NSG124 EXAM 2 DUE 27TH SEP 2023

NSG124 EXAM 2 DUE 27TH SEP 2023 Selective Toxicity - CORRECT ANSWER-Ability of a drug to injure a target cell or target organism w/o injuring other cells or organisms that are in intimate contact with the target Narrow spectrum antibiotics - CORRECT ANSWER-Active against only a few species of microorganisms broad spectrum antibiotics - CORRECT ANSWER-Active against a wide variety of microbes Antibiotic - CORRECT ANSWER-produced by one microbe and has the ability to harm other microbes Under this definition; only compounds that are actually made by microorganisms qualify as antibiotic Antimicrobial - CORRECT ANSWER-any agent, natural or synthetic, that has the ability to kill or suppress microorganisms Under the definition; no distinction is made between compounds produced by microbes and those made by chemists Result when two antibiotics are used together... - CORRECT ANSWER-may be; additive potentiative antagonist (Some cases) Additive respose - CORRECT ANSWER-antimicrobial effect of the combination is equal to the sum of then effect of the two drugs alone potentiative interactions - CORRECT ANSWER-also called "synergistic interaction" effect of the combination is greater than the sum of the effects of the individual agents Antagonism (between drugs) - CORRECT ANSWER-combination of two antibiotics may be less effective than one of the agents by itself Disadvantages of Antibiotic Combinations - CORRECT ANSWER-1. increased risk of toxic and allergic reactions 2. possible antagonism of antimicrobial effects 3. increased risk of superinfection 4. selection of drug-resistant bacteria 5. increased cost Mixed infection - CORRECT ANSWER-infection caused by more than one microbe Common in brain abscesses, pelvic infections, and infections resulting from perforating of abdominal organs Tuberculosis (TB) - CORRECT ANSWER-infectious disease drug combinations are employed for the specific purpose of supressing the emergence of resistant bacteria Decreased Toxicity - CORRECT ANSWER-Antibiotic combination can reduce toxicity to the host ex; combining flucytosine w/ amphotericin B in the tx of fungal meningitis Enhanced bacterial actions - CORRECT ANSWER-Combination of antibiotics can have greater antibacterial action than a single agent. Combined use of penicillin plus an aminoglycoside in the tx of enterococcal endocarditis Penicillin acts to weaken the bacterial cell wall Amino glycoside acts to suppress protein synthesis Prophylactic use - CORRECT ANSWER-Prophylactic use of antibiotics can decrease the incidence of infection in certain kinds of surgery Procedures where prophylactic efficacy has been documented - CORRECT ANSWERCardiac Surgery peripheral vascular surgery orthopedic surgery Surgery on the GI track Misuses of Antimicrobial Drugs - CORRECT ANSWER--Attempted treatment of viral infections -Treatment of fever of unknown origin -Improper dosage -Treatment in the absence of adequate bacteriologic information -Omission of surgical drainage Common viral infections... - CORRECT ANSWER-mumps, chickenpox, and common cold... do not respond to current available drugs Fever - CORRECT ANSWER-Can be sign of infection but can also signify other diseases (hep, arthritis & cancer) Unless the reason for the fever is proven infection, antibiotics should NOT be used omission of surgical drainage - CORRECT ANSWER-antibiotics may have limited efficacy in the presence of foreign material, necrotic tissue or exudate. When appropriate surgical drainage and cleansing should be performed to promote antimicrobial effects Antimicrobial therapy - CORRECT ANSWER-assessed by monitoring clinical responses and lab results frequency of monitoring depends of severity of infection Signs of Success; reduction of fever and resolution of signs and symptoms related to the affected organ system Labs to monitor; Serum Drug levels (to ensure levels are sufficient for antimicrobial effects and to avoid toxicity from excessive levels) Success of therapy - indicated by disappearance of infectious organisms from post tx cultures (may take hrs or weeks) Broad vs Narrow spectrum - CORRECT ANSWER-Broad = kills everything Narrow= kills specific *** Most useful classification of penicillins is based on an antimicrobial spectrum *** Penicillins - Classification - CORRECT ANSWER-classified by 4 major groups; 1. Narrow Spectrum - that are penicillin sensitive 2. Narrow Spectrum - that are penicillin resistant 3. Broad spectrum penicillins (aminopenicillins) 4. Extended - spectrum penicillins (Antipseudomonal penicillins) Penicillins - Action, Use & Resistance - CORRECT ANSWER-Penicillins weakens cell wall, causing bacteria to take up excessive amounts of water and rupture as a result, Penicillins are generally bactericidal ***important; Penicillins are active only against bacteria that are undergoing growth and division*** Penicillins - Weaken Wall by... - CORRECT ANSWER-2 actions;