Download Pharmacology Ch. 8: Anti-Infective Agents - Antibiotics & Antiprotozoals Use and more Exams Nursing in PDF only on Docsity!
Pharmacology Chapter 8: Anti-Infective
Agents
A client comes to the clinic reporting mouth sores that appear consistent with an oral yeast infection. The nurse should question the client about recent use of: A. antibiotics. B. antivirals. C. oral contraceptive agents. D. antiprotozoals. - ansA. The client is exhibiting signs of a superinfection, which can occur with the use of antibiotics. Superinfections are not associated with oral contraceptives, multivitamins, or anticoagulants. A client has been diagnosed with an infection. The nurse can help to ensure the success of anti-infective treatment by: A. confirming that the medication prescribed is the drug of choice for the specific microorganism. B. teaching the client that significant adverse effects are expected, and must be endured during treatment. C. administering antihistamines, as ordered, to prevent the development of adverse effects. D. monitoring the client closely for signs of arrhythmias or cardiac ischemia. - ansA. In order for treatment to be effective, it is necessary for an anti-infective to be accurately matched to the offending pathogen. Anti-infectives do not normally cause cardiac adverse effects. The client should be taught that adverse effects can be managed and are not necessarily an inevitability that must be endured. Antihistamines do not prevent most adverse effects. A client has been taking antibiotics at home for the treatment of a respiratory infection for the past 6 days, and there is no evident improvement in the infection. Which nursing assessment is most appropriate? A. Assess the client's understanding of the illness. B. Assess the client's adherence to the medication regimen. C. Assess the client's use of herbal or alternative remedies. D. Assess the client's home hygiene. - ansB.
Nonadherence to antibiotic therapy can result in a continuation or exacerbation of the infection. Poor hygiene is a risk factor for the development of infection but is less likely to perpetuate an existing infection that is being treated appropriately with antibiotics. Herbs may be contraindicated but are unlikely to negate the therapeutic effects of an antibiotic. The nurse should gauge the client's understanding of the illness, but this does not have a bearing on the client's lack of improvement. A client is admitted to the hospital with elevated temperature, chills, cough, and fatigue. The health care provider orders a chest x-ray, which indicates pneumonia. The blood cultures also come back positive for a Gram-negative bacillus. The provider orders two antibiotics to be given to the client, one for Gram-negative organisms and one for Gram- positive organisms. Why does the provider not prescribe just one antibiotic for both types of bacteria? A. Broad-spectrum antibiotics can cause antibiotic resistance. B. It is better for the client to be on two medications. C. There is a cost savings when prescribing narrow-spectrum antibiotics. D. There are not any antibiotics available in the United States that treat both bacteria. - ansA. All antimicrobials have the ability to promote the emergence of drug-resistant microbes. However, resistance is more likely to occur in organisms exposed to broad-spectrum drugs. Although the use of antimicrobials promotes the potential for drug resistance to occur, they do not directly cause the resistance. A client is receiving aminoglycoside therapy. The nurse would be alert for: A. lethargy. B. kidney dysfunction. D. loss of vision. D. hallucinations. - ansB. Kidney dysfunction (i.e., nephrotoxicity) is associated with aminoglycosides. Hallucinations are not associated with the use of aminoglycosides. Lethargy is not associated with aminoglycoside therapy. Loss of vision is more commonly associated with neurotoxic agents such as chloroquine. Hearing loss is a possibility with aminoglycosides. A client with acne has been receiving an anti-infective agent for a prolonged period. Initially, the drug was effective, but over time its effectiveness as decreased. What is the nurse's best action? A. Refer the client to the health care provider because the client may be experiencing resistance. B. Assess the client for additional signs of superinfection.
D. broad spectrum. - ansC. A drug that is bacteriostatic does not kill the cell but interferes with its ability to reproduce. Bactericidal drugs cause the death of the cell. Drug resistance is the ability of a pathogen to adapt and no longer be susceptible to an anti-infective. Bacteriostatic activity can be found in both broad- and narrow-spectrum anti-infectives. A female client calls the pediatrician's office because her child reports a sore throat. The nurse anticipates the pediatrician will take what action? A. Order an antibiotic. B. Request a throat culture. C. Request a list of drug allergies. D. Order an antitussive. - ansB. For sore throat, a throat culture for streptococcal organisms should be performed and the results obtained before an antibiotic is prescribed. A nurse is asked to explain the difference between community-acquired infections and nosocomial infections. What response best describes the difference? A. Usually, community-acquired infections are less severe and easier to treat since nosocomial infections often occur in people whose immunity is impaired. B. Usually, nosocomial infections are less severe and easier to treat since community- acquired infections often result from drug-resistant microorganisms. C. There is no epidemiological difference between the infection types; they are simply categorized as community-acquired or nosocomial. D. Only drug-resistant strains of staphylococci, Pseudomonas, and Proteus are categorized as nosocomial infections. - ansA. Infections are often categorized as community-acquired or nosocomial. Because the microbial environments differ, the two types of infections often have different causes and require different antimicrobial treatment. Generally, community-acquired infections are less severe and easier to treat, although antibiotic-resistant strains are increasing (e.g., methicillin-resistant Staphylococcus aureus [MRSA]). Nosocomial infections may be more severe and difficult to manage because they often result from drug-resistant microorganisms and occur in people whose immunity is impaired. Drug-resistant strains of staphylococci, Pseudomonas, and Proteus are common causes of nosocomial infections. A nurse is aware that the concept of selective toxicity is foundational to antimicrobial therapy. Which statement most accurately describes selective toxicity? A. A drug harms microbes without harming human cells. B. A drug's effect on microorganisms is proportionate to dose.
C. Most microbes may be collected from a host and cultured on an alternative medium. D. A drug can be isolated and produced in a controlled manner in a laboratory setting. - ansA. An important principle of antimicrobial therapy is selective toxicity, which is the ability to suppress or kill an infecting microbe without injury to the host. This concept does not denote dose-dependent effects, the ability to culture a microorganism, or the production of a drug. Although the numbers and virulence of microorganisms help determine whether a person acquires an infection, another major factor is: A. the number of effective drugs available for serious or antibiotic-resistant infections. B. the host's ability to defend itself against the would-be invaders. C. infections that tend to recur and involve simple organisms. D. continuous antimicrobial treatment of infections. - ansB. The human body and the environment contain many microorganisms, most of which do not cause disease and live in a state of balance with the human host. When the balance is upset and infection occurs, characteristics of the infecting microorganism and the adequacy of host defense mechanisms are major factors in the severity of the infection and the person's ability to recover. Conditions that impair defense mechanisms increase the incidence and severity of infections and impede recovery. In addition, use of antimicrobial drugs may lead to serious infections caused by drug-resistant microorganisms. Aminogylcoside antibiotics tend to collect in the eighth cranial nerve. The nurse would anticipate that which clinical manifestation may occur from the cranial nerve involvement? A. Slurred speech B. Inability to swallow C. Vertigo D. Blindness - ansC. The aminoglycosides antibiotics collect in the eighth cranial nerve and can cause dizziness, vertigo, and loss of hearing. An adult client has been treated for strep throat with ampicillin by mouth. The client visits the occupational health nurse and states she has vaginal itching. What organism is the cause of the vaginal itching? A. Proteus B. Klebsiella C. Enterobacter D. Candida - ansD.
Vancomycin is the drug of choice to manage infections caused by MRSA. MRSA is resistant to all of the antistaphylococcic penicillins, as well as to ciprofloxacin and clindamycin. Bactericidal - ansSubstance that causes the death of bacteria. Usually by interfering with CELL MEMBRANE STABILITY or with PROTEINS or ENZYMESnecessary to maintain the cellular integrity of the bacteria. Bacteriostatic - ansSubstance that prevents the replication of bacteria. Usually by interfering with PROTEINS or ENZYME SYSTEMS necessary for reproduction of the bacteria. Broad spectrum - ansAntibiotics are effective against a wide range of bacteria. Culture - ansSample of the bacteria. Sputum, cell scrapings, urine. Used to determine the species of bacteria that is causing the infection. Grown in a lab. Narrow spectrum - ansAntibiotics are effective only against very selective bacteria. Prophylaxis - ansTreatment to prevent and infection BEFORE it occurs. Ex: The use of antibiotics in high risk patients to prevent bacterial endocarditis. Ex: The use of antiprotozoals to prevent malaria. Resistance - ansThe ability of pathogens to adapt to an anti-infective to produce cells that are no longer affected by a specific drug. Selective Toxicity - ansAffects the infecting organisms but not the human cells. Some anti-infective medications are more powerful when given in combination. This means that they are: A. antagonistic. B. compatible. C. incompatible. D. synergistic. - ansD. Synergistic drugs are drugs which are more powerful when given in combination. Spectrum - ansRange of bacteria against which an antibiotic is effective Superinfection - ansInfections that occur when opportunistic pathogens invade tissues and cause infections because the normal flora bacteria have been destroyed by antibiotic therapy.
The client is taking an antibiotic for a urinary tract infection. The client asks how the antibiotic interferes with the growth of bacteria. The nurse explains that the antibiotic has the ability to suppress or kill an infecting microbe without injury to the host. This is referred to as: A. host cell reactivity. B. cell-specific immunity. C. selective toxicity. D. homeostasis. - ansC. An important principle of antimicrobial therapy is selective toxicity, which is the ability to suppress or kill an infecting microbe without injury to the host. Selective toxicity is achievable because the drug accumulates in a microbe at a higher level than in human cells; the drug has a specific action on cellular structures or biochemical processes that are unique to the microbe; or an action of a drug on biochemical processes is more harmful to the microbe than to host cells. The hospital nurse is caring for a group of adult clients. For which client should the nurse most likely administer prophylactic anti-infectives? A. A client with diabetic nephropathy who has recently begun dialysis B. A client who has hyperkalemia and who is receiving sodium polystyrene C. A client with colorectal cancer who is pre-operative for a bowel resection D. A client who is undergoing cardiac rehabilitation following a myocardial infarction - ansC. Abdominal surgery is a common indication for antibiotic prophylaxis, since these surgeries present a significant risk for infection. For this reason, a pre-operative client would be more likely to need prophylaxis than a client who has had an MI, a client with renal failure or a client with an electrolyte imbalance. The nurse is assessing a client who has recently been given the first dose of a new anti- infective. What finding should lead the nurse to suspect that the client is experiencing a hypersensitivity reaction? A. The client has a facial and trunk rash. B. The client is experiencing vertigo. C. The client's blood pressure is 141/88 mm Hg. D. The client recently had an episode of diarrhea. - ansA. Rash suggests a hypersensitivity reaction. Vertigo may suggest a neurotoxic adverse effect. Diarrhea may occur over time as a result of gastrointestinal adverse effects. A blood pressure that is slightly elevated is not suggestive of hypersensitivity.
When an anti-infective's function is to destroy the infective pathogen, it is classified as: A. bacteriostatic. B. sensitive. C. resistant. D. bacteriocidal. - ansD. Anti-infectives can act to destroy an infective pathogen (bactericidal) or to prevent the pathogen from reproducing (bacteriostatic). Resistance is the ability over time to adapt to an anti-infective drug and produce cells that are no longer affected by a particular drug. Culture and sensitivity testing identify the causal pathogen and the most appropriate drug for treating the infection. When caring for infants and the elderly who are in need of an antimicrobial agent, the nurse is aware that when compared with doses for young and middle-aged adults, these clients may require: A. higher dose. B. the same dose. C. a lower dose. D. the same dose but less frequent. - ansC. Infants and the elderly are the populations most vulnerable to drug toxicity. In the infant, the liver and kidneys are still immature and may have difficulty metabolizing or excreting the drug, which results in accumulation. The same process in the elderly is related to the age of their liver and kidneys, which may no longer be functioning at an optimal level. Prescribers may request lower doses of antimicrobial agents for these two populations to minimize the risk for toxicity. The frequency is important in antimicrobial therapy and would not be decreased. When describing an anti-infective agent with a narrow spectrum of activity, what would the nurse include? A. The drug is highly aggressive in killing the pathogen. B. The drug is selective in its action on organisms. C. The drug is effective in interfering with the cell's reproduction. D. The drug is effective against many different organisms. - ansD. An anti-infective with a narrow spectrum of activity is selective in its action; thus, it is effective against only a few microorganisms with a very specific metabolic pathway or enzyme. Broad-spectrum activity refers to effectiveness against a wide variety of pathogens. Bactericidal refers to a highly aggressive drug that causes cell death. Bacteriostatic refers to a drug's effectiveness in interfering with a cell's ability to reproduce or divide.
Which would be tested to determine parasitic sources of infection? A. Sputum B. Sweat C. Blood D. Stool - ansD. When investigators search for parasitic sources of infection, they may examine stool for ova and parasites.
