Pharmacology 3 Flashcards
The premise of antibiotics prior to a dental procedure is to prevent what 2 things?
Infective endocarditis
Prosthetic joint infections
T/F
There is NO scientific evidence that supports antibiotic prophylaxis defends against IE (infective endocarditis) and Prosthetic Joint Infections.
True
The introduction of bacteria in the bloodstream is called?
Bacteremia
T/F
Bacteremia is linked to IE (infective endocarditis) and PJI (prosthetic joint infections).
False
What are the 2 pathogen species responsible for IE and PJI?
viridans Streptococci
Staph aureus
There is a _____ fold increase in pts with prosthetic valves and previous history of Endocarditis for IE.
400
T/F
Rheumatic valvular disease, cyanotic congenital heart disease, and degenerative valve lesions are also at risk for Infective Endocarditis
True
What are the 4 conditions that require prosthetic antibiotics in a dental setting?
Prosthetic cardiac valve
Previous history of Infective Endocarditis
Congenital heart disease
Cardiac Transplantation
How long after a Congenital Heart Defect is repaired must prosthetic antibiotics be administered?
First 6 months
Congenital heart disease will be given if there is _____ cyanotic CHD, including _____ shunts and conduits.
Unrepaired
Palliative
*means vessels swapped, defective valves, vessels
T/F
Severe cases of Great Artery transposition can be fatal, and are associated with many conditions later in life, including leaky heart valves, arrhythmias, declining function, etc.
True
T/F Blue babies (transposition of great arteries) require lifelong follow-ups with a cardiologist
True
The AHA recommends that any repaired CHD with _________ at the site / adjacent to the site should be given prosthetic antibiotics
Residual Defects
Cardiac transplantation may develop cardiac ________, which is why antibiotic prophylaxis is recommended.
vavulopathy
T/F
A Cardiac shunt (congenital) is the same as an Arteriovenous Shunt
False
*bypass with tubing, limited life-span
T/F
Within the 1st 5 minutes of a dental procedure, you get bacteremia
True
- 79% placebo
- 56% amoxicillin
- 28% toothbrushing
Bacteremia after dental procedures is usually less than 20 minutes, what % of the extraction/placebo group had an IE related species after 60 minutes?
% toothbrushing group?
% extraction/amoxicillin?
5%
2%
0%
Viridans strept were found in ____% in brushing group
____% extraction/amoxicillin
____% extraction/placebo
48%
49%
70%
T/F
Amoxicillin significantly reduces viridans Strept.
True
Why is antibiotic prophylaxis so contentious with joint replacements?
Infection 2nd common cause failure
*aseptic loosening primary
T/F
Prior joint surgery, failure antimicrobial prophylaxis during surgery, immunosuppression, history, high ASA score are factors with higher risk of Prosthetic Joint Infection
True
________ is a risk factor for hematogenous prosthetic joint infection, especially with _________ (bacteria).
Bacteremia
Staph aureus
T/F
Chewing causes transient bacteremia in 40% of episodes
True
____ are rarely implicated in bacteremia
_____-group Streptococci constitute most facultative oral flora and are the ________ cause of transient bacteremia.
Staph
Viridans
Most common
Viridans Streptococci acount for ____% of all hematogenous prosthetic joint infections.
2%
Prolonged, high-grade bacteremia is associated with PJI, and after dental procedures bacteria are at _____ levels needed to seed prosthesis (animal studies)
much lower levels
basically, dental procedures couldn’t cause
The cumulative exposure to transient bacteria due to chewing, brushing, etc, is Higher/Lower than following single exposure during dental procedure.
Several times Higher
T/F
According to 1 study, PJI from a dental source occured after 0.2% knees and 6% hip replacements
True
*other studies counter claim
T/F
According to Mayo study, neither low-risk nor high-risk dental procedures were associated with an increased risk of prosthetic knee or hip infection
T/F
Antibiotic premedication was not associated with lower risk.
True
True
According to the Mayo study, what may decrease bacteremia from daily activities?
Good oral hygiene
Cultures from infected joints are most often ______, according to Mayo study
What species are associated with dental procedures?
Staph
viridans Strept, beta hemolytic strept, G+ anaerobes
The 2003 study recommended prophylaxis for 2 years, and asked to consider premed all the time in immunocompromised pts and pts with previous prosthetic joint infections, malnourishment, hemophilia, HIV, Type I diabetes, and malignancy.
True
Why do orthopedic surgeons prefer cephalosporins to amoxicillin?
Cephalosporins enter synovial fluid
*Amoxicillin still ok though
High risk and low risk dental procedures _____ factors for joint infections for at-risk subgroups
Not Risk
Bottom line: in 3 of 4 case studies no association was demonstrated between dental procedures and PJI, therefore…
No need to treat prophylactically
*moderate certainty of no association
Antibiotic Stewardship (overprescribing) is a major factor in NOT prophylactically prescribing.
True
Postoperative UTI and Wound drainage/hematoma after arthroplasty (and a host of other conditions) ARE risk factors for PJI independent of Dental Procedures
True
T/F
In general, pts with prosthetic joint implants are NOT recommended to have prophylactic antibiotics
True
What are 2 other conditions that may require prophylactic antibiotics?
Penile implants
hx drug abuse and valve damage
Is there premed recommended for stents?
No
What 3 methods of dialysis would require premed?
What 1 method doesn’t?
A/V shunts, tunneled catheter, periotoneal port
fistula access
T/F
Picc line, Hickman catheter, Portacath, and CSF shunts don’t require premed
False
What are 4 conditions that don’t have premed guidelines?
Fen-Phen hx
Decreased WBC from chemo/immunosuppressive therapy
Organ Transplant
IV drub abus hx
Prophylaxis is indicated when _____ is likely.
Bleeding
If there is ______ bleeding, antibiotics are given immediately.
Unanticipated
If a sequence of procedures is needed, a ________ day interval is recommended to minimize resistance.
9-14
Premed is recommended in which dental procedures?
All involving manipulation of gingival tissue, perforation, or periapical region of teeth.
T/F
Acute infections at distant sites (like oral cavity) increase risk of infection in PJI.
True
*includes perio infection
How do most devices cause infection?
Contamination time of insertion
T/F
If no complications after 2 years, premed is not indicated
True
*as well as pins, plates, screws, breast, dental, and corneal implants
T/F
Complications following initial placement, recurrent pain, and history of previous joint replacement failures put one at high risk for joint infections.
True
2014 task force High Risk pts identified with Prior Operation on Joint, Diabetes, Immunocompromised, and what 2 other major factors?
Wound draingage/hematoma after arthroplasy/or post op infection
Post-op UTI
If not allergic to Penicillin, what is the premed regimen for pts with prosthetic implants?
(3 possibles)
Cephalexin (Keflex) 2 gm orally 1 hr prior
Cephradine (Velosef)
Amoxicillin (Amoxis, Trimox)
If not allergic to Penicillin, but unable to take oral meds, what is the premed regimen for pts with prosthetic implants?
(2 possibles)
Cefazolin (Ancef) 1 gm IM or IV 1 hr prior
Ampicillin 2 gm IM or IV 1 hr prior
If allergic to Penicillin, what is the premed regimen for pts with prosthetic implants?
Clindamycin (Cleosin) 600 mg oral 1 hr prior
If allergic to Penicillin and unable to take oral meds, what is the premed regimen for pts with prosthetic implants?
Clindamycin (Cleosin) 600 mg IV 1 hr prior
What is standard general prophylaxis for Adults?
Children?
Amoxicillin
Adults: 2 gm oral 1 hr prior
Children: 50 mg/kg oral 1 hr prior
What is standard general prophylaxis for Adults/children if unable to take oral meds?
Ampicillin
Adults: 2 gm IM or IV 30 min prior
Children: 50 mg/kg IM or IV within 30 min
If allergic to Penicillin, what are 4 options for general prophylaxis?
Clindamycin (Cleocin) A: 600mg 1hr prior C: 20 mg/kg 1 hr prior
Cephalexin (Keflex) A: 2 gm oral 1 hr prior C: 50 mg/kg 1 hr prior
Azithromycin (Zithromax) A: 500 mg oral 1 hr prior C: 15 mg/kg oral 1 hr prior
Clarithromycin (Biaxin) (same as azithromycin)
Pediatric dose =
(weight of child/150) x adult dose
If allergy to Penicillin is mild or in the distant past, what should replace?
If allergy was full blown Type 1 hypersensitivity?
Cephalosporin (6-8% chance allergic)
Clindamycin (azithromycin/clarithromycin secondarily)
*20% chance cephalosporin allergy w/ type 1
If already taking tetracycline, what would be a good premed?
Macrolides: azithromycin and clarithromycin
*must be static
***wouldn’t use clindamycin b/c premed dose cidal
T/F
If pt already on an antibiotic, a premed should come from a different class.
True
If allergic to Penicillin and unable to take oral meds, name 3 options for General Prophylaxis:
clindamycin: A: 600 mg IV w/in 30 min C: 20 mg/kg IV w/in 30 min
cefazolin (Ancef/Kefzol/Zolicef) A: 1 gm IM/IV w/in 30 min C: 50 mg/kn IM/IV w/in 30 min
ceftriaxone (Rocephin) A: 1 gm IM/IV w/in 30 min C: 50 mg/kg IM/IV w/in 30 min
Premed regimen for pts with Total Joint Replacement if not allergic to Penicilin:
Cephalexin (Keflex) or Cephradine (Velosef)
2 gm orally 1 hr prior
(Amoxicillin, general, is acceptable)
Premed regimen for pts with Total Joint Replacement if not allergic to penicillin but unable to take oral meds:
Cefazolin (Ancef) 1 gm IM/IV 1 hr prior
(Ampicillin 2 gm IM/IV 1 hr prior acceptable) `
Premed regimen for pts with Total Joint Replacement if allergic to penicillin
Clindamycin (Cleosin) 600 mg oral 1 hr prior
Premed regimen for pts with Total Joint Replacement if allergic to penicillin and unable to take oral meds:
Clindamycin (Cleosin) 600 mg IV 1 hr prior
