Table 4: International published guidelines.
+For open‐heart surgery only: use maximum cefazolin 2 gm; redose cefazolin when patient is removed from bypass; alternative to cefazolin monotherapy is cefazolin plus vancomycin for patients at high risk for MRSA. (Procedure involves insertion of prosthetic vaor vascular graft).
++Major reactions include anaphylaxis, hives, shortness of breath, wheezing, edema. For minor reactions (nausea, vomiting, diarrhea, mild rash, itching), cephalosporins may still be used.
+++High risk gastroduodenal: morbid obesity, esophageal obstruction, decreased gastric acidity or decreased gastrointestinal motility
*High risk biliary: acute cholecystitis, non‐functioning gall bladder, obstructive jaundice or common duct stones
**Colorectal procedures: Oral prophylaxis prior to surgery ‐ After appropriate diet and catharsis, 1 gram of neomycin plus 1 gram of er ythromycin at 1 pm, 2 pm, and 11 pm or 2 grams of neomycin plus 2 grams of metronidazole at 7 pm and 11pm the day before an 8 am day operation
***High risk genitourinary: urine culture positive or unavailable, preoperative catheter, transrectal prosthetic biopsy, placement of prosthetic material
##Vascular procedures: Clostridia can also be present in lower extremity amputation for ischemia [14-18].

Recommended intravenous antibiotics for surgical procedures	Common pathogens	Recommended antibiotic prophylaxis	Post operative duration
Cardiac Heart surgery+, PDA (patent ductus arteriosis), ASD/VSD (atrial/ ventricular septal defect), Glenn Shunt, valve replair/replacement, prosthetic graft ertion Aortic reconstructionins	S. epidermidis, S. aureus	Cefazolin OR Vancomycin for known MRSA or high risk for MRSA, or major reaction to beta‐lactams++	Discontinue within 48/72 hrs of surgical end time
Gastrointestinal esophageal, gastroduodenal PEG placement/ revision/ conversion to other feeding tubes OR high‐risk conditions Biliary, including lap cholecystectomy Colorectal** Appendectomy or ruptured viscus	Enteric gram‐negative bacilli, gram positive cocci Enteric gram‐negative bacilli, gram positivec occi, clostridia Enteric gram negative bacilli, anaerobes, enterococci	For high risk+++: Cefazolin If major reaction to beta‐lactams++: Clindamycin plus Gentamicin. For high risk*: Cefazolin If major reaction to beta‐lactam++:clindamycin plus Gentamicin Cefoxitin OR Ampicillin/sulbactam ORCefazolin plus Metronidazole If major reaction to beta‐lactams++: Clindamycin plus Gentamicin	Discontinue within 24 hrs of surgical end time
Head and Neck Surgery Incision through oral or pharyngeal mucosa, lower jaw fraction, removal of esophagus pouch	Anaerobes, enteric gramnegative bacilli, S.aureus	Cefazolin OR If major reaction to beta‐lactams++: Clindamycin plus Gentamicin	Discontinue within 24 hrs of surgical end time
Neurosurgery## Craniotomy, shunt placement/revision, insertion of pump/reservoir, spinal procedure (laminectomy, fusion or cord decompression)	S. aureus, S. epidermidis	Cefazolin OR Vancomycin for known MRSA or high risk for MRSA, or major reaction to beta‐lactams++	Discontinue within 24 hrs of surgical end time
Orthopedic Spinal procedures or implantation of hardware If tourniquet is used, give antibiotic before tourniquet inflation	S. epidermidis , S. aureus	Cefazolin or Cefepime and Vancomycin for known MRSA or high risk for MRSA, or major reaction to beta‐lactams++	Discontinue within 24 hrs of surgical end time
Thoracic Lung resection, VATS	S. aureus, S. epidermidis, streptococci, enteric gramnegative bacilli##	Cefazolin OR Vancomycin or Clindamycin for known MRSA or high risk for MRSA, or major reaction to beta‐lactams++	Discontinue within 24 hrs of surgical end time
Vascular (see Cardiac) Extremity amputation for ischemia, vascular access for hemodialysis	S. aureus, S. epidermidis, enteric gram-negative bacill	Cefazolin OR Vancomycin OR Clindamycin for known MRSA or high risk for MRSA, or major reaction to beta‐actams++	Discontinue within 24 hrs of surgical end time
Gynecologic	Enteric gram negative bacilli, anaerobes, Gp B strep, enterococci	Cefoxitin OR Ampicillin plus Metronidazole plus Gentamicin If major reaction to beta‐lactam++: Clindamycin plus Gentamicin	Discontinue within 24 hrs of surgical end time
Genitourinary Bladder augmentation, pyeloplasty	Enteric gramnegative bacilli, anaerobes, enterococci	For high risk only***: Cefazolin OR Cefoxitin OR Ampicillin plus Metronidazole plusGentamicin If major reaction to beta‐lactam++: Clindamycin plus Gentamicin	Discontinue within 24 hrs of surgical end time