• General anesthesia removes many of the bodies natural protective mechanisms
• Iatrogenic injury is therefore possible
• Many of these injuries can produce lasting disability
• Can also lead to litigation
• Recognition of risks and prevention is essential

Injuries in the anaesthetised patient

• Nerve injuries
  • Brachial plexus
  • Ulnar nerve
  • Radial nerve
  • Common peroneal nerve
• Tissue injuries
  • Corneal abrasions
  • Teeth or crowns
  • Diathermy burns
  • Dislocations or fractures
• Anaesthetic
  • Drug reactions
  • Hypoxia
  • Awareness

Nerve injuries

• The incidence of nerve injuries is unknown
• In USA account for 15% of postoperative litigation claims
• Most are due to careless positioning of the patient
• Commonest nerves affected are ulnar and common peroneal nerves and brachial plexus
• Predisposing factors include:
  • Medical conditions associated with a neuropathy (e.g. diabetes mellitus)
  • Nerve ischaemia due to hypotension
  • Local injections or direct nerve injury
  • The use of a tourniquets
• Most are due to a neurapraxia
• 90% undergo complete recovery
• 10% are left with residual weakness or sensory loss

Ulnar nerve

• Caused by arms along side patient in pronation
• Ulnar nerve compressed at elbow between table and medial epicondyle
• Prevented by positioning arms in supination

Brachial plexus

• Caused by excessive arm abduction or external rotation
• Prevented by avoiding more than 60° abduction if possible
• Should avoid arm falling off side of table

Common peroneal nerve

• Caused by direct pressure on the nerve with legs in lithotomy position
• Nerve compressed against neck of fibula
• Prevented by adequate padding of lithotomy poles

Radial nerve

• Caused by tourniquet or misplaced injection in deltoid muscle
• Prevented by adequate padding of tourniquets

Bibliography

Ogbue M N,  Jefferson P,  Ball D R.  Perioperative peripheral nerve injury.  Anaesthesia 2001;  56:  393-394.

Prielipp R C,  Morell R C,  Butterworth J.  Ulnar nerve injury and perioperative arm positioning.  Anesthesiol Clin North Am 2002; 20:  351-365.