NURS 125 Chapter 38 Part 2 PDF

Antibiotics Part 2 KR by Katie Robinson Multidrug-Resistant Organisms Organisms that are Methicillin- Vancomycin- Organisms producing resistant to one or more resistant _Staphylococcus resistant _Enterococcus_ ( extended-spectrum beta- classes of...

Antibiotics Part 2 KR by Katie Robinson Multidrug-Resistant Organisms Organisms that are Methicillin- Vancomycin- Organisms producing resistant to one or more resistant _Staphylococcus resistant _Enterococcus_ ( extended-spectrum beta- classes of antimicrobial aureus_ (MRSA) VRE) lactamases (ESBLs) drugs. MRSA Threat 1 Antibiotic 2 Community Resistance Spread MRSA is becoming MRSA is no longer resistant to all currently confined to hospitals, it available antibiotics. has spread to the community. 3 Staphylococcal Infections Approximately 50% of staphylococcal infections in the community involve MRSA. Multidrug-Resistant Organisms (Cont.) VRE Newer Antibiotics VRE is often seen in urinary tract infections. New antibiotics have been developed to treat VRE and MRSA. Aminoglycosides Overview Origin Administration Natural and semisynthetic antibiotics produced from Poor oral absorption; no oral forms (exception: neomycin). _Streptomyces_ spp. Potency Mechanism of Action Very potent antibiotics with serious toxicities. Bactericidal; prevent protein synthesis. Common Aminoglycosides Gentamicin Neomycin Brand name: Neo-Fradin Tobramycin Amikacin Brand name: TOBI Aminoglycosides: Indications Gram-Negative Synergistic Effects Infections Often used in combination with Effective against gram- other antibiotics, such as beta- negative bacteria, including lactams or vancomycin, for _Pseudomonas_ spp., enhanced effectiveness. _Escherichia coli_, _Proteus_ spp., _Klebsiella_ spp., and _Serratia_ spp. Gram-Positive Resistance Used for certain gram-positive infections that are resistant to other antibiotics. Aminoglycosides: Indications (Cont.) Parenteral Administration Inhalation Therapy Neomycin Exception Aminoglycosides are poorly Can also be given via inhalation for Given orally to decontaminate the GI absorbed through the treatment of lung infections. tract before surgical procedures. gastrointestinal tract and are given parenterally. Aminoglycosides: Adverse Effects 1 Nephrotoxicity 2 Ototoxicity Aminoglycosides can cause Aminoglycosides can cause auditory and vestibular renal damage. impairment. 3 Drug Level 4 Minimum Inhibitory Monitoring Concentration Monitor drug levels to prevent toxicities. The minimum inhibitory concentration (MIC) is important for treatment. Aminoglycosides: Adverse Effects (Cont.) Significant Adverse Effects Other Adverse Effects Ototoxicity and nephrotoxicity are the most significant Headache, paresthesia, fever, superinfections, vertigo, adverse effects of aminoglycosides. skin rash, and dizziness are other possible adverse effects. Aminoglycosides: Therapeutic Drug Monitoring Serum Levels Peak and Trough Serum levels are measured to prevent toxicity. Peak: highest drug levels for once-daily regimens. Trough: lowest to ensure adequate renal clearance and avoid toxicity. Aminoglycosides: Therapeutic Drug Monitoring (Cont.) Postantibiotic Effects Resistance Drug Interactions Resistance to aminoglycosides can Aminoglycosides can interact with Aminoglycosides have a prolonged develop through mutations in other drugs, such as loop diuretics postantibiotic effect, meaning they bacterial genes, leading to and neuromuscular blocking continue to inhibit bacterial growth decreased drug uptake or agents, potentially increasing the even after serum levels have increased inactivation. risk of adverse effects. declined. Quinolones Overview Fluoroquinolones Oral Absorption Also called fluoroquinolones. Excellent oral absorption. Antacid Impact Spectrum of Activity Absorption reduced by Effective against gram- antacids. negative organisms and some gram-positive organisms. Common Quinolones Ciprofloxacin Norfloxacin Brand name: Cipro Brand name: Noroxin Levofloxacin Moxifloxacin Brand name: Levaquin Brand name: Avelox Quinolones: Mechanism of Action 1 Bactericidal 2 DNA Alteration Quinolones are bactericidal antibiotics. Quinolones alter the DNA of bacteria, causing death. 3 Human DNA 4 Bacterial Resistance Quinolones do not affect human DNA. Resistance to quinolones is a growing concern. Quinolones: Indications Gram-Negative Infections Bacteria Treats complicated urinary tract, respiratory, bone and Effective against joint, GI, skin, and sexually _Pseudomonas_ spp. transmitted infections. Anthrax Ciprofloxacin is used to treat anthrax. Quinolones: Interactions 1 Oral Quinolones 2 Dairy Products Antacids, calcium, Dairy products can magnesium, iron, zinc, or interfere with absorption. sucralfate. 3 Enteral Tube 4 Other Interactions Feedings Enteral tube feedings can Probenecid, also affect absorption. nitrofurantoin, and oral anticoagulants. Quinolones: Adverse Effects CNS GI Cardiac Headache, dizziness, insomnia, Nausea, vomiting, diarrhea, Prolonged QT interval. depression, restlessness, constipation, thrush, increased convulsions. liver function study results, others. Quinolones: Adverse Effects (Cont.) Integumentary Other Rash, pruritus, urticaria, flushing. Ruptured tendons, tendonitis, fever, chills, blurred vision, tinnitus. Miscellaneous Antibiotics Clindamycin (Cleocin) Linezolid (Zyvox) Used to treat serious bacterial Used to treat bacterial infections. infections. Metronidazole (Flagyl) Nitrofurantoin (Macrodantin, Furadantin) Used to treat anaerobic bacterial infections. Used to treat urinary tract infections. Miscellaneous Antibiotics New Class: Pleuromutulins Lefamulin (Xenleta) and Retapamulin (Altabax) are two examples of pleuromutilins. Clindamycin Details Indications Adverse Effects Used for chronic bone infections, genitourinary May cause infections, intraabdominal pseudomembranous infections, and other colitis, also known as serious infections. antibiotic-associated colitis, _Clostridioides difficile_ diarrhea, or _C. difficile_ infection. Drug Interactions Potential interaction with vecuronium. Daptomycin (Cubicin) Lipopeptide Class Mechanism of Action Daptomycin is the only drug in the lipopeptide class. Binds to gram-positive cells in a calcium-dependent process. Mechanism of action is not fully understood. Disrupts the cell membrane potential. Colistimethate (Coly-Mycin) Polypeptide antibiotic that disrupts Serious adverse effects can occur. Can cause acute respiratory failure the bacterial membrane of when administered by inhalation. susceptible strains of gram-negative bacteria. Dalbavancin (Dalvance) Lipoglycopeptide Effective Against MRSA Long Half-Life Similar to telavancin, indicated for Extremely long half-life, dosed once skin and skin structure infections Effective against methicillin- weekly. caused by susceptible gram-positive resistant Staphylococcus aureus organisms. (MRSA). Linezolid (Zyvox) New Class Indications Oxazolidinones. Treats vancomycin-resistant _Enterococcus faecium_ (VREF, VRE), hospital- acquired, and skin structure infections, including those with MRSA. Adverse Effects May cause hypotension, serotonin syndrome if taken with SSRIs, and reactions if taken with tyramine-containing foods. Metronidazole (Flagyl) Anaerobic Infections Organisms Treats intraabdominal and Used to treat infections gynecologic infections. caused by anaerobic organisms. Protozoal Drug Interactions Infections Effective against certain Has several potential drug protozoal infections. interactions. Nitrofurantoin (Macrodantin) Indications Considerations Primarily used for UTIs caused by _E. coli, S. aureus, Use carefully if renal function is impaired. Drug Klebsiella_ spp., and _Enterobacter_ spp. concentrates in the urine. Quinupristin–dalfopristin (Synercid) Synercid Mechanism of Action Indications 30:70 combination of quinupristin Used for bacteremia and infections and dalfopristin. Works synergistically to treat infections.caused by VRE. Telavancin (Vibativ) Lipoglycopeptide antibiotic. Treats skin and skin structure infections and pneumonia from gram- positive organisms. Adverse effects include renal toxicity, infusion-related reactions, and QT prolongation. Vancomycin Overview Treatment of Choice Oral Vancomycin Vancomycin is the treatment of choice for methicillin- Oral vancomycin is indicated for the treatment of resistant Staphylococcus aureus (MRSA) and other antibiotic-induced colitis (C. difficile) and for the gram-positive infections. treatment of staphylococcal enterocolitis. Vancomycin Details 1 Red Man Syndrome 2 Neuromuscular Blockers Flushing or itching of head, neck, Additive neuromuscular blocking face, and upper trunk may occur. effects may occur in patients receiving neuromuscular blockers. 3 Infusion Rate 4 Blood Levels Infuse over 60 minutes to avoid Monitor blood levels to ensure hypotension. therapeutic efficacy. Nursing Implications Drug Allergies Hepatic, Renal, Cardiac Function Assess for drug allergies before beginning therapy. Assess hepatic, renal, and cardiac function before beginning therapy. Patient Health History Drug Interactions Assess for potential drug interactions. Obtain a thorough patient health history, including immune status. Nursing Implications (Cont.) Culture Collection Medication Adherence Obtain cultures from Instruct patients to take appropriate sites before antibiotics as prescribed for starting antibiotic therapy. the full duration. Nursing Implications (Cont.) Superinfection Medication Verification Adverse Effects and Assessment Interactions Monitor for signs of superinfection, Verify medication names carefully to Assess and monitor for specific such as fever, itching, cough, prevent errors due to similar- adverse effects and drug lethargy, or unusual discharge. sounding or spelled drugs. interactions associated with each antibiotic class. Monitor for Therapeutic Effects Signs of Improvement Negative Culture Monitor for improvement in signs and symptoms of infection.Monitor for negative culture and sensitivity tests. Look for a return to normal vital signs. Observe for the disappearance of fever, lethargy, drainage, and redness.