POCD defined as: long term cognitive dysfunction in at least 1 domain: memory, learning, concentration, speed of processing.

  • Manifests days to weeks in 25% elderly post-op patients.
  • 99% have resolved by 1 year.

Risk factors: (bold = strongest)

  • Patient: Age>60, low level of education, Hx chronic disease, other disorientating factors (e.g. pre-op cognitive impairment, visual & hearing loss, depression, physical restraints, ETOH abuse)
  • Surgical: Duration, extent of surgical trauma,
  • Anaesthetic: Benzos, Opioids, General > Regional, Depth of anaesthesia (BIS<40)

Discussion Points

Anaesthesia is but one factor in a complex mix contributing to POCD… but

  • Regional techniques which reduce hypnotic / benzo / opioid doses may be beneficial
  • Deep planes of anaesthesia are probably not beneficial … BIS may be beneficial in reducing hypnotic dosing and by inference reducing POCD incidence
  • Doing the simple things well – multimodal analgesia, PONV prophylaxis, IVF management, normothermia, normoxia, normocarbia etc. sees a crisper patient in recovery and may help reduce the risk of POCD