Chapter 9

Percentage of iodine in surgical scrubs 97-99% 2-10% 35% 70%

2-10%

Percentage of hydrogen peroxide used in sterilization of delicate instruments 97-99% 2-10% 35% 70%

35%

Percentage of ethyl alcohol in most skin degerming agents 97-99% 2-10% 35% 70%

70%

Percentage of bacteria and fungi (vegetative stages) destroyed by pasteurization 97-99% 2-10% 35% 70%

97-99%

The wound care RN uses hydrogen peroxide in wound cleansing. Which of the following terms best represents the treatment goal with the application of this chemical agent?

Antisepsis

What is the most important action by the RN prior to beginning the dressing change?

Application of gloves

During a surgical procedure, the RN observes a surgeon wearing sterile gloves brush his posterior hand surface on a tray. The tray had been cleaned with a liquid chemical agent. What is the most appropriate action by the RN?

Assertion to the surgeon that a change of gloves is necessary before continuing the procedure

Which of the following are correctly matched? Bactericidal—inhibits the growth of bacteria Bactericidal—kills bacteria Bacteriostatic—inhibits the growth of bacteria Bacteriostatic—kills bacteria

Bactericidal—kills bacteria Bacteriostatic—inhibits the growth of bacteria

100°C, 30 minutes will disinfect but will not sterilize.

Boiling water

Which of the following represent the cellular targets for physical and chemical control agents? Cell membrane Cellular synthesis of DNA and RNA Proteins Lysosomes Cell wall

Cell membrane Cellular synthesis of DNA and RNA Proteins Cell wall

Large-scale disinfection of drinking water Chlorine gas Hypochlorites Iodophors

Chlorine gas

dehydration by exposure to normal room air

Desiccation

Sterilization Destruction of all microbial life including bacterial endospores Reduction of most microbial life on inanimate surfaces Reduction of most microbial life on living tissue Mechanical removal of most microbes from living or inanimate surfaces

Destruction of all microbial life including bacterial endospores

What is the RN's most appropriate action with used needles following the completion of the procedure?

Discarding

Incineration Hot-air oven

Dry Heat

Which of the following would not be killed by standard-concentration hydrogen peroxide?

Endospores

Regarding use of heat to control microbial growth, dry heat at lower temperatures is as effective as moist heat at the same temperature. True False

False

chlorine bleach iodine

Halogens

3% solution is used as an antiseptic for skin and wound cleansing

Hydrogen peroxide

Disinfection in dairies, food processing plants, restaurants, hospitals, homes Chlorine gas Hypochlorites Iodophors

Hypochlorites

Skin and tissue antisepsis Chlorine gas Hypochlorites Iodophors

Iodophors

Such antimicrobials exhibit a range of cellular targets, the _________ selective being the most effective against the widest range of microbes and the _________ selective agents exhibiting specificity in terms of cellular targets and microbial types they are effective against. (2)

Least, most

Decontamination Destruction of all microbial life including bacterial endospores Reduction of most microbial life on inanimate surfaces Reduction of most microbial life on living tissue Mechanical removal of most microbes from living or inanimate surfaces

Mechanical removal of most microbes from living or inanimate surfaces

Antiseptic Silver nitrate Silver sulfadiazine Mercury merthiolate Pure silver ions

Mercury merthiolate

Boiling water pasteurization steam under pressure non-pressurized steam

Moist Heat

Heat applied to beverages to prevent spoilage and kill pathogens. Protocols include holding liquids at 71.6°C for 15 seconds or at 63°C for 30 minutes. Does not sterilize.

Pasteurization

What is the most appropriate method of sterilization for metallic surgical instruments?

Pressurized steam

Which of the following microbes may still be present on sterile surgical instruments?

Prions

From the list below, choose the two most resistant microbial forms. Prions Vegetative bacteria Fungal spores Endospores Enveloped viruses

Prions Endospores

Incorporated into urinary catheters Silver nitrate Silver sulfadiazine Mercury merthiolate Pure silver ions

Pure silver ions

gamma and x-rays UV rays

Radiation

Disinfection Destruction of all microbial life including bacterial endospores Reduction of most microbial life on inanimate surfaces Reduction of most microbial life on living tissue Mechanical removal of most microbes from living or inanimate surfaces

Reduction of most microbial life on inanimate surfaces

Antisepsis Destruction of all microbial life including bacterial endospores Reduction of most microbial life on inanimate surfaces Reduction of most microbial life on living tissue Mechanical removal of most microbes from living or inanimate surfaces

Reduction of most microbial life on living tissue

Topical germicide on mouth ulcers and root canals Silver nitrate Silver sulfadiazine Mercury merthiolate Pure silver ions

Silver nitrate

The RN applies a silver-impregnated dressing to the ulcer. What is the rationale for the use of silver dressings in wound care?

Silver possesses antimicrobial activity.

Used in an ointment on second and third degree burns Silver nitrate Silver sulfadiazine Mercury merthiolate Pure silver ions

Silver sulfadiazine

Requires use of an autoclave. To sterilize, temperature must reach 121°C for a minimum of 15 minutes.

Steam under pressure

Adequate sterilization requires that both _________ and length of ____________ be properly controlled. (1)

Temperature, exposure

Choose the statement that identifies the major disadvantage of both cold and desiccation in terms of microbial control. These methods are technically difficult and labor intensive. These methods may encourage growth of microbial populations. These methods are bacteriostatic rather than bactericidal. These methods produce harmful by-products and are costly.

These methods are bacteriostatic rather than bactericidal.

Requires three successive cycles of exposure to free-flowing steam (100°C) alternating with 24-hour incubation periods. Will not kill endospores.

Tyndallization

a 70% solution is best for denaturing microbial proteins

alcohol

very toxic, but used to disinfect surgical instruments

aldehydes

In addition, many of these agents have ________ - __________ microbicidal action without exhibiting toxicity as well as the ability to sustain a persistent action on inanimate surfaces. (4)

broad-spectrum

Another potential target is the _________, whose surface tension can be reduced by various microbicidal agents resulting in a loss of selective permeability in the cell. (4)

cell membrane

Potential cellular targets of various physical and chemical forms of antimicrobials include the ________, whose synthesis can be blocked by these agents or whose structure can be altered as well. (3)

cell wall

Antimicrobial _________ occur in liquid, gaseous, or even solid forms. (1)

chemicals

used in hand scrubs, prepping skin for surgery

chlorhexidine

Which of the following are physical control methods? phenolics cold dry and moist heat radiation halogens desiccation

cold dry and moist heat radiation desiccation

The ________ of the agent as well as its _______ ____ __________ against microbes also play a role in its ability to inactivate microbes.

concentration, mode of action

Select the appropriate uses of hydrogen peroxide for antimicrobial purposes. contact lens disinfection skin antisepsis prior to surgery sterilization of laboratory glassware low temperature sterilizing cabinets for colonoscopes wound cleansing disinfection of countertops and other environmental surfaces

contact lens disinfection low temperature sterilizing cabinets for colonoscopes wound cleansing

Select two methods that can be used for long-term preservation of microbial cultures. irradiation deep freezing (-70oC to -135oC) filtration pasteurization lyophilization

deep freezing (-70oC to -135oC) lyophilization

disrupt cell membranes, but only rated for low-level disinfection

detergents

Please choose the answer that best completes the blanks of this sentence in the correct order. A(n) _________ would be used to destroy bacteria on a countertop whereas a(n) _________ would be used on skin prior to making an incision. antiseptic; disinfectant antiseptic; sterilant sterilant; disinfectant disinfectant; antiseptic

disinfectant; antiseptic

Select the applications of ethylene oxide sterilization. dried food and spices plastics prepackaged medical devices bacteriologic growth media milk and dairy products

dried food and spices plastics prepackaged medical devices

Select the microorganism that is least resistant to chemical and physical control measures. protozoan cysts enveloped viruses gram-negative bacteria nonenveloped (naked) viruses gram-positive bacteria

enveloped viruses

used to disinfect delicate instruments and plastic materials

ethylene oxide

Choose the microbial control method that neither inhibits nor kills microbes, but instead physically removes them from liquids or air. desiccation lyophilization filtration irradiation cold sterilization

filtration

mercury and silver are examples

heavy metals

In general, __________ temperatures allow _________ exposure times, while _________ temperatures require _________ exposure times. (2)

higher, shorter, lower, longer

Select those items in which microbial growth is controlled by means of osmotic pressure. honey apple cider salt-cured meats milk yogurt jellies

honey salt-cured meats jellies

Choose the method used to sterilize a bacteriologic loop before and after inoculating a culture in the laboratory. hot air tyndallization incineration radiation pasteurization

incineration

The use of chemical agents as germicides is very important in health-related fields today, due to their ability to have rapid action in ________ concentrations and their ability to remain functional when solubolized in water or ___________. (3)

low, alcohol

An antimicrobial agent's adverse effect on cells is known as its __________ (1)

mode of action

The ________ of microbes affects the action of an agent, as does the _________ of the population.

number, composition

Finally, the presence of ________ matter, such as saliva and blood, also inhibit the action of many microbicidal agents.

organic

Other agents are resistant to the inactivating action of __________ _________, while others exhibit noncorrosive, sanitizing, or ________ properties and are affordable and readily available to users. (5)

organic matter, deodorizing

triclosan is a member of this antimicrobial category

phenolics

They range from disinfectants and antiseptics to sterilants and ___________, which are chemicals that can be used to inhibit the deterioration of food products. (2)

preservatives

Finally, physical and chemical agents can interfere with _________ synthesis and activity through denaturation, and they can also disrupt the synthesis or structure of ________. (5)

protein, nucleic acids

Select the advantages of phenolic compounds as antimicrobial agents. remain effective in the presence of organic matter generally nontoxic strongly microbicidal effective against prions

remain effective in the presence of organic matter strongly microbicidal

Select the methods below that illustrate the use of moist heat to control microbes. steam autoclave incineration pasteurization desiccation tyndallization boiling water

steam autoclave pasteurization tyndallization boiling water

Select the statement that describes the antimicrobial activity of chlorhexidine. targets cell membrane components and denatures proteins disrupts peptidoglycan structure destroys endospores interfere with nucleic acid replication and transcription

targets cell membrane components and denatures proteins

The ________ as well as the _______ level of the environment will also influence the action of microbicidal agents.

temperature, pH

An optional measurement used to compare the susceptibility of microbes to heat is the _________, which is defined as the lowest temperature required to kill all microbes in a sample in 10 minutes. (4)

thermal death point

In terms of these strategies, the _______ ________ _______ is defined as the shortest length of time required to kill all test microbes at a specified temperature. (3)

thermal death time

The effectiveness of a particular microbicidal agent is governed by several factors besides ________.

time

The shortest length of time required to kill all test microbes at a specified temperature is the thermal death __________ whereas the lowest temperature required to kill all microbes in a sample within 10 minutes is the thermal death _________. time; point time; temperature window; point point; time

time; point

Select the most disadvantageous characteristic of phenolics. inactivated by organic matter limited in their antimicrobial spectrum toxicity expensive difficult to use

toxicity

Select those characteristics of a chemical control agent that make it a desirable agent. corrosive to metals and plastics water or alcohol soluble and stable cidal to a wide range of microbes, but nontoxic to humans and animal tissue rapidly effective in low concentrations ineffective in the presence of organic matter inexpensive short lived, spontaneously inactivate with time

water or alcohol soluble and stable cidal to a wide range of microbes, but nontoxic to humans and animal tissue rapidly effective in low concentrations inexpensive