Anesthesia

J. Megan

M. Patterson

Stefan Lucas

Anesthesia for hand and upper extremity surgery can be provided by either general or regional anesthesia. General anesthesia for upper extremity surgery is very similar to that for surgery on other areas and will not be discussed in this chapter.

I. Brachial Plexus Anesthesia and Analgesia

Regional anesthesia for upper extremity surgery enjoys widespread practice in the United States, albeit with a variety of approaches and philosophies. These blocks may be performed as a sole anesthetic or in combination with sedation or general anesthesia. Depending on the dosage of local anesthetic used, sensory “selectivity” or a complete sensory and motor blockade can be achieved (Tables 3.1 and 3.2)

Onset time and duration of action may be subject to other additives (i.e., epinephrine), which help to prolong the duration of blockade, limit the peak plasma concentration, and act as a marker for intravascular injection (Table 3.3).

TABLE 3-1 Brachial plexus anesthesia

Block Approach	Brachial Plexus Correlate	Best Targeted for	May Miss	Other Concerns
Interscalene approach	Root/proximal trunk level	Shoulder surgery	C8 and T1 roots “ulnar sparing” (really inferior trunk sparing)	Highest incidence of phrenic nerve palsy, possible seizure
Supraclavicular approach	Distal trunk/ division level	Mid-arm to hand	Suprascapular nerve	Tradition ally, highest incidence of pneumothorax
Infraclavicular approach	Cord/proximal branch level	Mid-arm to hand	Musculocutaneous nerve, and axillary nerve	Deep block
Axillary approach	Branch level	Forearm and hand	Axillary nerve, medial cutaneous nerves of arm and forearm, and musculocutaneous	Limb may not be akinetic (for surgical anesthesia)

TABLE 3-2 Typical single-shot brachial plexus block durations

Agent	Onset Time	Duration of Anesthesia	Duration of Analgesia
Lidocaine 2%/ Mepivacaine 1.5%	Very short (5 min)	∼3 h	∼5-6 h
Lidocaine 1%/ Mepivacaine 0.75%	Very short (5 min)	None to ∼1.5 h	∼3-4 h
Ropivacaine 0.5% to 0.75%	Short (8-12 min)	∼4-5 h (differential)	∼9-12 h
Bupivacaine 0.5%	Delayed (10-15 min)	∼6-9 h	∼10-16 h
Bupivacaine 0.25%	Delayed (10-20 min)	∼3-4 h	∼9-12 h

When performing nerve blocks at or distal to the elbow, we block each nerve individually. For these peripheral nerve blocks, a 25 gauge 1.5 in needle is typically used.

II. Median Nerve

A. Anatomy

Only gold members can continue reading. Log In or Register to continue