Pharmacology and the Nursing Process7: Antibiotics Flashcards

• an infection that is acquired by a person who has not been hospitalized or had a medical procedure within the past year

• contracted in a hospital or institutional setting
• not present/incubated before a hospital admission
• often more difficult to treat because causative microorganisms are often drug resistant and the most virulent

• microbes/ pathogens have mutated to current meds changed adapted making medications/antibiotics less effective

• labs: window of a high and low level in which Rx works the best

• concentration of the least amount of the drug that is in the body/blood and still working

• A property of most antibiotic classes whereby prolonged high plasma drug concentrations are required for effective bacterial kill

• Z-pak (Azithromycin)

• how long a drug stays in the body, how much damage we can do to the pathogen in that period of time
• constant amount of antibiotic in the body to kill that pathogen

• organisms that are resistant to one or more classes of antimicrobial drugs

• methicillin-resistant staphylococcus aureus (MRSA)
• Vancomycin-resistant Enterococcus (VRE)
• organism producing extended-spectrum betalactamases (ESBLs))
• Organisms producing Klebsiella puemoniae carbapenemase (KPC)

• treatment of an infection before specific culture information has been reported or obtained (generally broad spectrum antibiotic used until culture is received)

• antibiotic therapy tailored to treat organism identified with cultures
• have culture back, used antibiotics that microbe is sensitive to

• treatment with antibiotics to prevent an infection, as in intraabdominal surgery or after trauma

• decrease in specific s/s of infection are noted (decrease in fever, elevated WBC, redness, inflammation, drainage, pain)

• s/s of infection do not improve
• pt does not get better---->need to try different antibiotics

• interference with cell wall synthesis
• interference with protein synthesis
• interference with DNA replication
• Acting as a metabolite to disrupt critical metabolic reaction inside the bacterial cell

• kill bacteria
• action of some antibiotics

• inhibit growth of susceptible bacteria, rather than killing them immediately; will eventually lead to bacterial death
• action of antibiotics

• often combined with another drugs (synergistic)
• Sulfamethoxazole w trimethoprim (non sulfa antibiotic)= Bactrim, Septra (commonly used)

• bacteriostatic
• prevents synthesis of folic acid required for synthesis of bacterial purines and nucleic acid
• does not affect human cells or production of folic acid
• only affects bacterial organisms that synthesize their own folic acid

• effective against both gram+ and gram - bacteria
• often used for treatment of UTIs
• URIs
• commonly prescribed for outpatient staphylococcus infections, MRSA

• Blood: thrombocytopenia
• Integumentary: photosensitivity, Stevens-Johnson syndrome
• GI: n/v, diarrhea, pancreatitis
• other: hepatotoxicity, h/a,cough

• Natural pcn: Penicillin G, Penicillin V
• Penicillinase-resistant drugs: nafcillin, colxacillin, oxacillin, dicloxacillin
• Aminopenicillins: amoxicillin (Amoxil), ampicillin (generic only)
• Extended spectrum drugs: carbenicillin, piperacillin, ticarcillin

* generic all -cillins; some trade names don't include -cillin so be careful &know both

• bactericidal
• pcns enter bacteria via the cell wall
• inside the cell wall they bind to pcn-binding protein
• once bound, normal cell wall synthesis is disrupted
• RESULT: BACTERIAL CELL DEATH by cell lysis
• do not kill other cells in body

• prevention and tx of infections caused by susceptible bacteria
• gram + bacteria, some gram - bacteria, some anaerobic bacteria and spirochetes

• allergic reactions to pencilling occur in 0.7% to 4 % of treatment course (urticaria, pruritus angioedema)
• n/v, diarrhea, abd pn
• if pt has a hx of throat swelling/hives from pcn they should not receive cephalosporins; if allergic to pcn there is an ^ risk for allergy to other beta-lactam antibiotics
• if a pt is going to have a reaction it is most likely to happen within the first 15 to 20 min of receiving the antibiotics, good to stay with pt for that period of time

• MANY!
• NSAIDS
• Oral contraceptives
• Warfarin
• ex: coumadin: very loosely protein bound, main drugs knock it off its receptor site

• good gram+ coverage
• poor gram - coverage
• Parenteral and PO
• examples: Cefazolin (Ancef) (IV or IM) & Cephalexin (Keflex) (PO)
• used for surgical prophylaxis, and susceptible staphylococcal infections

• good gram + coverage
• better gram- coverage than first generation but still not great
• ex: Cefoxitin (Qefoxin) (IM &IV) : used prophylactically for abdominal or colorectal surgeries; also kills anaerobes
• ex: Cefuroxime (Zinacef) (Ceftin): surgical prophylaxis, does not kill anaerobes

• most potent group against gram- bacteria
• less active against gram+
• ex: Ceftazidime (Fortaz), Ceftriaxone (Rocephin)

• cephalosporin 3rd generation
• IV & IM
• long half life,
• once a day dosing
• Elimination is primary hepatic
• easily passes meninges and diffused into CSF t treat CNS infections

• cephalosporin 3rd generation
• IV & IM
• excellent gram- coverage
• resistance is limiting when we use it

• broader spectrum of antibacterial activity then 3rd generation, especially against gram+ bacteria
• complicated/uncomplicated UTI >>> Cefepime(Maxipime)

Ceftaroline (Teflaro)

• broader spectrum of antibacterial activity
• effective against a wide variety of organisms (MRSA)

• Similar to pcn
• mild diarrhea, abd cramping, rash, pruritus, redness, edema
• potential cross-sensitivity with penicillins if allergies exist

• wide spectrum: gram - and gram + organisms
• natural and semisynthetic
• bacteriostatic
• inhibits bacterial protein synthesis
• stops many essential functions of bacteria
• binds (chelate) to Ca+++ , Mg++, & Al+++ ions to form insoluble complexes
• dairy products reduce the absorption of tetracycline ^^^^^^^^

• oxytetracycline (Terramycin)
• Tetracycline
• doxycycline (Doryx, Vibramycin)
• Tigecycline (tygacil)

• strong affinity for calcium: discoloration of permanent teeth/tooth enamel in fetuses and children or if nursing infants
• may retard fetal skeletal development if taken during pregnancy
• alteration of intestinal flora: SUPER INFECTION >candida
• diarrhea
• pseudomembranous colitis
• vaginal candidiasis
• gastric upset
• enterocolitis
• maculopapular rash
• others

• poor oral absorption
• very potent antibiotics with serious toxicities
• bactericida; prevent protein synthesis
• kill mostly gram-; some gram +

• gentamicin
• neomycin (neo-fradin)
• tobramycin (TOBI)
• amikacin

• used to kill gram - bacteria
• often used in combination with other antibiotics for synergistic effects (often sulfas)
• used for certain gram + infections that are resistant to other antibiotics
• Poorly absorbed through GI tract, given parentally (exception neomycin)

• given orally to decontaminate GI tract before surgical procedures
• used as an enema for ^ purpose
• used to treat hepatic encephalopathy----->liver induced brain disease come with severe cirrhosis

• Nephrotoxicity (renal damage)
• Ototoxicity (auditory impairment and vestibular impairment @ eighth cranial nerve, high frequency)
• h/a
• paresthesia
• fever
• superinfections
• vertigo
• skin rash
• dizziness

• must monitor drug levels to prevent toxicities
• MIC

• used for anaerobic organisms
• given often in hospital
• intraabdominal and gynecologic infections
• protozoal infections

• treatment choice for MRSA and other Gram+ infectionS
• oral vancomycin is indicated for treatment of antibiotic induced colitis (C.Difficle) and for the treatment of staphylococcal enterocolitis
• must monitor blood levels to ensure therapeutic level and prevent toxicity
• MAY CAUSE OTOTOXICITY AND NEPHROTOXICITY

• Therapeutic: Peak: 20-40 mpg/mL ; trough 5-10mcg/mL
• Toxic level greater than 40 mph/mL

• red man syndrome may occur: flushing/itching of head, neck, face, upper trunk; antihistamine may be ordered to reduce effect (often occurs if vancomycin is given too fast, pt will almost turn purple from nipple line up, should be given with a pump to prevent this )
• additive neuromuscular blocking effects in pt receiving neuromuscular blockers
• should be infused over 60 min
• rapid infusion may cause hypotension

• #1: contradictions to any drug: DRUG ALLERGIES
• LABS: BUN, cretinine, liver function tests
• current medications, supplements, diet, pt health history included immune system status
• any prior health condition that my contraindication to antibiotic use or indicate cautious use
• assess for potential drug interactions

• CULTURE!!!
• 2 separate sites if obtaining blood culture
• if swab culture directly from site of infection

• fever
• perineal itching
• cough
• lethargy
• any unusual discharge

• take with 2000-3000 mL of fluid / 24 hr
• assess RBCs prior to beginning therapy
• take oral does with food

• take oral does with water not juice as acidic fluids may nullify drugs antibacterial actions
• monitor patients taking penicillin for an allergic reaction for at least 30 minutes after administration

• assess for penicillin allergy; may have a cross allergy
• give orally administered forms with food to decrease GI upset, even though this will delay absorption
• some of these drugs may cause disulfiram (antabuse) like reaction when taken with alcohol

• highly protein bound and will cause severe interactions with other protein bound drugs
• the absorption of oral erythromycin is enhanced when taken on an empty stomach, and because of the high incidence of GI upset, may drugs are taken after a meal or snack

• avoid milk products, iron preparations, antacids, and other dairy products because of the chelations and drug binding that occurs
• take all medications with 6 to 8 oz fluid
• because of photosensitivity avoid sunlight and tanning beds

• Adult: 4,500-10,000 microliters (mm^3)
• child: newborn : 9,000-30,000microliters (mm^3) , 2y/o: 6,000-17,000 microliters (mm^3) ; 10 y/o: 4,500 to 13,500 microliters (mm^3)

• Neutrophils (total): 50-70%; 2,500-7,000 microliters (mm^3)
• segments: 50-65%; 2,500-6,500 microliters (mm^3)
• bands: 0-5%; 0-500 microliters (mm^3)
• Eosinophils: 1-3%; 100-300 microliters (mm^3)
• Basophils: 0.4-1.0%; 40-100 microliters (mm^3)
• monocytes: 4-6%; 200-600 microliters (mm^3)
• lymphocytes: 25-35% 1,700-3,500 microliters (mm^3) ,