Disease - Pre-operative management

From CambridgeNotes

History and Examination

  • Anaesthetic history e.g. post-op nausea and vomiting; clotting problems, diabetes, hypertension, ischaemic heart disease, chronic obstructive pulmonary disease (COPD), asthma
  • Steroid use, anticoagulant use
  • Family history of medical and anaesthetic problems
  • Alcohol use, smoking, functional ability

Investigations (young and fit require none – NICE)

  • FBC and clotting, U&E, glucose, group & save/X-match; ECG; chest X-ray
  • Sickle cell disease, neck X-ray (if rheumatoid arthritis present)


  • Fast: stop solid food 6 hours before operation, stop clear fluids 2 hours before operation; after operation restart from clear fluids then proceed to free fluids, soft diet etc. (note evidence suggests allowing diet as tolerated immediately post-op is best!)
  • Diabetes management
    • Diet controlled: BM stix every 4 hours
    • Tablet controlled: convert long-acting e.g. metformin to short-acting e.g. gliclazide 3 days pre-operatively; omit morning tablet and give post op with light meal; BM stix every 4 hours of operation and if hyperglycaemia present give subcutaneous insulin or convert to sliding scale
    • Insulin controlled: insulin sliding scale i.e. 5% dextrose with 20mM KCl and fast-acting insulin in 0.9% Normal Saline according to hourly BM stix
  • Steroids: IV steroids peri-op to long-term steroid users
  • Warfarin: change to unfractionated heparin 3-5 days pre-op so INR<1.5; give heparin till 6 hours pre-op, check PTT<1.5; restart warfarin when safe e.g. 6 hours post-op and co-prescribe heparin until INR at desired levels (NB. LMWH is sometimes use as alternative in lower risk patients - switch to PE/DVT treatment dose 1.5mg/kg OD 3-5 days pre-op so INR<1.5; give last dose 10-12h pre-op; restart evening of op with warfarin)
  • Assume other drugs given; for oral contraceptives or hormone replacement therapy see drugs
  • Deep vein thrombosis (DVT): TED stockings, low molecular weight heparin (to be given 12-24h before surgery or immediately after), early ambulation
  • Infection (gastrointestinal): cephalosporin (gram negative) and metronidazole (anaerobes)
  • Pain: diclofenac 75-150mg PO/PR/IV daily