Antibiotic therapy and Antibiotics Affecting Cell Wall Flashcards Preview

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Flashcards in Antibiotic therapy and Antibiotics Affecting Cell Wall Deck (40)
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What are some examples of gram- positive bacteria?

staph, strep, and enterococci


What are some examples of gram-negative bacteria?

E. coli, pseudomonas, salmonella


Why is culture and sensitivity testing so important before administering antibiotic therapy?

By identifying the microorganisms present in the infection and what antibiotic they are sensitive to we can prescribe the best antibiotic to eradicate the infection.


What does it mean that there is no antibiotic developed yet that is selectively toxic?

This means that an antibiotic that only attacks one type of microorganism has not been invented yet, so all of them have some affect to the hosts cells (normal flora). So they can end up attacking our normal flora MAINLY in our mouth, GI tract, and vagina. This can lead to what is called SUPRAINFECTIONS.


what is a broad-spectrum antibiotic? What are patients on these at a higher risk for?

kills a large variety of different bacteria

They are at a higher risk for suprainfections because they kill more of our normal flora.


What is a narrow-spectrum antibiotic? Is there a risk for suprainfections with these?

These kill a smaller variety of bacteria

There is a much lower risk for suprainfections with these.

By being able to identify specific antigens and having the ability to prescribe an antibiotic that is more specific to that bacteria the risk for suprainfections can be drastically lowered.


What are bacteriocidal antibiotics?

These antibiotics kill bacteria


What are bacteriostatic antibiotics?

These slow the growth of the bacteria allowing for the hosts own immune system to destroy the bacteria.


Are there some situations where a culture and sensitivity cant be done in time and the patients may need to be started on broad spectrum antibiotics before the pathogen is identified? What are the risks with this?


this will increase the patients risk for a suprainfection


What is a key thing to do when taking a culture and sensitivity?

PREVENT CONTAMINATION, if contaminated an inaccurate result may


What is culture and sensitivity exactly? What is the best time to obtain this?

This is when a sample of the bacteria is obtained and cultured to grow, once the bacteria have colonized they are checked for sensitivity to certain antibiotics.

the best time to obtain this is before antibiotic therapy is started


So in a scenario where someone is transferred to the unit with a prescription for an antibiotic and culture and sensitivity to be taken, what should the nurse do?

Hold the antibiotic until the culture and sensitivity has been taken and reported before antibiotics are administered, if it is practical. This means that a culture and sensitivity must be done in a timely manner. However, sometimes antibiotics will be ordered to be administered before culture and sensitivities are done or reported back.


what are some factors that affect antibiotic therapy?

immunocompromised - may need strong bacteriocidals (even ones reserved for severe infections)

sites of infection (brain & CSF are hard to treat because of BBB.... infected skin lesion with poor circulation)

age - infants/older adults have an increased risk for toxicity (impaired metabolism and excretion...kidney and liver function)

Pregnancy - many are pregnancy category D (gentamicin and tetracyclines)

breastfeeding - avoid while on antibiotics


Describe acquired resistance.

drug resistant bacteria/big in nosocomial infections (strong bacteria that arent killed in hospital setting live to become resistant)

NEED TO TAKE REQUIRED DOSE FOR FULL REGIME, only weak ones destroyed, strong one lives to grow and become resistant


Why was vancomycin created?

Vancomycin was created due to methicillin resistant staphylococcus aureus (MRSA) and drug resistance in penicillin and cephalosporins


Is there a bacteria that is resistant to vancomycin?


vancomycin resistant enterococci (VRE)


What is the best way to prevent resistance to antibiotics?

doses should be high enough and for a long enough duration to kill ALL microorganisms (not just the weak ones)

Patient teaching is important!

Combo drugs can help!


What is THE USUAL patient teaching for ALL antibiotics?

dont stop even if you feel better! Take the entire prescribed dose regime

Go to the ED if you experience signs of allergic or hypersensitivity reaction (difficulty breathing, rash, difficulty swallowing)

drink lots of fluids (help flush kidneys, also ill patients need hydration anyways)

Watch for signs of suprainfections - vaginal, mouth, GI (call provider)

dont share medication with other people

small, frequent meals could help with GI effects

keep out of reach of children

report signs of allergic reaction - rash, urticaria


What is the therapeutic response of penicillins?

bacteriocidal by disrupting the bacterial cell wall when dividing; drug of choice for gram-positive


What are penicillins the drug of choice for?

gram-positive bacteria


What are penicillins used as prophylaxis against?

bacterial endocarditis in at-risk clients prior to dental and other procedures.


What are some adverse effects of penicillins?


renal impairment (high doses)

hyperkalemia/dysrhythmias with high doses

cross-sensitivity reaction with cephalosporins (chance of being allergic to chephalosporins if allergic to penicillin and the other way around, (10-20% of population))


What are some nursing considerations for penicillin?

observe clients for 30 minutes after administration (allergic reactions)

monitor for renal impairment

monitor potassium levels and EKG with higher doses - hyperkalemia/dysrhythmias

probenacid (Probalan) (antigout) - delays excretion of penicillin (can be used if not enough penicillin for full dosage regime to increase therapeutic effectiveness time of smaller dose of penicillin by delaying excretion)


What are some patient teaching points for penicillins?


take with a full glass of water one hour before or two hours after a meal

Allergic reactions are common - report rash, pruritis, difficulty breathing/swallowing


What is the therapeutic action of cephalosporins?

bacteriocidal and bacteriostatic depending on the dose used and specific drug; by inhibiting bacterial cell wall synthesis; different generations are effective against different bacteria; BROAD SPECTRUM (RISK FOR SUPRAINFECTIONS)


What are some adverse effects of cephalosporins?

cross-sensitivity with penicillins (same as described in penicillin card)

allergic reactions

pain at IM site (inject deep IM) or thrombophlebitis at IV site (be sure it is diluted, large bore, larger vein (not usually central line))

suprainfections!!! - AAPMC (antibiotic associated pseudomembranous colitis)

bleeding tendencies (cefotetan and ceftriaxone)


what are some nursing considerations for cephalorsporins?

monitor for allergic reactions

Inject deep IM (IM site pain) and make sure solution is diluted (thrombophlebitis at IV site)

monitor for diarrhea and report (AAPMC)

avoid taking with other anticoagulants (cefotetan and ceftriaxone bleeding tendencies)


What are some patient teaching points for cephalosporins?


avoid alcohol for 72 hours after discontinuing the drug - disulfuram reaction (similar to reaction of antabuse (bad hangover feeling))

take with food and keep oral suspension in fridge

avoid taking with anticoagulants (cefotetan and ceftriaxone)


What are the general adverse reactions that can happen with antibiotics?

kidney damage - especially aminoglycosides, vancomycin



neurotoxicity - especially in aminoglycosides and vancomycin

hypersensitivity reactions - (ALL, ESPECIALLY PENICILLIN) most important question to ask if what exactly happens when the drug is taken (making sure it is suggestive of actual allergy, urticaria, rash, anaphylaxis)

Suprainfections (normal flora destroyed) - thrush infections, diarrhea, vaginal yeast infections, AAPMC (c. diff.. causes mucous/pus (sometimes blood) and watery diarrhea with a distinct odor)


Why would antibiotics be prescribed prophylactically?

before procedures (for example GI surgery)