Peripheral Nerve Blocks: Patient Selection

PATIENT SELECTION

The selection of a regional anesthetic technique is a process that begins with a thorough history and physical examination. Although many patients are candidates for regional anesthesia/analgesia, as with any medical procedure a risk–benefit analy-sis must be performed. The risk–benefit ratio often favors regional anesthesia in patients with multiple comorbidities for whom a general anesthetic car-ries a greater risk. In addition, patients intolerant to systemic analgesics (eg, those with obstructive sleep apnea or at high risk for nausea) may benefit from the opioid-sparing effects of a regional analgesic. Patients with chronic pain and opioid tolerance may receive optimal analgesia with a continuous periph-eral nerve block (so-called perineural local anes-thetic infusion).

A comprehensive knowledge of anatomy and an understanding of the planned surgical procedure areimportant for selection of the appropriate regional anesthetic technique. If possible, discussion with the surgeon about various considerations (tourniquet placement, bone grafting, projected surgical dura-tion) is ideal. Also, knowing the anticipated course of recovery and anticipated level of postoperative pain will often influence specific decisions regarding a regional anesthetic technique (eg, a single-injec-tion versus continuous peripheral nerve block).