Complicated appendicitis (at induction and for post-operative management)
Complicated appendicitis is defined as gangrenous appendix and/or perforated appendix with or without visible faecolith.
Refer to the appendicitis pathway for duration of antibiotic treatment (see pathway below)
Refer to the Suspected appendicitis guideline for pre-op management.
Preferred
At induction
Cefazolin iv see dosing table below:
| Weight | cefazolin iv dose |
| Weight less than 120kg | 30mg/kg (Max 2g) |
| Weight 120kg or more | 3g |
AND
metronidazole 30mg/kg (Max 500mg) iv
AND
gentamicin iv
- If patient DID NOT receive any gentamicin in the previous 24 hours: STAT dose gentamicin 5mg/kg (Max 480mg) iv in theatre.
- If patient received any gentamicin in the previous 24 hours: No further gentamicin in theatre.
For MRSA positive patients: Add vancomycin iv
Post-operatively
Post-op doses:
co-amoxiclav 30mg/kg (max 1.2g) iv TDS (BD if 1-2 months old) AND gentamicin at 7mg/kg (Max 560mg) iv OD (every 24 hours) for 48 hours post-op. Review as per pathway below.
Take a gentamicin level before the SECOND dose if gentamicin was started before surgery or if it is going to be continued beyond 48 hours post-op.
Alternatives: Penicillin allergy (non severe)
At induction:
Cefazolin iv see dosing table below
| Weight | Cefazolin iv dose |
| Weight less than 120kg | 30mg/kg (Max 2g) |
| Weight 120kg or more | 3g |
AND
metronidazole if not started pre-operatively OR if a dose is due: 30mg/kg (Max 500mg) iv
AND
gentamicin 5mg/kg (Max 480mg) iv
For MRSA positive patients: Add vancomycin iv
Post-operatively
Post-op doses:
Continue with ceftriaxone 80mg/kg (Max 4g) iv OD - ensure that it is restarted 24 hours after the last ceftriaxone dose
AND
metronidazole 7.5mg/kg (Max 500mg) iv TDS
Alternatives: Penicillin allergy (severe)
At induction
clindamycin 10mg/kg (Max 600mg) iv – only give if more than 6 hours since the last dose of clindamycin
AND
gentamicin iv
- If patient DID NOT receive any gentamicin in the previous 24 hours: STAT dose gentamicin 5mg/kg iv (max 480mg) in theatre.
- If patient did receive any gentamicin in the previous 24 hours: No further gentamicin in theatre.
For MRSA positive patients: Add vancomycin iv
Post-operatively
Post-op doses:
Continue with clindamycin 10mg/kg (Max 600mg) iv QDS AND gentamicin 7mg/kg (Max 560mg) iv OD (every 24 hours) for 48 hours post-op. Review as per pathway below.
Take a gentamicin level before the SECOND dose if gentamicin was started before surgery or if it is going to be continued beyond 48 hours post-op.
Oral antibiotics stepdown
See choice and duration of oral antibiotics in the pathway below. For Streptococcus milleri, the total duration of antibiotics should be 10 days.
Oral co-amoxiclav dosing
|
Age |
co-amoxiclav oral dose |
| 1 month to 11 months | 0.5mL/kg of 125mg/31mg/5mL suspension TDS |
| 1 year to 5 years | 10mLs of 125mg/31mg/5mL suspension TDS |
| 6 years to 11 years | 10mLs of 250mg/62mg/5mL suspension TDS |
| 12 years to 17 years | One 625mg tablet TDS OR 10mLs of 250mg/62mg/5mL suspension TDS if patient cannot take tablets |
Oral metronidazole dosing
| Age | metronidazole oral dose |
| 1 month | 7.5 mg/kg (max 400 mg) BD |
| 2 months –11 years | 7.5 mg/kg (max 400 mg) TDS |
| 12–17 years | 400 mg TDS |
Oral ciprofloxacin* dosing: 20 mg/kg (Max 750mg) po BD
* Ciprofloxacin may induce convulsions in patients with or without a history of convulsions – use with caution