Antibiotic prophylaxis in surgery

The Scottish Intercollegiate Guidelines Network (SIGN) has just launched their updated guideline on antibiotic prophylaxis in surgery. SIGN’s first guideline of this topic (SIGN 45) was published in 2000 and updated in 2008. The guideline does not aim to provide every surgical speciality with a comprehensive text on preventing surgical site infection (SSI), but rather to provide the evidence for current practice pertaining to antibiotic use, and to provide a framework for audit and economic evaluation.

The guideline does not cover:-

prevention of endocarditis after surgery or instrumentation (this is already covered by a UK guideline which is regularly updated)
use of antiseptics for the prevention of wound infection after elective surgery
treatment of anticipated infection in patients undergoing emergency surgery for contaminated or dirty operations
administration of oral antibiotics for bowel preparation or to achieve selective decontamination of the gut
most topical antibiotic administration, for example, in wounds or for perineal lavage
use of antibiotics for prophylaxis in patients with prosthetic implants undergoing dental surgery or other surgery that may cause bacteraemia
transplant surgery.

The guideline was developed using the SIGN methodology and has chapters on:-

Risk factors for surgical site infection
Benefits and risks of antibiotic prophylaxis
Indications for surgical antibiotic prophylaxis
Administration of prophylactic antibiotics

Some of the specific recommendations of most relevance to oral and maxillofacial surgeons for surgical antibiotic prophylaxis to prevent SSI are shown in the table below:-

Operation	Recommendation and Grade		Odds ratio	NNT*
Open reduction and internal fixation of compound mandibular fractures	A	Antibiotic prophylaxis is recommended	0.26	5
	A	The duration of prophylactic antibiotics should not be more than 24 hours
Intraoral bone grafting procedures	B	Antibiotic prophylaxis is recommended	There was no direct comparison of prophylactic antibiotic with no antibiotic
Orthognathic surgery	A	Antibiotic prophylaxis is recommended	0.21	4
	A	The duration of prophylactic antibiotics should not be more than 24 hours
	B	Broad spectrum antibiotics appropriate to oral flora should be given
Facial surgery (clean)	✓	Antibiotic prophylaxis is not recommended
Facial plastic surgery (with implant)	✓	Antibiotic prophylaxis should be considered	Effectiveness is inferred from evidence about other procedures involving insertion of prosthetic devices
Head and neck surgery (clean, benign)	D	Antibiotic prophylaxis is not recommended
Head and neck surgery(clean, malignant; neck dissection)		Antibiotic prophylaxis should be considered	1.28 0.12	-29 9
Head and neck surgery (contaminated/clean contaminated)	A	Antibiotic prophylaxis is recommended	0.37	6
	C	The duration of prophylactic antibiotics should not be more than 24 hours
	A	Ensured broad spectrum antimicrobial cover for aerobic and anaerobic organisms