Cleaning, Sterilization, Disinfection, Asepsis

Question 1

Which of the following is likely to result in the highest efficacy of medical instrument cleaning: a. Use of a central reprocessing area for all instrument cleaning b. Local instrument reprocessing within the area of care c. Use of an acidic pH cleaner d. Allowing the instrument to dry after use and before cleaning

Answer 1

A Use of a central reprocessing area for all instrument cleaning
Rationale: A central reprocessing area will have the highest efficacy of medical instrument cleaning because it will often have specialized cleaning equipment and because employees in this area specialize in cleaning equipment; they even may be certified in doing this.

Question 2

Inadequate sterilization of surgical instruments and tubing may result in which of the following adverse events after cataract surgery?

a. Toxic Shock Syndrome
b. Posterior Segment Syndrome
c. Anterior Syndrome
d. Toxic Anterior Segment Syndrome

Answer 2

D Toxic Anterior Segment Syndrome
Rationale: Toxic Anterior Segment Syndrome (TASS) is an acute inflammation of the eye that can occur following cataract surgery. A variety of substances have been implicated as causes of TASS and include impurities of autoclave steam, heat stable endotoxin, and irritants on the surfaces of intraocular surgical instruments. General principles of cleaning and sterilizing intraocular surgical instruments have been published and should be followed.

Question 3

One disadvantage of liquid sterilization is: a. Liquid sterilants are highly toxic and items must be aerated before use b. It is a high heat process so it may not be used on heat-labile items c. It is not an appropriate process for critical items d. Items cannot be wrapped during the sterilization process so sterility cannot be maintained during storage

Answer 3

D Items cannot be wrapped during the sterilization process so sterility cannot be maintained during storage
Rationale: Liquid sterilization uses glutaraldehyde, hydrogen peroxide, or peracetic acid to sterilize items that are critical and are heat-sensitive. This is a liquid immersion process so items cannot be wrapped during the sterilization process. In addition, items may need to be rinsed after the process so sterility is not maintained in the rinsing, drying, and storage phases. Therefore, this method of sterilization is used only when an item cannot be sterilized in any other manner.

Question 4

During infection control rounds in the emergency department, the manager tells you that they will be doing endovaginal ultrasounds soon and would like to use probe covers to speed up the cleaning process. You inform the manager that:

a. Using a probe cover will eliminate the need to high level disinfect the probe
b. Using a probe cover will reduce the amount of time needed to clean the probe
c. Using a probe cover is acceptable, but high level disinfection is still required
d. Using a probe cover is acceptable, but this device requires steam sterilization

Answer 4

C Using a probe cover is acceptable, but high level disinfection is still required
Rationale: A recent study showed that a considerable number of ultrasound probes are contaminated with human papilloma virus (HPV). Endovaginal ultrasound probes are consider semicritical items (even if covered with a sheath or probe cover) and require high level disinfection

Question 5

Which of the following practices have studies shown is most likely to result in improved infection prevention?

a. Strictly adhering to the EPA-registered product label contact time for low level disinfection of environmental surfaces
b. Utilizing a one minute contact time for low level disinfection of environmental surfaces regardless of the EPA-registered product label contact time
c. Thoroughly cleaning and disinfecting all surfaces in a room that have potentially come into contact with hands
d. Thoroughly cleaning and disinfecting all high touch surfaces in a room

Answer 5

C Thoroughly cleaning and disinfecting all surfaces in a room that have potentially come into contact with hands
Rationale: Studies have shown that less than half of all surfaces and equipment that may be contaminated are properly cleaned during a terminal cleaning. Any surfaces or equipment that may have come into contact with hands have the potential to be contaminated; this is inclusive of but also beyond surfaces designated as “high touch.”

Question 6

The director of surgical services has received a call from a neurosurgeon who would like to schedule a brain biopsy on a person suspected of having Creutzfeldt-Jakob Disease (CJD). The staff have expressed concern cleaning and sterilizing the surgical instruments. You response is:

a. Surgical instruments are very expensive and should be cleaned and sterilized after the procedure
b. The recommendations are unclear as to how to clean and sterilize instruments
c. There are no special requirements for cleaning and sterilization of surgical instruments
d. The instrument used in these cases require special processing

Answer 6

D The instrument used in these cases require special processing
Rationale: Contaminated surgical equipment or electrodes in the brain have transmitted infectious prions from one patient to another. In these instances, standard sterilization methods have been inadequate. Instruments used in these cases will require special processing; environmental cleaning and disinfection in surgery

Question 7

You have been asked to do an in-service for Environmental Services on cleaning procedures. Which of the following is the best practice for cleaning a patient room?

1) Clean the patient zone first, and then the perimeter of the room
2) Clean the perimeter of the room first, and then the patient zone
3) Clean items that are low to the floor first and then work your way up to higher items
4) Clean items that are higher up first, and then work your way down to lower items

a. 1, 3
b. 2, 3
c. 1, 4
d. 2, 4

Answer 7

D 2, 4
Rationale: Cleaning should be carried out starting from the least soiled area (outside of the patient zone) and moving toward the most soiled area. Surfaces that are higher up should be cleaned first so that the dust from those surfaces does not contaminate items underneath that had already been cleaned.

Question 8

The purpose of cleaning medical devices before sterilization or high level disinfection is to:

a. Reduce bio-burden
b. Add an additional step to the process
c. Replace the sterilization process
d. Increase the amount of time it takes to clean an endoscope

Answer 8

A Reduce bio-burden
Rationale: Items must be cleaned with water and detergents or enzymatic cleaners before processing. Cleaning reduces the bio-burden and removes foreign material that interferes with the sterilization process by acting as a barrier to the sterilization agent

Question 9

The purpose of including a biological indicator (BI) in an autoclave load is:

a. To determine whether the items being autoclaved are properly sterilized, which is indicated by a positive BI result
b. To determine whether the items being autoclaved are properly sterilized, which is indicated by a negative BI result
c. To determine whether the items being autoclaved are properly cleaned, which is indicated by a positive BI result
d. To determine whether the items being autoclaved are properly cleaned, which is indicated by a negative BI result

Answer 9

B To determine whether the items being autoclaved are properly sterilized, which is indicated by a negative BI result
Rationale: A biological indicator is a standardized, contained population of microbes that is included in a sterilization cycle to indicate whether the cycle was successful. The BI may contain spore-forming bacteria or other highly resistant microbes, and sterilization should render these microbes inactive. After sterilization, a BI is incubated at the optimum temperature and time for growth of the microbe. A positive result occurs from microbial growth, which indicates that the sterilization cycle was not optimal for inactivation of all microbes.

Question 10

In an effort to reduce cost and decrease turn around time, the endoscopy manager has asked if the enzymatic detergent can be used for multiple patients. Your response is:

a. It is acceptable to reuse the detergent
b. The enzymatic detergent must be discarded after each use
c. There are no recommendations on reuse of the detergent d. It is not necessary to use an enzymatic detergent for endoscopes

Answer 10

B The enzymatic detergent must be discarded after each use
Rationale: The CDC recommends that the enzymatic detergent be discarded after each use since these products are not antimicrobial and will not retard microbial growth.

Question 11

An OR team was using a unique surgical instrument on a patient and the instrument was accidentally dropped on the floor. The team needs to reprocess it as quickly as possible to finish the surgery and would like to use Immediate-Use Steam Sterilization (IUSS). Which of the following is the best recommendation for this?

a. The team must clean and inspect the instrument before proceeding with IUSS
b. The team can proceed with IUSS without prior cleaning and inspection of the instrument since it will be used on the same patient
c. There is no need to use IUSS as the team can simply soak the instrument in ten percent bleach for 10 minutes
d. There is no situation in which IUSS is acceptable

Answer 11

A They must clean and inspect the instrument before proceeding with IUSS
Rationale: Immediate-Use Steam Sterilization (IUSS) allows for rapid reprocessing of an instrument in the event that a replacement that underwent standard sterilization is not available. This method is not intended to be used regularly to cut down on turnaround time of instrument reprocessing or to replace the need for back-up instruments. Instruments that will be processed by IUSS must be cleaned thoroughly and inspected, as they would if they were undergoing standard processing

Question 12

Types of tissue consider at high risk for CJD include: 1) Heart 2) Blood 3) Eye 4) Brain a. 1, 4 b. 1, 3 c. 3, 4 d. 2, 4

Answer 12

C 3, 4
Rationale: Tissues known to be highly infectious include brain, dura matter, pituitary tissue spinal cord and eye; tissues with low infectivity include lung, liver, kidney, spleen, lymph and CSF

Question 13

Which of the following describes the correct storage to maintain sterility of reprocessed items?

a. At least 12 inches below the ceiling, at least six inches above the floor, at least one inch from the outside wall, and on a rack with a solid bottom
b. At least 18 inches below the ceiling, at least six inches above the floor, at least one inch from the outside wall, and on a rack with a solid bottom
c. At least 18 inches below the ceiling, at least eight inches above the floor, at least two inches from the outside wall, and on a rack with a solid bottom
d. At least 18 inches below the ceiling, at least eight inches above the floor, at least one inch from the outside wall, and on a rack with a solid bottom

Answer 13

C At least 18 inches below the ceiling, at least eight inches above the floor, at least two inches from the outside wall, and on a rack with a solid bottom
Rationale: Proper storage of sterile, reprocessed items is critical for maintaining sterility. Items should be stored at least 18 inches below the ceiling and eight to ten inches above the floor. Storage should be at least two inches from the wall and if a rack is used then it should have a solid bottom to avoid contamination of items from dust on the floor.

Question 14

Prior to opening a sterile package, the end user should inspect the package for: 1) Tears 2) Moisture 3) Date of manufacture 4) The name of the person who packaged the kit a. 1, 2 b. 2, 4 c. 3, 4 d. 1, 3

Answer 14

A 1, 2
Rationale: Before use, sterile packages should always be inspected for signs of contamination such as moisture, tears, or discoloration in addition to the expiration date.

Question 15

Ultrasonic cleaners are used for: a. Removing gross soil from an instrument b. High-level disinfection of instruments c. Sterilization of instruments d. Fine cleaning of instruments

Answer 15

D Fine cleaning of instruments
Rationale: Ultrasonic cleaners use sound waves to create bubbles that disrupt small particles that may exist in hard-to-clean places on instruments. Ultrasonic cleaners may be used after initial cleaning that removes all visible and accessible soiling is carried out and before final disinfection or sterilization, following manufacturer’s recommendations

Question 16

Aseptic technique is defined as: a. No touch technique b. A process used in the operating room c. An absence of organisms d. The process for keeping away disease producing organisms

Answer 16

D The process for keeping away disease-producing organisms
Rationale: Aseptic techniques, defined as the process for keeping away disease-producing micro-organisms, may be used in any clinical setting. It is implemented to protect the patient by minimizing contamination to reduce the risk for infection.

Question 17

Which of the following indicators is most accurate for assessing whether surgical instruments have been processed correctly in a steam sterilization cycle: a. Autoclave tape b. Chemical indicator c. Biological indicator d. The cycle indicator on the steam sterilizer

Answer 17

C Biological indicator
Rationale: A biological indicator is the only method of assuring that a steam sterilizer has reached the correct conditions to ensure sterility of products. Use of a biological indicator provides reliable, qualitative evidence that all sporeforming organisms have been inactivated during the sterilization cycle

Question 18

You have recently accepted a position at a free standing endoscopy center. After reviewing the policy and procedures, you discover that the last time staff competency for cleaning and disinfecting endoscopes was completed was three years ago. Your next step is:

1) Schedule a meeting with the facility administrator to discuss your findings
2) Do not worry about it because this happened before you worked there
3) Develop competencies for cleaning and disinfection of endoscopes
4) Assume that it is not a problem because there have been no outbreaks at the center
a. 1, 3
b. 2, 4
c. 3, 4
d. 2, 3

Answer 18

A 1, 3
Rationale: Staff should receive training on the safe use and reprocessing of the equipment and be competency tested. Infection control rounds and audits should be done annually. The CDC recommends that competency testing pf personnel reprocessing endoscopes should be done on a regular basis for example on hire and annually.

Question 19

A technician in the OR has reported an infestation of fruit flies in the sterile instrument storage room. The sterile packs were temporarily removed and pest management was called in to eradicate the flies. The OR staff want to know whether they can use the sterile packs. Which of the following is the best response? a. The OR staff can use the packs without any reprocessing because there are no flies visible on the outside of the packs b. The OR staff can use the packs without any reprocessing if they open a test pack and don’t find any flies inside it c. The OR staff don’t need to repack the items but they do need to run the packs through the sterilizer again d. They need to completely reprocess all of the items that were in the affected room

Answer 19

D They need to completely reprocess all of the items that were in the affected room
Rationale: The presence of any type of vermin can affect the integrity of the packaging and contaminate the contents. Fruit flies are small enough to crawl into the sterile packs and potentially contaminate the instruments. They could also become trapped in the packs and leave debris on the instruments. The instruments should be unwrapped, visible inspected, cleaned if necessary, and reprocessed.

Question 20

Which of the following items can generally be reprocessed by only using low-level disinfectant: a. Blood pressure cuffs b. Anesthesia equipment c. Bronchoscopes d. Surgical instruments

Answer 20

A Blood pressure cuffs
Rationale: Non-critical items may generally be reused after being cleaned with a low-level disinfectant. These are items that only come into contact with intact skin and not mucous membranes. Low level disinfectants include 70 to 90 percent alcohol, improved hydrogen peroxide, and quaternary ammonium compounds.

Question 21

Your endoscopy unit has experienced an outbreak associated with bronchoscopes. The CDC recommends that outbreaks in this setting be reported to which agencies:

1) The Joint Commission
2) Centers for Medicaid/Medicare Services
3) The Food and Drug Administration
4) The bronchoscope manufacturer

a. 1, 2
b. 2, 3
c. 3, 4
d. 2, 4

Answer 21

C 3, 4
Rationale: The CDC recommends that endoscopy-associated infections be reported to the person responsible for infection prevention at the facility; the physician responsible for the care of the patient; the appropriate public health agency (which is the FDC or CDC); and the manufacturer(s) of the endoscope, disinfectant/sterilant, and automated endoscope washer-disinfector (if used).

Question 22

According to AAMI ST79, which of the following are among the recommendations for testing of mechanical cleaning equipment in order to verify adequate cleaning?

1) Verification should be carried out monthly
2) Verification should be carried out upon installation
3) Verification should be carried out after major repairs
4) Verification should be carried out when changing cleaning chemistry
a. 1, 2, 3, 4
b. 1, 2, 4
c. 1, 2, 3
d. 2, 3, 4

Answer 22

D 2, 3, 4
Rationale: Mechanical cleaning equipment uses automated cleaning and rinsing to remove soiling from items. According to AAMI ST79, verification of mechanical cleaners should be carried out weekly, and preferably daily. It should also be carried out upon installation of the equipment, after major repairs, and all cycles should be tested when changing cleaning chemistry.

Question 23

A biological indicator that was included in a load of surgical implantables has indicated a failure. You are able to deduce that this was due to operator error, as this one load was not run on the correct cycle. Which of the following actions should you take?

a. No action is needed as the implantables did go through a sterilizer cycle
b. The load with the positive indicator must be reprocessed
c. A recall must be initiated; any loads of implantables run by the technician who ran this load must be reprocessed
d. A recall must be initiated; any loads of implantables run by any technician must be reprocessed

Answer 23

B The load with the positive indicator must be reprocessed
Rationale: When a biological indicator shows a sterilization process failure, it is important to try to deduce the source of the failure. If the failure is the result of a single load that was not run on the correct cycle, then no recall is needed. The load that was not processed correctly must be reprocessed

Question 24

Which of the following are used for sterilization of medical instruments?

1) Gravity-displacement steam sterilizer
2) Pasteurizer
3) Ethylene oxide sterilizer
4) Ultrasonic cleaner

a. 1, 2
b. 1, 3
c. 1, 2, 3
d. 1, 2, 3, 4

Answer 24

B 1, 3
Rationale: Sterilization of instruments results in the instruments being free of all microbes, including spores. This can be achieved through the use of various types of steam sterilizers; gas sterilizers including those that use ethylene oxide gas, ozone, and hydrogen peroxide gas or vapor; and liquid immersion in chemical sterilants.

Question 25

The endoscopy manager has asked for your guidance in finding a location to store sterile supplies. Your response is:

a. The room must be positive pressure with a temperature of no greater than 65°F, with a relative humidity of less than 70 percent
b. The room must be positive pressure with a temperature of approximately no greater than 75°F, with a relative humidity not to exceed 70 percent
c. The room must be negative pressure with a temperature of 65°F, and a relative humidity of greater than 70 percent
d. There are no specific requirements for storing sterile supplies

Answer 25

B The room must be positive pressure with a temperature of approximately 75°F, with a relative humidity not to exceed 70 percent
Rationale: The sterile storage area should be a limited access area with a controlled temperature (may be as high as 75°F) and relative humidity (30 to 60 percent in all work areas except sterile storage, where the relative humidity should not exceed 70 percent).