Steam can damage the contents.
What are some components of plastic paper pouch packaging?
-Used w steam and EtO.
-Most common in hospital.
-Plastic must be about 2mm, allow for visualization.
-One side of pouch is paper, one is plastic
-The side and top edges are heat sealed w an open end for item to be placed. Open end is then heat sealed, taped, or strip of adhesive which is folded over.
-Available in precut sizes or in roll which is cut to size
-Do not use staples or rubber bands to close
-Place items so the end of the item can be grabbed by CST
-Correct size is important. Too big can compromise sterility. Too small can tear and be difficult to remove air.
-If writing on pack, write on plastic
-As much air should be removed as possible
-Sharp edges should be protected w tip protectors
-Heavy items w multiple parts can be double peel packed
-
What are some characteristics of rigid instrument containers?
-Reusable
-Provide assurance of package integrity bc can’t be torn
-Easily opened
-Uses a chemical indicator to ensure sterility
-Used to return contaminated items
-Come in a variety of sizes, designs and are stackable
What are some sterilization recommendations for rigid instrument pans?
-Can be safely sterilized w other supplies. Should be placed beneath absorbable items to prevent condensation drips.
-Drying time should be increased to allow revaporization of condensation
-Use prevac instead of gravity for adequate air removal
-Check gaskets
-Disposable filters should be replaced after every use
What are some general principles of packaging?
-max size for Muslin wrap is 12x12x20 and item should not exceed 12 lbs
-linen packs should be loosely packed
-double wrapping is essential (double ply)
-should be inspected for holes
-chemical indicator tape is labeled
-size matters. too big can inhibit penetration. too small can tear at corners and cannot cover. if used to establish field, wrapper must extend 6 inches below. must cover hand if being thrown
-Place towel between bottom of tray and wrap to cushion corners
-Don’t pack set too dense. ANSI and AAMI says don’t exceed 25 lbs
-Dust covers should be 2-3mm thick and labeled
What are the steps for preparing instrument and basin sets?
Inspection, Reassembly, and Preparation
What are some key factors to remember for inspection?
-Inspect for bioburden
-Scissors should have no burs or cracks. Blades close smoothly. Sharp enough to cut two 4 × 4 sponges with little effort.
-Ratchet must lock properly
-Jaws of clamps close evenly
-Forceps close evenly with tips evenly lined.
-Ratchets on self-retaining retractors remain locked in the open position and release with little effort.
-Points on nondisposable trocars should be inspected for burs, cracks, scratches, or bends.
-Manufacturer’s instructions must be followed for proper inspection of powered instruments. May need to be lubricated. Power hose should be checked for cracks and cuts. The power hose should be coiled loosely to prevent kinking and damage.
What are some key factors to remember for reassembly?
Some instruments might need to be reassembled. Some should not to make sure steam reaches all surfaces (Balfour, poole suction tip, staplers).
What are some things to ensure during preparation?
-Sterilant comes into contact with all surface areas.
-Positioned in a protective manner
-Evenly distributed
What are some regulations to remember for preparation?
-Instruments placed in a mesh-bottom w towel lining the bottom to allow penetration of sterilant
-Instruments should be evenly distributed w like size, shape, and function, grouped together
-Special trays for micro-instruments
-Small residual of distilled water should be left in lumens
-Concave instruments placed on their sides
-Loose instruments should not tightly group or piled
-Large, loose instruments should be placed so there is minimal movement w heavier ones on bottom and towels can be used to separate layers
-Absorbent towel should be placed between basins and items in basin. No sponges and woven materials in basin. OR handles be placed down. Basin should be placed w fold down. Should be no more than 7 lbs.
-Trays should contain all instruments for a procedure. Also be autoclaved flat.
What are the two different types of folding used during preparation?
Envelope- small trays and individualized items
Square (Parallel)- large packs and instrument trays
Why should items always be labeled?
-Content
-Inventory control
-Rotation of stock
-Quality assurance
What should label information include?
-Name of tray or package contents
-Date of sterilization
-Identification of the sterilizer used (usually by number designation)
-Cycle or load number
-Initials of the employee who prepared and processed the package
-Department to which the package belongs
What is used to label?
Permanent marker, labeling gun, bar code scanning labels
What type of date is used when labeling a package?
Julian date. It’s the number of calendar days but no year
What are the different methods used for sterilization?
Steam, Chemical Agents, High-electricity bombardment, UV/Gamma radiation
What items can be steam, gas, and chemically sterilized?
Thermal (steam, dry heat): Most metal surgical instruments, powered instruments, micro-instruments
Gas (EtO, Gas plasma): Powered instruments, Delicate instruments, Fiberoptic instruments, Lensed instruments, Plastic, Rubber, Porous and MOISTURE and HEAT sensitive items
Chemical (Cidex, Steris): Lensed instruments, fiberoptic instruments/cables, heat-sensitive instruments
What are some advantages and disadvantages of steam sterilization?
Advantages: more effective in transferring thermal energy, protective outer layer of microorganisms is softened allowing denaturation, most economical, safest, quick, nontoxic, easy to maintain quality control, readily available
Disadvantages: Human error, heat and moisture sensitive items cannot be sterilized w steam
What are the factors that are critical to steam sterilization
-Temperature
-Moisture
-Air
-Pressure
-Contact
-Time
Time
The minimum time for sterilization will depend on temperature and cycle type. (gravity displacement and dynamic air removal). Some microbes are harder to kill than others
What are the minimum cycle times for a gravity displacement cycle?
Wrapped set: 250deg- 30mins; 270deg- 15 mins; drying time-15-30 min
Unwrapped set (no lumens): 270deg-3mins; drying time- 0-1 mins
Unwrapped set (lumens): 270deg- 10mins; drying time: 0-1mins
What are some common errors that affect contact and what can be done to fix them?
-Strainer is obstructed. Make sure it is lint fee
-Containers are placed incorrectly. Should be positioned to allow escape of steam and circulation. Items are packed and wrapped loosely.
What are the minimum cycle times for dynamic air removal steam sterilization?
Wrapped set: 270 for 4 mins; dry 20-30 mins
Unwrapped set (no lumens): 270 for 3 mins
Unwrapped set (lumens): 4 minutes
Temperature
Should be at a good temp to kill spores.
Pressure
Raises the temperature of steam to force it into packaging
Moisture
-Should be 97-100% humidity
-Acts as a catalyst to temperature to coagulate and denature proteins as it allows for a lower temperature (6 hours dry = 12 minutes wet)
-Cold metal on moist heat can create condensation
-97% heat w 3% water. Less than 3 is too dry and won’t penetrate. More than 3 is too wet and packs will be soaked which causes strike through contamination
Air
Should be completely removed. Air doesn’t mix w steam so it sinks to the bottom of autoclave and should be removed via gravity displacement or prevac.
What are the basic components of an autoclave?
-Ranges from large to small
-Metal Jacket:
How does a gravity displacement sterilizer work?
Relies on gravity to remove air from chamber. Steam enters at top so air sinks and is drained. Slower than a prevac sterilizer. Pack loosely so air doesn’t get trapped.
Cycle-
Conditioning: steam enters chamber, air is displaced, temp and pressure are reached
Exposure: Temp is maintained for required time
Exhaust: Steam valve closes, drain opens, steam is removed, filtered air is let in and pressure becomes normal
Drying: Heated, fresh air vaporize and packs are dried.
How does a dynamic air removal autoclave work? (Prevac)
Uses a vacuum pump to remove air making cycle faster.
Cycle-
Air removal (prevacuum): Vacuum pump removes 90% of air
Conditioning: Steam injected into chamber.
Second air removal phase: Vacuum removes remaining air (99% is gone atp)
Exposure: Steam enters chamber and temp is held
Exhaust: Outlet opens and steam is drained
Drying: pump turns on and produces 90% vacuum to remove moisture. Filtered air and normal pressure is returned.
What is a flush-pressure-pulse cycle?
Another version or dynamic air removal cycle but has 4-5 vacuum phases. Steam enters in between each of the vacuum phases to aid in removing air and preconditions load by penetrating packages. Eliminates the need for a Bowie Dick Test.
What are the advantages of a dynamic air removal autoclave?
- Increases speed of operation
- More efficient at removing air
- Not as dependent on the positioning of load
- Condensate is produced during preconditioning phases, reducing cycle time
What is the Bowie Dick Test?
Test which checks for air removal in prevac autoclaves.
-performed at first run of day and after repairs
-placed on front bottom shelf over drain
-test is charted
-commercial test is called DART and stands for daily air removal test
-does not test for sterilization
-look for a uniform change in color.
What is immediate use steam sterilization? (Flash sterilization)
Sterilizing dropped items.
-Most common method CST’s use.
-Avoid as much as possible especially implantable items.
-Decontaminate item first and place in perforated tray
What are some general safety precautions to take when flash sterilizing?
-Chamber walls are hot and can burn
-Make sure door is closed tightly before starting
-Only open door when exhaust valve says pressure is 0
-Stand behind door to avoid steam
-Don’t touch item until cool. Towels can be used as hot pads
Why is sterilization monitored and what are the methods of monitoring?
Monitored for quality assurance, ensurance of sterility, and proper operation of sterilizer. Methods are mechanical, chemical, biological, and administrative.
Mechanical Monitoring
Autoclaves have gauges and recorders to monitor progress of sterilizer. Traces over a 24hr period. Prints record and is charted which can be used legally. Print should be verified and initialed it verifies sterilizer worked properly.
What is chemical monitoring?
Used internally and externally to ensure that items have been exposed to proper temperature, humidity, and sterilant. Detects sterilization errors which can be caused from machine malfunction, incorrect assembly or wrapping, and incorrect loading.
How are chemical indicators classified?
Class 1: Process indicators—indication of exposure to the sterilizing agent.
Class 2: Indicators for use in specific tests—assessment of a specific function of the steam sterilizer (e.g., Bowie-Dick test).
Class 3: Single-variable indicators—determine if a single parameter is being met, such as temperature.
Class 4: Multivariable indicators—designed to react to two or more of the parameters
Class 5: Integrating indicators—designed to react to all sterilization parameters. Most accurate indicators. Can be used to release loads that do not include implants. An example is a challenge test pack.
Class 6: Emulating indicators—designed to react to all sterilization parameters of a specific sterilization cycle.
What are some components of chemical indicators?
-Paper impregnated w dye that changes in presence in temperature and sterilant
-Autoclave tape has diagonal lines that are creme or green and turn black
-Internal steam indicators are placed in the hardest part for sterilant to reach. Read when package is opened.
-Rigid containers may have dots that become black
-Peel packs may have a dot or edge
-Chemical indicates exposure
What is biological monitoring?
Device that contains certain microorganism which is killed when exposed to sterilant. Microbe is in spore stage. Guarantees that items are sterile and conditions have been met.
What is the biological indicator for steam sterilization
Geobacillus stearothermophilus. Highly resistant to steam but harmless to humans.
What are some components of biological indicators?
-Comes in packs which can be commercially or house made according to AAMI standards but is difficult.
-Placed in hardest part for sterilant to reach which is bottom front over drain chamber.
-At end of cycle, the vial is crushed. If yellow it means it failed. If red it means it passed.
What are some considerations for incubating biological indicators?
-Incubated for 24hrs.
-Incubated at 131-140 degrees.
-A control/test vial is used to validate the results
-Frequency of testing ranges from weekly to daily (busy facility)
-Always monitor for implantable items
How can steam sterilization be troubleshot?
-Wet packs should be considered contaminated bc of wicking. Moisture from packs results from too many instruments in tray, sets are assembled w/o towels, woven packs are wrapped too tight, trays are improperly loaded.
-Sterilizer (esp pipes) should be examined yearly
-Filters w brown or orange spots indicate steam is not pure
What is Ethylene Oxide (EtO) and what are some components of it?
Used to process materials like plastic, rubber, and MRI safe plastic.
-Kills all microorganisms + spores
-Noncorrosive
-Gas comes in cylinders which withdraws air from chamber and replaces it w EtO
-Temp increases permeability of cells but not as high as steam (85 to 145)
-Humidity should be kept between 30 and 80%
-Instruments should be free of lubricant bc EtO cannot permeate and if mixes w water becomes ethylene glycol which is toxic.
What are some disadvantages of EtO?
-Very expensive
-Toxic (can lead to skin/respiratory irritation, headaches, nausea, cancer, reproductive issues, and chromosomal alterations)
-Flammable (contains chlorofluorocarbons to reduce but bad for ozone)
-Long sterilization process since packages have to be aerated which lead to long turnover
-BI is basilis atropheas (should be ran w every load)
What are some components of the EtO sterilizer?
Sterilization machine w separate vented chamber. There are vacuum pumps to remove air and humidifiers to maintain humidity. Favorable setup is sterilizer and aerator but if not available aerate in chamber for 8hrs at 140 or 12hrs at 120
What are some advantages and disadvantages of gas sterilization?
Advantages: can be used to sterilize materials sensitive to heat and moisture, less corrosive, less damaging
Disadvantages: Aeration times are lengthy, personnel hazards, and damaging to certain materials
What are some components of Hydrogen Peroxide Gas Plasma (sterrad) and what are some components of it?
Uses gas at lower temp to sterilize heat and moisture. Electrical current is passed through hydrogen peroxide gas creating a cloud of plasma which penetrates materials and creates free radicals inactivating microbial life.
-Bi is Bacillus atrophaeus. CI is tape that turns pink.
-Cannot be used for lumens bc diffuser has not been approved by FDA
-Can be used on nonwoven materials and tyvek (no paper)
-Chambers should be loaded w adequate space. Multiple cartridges are loaded into sterilizer. Cycle ranges from 28-38 mins and does not require aeration.
-Paper is printed demonstrating cycle parameters
What is liquid chemical sterilant used for?
For instruments that are heat sensitive but moisture stable. Include Glutaraldehyde and Peracetic acid (Steris)
What is Steris and what are some components of it?
Uses peracetic acid. It is a strong sterilant and should be carefully handled.
-Cycle takes 23 mins at 122 degrees
-Sterilizes flexible and rigid scopes
-BI is Geobacillus Stearothermophilus or there are chemical strips that measure concentration but are not at valid
-expensive
-for immediate use only bc sterilized w cassete
What is the sterilization cycle for Steris?
1–2 minutes: Water enters the processor through a three-step treatment process.
2–4 minutes: Treated water mixes with a peracetic acid germicide, creating a solution to process the items.
4–10 minutes: Six-minute exposure phase destroys all microbial life on items.
10–12 minutes: Solution rinses safely down the drain.
12–18 minutes: Two rinse phases remove chemical residue.
18–23 minutes: Automated filter integrity test confirms that the filter operated successfully.
23rd minute: Validated items are ready for immediate use.
What are some factors of ionizing radiation sterilization?
-Commercially used
-Uses irradiation to produce chemical and thermal energy which disrupts DNA and kills microbes/spores
-Use radioactive gamma rays or beta particles.
-Package integrity is used to monitor sterilization.
What is ozone gas sterilization?
Alternative method of sterilization which oxidizes bacteria.
-Destructive to plastics and metal and corrosive to some metals. Cannot be used on long cannulated instruments
-Generator converts oxygen to ozone and it penetrates cell membranes causing them to explode
-Machine uses vacuum pump to increase penetration
-Cycle is 60 minutes w no aeration needed
What is Vaporized Hydrogen Peroxide (VHP)?
-Uses hydrogen peroxide in gas form to sterilize
-Cannot be used on paper wraps, nylon, rubber, and some metals.
-Has not been cleared by FDA for use in facilities
What are the administrative controls of sterilization?
Documentation is key. All mechanical printouts and preventative maintenance, items, patient, team member, and results of indicator must be charted. Used in court of law, to track infection, and inspection by the Joint Commission.
What is event related sterility?
Contamination is event related instead of time related. Package will remain sterile unless torn, wet, etc. It is more economical. Depends on quality of wrap, storage, transport, and handling.
What is surgical conscience?
CST must have a understanding of
asepsis and sterile technique and adhere to and permit no compromises in the entire perioperative period. Involves constant inspection, monitoring and
regulation of the patient, sterile field, environment, personnel and equipment. The CST anticipates the needs of the patient, the surgical team, and gives unselfish, vigilant care.
What are the AST standards for establishing the sterile field?
