Pre-operative assessment

Summarise core details

• Patient details
• Operation (and anaesthesia if required)
• Background

NB: look through past notes/documents to confirm details.

Current health

• Recent/current illnesses (within 2 weeks)
• Full systems review
• Baseline exercise tolerance (what makes them stop: SOB/chest pain/claudication)
• Symptoms of sleep apnoea (paroxysmal nocturnal dyspnoea, excessive sleepiness, morning headaches)
• Smoking/alcohol use

Medical and drug history

• Medical conditions: ask specifically about hypertension, diabetes (should be put first on list), asthma/COPD, cardiovascular disease, liver disease. Determine if conditions are adequately controlled.
• Drug history (including allergies!)

Anaesthetic history

• Previous anaesthetics and reactions
• Family anaesthetic history

Examination

Anaesthetic assessment

• Neck movement limitation/jaw opening limitation/dentures
• Airway assessment: use Mallampati classification and note BMI

  • See all soft palate and uvula
  • See half of uvula
  • See a small gap at end of soft palate
  • Can only see hard palate

• Back examination (if having spinal/epidural): look for skeletal malformations

Multi-system examination

• General: GCS, limb movements
• Hands: cyanosis, warm peripheries, cap refill, peripheral pulses
• Neck: JVP, carotid bruits
• Chest: heaves/thrills, chest expansion, percussion resonance, lung and heart sounds
• Abdomen: tenderness, masses/organomegaly, bowel sounds
• Calves: swelling/tenderness, oedema

Investigations

Tests that may be required for patients having surgery include:

• Blood tests: FBC, U&Es, LFTs, clotting, group and save
• ECG
• Other tests may be considered in advance
  • Pregnancy test (if chance of pregnancy)
  • Echocardiogram (if murmur/heart failure/cardiac symptoms)
  • Spirometry (if significant lung disease)
  • Pacemaker check(if have pacemaker)
  • TFTs (if on known thyroid disease)

Reference: NICE ‘NG45 Routine preoperative tests for elective surgery’ 2016

Preparation

Important note: medication changes/corrections should be made only after liaison with the surgeon or anaesthetist. General approaches are outlined below.

Correct investigation abnormalities

For an immediate pre-operative assessment (day prior to the operation)

• Correct INR if abnormal (>1.4)

  • Aggressive correction (if on warfarin for AF): 5-10mg IV vitamin K, then repeat INR in 6 hours – if still high, discuss with haematology regarding giving prothrombin complex concentrate pre-operatively
  • Cautious correction (if on warfarin for artificial heart valve/recent PE): discuss with senior and haematology – will usually require reversal of warfarin and cover with unfractionated heparin infusion, which will be stopped 4 hours pre-operatively and restarted after
  • If INR raised due to liver disease: 10mg IV vitamin K, then repeat INR in 6 hours – if still high, discuss with haematology who may advise FFP/cryoprecipitate

• Blood transfusion if Hb <9g/dL, or <10g/dL if elderly/cardiovascular/respiratory disease
• Consider platelet concentrate transfusion if platelets <50×10⁹/L (discuss with haematology if cause unclear)
• Correct electrolyte abnormalities

 

Note, if there are significant abnormalities, bloods must be repeated again pre-operatively (e.g. at 6am) to show they have been corrected.

For an early pre-operative assessment (>1 week pre-operatively)

• INR may be corrected by stopping warfarin as below
• Anaemia should be investigated and the cause treated – e.g. with iron tablets/infusion for iron-deficiency anaemia

If there are any concerns, contact the consultant or an anaesthetist.

Medications

• IV fluids: only prescribe fluids overnight (when NBM) if instructed by consultant, or if patient needs variable rate insulin infusion, or is dehydrated
• New medications
  • Operation preparation: give drugs required for specific operation (specified in pre-operative checklist), e.g. bowel prep for colorectal
  • VTE prophylaxis: prophylactic LMWH should usually be given the night before the operation, but omit any doses when the operation is due to start in <12 hours
  • Antiemetics and analgesia: as required
• Regular medicines
  • Vital drugs should usually be taken on the day of the operation: cardiovascular medications (excluding antihypertensives), antipsychotics, Parkinson’s medications, inhalers, glaucoma medications, immunosuppressants, thyroid medications, drugs of dependence (e.g. benzodiazepine)
  • Most other drugs should not be taken on the day of the operation (restarted the day after)
  • Some medications must be stopped/changed pre-operatively. Follow local guidelines/advice. Here is an example:

A patient presents to ED with chest pain and this trace. What would you do?

Interpretation management

Covered in OSCE Stations

Medications that should be stopped/changed pre-operatively

Forms

• VTE prophylaxis Proforma 
• Consent form (complete this only if you have sufficient knowledge, if not call registrar/consultant)

Fasting and admission

• Fasting guidelines
  • ‘2-6 rule’ = NBM for 2 hours pre-operatively; clear fluids only for 6 hours pre-operatively
  • If you are unsure of the operation time, prepare the patient for 8am (e.g. say clear fluids only from 2am, NBM from 6am).
• Pre-operative patients only generally need admission the night before if they are diabetic (and therefore require a variable rate insulin infusion from midnight); or if they need specific medications which must be given overnight; or if INR/Hb/platelets need correction