Paediatric

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 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 

 

* Note: Ciprofloxacin may induce convulsions in patients with or without a history of convulsions – use with caution

Also Note: If patient is prescribed ciprofloxacin ensure that the patient is given the Fluoroquinolone MHRA patient information leaflet. 

For more information about MHRA safety alerts and patient or carer counselling See Fluoroquinolone antibiotics -  paediatric position statement

JR Paediatric Appendicitis pathway

Editorial Information

Last reviewed: 01 Nov 2023

Author(s): AMST.

Approved By: MMTC