Podcast
Questions and Answers
What is kernicterus, a condition that can be caused by sulfonamides in newborns?
What is kernicterus, a condition that can be caused by sulfonamides in newborns?
What is the primary purpose of antimicrobial therapy?
What is the primary purpose of antimicrobial therapy?
Which antibiotic can cause discoloration of developing teeth?
Which antibiotic can cause discoloration of developing teeth?
What is the principal difference between bacteriostatic and bactericidal antibiotics?
What is the principal difference between bacteriostatic and bactericidal antibiotics?
Signup and view all the answers
What is the purpose of the disk diffusion test (Kirby-Bauer test) mentioned in the text?
What is the purpose of the disk diffusion test (Kirby-Bauer test) mentioned in the text?
Signup and view all the answers
What is an important consideration when administering antimicrobials to lactating women?
What is an important consideration when administering antimicrobials to lactating women?
Signup and view all the answers
How does conjugation contribute to the need for new antimicrobials?
How does conjugation contribute to the need for new antimicrobials?
Signup and view all the answers
What is superinfection in the context of antimicrobial therapy?
What is superinfection in the context of antimicrobial therapy?
Signup and view all the answers
Why is it important for nurses to obtain specimens for culture prior to antimicrobial treatment?
Why is it important for nurses to obtain specimens for culture prior to antimicrobial treatment?
Signup and view all the answers
What is a common indication for prophylactic use of antimicrobials?
What is a common indication for prophylactic use of antimicrobials?
Signup and view all the answers
What is a preventive measure to avoid the spread of infection?
What is a preventive measure to avoid the spread of infection?
Signup and view all the answers
What does the minimum inhibitory concentration (MIC) represent in antimicrobial testing?
What does the minimum inhibitory concentration (MIC) represent in antimicrobial testing?
Signup and view all the answers
Which mechanism of action is unique to bacteria and not present in mammals?
Which mechanism of action is unique to bacteria and not present in mammals?
Signup and view all the answers
What is the primary purpose of classifying antimicrobial medications?
What is the primary purpose of classifying antimicrobial medications?
Signup and view all the answers
Why do infants have an increased risk of antimicrobial toxicity?
Why do infants have an increased risk of antimicrobial toxicity?
Signup and view all the answers
What is an invasive procedure that increases the risk of infection?
What is an invasive procedure that increases the risk of infection?
Signup and view all the answers
What is the purpose of adjusting antibiotic dosage according to MIC?
What is the purpose of adjusting antibiotic dosage according to MIC?
Signup and view all the answers
What is an important aspect of evaluating the effectiveness of antimicrobial treatment?
What is an important aspect of evaluating the effectiveness of antimicrobial treatment?
Signup and view all the answers
What distinguishes narrow-spectrum antibiotics from broad-spectrum antibiotics?
What distinguishes narrow-spectrum antibiotics from broad-spectrum antibiotics?
Signup and view all the answers
Why are some sites within the body considered difficult for antimicrobials to reach?
Why are some sites within the body considered difficult for antimicrobials to reach?
Signup and view all the answers
Which type of medications are directly lethal to micro-organisms?
Which type of medications are directly lethal to micro-organisms?
Signup and view all the answers
What is a potential adverse effect of combining antimicrobials?
What is a potential adverse effect of combining antimicrobials?
Signup and view all the answers
What is a common side effect of gentamicin in infants?
What is a common side effect of gentamicin in infants?
Signup and view all the answers
What effect does impairing protein synthesis in bacterial ribosomes have on microbes?
What effect does impairing protein synthesis in bacterial ribosomes have on microbes?
Signup and view all the answers
Study Notes
Selection of Antimicrobials
- Bacteriostatic medications slow the growth of micro-organisms, but the immune system response of phagocytic cells (macrophages, neutrophils) actually destroys the bacteria.
- Three principal factors to consider when selecting an antibiotic: identity of the causative agent, sensitivity of the infecting organism to an antimicrobial, and other factors (location of infection, age, allergies, and immune status of host).
Identification of Causative Agent
- Laboratory testing of body fluids (blood, urine, sputum, and wound drainage) identifies the micro-organism causing the infection.
- Gram stain: technicians examine an aspirate of the body fluid under a microscope to identify the micro-organisms directly.
- Culture: technicians apply the aspirate to a culture medium, where colonies of the micro-organism grow over several days.
Sensitivity of a Micro-organism to an Antimicrobial
- Disk diffusion test (Kirby-Bauer test): determines the degree of medication sensitivity.
- Serial dilution: a quantitative method using several test tubes with varying concentrations of the antimicrobial to determine the amount necessary to treat a specific infection.
- Minimum inhibitory concentration (MIC): the lowest concentration of antibiotic that inhibits bacterial growth completely but does not kill the bacteria.
- Minimum bactericidal concentration: the lowest concentration of the antibiotic that kills 99.9% of the bacteria.
Host Factors
- Immune system: people with an intact immune system require either bactericidal or bacteriostatic antibiotics, while those with immune system compromise need strong bactericidal antibiotics.
- Site of infection: some sites are difficult for antimicrobials to reach, such as cerebrospinal fluid, heart, and purulent abscesses.
- Age: infants and older adults are at increased risk for antimicrobial toxicity due to undeveloped kidney and liver function or reduced medication metabolism and excretion.
Antimicrobial Therapy
- Antimicrobial therapy: the use of medications to treat infections due to bacteria, viruses, or fungi.
- Antimicrobials use selective toxicity to kill or control microbes without destroying host cells.
- Changes in the DNA of micro-organisms (conjugation) produce resistance to multiple existing medications, requiring the creation of new antimicrobials.
Methods of Antimicrobial Actions
- Destroying the cell wall present in bacteria but not in mammals.
- Inhibiting the conversion of an enzyme unique for a particular bacterium's survival.
- Impairing protein synthesis in the bacteria's ribosomes, which are never identical to mammalian cells.
- Disrupting bacterial synthesis or function of DNA and RNA.
- Inhibiting viral replication.
Classification of Antimicrobial Medications
- Narrow-spectrum antibiotics: effective against a few types of bacteria.
- Broad-spectrum antibiotics: effective against a wide variety of bacteria.
- Bactericidal medications: directly lethal to the micro-organism.
Prophylaxis
- Indications for prophylactic use include prevention of infections in clients undergoing surgery, sexually transmitted infections following sexual exposure, and individuals with prosthetic heart valves prior to dental or other procedures.
- Use antimicrobials for individuals who have recurring urinary tract infections.
Preventive Measures
- Perform hand hygiene before and after each client contact to prevent the spread of infection.
- Recognize invasive procedures that increase the risk of infection.
- Encourage clients to maintain an up-to-date immunization status.
- Instruct clients to take the full course of antimicrobials prescribed to prevent medication resistance and recurrence of infection.
- Use infection-control procedures to prevent transmission of resistant micro-organisms.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the fundamentals of antimicrobial therapy, including the use of medications for treating infections caused by bacteria, viruses, or fungi. Learn about selective toxicity, DNA changes leading to drug resistance, and superinfection risks.
