Lidocaine on Early Cognitive Dysfunction in Shoulder Arthroscopy

Arthroscopic diagnosis and treatment of shoulder disorders have replaced open procedure as the primary treatment method. The beach chair (BCP) and lateral decubitus (LDP) positions are both considered as reliable techniques for performing effective arthroscopic shoulder surgeries. The usage of BCP for shoulder arthroscopic operations started from early 1980s.

The advantages of BCP include lack of brachial plexus strain, good intra-articular visualization, with the ease of conversion to an open approach if required.

The BCP combined with deliberate hypotension has been used to decrease intraoperative blood loss and allow a relatively blood-free surgical field. However, this combination has the risk to impair cerebral perfusion pressure and oxygenation during surgery and produce cerebral ischemia.

Lidocaine, a commonly used local anesthetic and class IB antiarrhythmic drug, that readily crosses the blood - brain barrier. Evans et al. initially reported cerebral protection of lidocaine in a feline model of cerebral arterial gas embolism. Later on, the effects of lidocaine on perioperative neuroprotection were detected. However, the mechanisms underlying lidocaine treatment-induced neuroprotection remain incompletely understood.

Lidocaine may provide cerebral protection through many mechanisms, including decreasing the cerebral metabolic rate, decelerating the ischemic transmembrane ion shift, and reducing the ischemic excitotoxin release.