FRCA Notes

Anaesthesia and Analgesia for Day Surgery

The March 2023 CRQ featured a question on spinal anaesthesia for day surgery (53% pass rate), based almost entirely on the below-linked BJA Education article on spinal anaesthesia for ambulatory surgery.

Resources

  • The overall goal is a return to "street fitness" with normalised physiology, i.e. drinking, eating and mobilising (DrEaMing) as soon as possible

  • The main aims of anaesthesia for day surgery are to facilitate:
    • Rapid return to normal conscious state
      • By avoiding long-acting drugs in general
      • Use anaesthetic techniques which promote clear-headed emergence e.g. TIVA, short-acting volatile or avoid GA altogether

    • Effective, multi-modal, peri-operative, opioid-sparing analgesia to promote a rapid return to normal mobilisation

    • Avoidance of PONV, dizziness and drowsiness to facilitate a rapid return to normal oral intake

  • Attention should be paid to minimising symptoms which delay discharge:
    • Pain
    • PONV
    • Urinary retention
    • Drowsiness
    • Difficulty mobilising
    • Orthostatic hypotension

Maintenance

  • There is little evidence that either short-acting volatile or propofol-based TIVA is superior in terms of outcomes
  • However, TIVA may be advantageous:
    • ↓ PONV
    • ↓ post-operative cognitive dysfunction
    • ↓ pain in recovery and shorter first stage recovery
    • Often preferred by patients
    • Lower environmental impact than volatile agents
  • Desflurane is felt to be harmful environmentally (controversial!) and is being phased out across the NHS

Neuromuscular blockade

  • Sugammadex is useful in day surgery:
    • Allows reversal of rocuronium even from deep block, which is useful for short procedures where deep block is advantageous
    • Rapid reversal improves list efficiency
    • Compared with neostigmine, it reduces PONV and may reduce length of stay

  • Sugammadex can reduce the efficacy of hormonal contraception through its interaction with progesterone
    • All female patients of reproductive age who receive it should be given a patient information leaflet on the need for additional contraceptive precautions

  • Regional techniques can provide excellent anaesthesia and analgesia, be it simple wound infiltration, single-shot blocks or catheter-based techniques
  • They can reduce PONV and opioid requirements, and facilitate day surgery in higher-risk patients (e.g. ASA 3–4, OSA)
  • The advent of longer-acting agents may increase use e.g. liposomal bupivacaine is now licensed in the USA and has a long effect profile than standard bupivacaine
  • Unfortunately, regional anaesthesia accounts for 40% of complaints following day surgery despite accounting for <25% of anaesthetic techniques used

  • Patients may be safely discharged with residual sensorimotor blockade from a regional technique, so long as:
    • The limb is protected
    • The patient is educated on the expected duration of the blockade
    • The patient receives written instructions about conduct until sensation/power normalises
    • Support is available if required

  • Spinal anaesthesia has become accepted for day surgery, especially with the advent of newer, shorter-acting local anaesthetic agents

Benefits

  • Reduced post-operative pain scores and analgesic requirements
  • Lower rates of PONV
  • Improved patient engagement
  • Suitability for more comorbid (cardiac, pulmonary, obese) patients in whom GA may be less preferable; may allow ASA 3 and 4 patients to have day surgery
  • Faster discharge

Technique

  • Appropriate targeting of spinal anaesthetic can minimise side effects such as hypotension or prolonged motor blockade, e.g.
    • Using the minimum dose required to provide sufficient anaesthesia (as duration of block is proportional to dose)
    • Lateral lying for unilateral knee arthroscopy
    • Sitting position for peri-anal procedures

  • Use a 25G pencil point needle, as it reduces PDPH risk to <1%
  • Information on PDPH should be given with discharge instructions

  • Restricting IV fluids to ≤500ml should reduce the incidence of urinary retention
    • If intra-operative hypotension occurs, vasopressors should be used preferentially
    • Patients need to have voided in order to fulfil discharge criteria

  • There should be a robust analgesic plan in order to prevent significant pain when the block wears off
  • Criteria for safe mobilisation post-operatively should be followed, including
    • Return of S4-5 (peri-anal) sensation
    • Ability to plantarflex foot
    • Return of big toe proprioception

Local anaesthetic choices


Local anaesthetic options
Heavy prilocaine 2%
2-chloroprocaine 1%
Heavy bupivacaine 0.5%
Levobupivacaine 0.25 - 0.75%
  • Choice ultimately depends on factors such as required block height, required duration of block and nature of the surgery proposed
  • Prilocaine and 2-chloroprocaine are short-acting with rapid onset, allowing rapid recovery with less hypotension and urinary retention
  • NB lidocaine not recommended owing to prevalence of transient neurological symptoms (1 in 7) with its use in a dose-/concentration-independent manner

Neuraxial opioids

  • Short-acting opioids such as fentanyl and sufentanil have been used as adjuncts
  • They may provide more effective post-operative analgesia but suffer from classic opioid-associated side-effects including PONV, urinary retention and pruritus
  • Typically avoided for ambulatory surgery

Complications

  • Delayed mobilisation; less common with shorter-acting agents
  • Urinary retention
    • Requires regression of sensory blockade to below S3
    • Keeping IV fluid to <500ml can reduce risk
    • Avoiding IT opioids can reduced risk
    • No reported cases with 2-chloroprocaine
  • The usual complications of neuraxial anaesthesia

  • Post-operative pain after day surgery is common
    • The incidence of moderate-to-severe pain may be as high as 25 - 30%
    • The frequency of inadequate post-operative pain relief varies according to surgical type
  • It is associated with negative sequelae including being psychologically unpleasant, increased incidence of PONV, sleep disturbance, delayed mobilisation and failed discharge
  • Chronic post-surgical pain after day surgery is increasingly recognised
  • Protocolised evaluation and evidence-based analgesic regimens can improve pain management and patient satisfaction

Pre-operative

  • Identify patients at high risk of difficult perioperative pain management e.g. high anxiety, chronic pain, opioid tolerance
  • Patient education, preparation and expectation management
  • Premedication with oral paracetamol and NSAID

Intra-/Post-operative

  • Minimally invasive surgical techniques are preferred to reduce pain
  • Multi-modal analgesic regimen is mandatory

  • Simple analgesia
    • Paracetamol
    • NSAID if not contraindicated; slow-release ibuprofen may be beneficial to avoid missed doses

  • Opioids
    • Must balance analgesic benefits with side-effects (PONV, sedation, pruritus and urinary retention), all of which delay discharge
    • Use short-acting opioids e.g. fentanyl intra-operatively and IR-morphine immediately post-operatively
    • Use of long-acting opioids is discouraged; e.g. morphine causes more PONV than fentanyl
    • Avoid codeine in breastfeeding patients

  • Non-opioid adjuncts can reduce opioid requirements but the optimal dosing is not known and can themselves cause discharge-delaying side-effects
    • Gabapentinoids
    • Ketamine
    • ɑ2-agonists e.g. clonidine
    • IV lidocaine
    • Magnesium

Discharge

  • Include written information on pain management to improve compliance and understanding
  • Pain often worse on the day post-operatively as the patient mobilises
  • In general require regular analgesia for three days post-operatively
  • Sufficient analgesia should be supplied for 5–7 days, ideally as pre-packaged discharge medication

  • No implantable device is in isolation an absolute contraindication to day surgery, but patient and device factors need consideration

Cardiac devices

  • Pre-assessment should identify the device, confirm regular follow-up and liaise with the cardiology team if required
  • Pacemakers: determine pacing dependence, site of surgery and type of diathermy
  • ICDs: determine whether deactivation is needed; availability of a cardiac physiologist is therefore crucial to suitability for day surgery
  • Implantable loop recorders pose no risk and need no precautions

Surgery Pacemaker (pacing-dependent) Pacemaker (not pacing-dependent) ICD
Surgery above umbilicus (inc. dental/ophthalmic) Consider fixed rate if prolonged diathermy Monitor Deactivate
Surgery below umbilicus Monitor Monitor Monitor
Lithotripsy Monitor Monitor Deactivate
Endoscopy Consider fixed rate if prolonged diathermy/argon beam Monitor Deactivate
  • Where monitoring alone is required, day surgery is likely to be possible without cardiac physiology support (adapted from British Heart Rhythm Society guidance)

Neurological devices

  • Vagal nerve stimulators
    • Deactivate pre-operatively and reactivate (or interrogate) post-operatively, for both GA and spinal anaesthesia
    • Patients should carry their device magnet at all times
    • Given patient complexity, day surgery is usually only possible in neuroscience centres

  • Sacral nerve and spinal cord stimulators
    • Deactivate intra-operatively and reactivate afterwards; interrogation can occur after discharge
    • Monopolar diathermy is contraindicated (risk of heating leads)
    • Sacral nerve stimulators are not a contraindication to spinal anaesthesia; spinal cord stimulators are a relative contraindication (risk of lead damage)

  • Deep brain stimulators
    • Use bipolar diathermy where possible
    • If monopolar is unavoidable: lowest power setting, low voltage, ground plate as far from the system as possible
    • Check device function after diathermy

PONV

  • Risk-assess patients (e.g. Apfel score) and stratify anti-emetics accordingly, following local protocols for multiple anti-emetic combinations
  • If PONV risk is high, TIVA or regional anaesthesia may reduce risk
  • Manage PONV as standard

VTE

  • The growing range & complexity of surgery performed as day cases may increased the risk of VTE
  • National guidelines for the assessment and prophylaxis of VTE should be followed
  • Interventions include:
    • Use of TEDs peri-operatively
    • Early mobilisation
    • Patient education
    • Adequate hydration
    • Prolonged course chemical VTE prophylaxis for patients at higher risk inc. obese patients

Paediatrics

  • Emergence delirium is more common in young children after short procedures; it risks self-injury and dislodged dressings/cannulae, and prolongs recovery stay
  • Risk factors:
    • Younger age
    • Pre-operative anxiety
    • ENT surgery
    • Sevoflurane
  • Reduce risk with TIVA, intra-operative ɑ2-agonists (dexmedetomidine or clonidine) and multimodal analgesia
  • Non-pharmacological measures include anxiety reduction, parental presence at induction and age-appropriate distraction

  • High PONV-risk procedures (e.g. squint, tonsillectomy) warrant careful consideration of opioid use and appropriate anti-emetics

Sustainability

  • Volatile agents are a significant source of greenhouse gas emissions
  • Recommendations include:
    • Local/regional anaesthesia or TIVA where appropriate
    • Removing desflurane from the formulary
    • Limiting nitrous oxide and decommissioning pipeline supply
    • Low-flow anaesthesia and volatile/nitrous oxide capture technology
    • Switching to reusable equipment and minimising drug waste