5 - Surgical Prophylaxis Flashcards
What is a surgical site infection?
Superficial or deep incisional or organ/space infection w/in 30 days of surgery or w/in 1 year of placement of prosthetic implant
What is important about surgical site infections?
- Increase hospital stay
- 5x re-admission
- 2-3x mortality
What are the most important patient-related risk factors for SSIs?
- Advanced age, obesity, malnutrition
- Hypoxia associated w/ smoking or COPD
- Diabetes, perioperative hyperglycemia
- Immunocompromised (especially HIV or HCV)
- Co-existing infection
- Colonization w/ resident organism
What are the most important surgery-related risk factors for SSIs?
- Infection control processes or sterilization and ventilation; equipment and technique
- Surgical wound classification
- Intraoperative thermoregulation, glucose control, O2 supplementation
- Placement of foreign material
- Duration and type of surgery
What is a clean surgical wound?
- No mucosal incision or entry to respiratory, GI, or GU tracts
- No inflammation/infection
- Primarily closure
What is a clean-contaminated surgical wound?
Mucosal incision or entry to respiratory, GI, GU tract w/o unusual contamination
What is a contaminated surgical wound?
- Acute wound/trauma
- Non-purulent inflammation
- Major break in sterile technique/ spillage
What is a dirty surgical wound?
- Chronic wound
- Perforated viscera
- Purulent inflammation/ infection
- Warrants antimicrobial therapy
What are the most common pathogens associated w/ SSIs?
- Staph aureus
- Streptococcus spp
- CoNS, most commonly staph epidermidis
- E. coli, Klebsiella, enterobacter, P. aeruginosa
When is E. coli most often associated w/ an SSI?
In urinary tract and gut surgeries
When is pseudomonas most often associated w/ an SSI?
Immunocompromised px previously on broad spectrum antibiotics
When is enterococcus most often associated w/ an SSI?
Immunocompromised pt w/ GI surgery (usually not pathogenic in wound infections unless the pt is immunocompromised)
What is the goal of antimicrobial prophylaxis for surgery?
- Reduce bacterial burden at incision site
- Prevent SSIs and associated pt morbidity, mortality, and healthcare costs
- Minimize collateral resistance (MRSA, ESBL, VRE)
- Avoid antimicrobial-associated adverse effects including C. difficile
What are the optimal characteristics for antimicrobial prophylaxis for surgery?
- Bactericidal w/ spectrum that covers most likely pathogens, but sufficiently narrow to minimize collateral resistance
- PK to provide adequate tissue concentrations for duration of surgery from incision to closure
- High safety profile
- Cost effective
What are some institutional initiatives that may improve delivery of optimal antimicrobial prophylaxis for surgery?
- Education
- Standardized guidelines for timing of preoperative dose w/in 1 h of incision, re-dosing during surgery as required and limiting duration
- Audits and reporting of performance, compliance and outcomes
Which antibiotics are the most commonly prescribed for surgical prophylaxis and why?
- Cephalosporins
- Broad spectrum, favourable PK profile, low adverse effects, and low cost
What are some generalizations that can be made about the antibiotics used for surgical prophylaxis?
- First gen cephalosporins (like cefazolin) are preferred choice (used when targeting skin microbes)
- Vanco is used for procedures involving implantation of a prosthetic device in which the rate of MRSA is high
- If MRSA risk is low and a beta-lactam allergy exists, clinda is used
What is important to remember during cardiac surgery?
- Pt is attached to a bypass machine so the heart isn’t beating, which drastically increases the Vd of the pt
- Should consider giving a higher dose, dosing more frequently, or using a continuous infusion
What are some disadvantages to vancomycin?
- Broadest gram pos, so generally reserve for when it is really needed
- Possibility of VRE or MRSA developing resistance
- Minimum infusion time is 1h if giving 1g or less
What is important to remember about aminoglycosides w/ respect to gram pos coverage?
Have gram pos coverage, but are never used alone; always used w/ another drug for synergy
What is the antimicrobial prophylaxis for a clean head and neck procedure w/ prosthesis placement?
- Cefazolin
- [Clindamycin +/- gentamicin] for allergy
What is the antimicrobial prophylaxis for a clean-contaminated head and neck procedure w/ mucosal incision?
- Cefazolin + metro for 24 h or less
- [Clindamycin + gentamicin} for allergy
For antimicrobial prophylaxis, what should be considered when a guideline says +/- gentamicin?
Consider if gram neg pathogens are a concern based on local SSI surveillance data
What is the antimicrobial prophylaxis for thoracic procedures (ex: lobectomy, pneumonectomy, lung resection)?
- Cefazolin
- [Clindamycin +/- gentamicin] or [Vancomycin +/- gentamicin] for allergy
What is the antimicrobial prophylaxis for open heart surgery?
- Cefazolin for at least 24-48 h
- [Vancomycin +/- gentamicin] for allergy
What is the antimicrobial prophylaxis for cardiac device insertion?
- Cefazolin
- [Vancomycin] for allergy
What is the antimicrobial prophylaxis for a clean gastroduodenal procedure for high risk (what is considered high risk)?
- High risk = cancer-related, obesity, decreased gastric acidity/ motility, obstruction, bleeding, perforation
- Cefazolin
- [Clindamycin + gentamicin] or [vancomycin + gentamicin]
What is the antimicrobial prophylaxis for a clean-contaminated gastroduodenal procedure w/ entry into GI tract?
- Cefazolin
- [Clindamycin + gentamicin] or [vancomycin + gentamicin]
What is the antimicrobial prophylaxis for a small intestinal procedure?
- Non-obstructed = cefazolin
- Obstructed = cefazolin + metro
- [Clindamycin + gentamicin] or [metro + gentamicin] for allergy of either obstructed or non
What is the antimicrobial prophylaxis for a large intestinal procedure
- Cefazolin + metro
- [Metro + gentamicin] for allergy
What is the antimicrobial prophylaxis for high risk biliary tract procedures (what is considered high risk)?
- High risk = emergency, acute cholecystitis, prior biliary surgery <1 m, stones, obstruction, prothesis, > 70 y/o, DM, pregnancy
- Cefazolin
- [Clindamycin + gentamicin] or [metro + gentamicin]
What is the antimicrobial prophylaxis for a caesarean delivery?
- Elective = cefazolin
- Emergency = cefazolin +/- azithromycin
- [Clinda + gent] for allergy
What is the antimicrobial prophylaxis for a hysterectomy?
- Cefazolin
- Cancer related = cefazolin + metro
- [Clinda + gent] or [metro + gent] for allergy
What is the antimicrobial prophylaxis for a hernioplasty (mesh) or herniorrhaphy (suture)?
- Cefazolin
- [Clinda or vanco] for allergy
What is the antimicrobial prophylaxis for a mastectomy (cancer-related) or other high risk?
- Cefazolin
- [Clinda or vanco] for allergy
What is the antimicrobial prophylaxis for a high risk lower urinary tract instrumentation or an upper urinary tract instrumentation?
- PO = ciprofloxacin or TMP-SMX
- IV = cefazolin or (gentamicin +/- clinda)
- No option for allergy
What is the antimicrobial prophylaxis for an open/ laparoscopic urinary tract procedure w/o entry into GU tract?
- Cefazolin (consider adding gent for prosthesis placement)
- [Clinda or vanco]
What is the antimicrobial prophylaxis for an open/ laparoscopic urinary tract procedure w/ entry into GU tract?
- Cefazolin +/- gent (consider adding gent for prosthesis placement and prostatectomy if prior antibiotics, hospitalization, biopsy-related infection, international travel)
- [Cipro] or [gent + clinda]
What is the antimicrobial prophylaxis for all vascular procedures?
- Cefazolin
- [Clinda +/- gent] or [vanco +/- gent]
What is the antimicrobial prophylaxis for orthopedic joint replacement, implantation, or fracture repair?
- Cefazolin +/- gent for maximum 24 h (to prevent bone infection; consider adding gent for type 3 open fractures)
- [Clinda +/- gent] or [vanco +/- gent]
What is the antimicrobial prophylaxis for orthopedic lower limb amputation?
- Cefazolin +/- metro for maximum 24 h
- [Clindamycin + gent] for allergy
What is the preoperative dose of cefazolin for antimicrobial prophylaxis? When is re-dosing required?
- 2g IV
- 3g IV for 120 kg and over
- Re-dose every 4 h
What is the preoperative dose of clindamycin for antimicrobial prophylaxis? When is re-dosing required?
- 900 mg IV
- Re-dose every 6 h
What is the preoperative dose of gentamicin for antimicrobial prophylaxis? When is re-dosing required?
- 3-5 mg/kg IV
- No re-dosing required b/c 5 mg/kg covers for at least 24 h
What is the preoperative dose of metronidazole for antimicrobial prophylaxis? When is re-dosing required?
- 500 mg IV
- No re-dosing
What is the preoperative dose of vancomycin for antimicrobial prophylaxis? When is re-dosing required?
- 15 mg/kg IV
- No re-dosing
What should be considered when re-dosing antimicrobial surgical prophylaxis?
- Re-dosing recommended if blood loss over 1500 mL or for prolonged procedures
- May not be required if prolonged t1/2 due to reduced renal function
