CLASS
Antibiotic, 1st generation cephalosporin
PRESENTATION
Off-white powder
Formulations
- 500mg, 1g, 2g vial
INDICATIONS & DOSING
Surgical Site Infection (SSI) prophylaxis, endocarditis prophylaxis
- Adult <60kg; 1g IV, repeat Q3H intraoperatively
- Adult 60-120kg; 2g IV, repeat Q3H intraoperatively
- Adult >120kg; 3g IV, repeat Q3H intraoperatively
- Paediatric; 30mg/kg IV, repeat Q3H intraoperatively
PRACTICALITIES
Administration
- Reconstitute with water or crystalloid
- Administer via slow IV push
Practice tips
- Should be administered within 60 minutes of surgical incision
- Administer slowly in the awake patient to reduce risk of nausea & vomiting
- Consider administration prior to induction to improve sensitivity and speed of diagnosis of anaphylaxis
- Dose according to total bodyweight (not ideal bodyweight)
- Continuation postoperatively should be reserved for high-risk cases, and generally for no longer than 24 hours
PHARMACOKINETICS
Duration of action
- ~2 hours
Elimination
Excreted renally unchanged
MECHANISM
Bactericidal via disruption of bacterial peptidoglycan cell wall integrity. Cephazolin irreversibly binds to Penicillin Binding Proteins (PBPs) on bacterial cell walls, preventing their action as transpeptidases. This prevents the forming of cross links in the cell wall, causing weakening of the cell wall and ultimately cell lysis.
Spectrum of activity
- Good activity against gram positive bacteria, including skin flora
- Limited activity against gram negative aerobes
- Limited activity against MRSA
- No activity against anaerobes
DESIRED CLINICAL EFFECTS
Immune
- Reduction in the incidence of Surgical Site Infections (SSIs), endocarditis
OTHER CLINICAL EFFECTS, ADVERSE EFFECTS & TOXICITIES
Immune
- Anaphylaxis and anaphylactoid reactions including Steven-Johnson syndrome
- Risk of Clostridium difficile overgrowth and infection
Renal & electrolytes
- Acute Kidney Injury (AKI)
Gastrointestinal
- Nausea & vomiting
- Diarrhoea
- Transient transaminitis
Other
- Pain on injection (variable)
CONSIDERATIONS
Precautions
- Renal impairment; adjust dose according to schedule
- Penicillin cross-hypersensitivity; avoid administration in patients with true penicillin anaphylaxis
Obstetric
ADEC category B1
Drug interactions
- Warfarin; may potentiate the anticoagulant effect of warfarin
REFERENCES
Drug information has been compiled from multiple sources including
- Drugs in Anaesthesia and Intensive Care (Scarth & Smith)
- Micromedex (IBM)
- BJA Education (Oxford Academic)
- Pharmacology for Anaesthesia and Intensive Care (Cambridge)
- Australian Prescriber (NPS MedicineWise)