Colorectal surgery
Link to General Principles of Surgical Prophylaxis including redosing table and renal dosing for cefazolin.
No post-op doses required. If heavily contaminated surgery give 48 hours of antibiotics post op.
Preferred
metronidazole 30mg/kg iv (Max=500mg)
AND
cefazolin iv see dosing table below
| Weight | cefazolin iv dose |
| Weight less than 120kg | 30mg/kg (maximum 2g) |
| Weight 120kg or more | 3g |
If post-op doses required: co-amoxiclav 30mg/kg (max 1.2g) iv TDS (BD for patients 1-2 months old)
Alternative
For penicillin allergy (non-severe)
metronidazole 30mg/kg iv (Max 500mg)
AND
cefazolin iv see dosing table below
| Weight | cefazolin iv dose |
| Weight less than 120kg | 30mg/kg (maximum 2g) |
| Weight 120kg or more | 3g |
If post-op doses required:
ceftriaxone 80mg/kg iv (Max=4g) OD
AND metronidazole 7.5mg/kg iv (Max=500mg) TDS
For penicillin allergy (severe) or MRSA positive
gentamicin 2.5mg/kg iv (Max 480mg) in theatre. If heavily contaminated continue gentamicin at 7mg/kg OD (Max 560mg) for 48 hours post op
AND
metronidazole 30mg/kg iv (Max 500mg) in theatre. If heavily contaminated continue metronidazole at 7.5mg/kg (Max 500mg) iv TDS.