Surgical Prophylaxis:  Antimicrobial use

• Overview --Choice of agents (principles)

  • Need not eradicate every potential pathogen

  • Effective agent example -- cefazolin (Ancef, Defzol)

    • Long serum half-life

  •  Methicillin (Staphcillin)-resistant Staphylococcus aureus or methicillin (Staphcillin)-resistant coagulase-negative staphylococci -- vancomycin (Vancocin)

    •  routine use of vancomycin (Vancocin) for prophylaxis-- discouraged since it promotes vancomycin (Vancocin)-resistant strains

  • Colorectal surgery & appendectomy: cefoxitin (Mefoxin) or cefotetan (Cefotan) preferred due to enhanced activity relative to cefazolin (Ancef, Defzol) against anaerobes (bowel), e.g. Bacteriodes fragilis

  •  Agents not recommended

    •  Third-generation cephalosporins (cefotaxime (Claforan), ceftriaxone (Rocephin), cefoperazone (Cefobid), ceftazidime (Fortax, Taxidime, Tazicef), or ceftizoxime (Cefizox)

    •  Fourth-generation cephalosporins: e.g. cefepime (Maxipime)

    •  Rationale:

      •   Expense, some are less activin cefazolin (Ancef, Defzol) (against staphylococci)

      •   Non-optimal spectrum of action (includes activity against organisms not commonly encountered in elected surgery

      •   Wdespread for prophylaxis encourages emergence of resistance

•  Cardiac Surgery

  •  Prosthetic valve, coronary bypass, other open-heart procedures, pacemaker/defibrillator implantation

    •  Probable pathogen: -- Staphylococcus epidermidis, Staphylococcus aureus,Corynebacterium, enteric gram-negative bacilli

    •  Antibacterial drug:

      •  cefazolin (Ancef, Defzol), cefuroxime (Zinacef, Ceftin)-- IV

      • Vancomycin, IV(Vancocin) (if above agents are ineffective or contraindicated)

    •  Antibacterial drug pre-treatment reduces infection incidence after cardiac surgery;

      • Significant reduction in the infection incidence associated with permanent pacemaker implantation

•  Gastrointestinal diseases

  •  Esophageal/gastroduodenal

    • Probable pathogens:enteric gram-negative bacilli, gram-positive cocci

    • Treatment (high-risk only, i.e. esophageal obstruction, decreased gastric acidity/gastrointestinal motility, morbid obesity)

      • cefazolin (Ancef, Defzol) (IV)

  •  Biliary tract

    • Probable pathogens: enteric gram-negative bacilli, enterococci, clostridia

    • Treatment (high-risk only,i.e. age > 70, acute cholecystitis, non-functioning gallbladder, obstructive jaundice or common duct stones)

      • Cefazolin (Ancef, Defzol) (IV)

  •  Colorectal

    • Probable pathogens: enteric gram-negative bacilli, anaerobes, enterococci

    • Treatment:

      • Oral --neomycin + erythromycin base

      • Parenteral -- cefoxitin (Mefoxin) or cefotetan (Cefotan) Or

      • Parenteral-- cefazolin (Ancef, Defzol) + metronidazole (Flagyl)

  •  Appendectomy, non-perforated

    •  Probable pathogens: enteric gram-negative bacilli, anaerobes, enterococci

    •  Treatment: cefoxitin (Mefoxin) Lorcet (hydrocodone/acetaminophen) fatigue and (IV)

  • Antibiotic prophylaxis:

    •   recommended for esophageal surgery with obstruction -- obstruction increases infection risk

    •  factors that promote high infection risk after gastroduodenal surgery:

      •   Reduced gastric acidity and gastrointestinal motility -- reduction may occur because of:

        • Obstruction

        • Hemorrhage

        • Gastric ulcer

        • Malignancy

        • Treatment with H₂ blocker {ranitidine (Zantac)} or proton pump, inhibitors {e.g. omeprazole (Prilosec)}

        • Morbid obesity

  •  Antibiotic prophylaxis not indicated for:

    •  Routine gastroesophageal endoscopy (may be used for high-risk patients undergoing esophageal dilatation or sclerotherapy of varicies)

• Gynecologic & Obstetric

  •  Vaginal or abdominal hysterectomy

    •  Probable pathogens: Enteric gram-negatives, anaerobes, enterococci, Group B strep

    •  Treatment: cefazolin (Ancef, Defzol) or cefotetan (Cefotan) or cefoxitin (Mefoxin)(IV)

  •  Cesarean section

    •  Probable pathogens: Enteric gram-negatives, anaerobes, enterococci, Group B strep

    •  Treatment: high-risk {active labor or premature membrane rupture};cefazolin (Ancef, Defzol) -- IV after cord clamping

  •  Abortion

    •  Probable pathogens: Enteric gram-negatives, anaerobes, enterococci, Group B strep

    •  Treatment: first trimester, high-risk {patients with previous pelvic inflammatory disease, previous gonorrhea or multiple sex partners) -- aqueous penicillin V (Pen-Vee K, Veetids) or doxycycline (Vibramycin, Doryx)

  •  Antibacterial prophylaxis:

    •  reduces infection incidence following vaginal hysterectomy & abdominal hysterectomy (probably)

    •  Perioperative/preoperative antibiotics: prevention of infection when given:

      •  following cord clamping in emergency cesarean section

      • high-risk situations {active Labor, premature membrane rupture,after mid-trimester abortion}

        • Possibly substantial protective effect of perioperative antibiotics in all women undergoing therapeutic abortions

• Genitourinary

  •  Probable pathogens: enteric gram-negative bacilli, enterococci

  •  Treatment: high-risk only (urinate culture positive/unavailable; preoperative catheter, transrectal prostatic biopsy) --ciprofloxacin (Cipro) {PO or IV}

• Head & Neck Surgery

  •  Incision through oral/pharyngeal mucosa.

  • Probable pathogens: Anaerobes, enteric gram-negative bacilli, Staphylococcus aureus

  • Treatment: clindamycin (Cleocin) + gentamicin (Garamycin)

    • reduce the high incidence of wound infection following head/neck operations which utilize incisions through oral or pharyngeal mucosal

• Neurosurgery

  •  Craniotomy

  •  Probable pathogens: Staphylococcus aureus, Staphylococcus epidermidis

  •  Treatment: cefazolin (Ancef, Defzol) or vancomycin (Vancocin) (IV)

  • Antibacterial prophylaxis

    •  Cerebrospinal fluid shunt: conflicting research results

    •  Craniotomy: antistaphylococcal antibiotic -- reduced infection incidence

    •  Spinal surgery: antibiotics not effective in reducing the already low postoperative infection rate following conventional lumbar discectomy.

    •  Questionable effectiveness (not yet demonstrated in controlled clinical trials) for spinal fusion, prolonged spine surgery, or insertion of foreign material

• Ophthalmic

  •  Probable pathogens: Staphylococcus epidermidis, Staphylococcus aureus, streptococci, enteric gram-negative bacilli, Pseudomonas

  •  Treatment: gentamicin (Garamycin), tobramycin (Nebcin), ciprofloxacin (Cipro), ofloxacin (Floxin), or neomycin-gramicidin-polymixin B; cefazolin (Ancef, Defzol)

  •  Most ophthalmologist use antibiotic eyedrops for prophylaxis in view of the potential for extremely serious postoperative endophthalmitis.{limited data to support effectiveness of prophylactic antimicrobials}

    • No evidence for the rational basis for use of prophylactic antibiotics when procedures do not invade the globe

• Orthopedic

  •  Total joint replacement, internal fracture fixation

  •  Probable pathogens: Staphylococcus aureus, Staphylococcus epidermidis

  •  Treatment: cefazolin (Ancef, Defzol) or vancomycin (Vancocin) (IV)

  •  Rationale for Prophylaxis:

    •  Antistaphylococcal agents decrease incidence of early & late infection following joint replacement

    •  Decrease infection rate in compound/open fractures and when hip & other fractures are managed with internal fixation using nails, plates, screws, or wires

    •  For diagnostic & operative arthroscopic surgery -- antibody prophylaxis is not justified

• Thoracic (noncardiac)

  •  Probable pathogens: Staphylococcus aureus, Staphylococcus epidermidis, streptococci, enteric gram-negative bacilli

  •  Treatment: cefazolin (Ancef, Defzol) or cefuroxime (Zinacef, Ceftin) or vancomycin (Vancocin)

  •  Rationale for Prophylaxis:

    •  Commonly used for routine pulmonary surgery; limited research support

    •  Insertion of chest tubes following closed-tube thoracostomy following chest trauma: cephalosporin (multiple doses) can prevent infection

    •  Single preoperative cefazolin (Ancef, Defzol) dose (pulmonary resection): decrease in the incidence of wound infection -- no decrease in incidence of pneumonia or empyema

• Vascular

  •  Arterial surgery (involving: a prosthesis, abdominal aorta, or groin incision)

    • Probable pathogen: Staphylococcus aureus, Staphylococcus epidermidis, enteric gram-negative bacilli

    • Treatment: cefazolin (Ancef, Defzol) or vancomycin (Vancocin)

  •  A lower extremity amputation for ischemia

    • Probable pathogen: Staphylococcus aureus, Staphylococcus epidermidis, enteric gram-negative bacilli, clostridia

    • Treatment: cefazolin (Ancef, Defzol)--or cefoxitin (Mefoxin) for better anaerobic coverage--or vancomycin (Vancocin)

  •  Rationale for prophylaxis:

    •  Cephalosporin: reduced likelihood of postoperative infection incidences following arterial reconstructive surgery on the abdominal aorta, vascular limb operations involving groin incisions, and lower extremity amputation for ischemia

    •  Recommended: for any vascular prosthetic material implantation (e.g. grafts supporting hemodialysis)

    •  Not indicated: carotid endarterectomy or brachial artery repair (assuming no prosthetic material involved)

The Medical Letter on Drugs and Therapeutics, "Antimicrobial Prophylaxis in Surgery", vol. 41 (issue 1060), August 27, 1999