The Effect of Mixing 1.5% Mepivacaine and 0.5% Bupivacaine on Duration of Analgesia and Latency of Block Onset in Ultrasound-Guided Interscalene Block

Abstract

For ultrasound-guided interscalene block, a combination of mepivacaine 1.5% and bupivacaine 0.5% results in a block onset similar to either local anesthetic alone. The mean duration of blockade with a mepivacaine-bupivacaine mixture was significantly longer than block with mepivacaine 1.5% alone but significantly shorter than the block with bupivacaine 0.5% alone.

The Maximum Effective Needle-to-Nerve Distance for Ultrasound-Guided Interscalene Block

“…29,30 Similarly, the durations of sensory blockade and motor blockade among patients with a successful block fell within previously reported ranges using similar doses of local anesthetic. 31,32 Our results suggest that injection within the middle scalene muscle may be an appropriate end point to achieve a successful analgesic ISB. The presence of microscopic septae, low resistance fascial planes, and variations in muscle density may impact local anesthetic spread within the middle scalene muscle and at least partially account for the present findings.…”

The Fibromyalgia Survey Score Correlates With Preoperative Pain Phenotypes But Does Not Predict Pain Outcomes After Shoulder Arthroscopy

“…This led to the hypothesis that the fibromyalgia survey score may predict postoperative pain outcomes in other cohorts. Shoulder arthroscopic surgeries can potentially result in moderate-to-severe pain,[1, 23] although they are less invasive than lower-extremity joint replacement surgeries. On POD 2, the lowest tertile of fibromyalgia survey scores had significantly better physical function when compared to the other groups, as well as non-significant trends in lower opioid consumption, pain scores, and neuropathic pain.…”

“…[1] However, it is unclear if preoperative characteristics could be used to identify shoulder arthroscopy patients at risk for poorer postoperative outcomes. Measures that may influence postoperative outcomes include psychological factors,[2] degree of pain[3] and physical functioning,[4] overall pain sensitivity,[5] and preoperative opioid use.…”

Effect of Adding Tetracaine to Bupivacaine on Duration of Analgesia in Supraclavicular Brachial Plexus Nerve Blocks for Ambulatory Shoulder Surgery

“…B rachial plexus blockade for upper-extremity surgery has been shown to be an eff ective form of postoperative analgesia, resulting in reduced opioid requirements, length of stay in the postanesthetic care unit, and time to discharge in the ambulatory surgery setting (1-3). Numerous studies have described the addition of adjunctive agents to a primary local anesthetic for peripheral nerve blockade resulting in longer duration of analgesia and decreased opioid requirements (4)(5)(6)(7)(8)(9)(10). Adjunctive agents include rapid-onset local anesthetics, sedative hypnotics, opioids, tramadol, and dexamethasone.…”

“…Adjunctive agents include rapid-onset local anesthetics, sedative hypnotics, opioids, tramadol, and dexamethasone. A few studies have evaluated the addition of the long-acting amino-ester local anesthetic tetracaine to peripheral nerve blockade to prolong duration of anesthesia and analgesia (6,11,12). Tetracaine hydrochloride has a duration of action similar to that of the amino amide local anesthetic bupivacaine, both averaging 3 to 10 hours (13).…”