Part 1-Antimicrobials Antiseptics, Disinfectants... Flashcards
10 main Risk factors for infection
Extremes of age (< 5 ; >65) Poor nutrition Obesity Diabetes mellitus Peri-op glycemic control PVD Use of tobacco Coexistent infections Altered immune response Corticosteroid therapy **
other Risk factors for infection
Surgical scrub/Hair Removal
Surgical experience of the surgeon (Inst. V.)
Technique (open vs lap) (Inst. V.)
Duration of procedure (Inst. V.)
Sterilization of instruments (Inst. V.)
Maintenance of periop normothermia (Inst. V.)
Inst. V. = Institutional Variables
what have studies shown in cardiothoracic surgery population that will reduce deep sternal infections by 50%
Glucose control
for cardiothoracic surgery what is given continuously to reduce surgical site infection compared to injections
continuous insulin infusion
what findings for bowel surgeries have shown a significantly lower number of surgical site infections
BS <200 for 48hrs
hypoglycemia issues is a concern if we keep the blood sugar too low increase what rate in these patients
mortality increases when compared to conventional treatment
Stopping smoking shows a 50% decrease in infection rates- how many weeks must cessation take place
4-8 weeks
what are the issues with having the patient stop smoking
we need to provide with resources to be successful
name the three negative consequences of hypothermia on infection and impaired healing
Results in peripheral vasoconstriction
Decreased wound oxygen tension
Decreased recruitment of leukocytes
when intraoperative warming is used what percent decrease in surgical site infections exist
64% decrease
there are few studies that support this claim - but what does immunosuppression from long term use of corticosteroids increase risk of
surgical site infection !
long term steroid use and bowel surgeries is associated with
anastomotic leaks
True or false
one time corticosteroid dose for n/v and pain does not promote infection
true
cefazolin adult dose
2g
cefazoline adult dose of 3 grams when weight is
greater or equal to 120kg
cefazolin redosing
q4
cefazolin half life
1.2-2.2
Ceftriaxone adult dose
2g
Ceftriaxone recommended redosing
na
Ceftriaxone half life
5.4-10.9
Cipro adult dose
400mg
cipro redosing schedule
na
cipro half life
3-7hrs
Clindamycin adult dose
900mg
clindamycin half life
2-4hrs
clindamycin redosing
q6hrs
gentamicin adult dose
5mg/kg
gentamicin redosing
na
gentamicin half lfie
2-3hrs
levofloxacin and metronidazole adult dose
500mg
levofloxacin and metronidazole redosing
na
half life levofloxacin and metronidazole
6-8hrs
vancomycin adult dose
15mg/kg
vancomycin redosing
na
vancomycin half life
4-8hrs
SCIP Inf 2
prophylactic antibiotics are discontinued within how many hours of surgery
24hrs
SCIP Inf 3
prophylactic antibiotics are discontinued with how many hours of cardiac surgery
48hrs
SCIP Inf 1
prophylactic abx are received within how many hours prior to surgical incision
1hr
SCIP Inf 4
cardiac surgery patients must have a blood sugar at 6 am less than or equal to
200
SCIP Inf 5
postoperative wound infection diagnosed during ??
index hospitalization (admission)
SCIP Inf 6
surgical patients must have “this” removed
appropriate hair
SCIP Inf 7
colorectal surgical patients with immediate postoperative “””
normothermia
if patient is receiving thyroidectomy or mastectomy- considered a clean elective surgical procedures- what do we consider about abx
risk vs benefits
what is the predominant organisms causing surgical site infection after clean procedure
skin flora Staphylococcus aureus and Staphylococcus epidermidis
In clean-contained procedures, such as abdominal procedures and solid organ transplantation, the most common organisms include:
Gram-negative rods
Enterococci
Staphylococcus aureus
Staphylococcus epidermidis
abx for uncomplicated appendicitis
cefoxitin, cefotetan, cefazolin, metronidazole
ophthalmic abx
neomycin-polymyxin and cefazolin
lower tract instrumentation with risk factors for infection abx
fluroquinolone
liver transplantation abx
piperacillin-tazobactam, cefotaxime +ampicillin
IgE-mediated anaphylactic reactions to antimicrobials S/S:
Occur 30-60 min after dosing Urticaria (Hives) Bronchospasm Hemodynamic collapse Life threatening emergency
patients with a documented IGE mediated anaphylactic reactions can be substituted with
clindamycin or vancomycin
what can be administered when MRSA is considered likely such as children or elderly
vancomycin
what else has been considered effective in eliminating MRSA colonization in children and adults
nasal application of mupirocin
US FDA has approved ““this” use to decolonize adults and healthcare works and recommends preoperative screening in high risk patients
nasal application of mupirocin
in the absence of documented or highly suspected colonization or infection with MRSA or known IGE medicated response to beta lactate antibiotics do we routinely prophylactically give vancomycin??
why??
no, due to the hemodynamic instability histamine release (red man syndrome)
Nursing home stay
Hemodialysis
OR
Known IgE mediated response to beta-lactam Abx
MRSA- vancomycin is considered less effective than ___drug
cefazolin
colorectal and abdominal surgeries
clean-contaminated procedures require additional coverage for what three patogens
gram-negative rods
anaerobes
skin flora
for clean contaminated procedures metronidazole can be added with
Cefazolin Cefoxitin Cefotetan Ampicillin-sulbactam, Ertapenem ceftriaxone
does bowel prep alone reduce infection
alone- no
what is used to decontaminate the digestive tract of gram negative organism, S aureus and yeast from oral cavity to rectum
oral topical polymyxin
tobramycin
amphotericin
what is the most frequent complication of prophylactic antimicrobials. This includes IV cephalosporins
pseudomembranous colitis
nephrotoxicity is associated with what three abx
aminoglycosides
polyxins
amophotericin B
neutropenia is associated with what three abx
penicillins
cephalsoporins
vancomycin
Leukopenia/Thrombocytopenia (folate deficiency)
trimethoprim
Seizures
penicillins and other beta lactams
metronidazole
neuromuscular blockade
aminoglycosides
all reactions
all antimicrobials but most often with B-lactam derivatives
benign intracranial HTN
tetracyclines
GI irritation
tetracyclines
prolonged QT interval
erythromycin
fluoroquinolones
hyperkalemia
trimethoprim-sulfamethoxazole
tendonitis
fluorquinolones
teratogenicity
tetracyclines metronidazole rifampin trimethoprim fluoroquinolones
Antimicrobial therapy is more likely to be effective if the infected material is removed such as
Foreign body
Prosthesis
Obstructing lesions
Such as pneumonia behind a blocked bronchus
Nearly 80% of nosocomial infections (NI) occur in 3 sites:
Urinary tract
Respiratory tract
Blood stream
NI highly associated with:
Ventilators
Vascular access catheters (most common cause of bacteremia or fungemia)
Urinary catheters
organism infecting access catheters most commonly comes from the colonized ___ or ___ and reflect skin flora such as
hub or lumen
s aureus
s epidermidis
what is the usual initial therapy of suspected intravascular catheter infection because of the high incidence of MRSA and MRSE in the nosocomial environment.
vancomycin
True/False
Most antimicrobials cross the placenta and enter maternal milk
True
the immature fetal liver may lack certain ____ to metabolize certain drugs
enzymes
are the pharmacokinetics and toxicities in fetus different form those of children and adults
yes
in early pregnancy- what is a concern when any drug is administered
teratogenicity
Increases in maternal blood volume, glomerular filtration rate, and hepatic metabolic activity may decrease plasma antimicrobial concentrations by what percent
10-50%
in some what is the effect of delayed gastric emptying as it relates to the PO absorption of antimicrobials
decreases absorption
name the three drugs considered safe in pregnancy
Penicillins
erythromycin base
cephalosporins
maternal toxicity and fetal toxicity for
Penicillins
erythromycin base
cephalosporins
maternal- allergic reactions
fetal- none
what drug in pregnancy do we avoid
metronidazole- allergic reactions, alcohol intolerance, peripheral neuropathy.
what drugs are contraindicated in pregnancy
erythromycin estolate
fluoroquinolone
tetracyclines
trimethoprim
what drugs in pregnancy do we use cautiously
aminoglycosides
clindamycin
rifampin
sulfonamides
what can alter PO absorption for the elderly
decreased gastric acidity and GI motility
what two drugs require adjustments in dosing regiments in the elderly
vancomycin and aminoglycosides
why is distribution, excretion, and metabolism altered in the elderly
metabolism=decrease hepatic blood flow
excretion=decreased GFR
distribution= increased total body fat, decreased plasma albumin concentrations
PCN and cephalosporins do not need significant changes in dosage schedule as long as “this” remains normal
creatinine concentrations
HIV patients have an increased risk of postoperative infections based on their increased risk for opportunistic infection. how do we mitigate this risk
good preoperative control on an antiretroviral regimen with preserved T4 cell counts
PCN is a dicyclic nucleus consisting of what two rings
thiazolidine ring
connected to
beta-lactam ring
PCN has a bactericidal action that reflects the ability to interfere with the synthesis of “this”, which is an essential component of cell walls of susceptible bacteria
peptidoglycan
PCN may be classified into sub grounds based on what 3 things
structure
spectrum of activity
beta-lactase susceptibility
PCN also decreases the availability of an inhibitor of “this” such that the uninhibited enzyme can then destroy (lyse) the structural integrity of bacterial cell walls.
murein hydrolase
Cell membranes of resistant gram-negative bacteria are in general resistant to PCN because they prevent access to sites where synthesis of peptidoglycan is taking place.
Cell membranes of resistant gram-negative bacteria are in general resistant to PCN because they prevent access to sites where synthesis of peptidoglycan is taking place.
