CHEMOPROPHYLAXIS : SURGICAL

Objectives

The goal of antimicrobial prophylaxis is to prevent surgical site infection by reducing the burden of microorganisms at the surgical site during the operative procedure.

Single-dose prophylaxis is usually sufficient. If antimicrobial prophylaxis is continued post-operatively, the duration should be less than 24 hours (up to 48 hours for cardiac surgery), regardless of the presence of intravascular catheters or indwelling drains.

If the presence of pre-existing infections (known or suspected), use an appropriate treatment regimen instead of a prophylactic regimen for the procedure. However, re-dosing is required just prior to skin incision.

The optimal time for administration of pre-operative antibiotics is 60 minutes prior to surgical incision. Some agents, such as fluoroquinolones and Vancomycin, require administration over one to two hours; therefore, the administration of these agents should begin within 120 minutes before surgical incision.

An additional dose of prophylactic antibiotic during operation is indicated if:

Excessive blood loss (>1500ml)
Procedures exceed two half-life of the drug
If there are other factors that may shorten the half-life of the prophylactic agent (e.g. extensive burns)

Antimicrobial	Recommended Re-dosing Interval in Adults with Normal Renal Function (From Initiation of Preoperative Dose in hours)
Cefazolin	4
Cefuroxime	4
Ampicillin-sulbactam	2
Metronidazole	4
Clindamycin	6
Vancomycin	NA
Gentamicin	NA
Amoxicillin-clavulanate	3
Benzylpenicillin	2

For patients with Penicillin allergy, Clindamycin or Vancomycin is recommended unless stated otherwise. The dose of Vancomycin is according to patient’s body weight, as follows:

<75 kg: 1 gm infused over 60 minutes.
≥75 kg: 1.5 gm infused over 90 minutes.

Administration of Cefazolin in obese patients:

2 gm if body weight <120 kg.
3 gm if body weight ≥120 kg.

Obstetrics and Gynecology Surgery

Infection/Condition and Likely Organism	Suggested Treatment		Comments
Infection/Condition and Likely Organism	Preferred	Alternative	Comments
Cesarean Section Elective Emergency	Cefazolin 2gm IV ( 3gm IV for patients weighing ≥120 kg)	Ampicillin-sulbactam 3gm IV
Elective surgery: TAH/BSO Hysterectomy (vaginal or abdominal) Laparoscopy (vaginal and/ or uterus entered)	Cefazolin 2gm IV (3 gm IV for patients weighing ≥120 kg) OR Cefuroxime 750mg IV PLUS Metronidazole 500mg IV	Ampicillin-sulbactam 3gm IV	Consider second or additional dose for prolonged procedures.
Laparoscopic surgery (vagina and/or uterus not entered)	Antibiotic not recommended	Antibiotic not recommended
Repair of perineal tear e.g. third or fourth degree tears	Cefazolin 2gm IV (3 gm IV for patients weighing ≥120 kg) PLUS Metronidazole 500mg IV	Ampicillin-sulbactam 3gm IV	Duration: 5-7 days.
Surgical termination of pregnancy	Doxycycline 400mg PO as a single dose (1 hour prior to procedure) OR Azithromycin 1gm PO (1 hour prior to procedure)		No evidence outcomes are improved by including Metronidazole in prophylactic regimens.
Emergency laparotomy	As per elective surgery

Otorhinolaryngologic Surgery

Infection/Condition and Likely Organism	Suggested Treatment
Infection/Condition and Likely Organism	Preferred	Alternative
Head and Neck
Clean	Antibiotic not required	Antibiotic not required
Clean with placement of prosthesis (excludes tympanostomy tubes)	Cefazolin 2gm IV (3gm IV for patients weighing ≥ 120 kg)
Clean-contaminated cancer surgery Other clean-contaminated procedures with the exception of tonsillectomy and functional endoscopic sinus procedures	Cefazolin 2gm IV (3gm IV for patients weighing ≥ 120 kg) PLUS Metronidazole 500mg IV	Cefuroxime 1.5gm IV PLUS Metronidazole 500mg IV OR Ampicillin-sulbactam 3gm IV

Oral / Dental Surgery

Infection/Condition and Likely Organism	Suggested Treatment		Comments
Infection/Condition and Likely Organism	Preferred	Alternative	Comments
Clean Surgery (Class 1) Submandibular gland surgery Temporomandibular Joint (TMJ) Surgery Excision of benign tumors / cysts	Not indicated for most surgeries May be indicated if the duration of the surgery is expected to be very long For open reduction and internal fixation of facial bone fractures		Prophylaxis is recommended for all patients with an increased risk of surgical wound infection- i.e. in immunocompromised patients. *In patients with cardiac conditions with increased risk of Infective endocarditis.
Minor Clean-contaminated surgery (Class 2) Soft tissue surgery Dentoalveolar surgery*
Periodontal surgery			Chemoprophylaxis is indicated. Please refer to Chemoprophylaxis Non-Surgical Section – Infective endocarditis.
Minor clean-contaminated surgery (Class 2) Insertion of dental implants and use of graft material High degree of difficulty / long duration	Amoxicillin 1gm PO OR Clindamycin 600-900mg PO/IV OR Benzylpenicillin 2 MU IV	Amoxicillin-clavulanate 1.25gm PO or 1.2gm IV OR Cefuroxime 500mg PO or 1.5gm IV
Major clean-contaminated surgery (Class 3) Orthognathic surgery Excision / enucleation of large benign tumors / cysts All oral cancer surgery Open reduction and internal fixation of facial bone fractures	Benzylpenicillin 2MU IV OR Clindamycin 600-900mg IV	Amoxicillin-clavulanate 1.2gm IV OR Cefuroxime 1.5gm IV	For oral and maxillofacial fractures, antibiotic is recommended for the immediate post-trauma period and should be discontinued once open reduction and internal fixation is completed.

Plastic Surgery

Infection/Condition and Likely Organism	Suggested Treatment		Comments
	Preferred	Alternative
Not indicated: for the majority of clean procedures*, unless the patient has risk factors for postoperative infection (e.g. implantation of prosthetic material, prior skin irradiation). The continuation of antibiotics while waiting for non-infected skin grafts or flaps to epithelialize is not evidence-based.
For clean-contaminated procedures	Cefazolin 2mg IV (3gm IV for patients weighing ≥120 kg)	Amoxicillin-clavulanate 1.2gm IV

Vascular Surgery

Infection/Condition and Likely Organism	Suggested Treatment		Comments
Infection/Condition and Likely Organism	Preferred	Alternative	Comments
Amputation of ischemic limb	Ampicillin-sulbactam 3gm IV	Amoxicillin-clavulanate 1.2gm IV
Suspected organism: Staphylococcus spp. and anaerobic organism
Open and endovascular repair of abdominal aneurysm	Amoxicillin-clavulanate 1.2gm IV	Penicillin allergy: Vancomycin 1gm IV (1.5gm IV for patients weighing ≥75 kg)
Bypass surgery	Amoxicillin-clavulanate 1.2gm IV	Penicillin allergy: Vancomycin 1gm IV (1.5gm IV for patients weighing ≥75 kg)
Arteriovenous graft	Amoxicillin-clavulanate 1.2gm IV If high risk For MRSA: Vancomycin 1gm IV (1.5gm IV for patients weighing ≥75 kg)		MRSA risk (defined as history of MRSA colonization or infection, or inpatient of high-risk hospital or unit (where MRSA is endemic).

General Surgery

Infection/Condition and Likely Organism	Suggested Treatment		Comments
Infection/Condition and Likely Organism	Preferred	Alternative	Comments
Procedures involving entry into lumen of gastrointestinal tract (bariatric, pancreaticoduodenectomy)	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Cefuroxime 1.5gm IV
Other GI Procedures without entry into gastrointestinal tract (antireflux, highly selective vagotomy) - for high-risk patients	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Cefuroxime 1.5gm IV
Appendectomy for uncomplicated appendicitis Colorectal	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg) PLUS Metronidazole 500mg IV OR Ampicillin-sulbactam 3gm IV	Cefuroxime 1.5gm IV PLUS Metronidazole 500mg IV Penicillin allergy: Clindamycin 600-900mg IV PLUS Gentamicin 5mg/kg IV
Small intestine	Non-obstructed: Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Cefuroxime 1.5gm IV Penicillin allergy: Clindamycin 600-900mg IV PLUS Gentamicin 5mg/kg IV
Small intestine	Obstructed: Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg) PLUS Metronidazole 500mg IV	Cefuroxime 1.5gm IV PLUS Metronidazole 500mg IV Penicillin allergy: Clindamycin 600-900mg IV PLUS Gentamicin 5mg/kg
Hernia repair with mesh	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Amoxicillin-clavulanate 1.2gm IV OR Ampicillin-sulbactam 3gm IV	Includes laparoscopic repair Single / stat dose only.
Breast cancer surgery	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Amoxicillin-clavulanate 1.2gm IV OR Ampicillin-sulbactam 3gm IV	The benefits of routine postoperative antibiotic doses in reconstruction surgery are uncertain; there may be a benefit in obese patients or those treated with radiation therapy. The need for postoperative doses should be considered on an individual patient basis; if used, postoperative prophylaxis should not exceed 24 hours.
Breast reshaping procedures	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Amoxicillin-clavulanate 1.2gm IV OR Ampicillin-sulbactam 3gm IV
Breast surgery with implant (reconstructive or aesthetic)	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Amoxicillin-clavulanate 1.2gm IV OR Ampicillin-sulbactam 3gm IV

Orthopaedic Surgery

Infection/Condition and Likely Organism	Suggested Treatment		Comments
Infection/Condition and Likely Organism	Preferred	Alternative	Comments
Clean operations involving hand, knee, or foot and not involving implantation of foreign materials	None	None
Internal fixation of all closed fracture/ Total Joint Replacement/ Spine surgery (with and without instrumentation) Arthroscopy	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Cefuroxime 1.5gm IV Penicillin/Cephalosporin Allergy: Clindamycin 600-900mg IV	The benefits of routine postoperative antibiotics are uncertain. If used, postoperative prophylaxis should not exceed 24 hours.

Urological Surgery (Diagnostic Procedures)

Infection/Condition and Likely Organism	Suggested Treatment		Comments
Infection/Condition and Likely Organism	Preferred	Alternative	Comments
Transrectal ultrasound and prostate biopsy Common organisms: Escherichia coli, Klebsiella spp., Proteus spp, Enterococcus, Pseudomonas	Ciprofloxacin 500mg PO q12h for 3 days (start 24 hours before procedure) PLUS* Gentamicin 80mg IV single dose given 30-60 minutes before procedure	Targeted antibiotic therapy based on preoperative rectal swab result	Consider povidone-iodine bowel preparation to further decrease infection risk.
Cystoscopy / Urodynamic study	Antibiotic not recommended	Antibiotic not recommended	Prophylaxis only for high risk cases (immunocompromised patients, e.g. debilitated patients on long-term catheters, patients with prosthesis/heart valves, diabetes, transplant recipients): Cefuroxime 250mg PO stat. If heart valve: Follow recommendation from Subacute Bacterial Endocarditis (SBE) prophylaxis.
Retrograde pyelogram/ Ureteric stenting	Cefuroxime 250mg PO stat

Urological Surgery (Endourology)

Infection/Condition and Likely Organism

Suggested Treatment

Comments

Preferred

Alternative

Endourological surgery E.g. PCNL, URS, RIRS, TURP

Common organisms:

Escherichia coli,

Klebsiella spp.,

Proteus spp.,

Enterococcus spp.,

Pseudomonas spp.

Amoxicillin-clavulanate 1.2gm IV

Ampicillin-sulbactam 3gm IV

Cefuroxime 1.5gm IV

Ceftazidime 2gm IV (if urine grew Pseudomonas spp.)

Antibiotic selection to be determined based on patient’s latest urine culture result.

Urological Surgery (Open Surgery)

Infection/Condition and Likely Organism	Suggested Treatment		Comments
Infection/Condition and Likely Organism	Preferred	Alternative	Comments
Clean operations e.g. orchidectomy, orchidopexy, varicocelectomy, deroofing renal cysts	Antibiotic not required	Antibiotic not required
Clean-contaminated (with opening of urinary tract) E.g. nephrectomy, prostatectomy, open stone surgery. Common organisms: Escherichia coli, Klebsiella spp., Proteus spp., Enterococcus spp., Pseudomonas spp.	Amoxicillin-clavulanate 1.2gm IV q8h for 1 day OR Ampicillin-sulbactam 3gm IV q8h for 1 day	Cefoperazone 1gm IV q12h for 1 day OR Ceftazidime 2gm q8h IV for 1 day (if Pseudomonas spp is isolated from urine)
Clean-contaminated (with use of bowel segments) E.g. Cystectomy with urinary diversion, cystoplasty. Common organisms: Escherichia coli, Klebsiella spp., Proteus, Enterococcus, Pseudomonas	Cefoperazone 1gm IV q12h PLUS Metronidazole 500mg IV q8h	Gentamicin 1.5mg/kg IV q8h PLUS Metronidazole 500mg IV q8h	For duration of catheter present.
Implant of prosthetic devices e.g. Insertion of penile prosthesis or artificial urinary sphincter, artificial slings Common Organism: Staphylococcus aureus	Amoxicillin-clavulanate 1.2gm IV q8h for 1 week OR Ampicillin-sulbactam 3gm IV q8h for 1 week	Cefuroxime 1.5mg IV q8h for 1 week
Laparoscopic surgery	As for open surgery	As for open surgery	Depending on type of procedure performed whether clean or clean-contaminated.

Neurological Surgery

Infection/Condition and Likely Organism

Suggested Treatment

Comments

Preferred

Alternative

Clean wounds

(Uninfected operative wounds in which no inflammation is encountered and no viscus is entered during the procedures)

Elective craniotomy or spinal procedures

Cefuroxime 1.5gm IV

(Given as a single IV dose at induction or within 60 minutes before incision. For prolonged procedures, additional intraoperative doses are given at every 4 hours interval during surgery in patients with normal renal function)

Vancomycin 15-20mg/kg IV (max 2g) (Infusion is started within 60-120 min before incision. Additional redoses interval is at every 12 hours during surgery in patients with normal renal function)

Situation where the use of Vancomycin is appropriate: -

In hospitals in which MRSA or Staphylococcus epidermidis are frequent causes of postoperative wound infection. In patients previously colonized with MRSA, or those who are allergic to penicillins or cephalosporins.

Rapid IV administration of Vancomycin may cause hypotension.

Clean wounds with Foreign Body or Instrumentation. CSFs hunting procedures, implantation of cranial or spinal implants

Cefuroxime 1.5gm IV

PLUS

Metronidazole 500mg IV (Given as a single IV dose at induction or within 60 minutes before incision. Additional redose interval is at every 4 hours during surgery in patients with normal renal function)

Vancomycin 15-20mg/kg IV (max 2g)

PLUS

Gentamicin 5mg/kg IV (Given as a single IV dose at induction or within 60 minutes before incision in patients with normal renal function)

PLUS

Metronidazole 500mg IV (Given as a single IV dose at induction or within 60 minutes before incision. Additional redose interval is at 4 hours during surgery in patients with normal renal function)

Addition of another drug such as Metronidazole and aminoglycoside is appropriate for procedures in which anaerobic and enteric gram negative bacilli are common pathogens.

Clean-Contaminated wounds

(Operative wounds in which a viscus is entered and without unusual contaminations)

Procedures that breach air cells or nasal or oral cavity.

Cefuroxime 1.5gm IV

PLUS

Metronidazole 500mg IV

Vancomycin 15-20mg/kg IV (max 2g)

PLUS

Gentamicin 5mg/kg IV

PLUS

Metronidazole 500mg IV

Contaminated wounds (Open, fresh accidental wounds, operation with major breaks in sterile technique, or gross spillage from a viscus)

Ceftriaxone 2gm IV (Given as a single IV dose at induction or within 60 minutes before incision. Additional redoses interval is at every 12 hours during surgery in patients with normal renal function)

Vancomycin 15-20mg/kg IV (max 2g)

PLUS

Gentamicin 5mg/kg IV

PLUS

Metronidazole 500mg IV

Dirty wounds

(Infected CSF shunt, old traumatic wounds with retained devitalized tissue, foreign bodies or wounds that involve existing clinical infection or perforated viscus)

Ceftriaxone 2gm IV

PLUS

Metronidazole 500mg IV

Vancomycin 15-20mg/kg IV (max 2g)

PLUS

Gentamicin 5mg/kg IV

PLUS

Metronidazole 500mg IV

Settings where intraventricular antibiotics (Vancomycin 10mg or Gentamicin 5mg may be useful)

Failure to sterilize the CSF with IV therapy
Poor response to IV systemic antibodies
Presence of highly resistant organisms susceptible to only antibiotics with poor CSF penetration.
Circumstances in which shunt devices cannot be removed (including infected Ommaya reservoirs).

Cardiac Surgery

Infection/Condition and Likely Organism	Suggested Treatment
Infection/Condition and Likely Organism	Preferred	Alternative
Coronary artery bypass	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Cefuroxime 1.5gm IV
Cardiac device insertion procedures (e.g. Pacemaker implantation)	Cefazolin 2gm IV (3gm IV for patients weighing ≥120 kg)	Cefuroxime 1.5gm IV

Ophthalmologic Surgery

The use of povidone-iodine 10% to the periorbital skin and 5% to the conjunctival sac as an antiseptic agent for preoperative surgical site preparations are recommended.

Intracameral injection of 1mg Cefuroxime in 0.1ml at the end of cataract surgery is recommended. Careful dilution should be undertaken to prevent potential toxicity.

Topical antibiotics at end of surgery.

Hepatobiliary Surgery

Infection/Condition and Likely Organism	Suggested Treatment		Comments
Infection/Condition and Likely Organism	Preferred	Alternative	Comments
Laparoscopic procedures Low risk	Cefazolin 2 gm (3 gm IV for patients weighing ≥120 kg)		Optimum antibiotic timing is to complete intravenous infusion given 60 min prior to surgery (optimal window 15-45 min) prior to skin incision; to ensure adequate time to reach bactericidal serum and tissue concentration before skin is incised. Repeat intraoperative dosing is recommended in: Prolonged surgery > 4 hours. Massive blood loss > 1.5 L Aminoglycosides should not be redosed.
Laparoscopic procedures High risk: Stent insertion Biliary obstruction (High direct bilirubin)	Cefazolin 2 gm (3 gm IV for patients weighing ≥120 kg) PLUS Gentamicin 5mg/kg IV (2mg/kg IV single dose if CrCl<20)
Open surgery (Low risk)	Cefazolin 2 gm (3 gm IV for patients weighing ≥120 kg)
Open surgery High Risk Multiple ERCP (≥2) done with stenting Biliary Obstruction Biliary infection or surgery within < 30 days	Cefazolin 2 gm (3 gm IV for patients weighing ≥120 kg) PLUS Gentamicin 5mg/kg IV (2mg/kg IV single dose if CrCl < 20) If high risk ESBL/Multi-resistant organisms, e.g. ESBL in the last 3 months/12 but treated Piperacillin-tazobactam 4.5 gm IV PLUS Gentamicin 5mg/kg IV (2mg/kg IV single dose if CrCl < 20)
Pre-exiting infection before surgery, GB empyema, ascending cholangitis	Initiate antibiotic according to culture results, or refer to treatment guidelines

References

Antibiotic Expert Groups. Therapeutic guidelines: antibiotic. Version 15. Melbourne: Therapeutic Guidelines Limited; 2014.
Bratzler Dw, Dellinger EP, Olsen KM et al. Clinical practice guidelines for antimicrobial propylaxis in surgery. Am J Health-Syst Pharm. 2013; 70: 195-283.
Journal of Obstetric Gynecology Canada, Volume 39, Issue 9, September 2017, Pages e300-e308.
National Antimicrobial Guideline, Third Edition. Petaling Jaya: Ministry of Health, Malaysia; 2019.
Salford Royal, NHS. Antibiotic Prophylaxis in Cranial Neurosurgery Antibiotic Guidelines, Unique ID: 144TD(C)25(F4) Issue number: 6, 2018.
SIGN 104 Antibiotic prophylaxis in surgery. July 2008, updated April 2014.
Simo R, French G. The use of prophylactic antibiotics in head and neck oncological surgery. Curr Opin Otolaryngol Head Neck Surg. 2006; 14:55-61 88.
Surgical Antimicrobial Prophylaxis Clinical Guideline v2.0. Department for Health and Ageing, Government of South Australia. October 2017.
Van Eyk N, van Schalkwyk J, Infectious Diseases Committee. J Obstet Gynaecol Can. 2012 Apr; 34(4): 382-391.