Risk factors:

• Large volume injection of local anaesthetic - this can happen with epidural, cervical plexus, interscalene brachial plexus and paravertebral blocks
• Spinal anaesthesia with an epidural in situ and a recent epidural top-up
• Injecting directly into the epidural needle (without using a catheter)
• Difficulty with placing an epidural or spinal (multiple attempts)
• Poor patient positioning (head down/positioning the patient supine immediately after spinal)
• Repeated spinal injections, e.g. in case of an inadequate initial spinal/epidural block

A total or high spinal can occur even without any of the above risk factors.

Signs and symptoms:

• Cardio-respiratory:
  • Hypotension
  • Bradycardia
  • Whispering/change in voice
  • Inability to cough
  • Poor respiratory effort
  • Respiratory arrest
  • Cardiac arrest
• Neurological:
  • Nausea and anxiety
  • Arm or hand tingling/weakness
  • High sensory level block
  • Pupillary dilatation
  • Loss of consciousness

Symptoms usually occur within minutes of local anaesthetic injection but can be delayed up to 30 minutes.