Exam 1 Antibiotics and Respiratory Flashcards
Goals and General Rules for Antibiotics
inhibit organisms at concentrations that are tolerated by the host
seriously ill/immunocompromised- bactericidal
narrow spectrum before broad spectrum or combination therapy to preserve normal flora
Why does anesthesia care about antimicrobals
timely administration
reimbursement for quality care
potential for adverse reactions
cross reactions with other medications we administer
Potential for adverse reactions with abx
hypersensitivity reaction (dose dependent)
direct organ toxicity (dose dependent)
potential for superinfections
identify patient at risk for complications
SSI are the ____ most common healthcare associated infection
second
SSI develop in ____ of 30 million surgical patients
2-5%
Represent approx. _____ of all hospital acquired infections annually in the US and cost ___ dollar/year
14-16%
1 billion
SSIs account for __ of surgical mortality and lead to
3%
increased readmissions
increased LOS
increased hospital costs
SSI defined
as an infection related to a operative procedure that occurs at or near the surgical incision within 30 days of the procedure
Additional details of SSI
purulent exudate draining from a surgical site
+ culture obtained form a surgical site that was closed initally
surgeon’s diagnosis of infection
surgical site that requires re-opening to at least one of the following signs or symptoms: tenderness, swelling , reddness, heat
Surgical Risks for Infection
procedure type
skill of surgeon
use of foreign material or implantable device
degree of tissue trauma
Patient Risks for SSI
diabetes smoking obesity malnutrition systemic steroid use immunosuppressive therapy intraop hypothermia trauma prosthetic heart valves
Anesthesia providers use of antibiotics can decrease infection with
timely and appropriate use of antibiotics
maintenance of normothermia
proper syringe/med administration practices
SSI Prevention Antibiotic Timing
antibiotic prophylaxis 1 hour before incision
30-60 min before incision is the ideal window for drug administration
hypothermia is associated with
increased Blood loss, increased transfusions requirement prolonged PACU stay impaired immue dysfunction compromised neutrophil function leads to vasoconstriction tissue hypoxia and increased SSI
SBE Prophylaxis
amoxicillin 2gm PO
IV ampicillin 2 gm IV
Pencillin Allergy: Ceftriaxone 1gm IV
cefazolin 1gm IV (not in patients with hypersensitivity to PCN)
ceftazolin, cefuroxime or vancomycin
if B lactam allergy, vancomycin or clindamycin
cardiothoracic and vascular surgery
Cefetan, cefazolin, cefoxitin, cefuroxime, ampillicin/bactrim
B lactam allergy: clinda + gent or cipro or met +gent or clindamycin monotherapy
hysterectomy
Cefazolin or cefuroxime
B lactam- vancomycin or clindamycin
hip or knee anthroplasty
Cefotetan, cefoxitin + met or amp/sulbactam
Colon
Bactericidal antibiotics
kill the susceptible bacteria
bacteriostatic antibiotics
reversibly inhibit the growth of bacteria
duration of therapy must be sufficient to allow cellular and humoral defense mechanism to eradicate the bacteria
Bactericidal Antibiotics
pencillins & cephalosporins isoniazid metronidazole polymyxins rifampin vancomycin aminoglycosides quinolones
Bacteriostatic Antibiotics
chloramphenicol clindamycin macroslides sulfonamides tetracyclines trimepthoprim
Structure and Organism of Pencillin
basic structure of dicyclic nucleus with thiazolidine ring connected to B-lactam ring Bactericidal pneumococcal meningococcal streptococcal actinomycosis
MOA of Pencillin
interacts with synthesis of peptidoglycan which is essential to component of cell walls of susceptible bacteria
Excretion of Pencillin
renal excreted rapidly, plasma concentration decrease 50% in first hour
10% glomerular filtration/90% renal tubular secretion
anuria increases elimination half time by 1/2fold
DOA of Pencillin
administration of probenecid will reduce renal excretion and prolong action
Adverse Reactions of Penicillin
hypersensitivity most allergenic of antimicrobals rash/fever hemolytic anemia maculopapular rash
What drugs is common with cross senisitivity with pencillin?
3% B-lactam ring
Penicillin Uses
otitis media meningitis sore throat pneumonia & respiratory infections septicemia gonorrhea/UTIs
Organisms treated by Second Gen Penicillin
pneumoncoccal meningococcal streptococcal actinomycosis wider range of activity (gram - H. influenza and Ecoli
Second Generation Penicillins Examples
amoxicillin
ampicillin
Cefazolin
bactericidal antimicrobals that inhibtit bacterial cell wall synthesis and have low toxicity
broad spectrum activity
low allergy incidence (1-10%)
anaphylaxis is 0.02% (due to B lactam ring)
cross sensitivity with other Cephalosporins
RENALLY EXCRETED
Generations of Cephalosporins
Start with stronger GRam + coverage then increase Gram - coverage as increase class
Macrolides Examples
Erythromycin and Azithromycin
Macrolides
compounds characterized by a macrolytic lactone ring containing 14-16 atoms with a deoxy sugar attached
Erythromycin protype
Macrolides are effective against
gram + bacilli, pneumococci, streptococci, staphylococci, mycoplasma and chlamydia
Erythromycin
bacteriostatic or bactericidal depending on dose
Metabolism of Erythromycin
CYP 450 system and thus increase concentration of theophylline, warfin, cyclosporin, methylpredinisone and digoxin
Excretion of Erythromycin
bile
