Antimicrobials Flashcards
Define bactericidal vs. bacteriostatic antibiotics.
Bactericidal: Kills bacteria directly (e.g., beta-lactams, vancomycin).
Bacteriostatic: Inhibits bacterial growth, allowing the immune system to eliminate them (e.g., some protein synthesis inhibitors).
What is empiric therapy?
Empiric therapy is starting antibiotic treatment based on clinical judgement before the exact cause of infection is known, especially in emergencies.
What is definitive therapy?
Definitive therapy is antibiotic treatment tailored to a known pathogen based on culture and sensitivity results.
Outline the pathway for treating emergency bacterial infections.
Assess symptoms and severity.
Initiate empiric broad-spectrum antibiotics.
Obtain cultures before antibiotics if possible.
Monitor for improvement.
Switch to narrow-spectrum therapy based on lab results.
What is the mechanism of action of beta-lactam antibiotics (e.g., penicillins, cephalosporins)?
They inhibit bacterial cell wall synthesis by binding to penicillin-binding proteins, leading to cell lysis and death.
What is the mechanism of action of aminoglycosides (e.g., gentamicin)?
They inhibit bacterial protein synthesis by binding to the 30S ribosomal subunit, causing misreading of mRNA.
What nursing care is important for beta-lactam administration?
Monitor for allergic reactions (rash, anaphylaxis).
Assess renal function.
Encourage full course of medication.
Watch for superinfections like C. difficile.
What is the mechanism of action of vancomycin?
It inhibits bacterial cell wall synthesis by binding to D-Ala-D-Ala terminus of cell wall precursors, preventing cross-linking.
What nursing care is important for aminoglycoside administration?
Monitor peak and trough levels.
Watch for nephrotoxicity and ototoxicity.
Ensure adequate hydration.
Use cautiously in renal impairment.
What nursing care is important for vancomycin administration?
Infuse slowly to avoid Red Man Syndrome.
Monitor trough levels.
Check renal function regularly.
Monitor for ototoxicity and nephrotoxicity.
How does antibiotic resistance occur?
Through genetic mutations or acquiring resistance genes (plasmids), allowing bacteria to:
Inactivate drugs (e.g., beta-lactamases).
Alter drug targets.
Pump drugs out (efflux pumps).
What nursing care helps prevent and treat antibiotic resistance?
Administer full course of antibiotics.
Avoid unnecessary antibiotic use.
Educate patients on adherence.
Practice proper hand hygiene and infection control.
How do antiviral medications limit viral disease?
They inhibit steps in viral replication, such as:
Blocking entry/uncoating (e.g., amantadine).
Inhibiting DNA/RNA synthesis (e.g., acyclovir).
Blocking viral protease or neuraminidase enzymes (e.g., oseltamivir).
When are antivirals prescribed for viral infections?
When viruses have specific treatments (e.g., influenza, herpes, HIV).
When symptoms are severe or immunocompromised patients are affected.
Early in infection for maximum effectiveness.
When are antivirals NOT prescribed for viral infections?
For mild or self-limiting illnesses (e.g., common cold).
When the virus lacks an effective treatment.
If given too late in the course of illness.
