Chap 38 (exam 4) Flashcards Preview

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Flashcards in Chap 38 (exam 4) Deck (85):
1

Antibiotics taken before exposure to an infectious organism in an effort to prevent the development of infection

Prophylactic

2

This class of antibiotics may cause tooth discoloration in children under age 8

Tetracycline

3

Anaphylactic reactions are common with this class of antibiotics

Penicillin

4

Antibiotics that kill bacteria

Bactericidal

5

There is a chance of cross-reactivity between this class of antibiotics and the class penicillin

Cephalosporin

6

The classification for the drug erythromycin

Macrolide

7

This class of antibiotics is commonly used for urinary tract infections

Sulfonamide

8

Antibiotics that inhibit the growth of bacteria

Bacteriostatic

9

An infection that occurs during antimicrobial treatment for another infection and involves overgrowth of a nonsusceptible organism

Superinfection

10

The nurse is reviewing the drugs ordered for a patient. A drug interaction occurs between penicilins and which drugs? Select all that apply:
Alcohol
Oral contraceptives
Digoxin
Nonsteroidal antiinflammatory drugs
Warfarin
Anticonvulsants

Oral contraceptives
Nonsteroidal antiinflammatory drugs
Warfarin

11

Which intervention is important for the nurse to perform before beginning antibiotic therapy?
Obtain a specimen for culture and sensitivity
Give with an antacid to reduce gastrointestinal (GI) upset
Monitor for adverse effects
Restrict oral fluids

Obtain a specimen for culture and sensitivity

12

The nurse will instruct a patient who is receiving a tetracycline antibiotic to take it using which guideline?
It needs to be taken with milk
It needs to be taken with 8 oz of water
It needs to be taken 30 minutes before iron preparations are taken
An antacid should be taken to decrease GI discomfort

It needs to be taken with 8 oz of water

13

A patient is to receive antibiotic therapy with a cephalosporin. When assessing the patient's drug history, the nurse recognizes that an allergy to which drug class may be a possible contrainication to cephalosporin therapy?
Cardiac glycosides
Thiazide diuretics
Penicillins
Macrolides

Penicillins

14

When asked about drug allergies, a patient says, "I can't take sulfa drugs because I'm allergic to them." Which question will the nurse ask next?
"Do you have any other drug allergies?"
"Who prescribed that drug for you?"
"How long ago did this happen?"
"What happened when you took the sulfa drug?"

"What happened when you took the sulfa drug?"

15

Which statement accurately describes the action of antiseptics?
They are used to kill organisms on nonliving objects
They are used to kill organisms on living tissue
They are used to sterilize equipment
They are used to inhibit the growth of organisms on living tissue

They are used to inhibit the growth of organisms on living tissue

16

During a class on health care-associated infections, the nurse shares several facts about these infections. Which statements about health care-associated infections are true? Select all that apply:
They are contracted in the home or community
They are contracted in a hospital or institution
They are more difficult to treat
The organisms that cause these infections are more virulent
The infection is incubating at the time of admission

They are contracted in a hospital or institution
They are more difficult to treat
The organisms that cause these infections are more virulent

17

A patient is receiving imipenem/ cilastatin (Primaxin) and asks the nurse, "Why does that medicine bag have two names listed? Am I receiving two drugs?" What is the best explanation for the patient?

Imipenem/ cilastatin (Primaxin) does contain 2 drugs, but one of the drugs (cilastatin) works to prevent the antibiotic (imipenem) from being destroyed by bacterial enzymes that can make the antibiotic ineffective

18

Mr. R., a 50-year old banker, is scheduled for a colon surgery tomorrow. The surgeon is planning to administer a prophylactic antibiotic. What drug is frequently used for this purpose, and why?

Cefoxitin (Mefoxin) is frequently used in patients undergoing abdominal surgeries because it can effectively kill intestinal bacteria, including anaerobic bacteria

19

Sean is a 19 year old college freshman who has been diagnosed with gonorrhea. The provider has prescribed doxycycline therapy. During the nursing assessment, Sean discusses his diet, which includes "lots of meat, milk and veggies." Sean also tells the nurse that he jogs frequently and is a member of the tennis team.
In addition to instruction about sexually transmitted infections, what patient teaching about the medication does Sean require?
A few days late, Sean calls and complains of an upset stomach and diarrhea. What does the nurse suspect might be wrong with Sean?

Sean must not take the doxycycline with milk because that can result in a significant reduction in the absorption of the drug. Also, Sean needs to be aware that tetracyclines can cause photosensitivity; he needs to avoid direct exposure to sunlight and use sunscreen and/ or protective clothing.
The diarrhea is probably the result of alteration of the intestinal flora caused by the drug therapy.

20

Sandra has bronchitis and has been taking an antibiotic for 1 week. She calls the nurse and complains of severe genital itching and a whitish discharge in her vaginal area. What has happened, and what caused it?

She is experiencing a superinfection because the antibiotics she has been taking for her bronchitis have reduced the normal vaginal bacterial flora, and the yeast that is usually kept in balance by this normal flora has an opportunity to grow and cause an infection

21

A 78 year old patient admitted to the hospital with a stroke 2 days earlier has developed a urinary tract infection. His foley catheter is draining urine that is cloudy and dark yellowish-orange with a strong oder. He is receiving an intravenous heparin infusion and has a history of type 2 diabetes. The physician orders co-trimoxazole (Bactrim).
What will the nurse assess before giving this medication?

He needs to be assessed for renal problems and blood dyscrasias. Also, the use of co-trimoxazole is contraindicated in cases of known drug allergy to sulfonamides or chemically related drugs such as sulfonylureas (used for diabetes), thiazide and loop diuretics, and carbonic anhydrase inhibitors.

22

A 78 year old patient admitted to the hospital with a stroke 2 days earlier has developed a urinary tract infection. His foley catheter is draining urine that is cloudy and dark yellowish-orange with a strong oder. He is receiving an intravenous heparin infusion and has a history of type 2 diabetes. The physician orders co-trimoxazole (Bactrim).
Are there any potential drug interactions?

If he is taking a sulfonylurea for his type 2 diabetes, close monitoring ir needed, because sulfonamides can potentiate the hypoglycemic effects of sulfonylureas in patients with diabetes. In addition, although he is currently receiving intravenous heparin and not warfarin, he may be switch to oral anticoagulants soon, so keep in mind that sulfonamides can potentiate the anticoagulant effects of warfarin and lead to hemorrhage

23

A 78 year old patient admitted to the hospital with a stroke 2 days earlier has developed a urinary tract infection. His foley catheter is draining urine that is cloudy and dark yellowish-orange with a strong oder. He is receiving an intravenous heparin infusion and has a history of type 2 diabetes. The physician orders co-trimoxazole (Bactrim).
Why was the particular antibiotic chosen?

These antibiotics achieve very high concentrations in the kidneys, through which they are eliminated. Therefore, they are primarily used in the treatment of urinary tract infections

24

A 78 year old patient admitted to the hospital with a stroke 2 days earlier has developed a urinary tract infection. His foley catheter is draining urine that is cloudy and dark yellowish-orange with a strong oder. He is receiving an intravenous heparin infusion and has a history of type 2 diabetes. The physician orders co-trimoxazole (Bactrim).
Is there antibiotic bactericidal or bacteriostatic? Explain.

Sulfonamides do not actually destroy bacteria but inhibit their growth. For this reason, they are considered bacteriostatic antibiotics. Bactericidal antibiotics kill bacteria

25

A patient is scheduled for colorectal surgery tomorrow. He does not have sepsis, his WBC count is normal, he has no fever, and he is otherwise in good health. However, there is an order to administer an antibiotic on call before he goes to surgery. The nurse knows that the rationale for this antibiotic order is to:
Provide empiric therapy
Provide prophylactic therapy
Treat for a superinfection
Reduce the number of resistant organisms

Provide prophylactic therapy

26

A teenage patient is taking a tetracycline drug as part of treatment for severe acne. When the nurse teaches this patient about drug-related precautions, which is the most important information to convey?
When the acne clears up, the medication may be discontinued
This medication needs to be taken with antacids to reduce GI upset
The patient needs to use sunscreen or avoid exposure to sunlight, because this drug may cause photosensitivity
The teeth should be observed closely for signs of mottling or other color changes

The patient needs to use sunscreen or avoid exposure to sunlight, because this drug may cause photosensitivity

27

A newly admitted patient reports a penicillin allergy. The prescriber has ordered a second-generation cephalosporin as part if the therapy. Which nursing action is appropriate?
Call the prescriber to clarify the order because of the patient's allergy
Give the medication, and monitor for adverse effects
Ask the pharmacy to change the order to a first-generation cephalosporin
Administer the drug with a nonsteroidal antiinflammatory drug to reduce adverse effects

Call the prescriber to clarify the order because of the patient's allergy

28

During patient education regarding an oral macrolide such as erythromycin, the nurse will include which information?
If GI upset occurs, the drug will have to be stopped
The drug needs to be taken with an antacid to avoid GI problems
The patient needs to take each dose with a sip of water
The patient may take the drug with a small snack to reduce GI irritation

The patient may take the drug with a small snack to reduce GI irritation

29

A woman who has been taking an antibiotic for a UTI calls the nurse practitioner to complain of severe vaginal itching. She has also noticed a thick, whitish vaginal discharge. The nurse practitioner suspects that:
this is an expected response to antibiotic therapy
The UTI has become worse instead of better
A superinfection has developed
The UTI is resistant to the antibiotic

A superinfection has developed

30

The nurse is reviewing the order for wound care, which include use of an antiseptic. Which statements best describe the use of antiseptics? Select all that apply:
Antiseptics are appropriate for use on living tissue
Antiseptics work by sterilizing the surface of the wound
Antiseptics are applied to nonliving objects to kill microorganisms
The patient's allergies must be assessed before using the antiseptic
Antiseptics are used to inhibit the growth of microorganisms on the would surface

Antiseptics are appropriate for use on living tissue
The patient's allergies must be assessed before using the antiseptic
Antiseptics are used to inhibit the growth of microorganisms on the would surface

31

Sulfonamides mechanism of action

Compete w/ PABA for tetrahydropteroic acid synthetase, preventing bacterial synthesis of folic acid, inhibiting bacteria growth
Bacteriostatic
Antimetabolites

32

Sulfonamides indications

Gram positive organisms
Gram negative organisms

33

Sulfamthoxazole w/ trimethoprim

Co-trimoxazole
Bactrium
5:1 ratio
Oral & injectable
Duration 12 hours
Indications: UTIs, respiratory tract infections, prophylaxis & treatment of opportunistic infections in pts w/ HIV
Susceptible organisms: Enterobacter spp, E. coli, Klebsiella spp, Proteus mirabilis, Proteus vulgaris, S areus

34

Sulfonamides Contraindications

Drug allergy
Pregnant women
Infants younger than 2 months

35

Sulfonamides adverse effects

Allergic reaction- typically delayed cutaneous reaction- fever, rash, photosensitivity
Mucocutaneous complications
GI complications
Hepatic complications
Renal complications
Hematologic complications
Blood effects: agranulocytosis, aplastic anemia, hemolytic anemia, thrombocytopenia
GI effects: nausea, vomiting, diarrhea, pancreatitis, hepatotoxicity,
Integumentary effects: epidermal necrolysis, exfoliative dermatitis, steven-johnson syndrome, photosensitivity
ConvulsionsCrystalluria
Toxic nephrosis
Headache
Peripheral neuritis
Urticaria
Cough

36

Sulfonamides interactions

Potentiate hyperglycemic effects of sulfonylureas in diabetes
Potentiate toxic effects of phenytoin
Potentiate anticoagulant effects of warfarin (lead to hemorrhage)
Increases likelihood of cyclosporine-induced nephrotoxicity
May reduce efficacy of oral contraceptives

37

What are the beta-lactam antibiotic subclasses?

Penicillin
Cephalosporins
Carbapenems
Monobactems

38

What are the subgroups of the penicillins?

Natural penicillin
Aminopenicillin
Penicillinase-resistant penicillin
Extended-spectrum penicillin

39

what organsims do the penicillins work against

Kill wide variety of gram positive
Some gram negative
Bactericidal

40

What are penicillinases

Beta-lactamases that can inactivate penicillin by opening the beta-lactam ring

41

Penicillins mechanism of action

Inhibit cell wall synthesis
Slide through bacterial cell walls to get to a site of action, penicillin binding proteins & form a defective cell wall that is unstable and easily broken down
Result in lysis of bacterial cells

42

Penicillins Indications

Prevention & treatment of infection caused by susceptible bacteria
Gram positive organisms: Streptococcus spp, enterococcus spp, staphylococcus spp
Natural penicillins have little action against gram negative
Extended spectrum penicillins have excellent coverage for gram positive, negative & anaerobic

43

Penicillins Adverse effects

Allergic reaction (.7-4%)
Urticaria
Pruritus
ANgioedema
Maculopapular eruptions
Eosinophilia
Steven-Johnson syndrome
Exfoliative dermatitis
Macupapular rash
Anaphylactic reaction (.004-.015%)
CNS: lethargy, anxiety, depression, seizures
GI: nausea, vomiting, diarrhea, taste alterations, oral candidiasis (most common effects)
Hematologic: Anemia, bone marrow depression, granulocytopenia
Metabolic: hyperkalemia, hypernatremia, alkalosis

44

Penicillin Interactions

Aminoglycosides: additivity= more effective killing of bacteria
Methotrexate: decreased renal elimination= increased methotrexate levels
NSAIDS: compete for protein binding= more free & active penicillin
Oral contraceptives: may decrease efficacy of the contraceptive
Probenecid: competes for elimination= prolongs penicillin effects
Rifampin: inhibition= may inhibit killing activity of penicillin
Warfarin: reduced vitamin K from gut flora= enhanced anticoagulant effect of warfarin

45

Penicillin G
Penicillin V potassium

3 salt forms: benzathine, procaine, potassium
IV, IM
Benzathine & procaine: longer acting IM, NEVER through IV

46

Nafcillin

Penicillinase resistant penicillin: others are cloxacillin (oral only), dicloxacillin (only oral), oxacillin
Only injectable

47

Amoxicillin

Aminopenicillin
Against some gram positive organisms
Treat infections in ears, nose, throat, GU tract, skin, skin structures
Peds doses sometimes higher
Only oral
Quick onset

48

Ampicillin

3 salt forms: anhydrous (oral), trihydrate (oral), sodium (parenterally)

49

What drug class are cephalosporins practically identical too? In what areas are they practically identical?

Penicillins in:
Mechanism of Action
Drug effects
Therapeutic effects
Adverse Effects

50

How do cephalosporins work?

By interfereing with bacterial cell wall synthesis
Bactericidal
Bind to same penicillin binding proteins as penicillin

51

What spectrum of bacteria do cephalosporins kill?

Broad spectrum
Gram-positive, gram-negative, anaerobic
Level of gram negative coverage increases w/ each generation
Anaerobic only in 2nd generation
NOT active against fungi & viruses

52

Cephalosporins, common adverse effects

Mild diarrhea
Abdominal cramps
Rash
Pruritis
Redness
Edema

53

Cefazolin

Ancef
1st generation cephalosporin
Excellent against gram positive
Limited against gram negative
Parenteral
Prophylaxis & for susceptible staphylococcal infections

54

Cephalexin

Keflex
1st generation cephalosporin
Excellent against gram positive
Limited against gram negative
Only oral

55

Cefoxitin

Mefoxin
2nd generation cephalosporin
Parenteral
Prophylactic antibiotic in pts undergoing abdominal surgery (kill anaerobes & intestinal bacteria)

56

Cefuroxime

Zinacef
2nd generation cephalosporin
Parenteral
Does NOT kill anaerobic bacteria
Oral form= cefuroxime axetil (Ceftin)

57

Ceftriaxone

Rocephin
3rd generation cephalosporin
Extremely long acting
Once daily most time
Pass easily through blood brain barrier
Treat meningitis
IV, IM
NOT given to hyperbilirubinemic neonates or pts w/ severe liver dysfunction
NOT administered w/ calcium infusions

58

Ceftazidime

Ceptaz, Fortaz, Tazidime
3rd generation cephalosporin
Parenteral
Difficult to treat gram negative bacteria
Excellent spectrum
Combo w/ aminoglycoside
Only injectable

59

Cefepime

Maxipime
4th generation cephalosporin
Broad spectrum
Increased activity against Enterobactar spp, & gram positive from 3rd generation
Treat: uncomplicated & complicated UTIs, uncomplicated skin & skin structure infections, Pneumonia
Only injectable

60

Cefaroline

Teflaro
5th generation cephalosporin
Broadest spectrum of activity
Treats MRSA
Indicated: acute skin & skin structure infections, community acquired pneumonia
Only injectable
Adjust doses in pts w/ decreased renal function

61

Carbapenems mechanism of action

Bactericidal
Inhibit cell wall synthesis

62

Carbapenems indicatiosn

Broadest antibacterial action of any antibiotic
Complicated body cavity & connective tissue infections in acutely hospitalized pts

63

Carbapenems hazards?

Drug induced seizure activity
Relatively small %

64

How long are carbapenems infused?

Over 60 minutes

65

Imipenem/ cilastatin

Primaxin
Carbapenems
Imipenem: wide spectrum against gram positive, negative, anaerobic
Cilastatin: inhibitor of an enzyme that breaks down imipenem (dehydroprptidase
Binds to penicillin binding proteins, inhibiting cell wall synthesis
Treatment: bone, joint, skin & soft tissue infections; bacterial endocarditis caused by S aureua; intraabdominal bacterial infections; pneumonia; UTI & pelvic infections; Bacterial septicemia
IM form contains lidocaine
Seizures more likely in elderly & renal impaired pts

66

Meropenem

Merrem
Carbapenem
less active against gram positive
More active against enterobacteriacecae

67

Doripenem

Doribax
Carbapenem
Less seizure potential
Indicated for: intrabdominal infections
Pyelonephritis
UTIs
Pneumonia

68

Aztreoname

Azactam
Monobactam
Active against aerobic gram negative (E coli, Klebsiella spp, Pseudomonas spp)
Bactericidal: inhibits cell wall synthesis, resulting in lysis
TreatL moderately severe systemic infections, UTIs
Injectable
Combine to treat intraabdominal infectios, gynecologic infections
Adverse Effects: rash, nausea, vomiting, diarrheaMacro

69

Macrolides Mechanism of action

Bacteriostatic (high enough concentrations= bactericidal)
Inhibit protein synthesis by binding reversibly to the 50S ribosomal subunits

70

Macrolides Indications

Upper & lower respiratory tract infections
Skin infections
Soft tissue infetions
Syphilis (spirochetal)
Lyme disease (spirochetal)
Gonorrhea (difficult to treat w/ macrolide monotherapy)
Chlamydia, Mycoplasma, Corynebacterium

71

Macrolide adverse effects

Cardiovascular: palpitations, chest pain, OT prolongation
CNS: headache, dizziness, vertigo
GI: nausea, heptatoxicity, heartburm, vomiting, diarrhea, flatulence, cholestatic, jaundice, anorexia, abnormal taste
IntegumentaryL rash, urticaria, phlebitis @ IV site
Hearing loss
Tinnitus

72

Macrolide interactions

Drugs metabolized in liver: delay in metabolic clearance of 1 or more interacting drugs= prolonged effect w/ possible toxicity
Clarithromycin & Erythromycin: not used w/ moxiflaxacin, primozide, thiroidazine, other drugs w/ prolonged OT effect

73

Erythromycin

Can be IV
Absorption enhanced on an empty stomach
Quickly degraded by the acidity of stomach
Bitter taste

74

Azithromycin

Zithromax
Less adverse effects than erythromycin
Treat: upper & lower respiratory tract infections, skin structure infections
Excellent tissue penetration
Long duration of action (once daily)
Take w/ food & decrease rate & extent of GI absorption
Oral & injectable
Prevent & treat of Mycobacterium avium-intracellulare (MAC) complex infections

75

Clarithromycin

Biaxin
Less adverse effects than erythromycin
Treat: upper & lower respiratory tract infections, skin structure infections
Prevent & treat of Mycobacterium avium-intracellulare (MAC) complex infections
Oral
Twice daily
Adults & children older than 6 months
Must not be crushed (extended release)

76

Fidaxomicin

Dificid
Only for treatment of C diff
Adverse effects: nausea, vomiting, GI bleed

77

Telithromycin

Ketek
Ketolides
Derived from erythromycin A
Better acidity & better antibacterial coverage than macrolides
Mechanism of action similar to macrolides
Associated w/ severe liver damage
Very limited use

78

Tetracyclines mechanism of action

Bacteriostatic
Inhibit bacterial protein synthesis by binding to the 30S bacterial ribosome

Ability to bind to chelate divalent (Ca+++, Mg++) & trivalent (Al+++) metallic ions to form insoluble complexes

79

Tetracyclines indication

Skin & soft tissue infection
Intraabdominal infection
Pneumonia
Syphilis
Lyme disease
Treat SIADH
Kill wide range of rickettsia, chlamydia, mycoplasma, gram positive & negative bacteria
Some protozoans
Treat acne

80

Tetracyclines Contraindications

Pregnant women
Nursing mothers
Drug alergy
Not for children younger than 8

81

Tetracyclines Adverse Effects

discolaration of permanent teeth & tooth enamel hypoplasia (Fetuses & children)
Retard fetal skeletal development (if during pregnancy)
Photosensitivity
Diarrhea
Vaginal candidiasis
Reversible bulging fontanelles in neonates
Thrombocytopenia
Possible coagulation irregularities
Gastric upset
Enterocolitis
Maculopapular rash

82

Tetracyclines Interactions

Avoid coadministration w/ milk, antacids, iron salt= significant reduction in oral absorption
Potentiate effects of oral anticoagulants
Antagonize effects of bactericidal antibodies & oral contraceptives
Increased BUN levels

83

Demeclocycline

Declomycin
Tetracycline
Oral use
Photosensitivity
Used for both antibacterial action & ability to inhibit the action of ADH in SIADH

84

Doxycycline

Doryx
Tetracycline
Treat: rickettsial infections: rocky mountain spotted fever, chlamydial & mycoplasmal infections, spirochetal infections, gram negative infections
Prevent & treat anthrax & malaria
Treat acne
Oral & injectable

85

Tigecycline

Tygacil
Reffered to as glycylcycline
Effective against many organism resistan to others in its class
Treat complicated skin & skin structure infections (include MRSA & vancomysin sensitive enterococcus faecalis)
Treat complicated intraabdominal infections
Injections only
adverse effects: nausea and vomiting