Antimicrobial Therapy

bactericidal

lethal to pathogen

bacteriostatic

prevents growth, host has to evenly muster own defenses to kill pathogen

Narrow spectrum

antibacterial treatment, treat limited # of organisms, less likely to disrupt flora, used when pathogen is identified by lab test (culture and sensitivity)

Broad spectrum

antribacterial treatment, “broad side of the barn” treats multiple organisms; more likely to disrupt flora; often used when pathogen is unknown

antiobiotics 2 lethal types of hypersensitivities

anaphylaxis, stevens-johnson syndrome

anaphylaxis signs

bronchospasm and harm to at least one other organ system, shock

stevens-johnson syndrome signs

facial swelling, tongue swelling, hives, skin pain and peeling, red/puple rash, blisters skin and mucous membranes; often lethal, life-altering

antiobiotics less lethal types of hypersensitivities

generalized rash, red neck (or “red man” syndrome)

aminoglycosides (gentamicin) can be toxic to which specific organ(s)

renal & ototoxicity

gentamicin is used for which spectrum

narrow spectrum

vancomycin can be toxic to which specific organ(s)

renal & ototoxicity

chloramphenicol can be toxic to which specific organ(s)

bone marrow

Most all antibiotics can be toxic to

GI which can cause N/V/D and dehydration, often prescribed with probiotics, lactobacillus, and yogurt can help

Which lab test is often done on more dangerous antibiotics

peak and trough, trough done just before drug administration and peak done usually 1-2 hours after drug administration

What ADE is most likely to occur when broad spectrum antibiotics are used

superinfection, normal flora is disrupted and emergence of a new infection (black furry tongue, candidiasis (thrush), vaginitis

Common drug drug interactions with antibiotics

hormonal contraceptives (with some), protein binding competition, liver enzyme competition, liver enzyme competition, antagonism effects, potentiation effects

How can we prevent resistence to antimicrobial drugs?

use a narrow spectrum, use less often, use older antibiotics, complete drug course

How to prevent resistance in hospitals?

Prevent infection (Vaccinations, d/c catheters ASAP), diagnose and treat effectively (target thew pathogen: C&S; access the experts), use antimicrobials correctly (use of software to make choices, avoid contamination of lab specimens, treat infection not colonization, “no to Vanco” drug of last resort), prevent transmission (isolation protocols, handwashing)

What may be done while waiting for C&S?

can send for “gram stain” to help narrow the choice of antimicrobial

antibiotics should not be used as prophylactic for

colds

antibiotics can be used for sore throat if

strep is cultured

antibiotics can be used for bronchitis only if

chronic lung (asthma/COPD)

Antibiotics can be used as prophylaxis for

history of valvular heart disorders prior to dentistry/surgery/obstetrical procedures, group beta strep (genitalia) and pregnancy, immunosuppressed clients, prior to major surgery

When are multiple antibiotics given

organism(s) unknown, infection is severe, immunosuppressed host, prevention of resistence (ex: TB), may decrease toxicity because doses of individual drugs can be lower

Multiple antibiotics downside

increased risk of allergic reactions and superinfections, possible antagonism of effects, increased costs

What do penicillins do?

interfere with cell wall synthesis and bacteria cell division (bactericidal)

penicillin common uses

gram + cocci, rods, anaerobes; pharyngitis, endocarditis, pneumonia, meningitis, syphillis, gonorrhea, URI, UTI, otitis, sinusitis

penicillin V administration

oral, should be taken with food

penicillins ADEs

rash to anaphylaxis, GI (N/V/D), decreased RBCs, superinfection

penicillins teaching

report rash immediately, complete entire amount, if long term CBC to see if it changes, Pen V taken with food

penicillins used in which spectrum

narrow spectrum

ampicillins used in which spectrum

broad spectrum

MRSA infections are commonly acquired

by hospitalized clients - “nosocomial" infection

What is MRSA treated with

IV vancomycin (bazooka antibiotic)

vancomycin actions are similar to

penicillin

vancomycin is used in which spectrum

narrow spectrum

Common uses of vancomycin

MRSA, colitis from antibiotics with + culture for C diff

Vancomycin ADEs

ototoxicity and renal toxicity, red neck syndrome, hypotension/chills/fever, N/V/D, stomatits

Vancomycin nursing implications

High alert double check!, infuse slowly > 60 min on pump, vesicant, peak/trough, asses renal (BUN/creatinine), report tinnitus/diahrrea

cephalosprons are the most

widely used antibiotics

Huge danger in cephalosporin use

name similarities

cefazolin (Ancef) is often used for

clients who are allergic to penicillin, actions are similar to penicillin, but cross sensitivity is 1-15% in those with mild allergy to PCN and should not be given to those with STRONG allergy to penicillin

cefazolin (Ancef) is effective against

E. coli, pre-op/post-op prophylaxis

cefaclor (Ceclor) route

po

cefotetan (Cefotan) route

IV

cefaclor (Ceclor) ADE

bleeding (interference with Vit K), Disulfram/Antabuse reaction with alcohol

tetracyclines spectrum

broad-spectrum

tetracyclines route

PO, IM, IV

tetracyclines ADE

Category D (not for use in pregnancy) interferes with calcification (not for children under 8), photosensitivity, GI: N/V/D, liver

tetracycline uses

broad spectrum, STIs, pharyngitis, UTIs

gentamicin action

inhibits protein synthesis, bacteriostatic in low doses; -cidal in high doses

gentamicin uses

gram -, TB, alternative for MRSA, narrow spectrum

gentamicin ADEs

NOT usually drug of first choice, ototoxicity, renal toxicity, neurotoxicity (weakness/paralysis; dizziness, ataxia)

aminoglycosides nursing implications

C&S to identify pathogen and correct drug strongly reccomended; report hearing loss/ringing in ear/problems with balance/headache; renal function: high fluid intake, I&O, check BUN & creatinine; peak/trough trough needs to be low preferably zero; inactivated by long-acting penicillins (separate doses if both are given)

penicillins and aminoglycosides

not compatable in same IV

erythromycin route and dose

usually po, often dosing is short

erythromycin uses

broad spectrum: staph aureus; pneumonia; good alternative for persons allergic to penicillin

erythromycin ADEs

GI side effects very common, superinfections

erythromycin nursing implications

taken on empty stomach, report severe diarrhea especially in children (>10% weight loss), daily weights to make sure no dehydration

trimethoprin plus sulfamethoxazole use

broad spectrum, UTI, otitis, prostate inflammation

sulfonamides ADEs

Renal: calculi, nephrotoxicity; hematologic: decrease in RBC and WBC; hypersensitivity 3%, photosensitivity; GI: N/V/D may be significant; hyperkalemia

Sulfonamides contraindications

< 2 months, pregnancy - cat D, breastfeeding, clients with renal impairment, cross-sensitivity with: loop diuretics, sulfonylureas (glyburide), NSAIDs

Stevens-Johnson Syndrome mortality

25%

Stevens-Johnson Syndrome sx

fever, general ill feeling, pruritis, joint aches, skin lesions, peeling (palms), not immediate days later

Sulfa drugs should not be given if

there is hypersensitivity to related drugs

Sulfonamides Nursing implications

push fluids, I&O, BUN, creatinine, CBC; empty stomach unless N/V (if with food may need to up dose; Report: sore throat, fever, pallor; photosensitivity

ciprofloxacin (Cipro) route

po usually

ciprofloxacin (Cipro) mechanism and use

Interrupts DNA synthesis; broad-spectrum: E. coli, UTIs, STIs, resp infections, ANTHRAX (prevents disease if anthrax spores are inhaled, taken for 60 days)

ciprofloxacin (Cipro) ADEs

photosensitivity; GI: N/V/D; CNS toxicity: dizziness, confusion, visual disturbances IN ELDERLY; TENDON RUPTURE (ACHILLES) this effect is most likely if elderly and on prednisone

ciprofloxacin nursig implications

photosensitivity: wear clothing that protects against sun & use sunscreen; urine may be brown or orange, stains; push fluids I & O, discontinue if tendon pain/swelling; empty stomach (food will decrease absorption; milk and antacids should be avoided)

Chloramphenicol use

serious, broad spectrum; H. flu influenza resistant to penicillins; fatal blood disorders (sepsis)

Chloramphenicol side effects

fatal aplastic anemia, bone marrow suppression (lowered production of all cells, dose related, reversible), Gray baby syndrome (primature newborns, toxic reaction causing ashen-gray cyanosis, vascular collapse, discontinued immediately), sold OTC in Mexico and other countries, told “its good for baby ear pain”

chloramphenicol nursing implications

CBC is routine, monitor drug levels, not used in infants anymore, most common now: purchased out of country and taken OTC

Pros of multiple antimicrobials

sever infection (meningitis), infection with several pathogens, prevent resistance (TB), decrease toxicity

Cons of multiple antimicrobials

Increase risk of allergy, superinfection, increasd cost, development of incredibly drug resistant microbes