Liposomal bupivacaine interscalene nerve block in shoulder arthroplasty is not superior to plain bupivacaine: a double-blinded prospective randomized control trial.

BACKGROUND: Interscalene brachial plexus blocks are a common modality used to provide adjunctive pain relief with shoulder replacement surgery. In 2018, the Federal Drug Administration approved the use of liposomal bupivacaine (LB) for such nerve blocks. We sought to evaluate whether this formulation of bupivacaine would provide superior pain relief for shoulder replacement patients over standard bupivacaine alone. Our hypotheses were that in the LB cohort the average postoperative pain score over the first 72 hours would be significantly lower, time to block cessation would be longer, total opioid consumption would be lower, and the average patient satisfaction score regarding their pain management would be higher. MATERIALS AND METHODS: A randomized, double-blinded study was designed comparing primary shoulder replacement surgery after an interscalene block with 25 mL of 0.5% plain bupivacaine vs. 133 mg of LB with 7.5 mL of 0.5% and 7.5 mL of 0.25% plain bupivacaine. A total of 104 patients were included in the study, with an equal number in each study arm. Patients' visual analog pain scores (VAPS) were followed for their inpatient stay, first 3 full outpatient days, and at a 3-week follow-up. Use of opioid medication was recorded for the same intervals and converted to morphine milligram equivalents. The time to first opioid rescue was documented, as well as the patients' satisfaction with their pain management at both the 3-day and 3-week intervals. RESULTS: No clinically relevant advantage to the use of LB over plain bupivacaine was found. During the second postoperative day, the mean VAPS was 2.4 with LB vs. 3.3 in the standard cohort (P = .0409). The only other statistically significant finding was a higher VAPS with LB during the third full day home compared with standard bupivacaine (4.0 vs. 2.8, respectively, P = .0197). Both of these differences were less than the minimal clinically important difference of 2 for the VAPS. Analysis of the VAPS for the first and third postoperative days, the first and second full days home, and at 3 weeks revealed no significant difference. Similarly, there was no significant difference in time to first opioid rescue, total morphine milligram equivalent use, and patient satisfaction with pain management. CONCLUSION: When used for an interscalene block to provide adjunctive pain relief in shoulder replacement surgery, the addition of LB to plain bupivacaine provides no additional clinically important benefit to the patient's pain experience over standard bupivacaine.

Adjuvant Agents in Regional Anesthesia in the Ambulatory Setting.

PURPOSE OF REVIEW: A majority of surgical practice has involved ambulatory centers with the number of outpatient operations in the USA doubling to 26.8 million per year. Local anesthesia delivery provides numerous benefits, including increased satisfaction, earlier discharge, and reduction in unplanned hospital admission. Further, with the epidemic of opioid mediated overdoses, local anesthesia can be a key tool in providing an opportunity to reduce the need for other analgesics postoperatively. RECENT FINDINGS: Adjuvants such as epinephrine and clonidine enhance local anesthetic clinical utility. Further, dexmedetomidine prolongs regional blockade duration effects. There has also been a significant interest recently in the use of dexamethasone. Studies have demonstrated a significant prolongation in motor and sensory block with perineural dexamethasone. Findings are conflicting as to whether intravenous dexamethasone has similar beneficial effects. However, considering the possible neurotoxicity effects, which perineural dexamethasone may present, it would be prudent not to consider intravenously administered dexamethasone to prolong regional block duration. Many studies have also demonstrated neurotoxicity from intrathecally administered midazolam. Therefore, midazolam as an adjuvant is not recommended. Magnesium prolongs regional block duration but related to paucity of studies as of yet, cannot be recommended. Tramadol yields inconsistent results and ketamine is associated with psychotomimetic adverse effects. Buprenorphine consistently increases regional block duration and reduce opioid requirements by a significant amount. Future studies are warranted to define best practice strategies for these adjuvant agents. The present review focuses on the many roles of local anesthetics in current ambulatory practice.

New Labor Pain Treatment Options.

Presently, the gold standard for pain control in laboring patients is neuraxial blockade, which includes a spinal, epidural, or a combined spinal-epidural technique. In conjunction with neuraxial blockade or by itself, some of the other agents employed related to labor pain include opioids, non-opioids, nitrous oxide, patient-controlled analgesia (PCA), and distraction therapy. Alternative treatments include acupuncture, hypnotism, yoga, exercise during pregnancy, hydrotherapy, transcutaneous electronic nerve stimulation, massage, and relaxation techniques. This review will focus on current updates and recent trends in labor pain management. Neuraxial management, pharmacotherapy, and newer alternative methods to mitigate labor pain are reviewed. Newer techniques in epidural analgesia include the dural puncture epidural technique, which needs further evaluation. There are limited published data on the use of acupuncture, hypnotism, yoga, exercise during pregnancy, hydrotherapy, transcutaneous electronic nerve stimulation, massage, and relaxation techniques in the alleviation of labor pain. These alternative therapies maybe considered as an adjuvant as the analgesic efficiency is inferior to that provided by typical standard pharmacotherapy. Future studies are warranted to evaluate the role of immersion virtual reality in alleviating labor pain.

Evaluating the Anatomic Spread of Selective Nerve Scalp Blocks Using Methylene Blue: A Cadaveric Analysis.

BACKGROUND: The modern scalp block consists of local anesthesia injections that target the supraorbital, supratrochlear, zygomaticotemporal, auriculotemporal, and greater and lesser occipital nerves. Limited data exist on the local anesthetic spread that occurs with this technique. This study examines the extent of the spread of a scalp block using methylene blue in a cadaveric model. METHODS: A traditional landmark-based scalp block was performed on 6 unembalmed human cadavers using 25-G, 1.5-inch needles to inject 1 to 2 mL of methylene blue 0.1% at each nerve bilaterally; a total volume of 20 mL was injected. The cadavers were then dissected, and the spread of injectate was measured and recorded. RESULTS: All the nerves required for analgesic coverage were appropriately stained by the injections, except for in 2 specimens where the lesser occipital nerve could not be identified. The zygomatic (stained in 2 of 8 specimens) and temporal (stained in 5 of 8 specimens) branches of the facial nerve were stained as a result of the zygomaticotemporal and/or auriculotemporal injections. Tracking from the zygomatic injection site was noted as far inferior as the temporalis muscle attachments on the mandible. CONCLUSIONS: This cadaveric study confirms that the landmark-based technique for scalp blocks consistently stained all 6 nerves involved in scalp innervation. There was significant unintentional spread to the branches of the facial nerve when using the landmark technique.

Evaluating two approaches to the erector spinae plane block: an anatomical study.

BACKGROUND AND OBJECTIVES: Studies show variable spread with thoracic erector spinae plane (ESP) injections. Injection sites vary from lateral end of the transverse process (TP) to 3 cm from the spinous process, with many not describing the precise site of injection. This human cadaveric study examined dye spread of ultrasound-guided thoracic ESP block at two needle locations. METHODS: Ultrasound-guided ESP blocks were performed on unembalmed cadavers. Methylene blue (20 mL, 0.1%) was injected in the ESP at the medial TP at level T5 (medial transverse process injection (MED), n=7) and the lateral end of the TP between T4 and T5 (injection between transverse processes (BTWN), n=7). The back muscles were dissected, and the cephalocaudal and medial-lateral dye spread documented. RESULTS: Dye spread cephalocaudally from C4-T12 in the MED group and C5-T11 in the BTWN group, and laterally to the iliocostalis muscle in five MED injections and all BTWN injections. One MED injection reached serratus anterior. Dorsal rami were dyed in five MED and all BTWN injections. Dye spread to the dorsal root ganglion and dorsal root in most injections, though more extensively in the BTWN group. The ventral root was dyed in 4 MED and 6 BTWN injections. Epidural spread in BTWN injections ranged from 3 to 12 levels (median: 5 levels), with contralateral spread in two cases and intrathecal spread in five injections. Epidural spread in MED injections was less extensive (median (range): 1 (0-3) levels); two MED injections did not enter the epidural space. CONCLUSION: An ESP injection administered between TPs exhibits more extensive spread than a medial TP injection in a human cadaveric model.

Anesthetic Considerations for Patients on Psychotropic Drug Therapies.

Psychotropic drugs are used in the treatment of psychiatric and non-psychiatric conditions. Many patients who are on psychotropic medications may present for procedures requiring anesthesia. Psychotropic medications can have dangerous interactions with drugs commonly used in anesthesia, some of which can be life-threatening. In this review, we describe the current anesthetic considerations for patients on psychotropic drug therapies, including antidepressants, antipsychotics, mood stabilizers, anxiolytics, and stimulants. The pharmacology, side effects, and potential drug interactions of the commonly prescribed psychotropic drug therapies with anesthetic agents are described. Further, we highlight the current recommendations regarding the cessation and continuation of these medications during the perioperative period.

Evaluating the spread of costoclavicular brachial plexus block: an anatomical study.

BACKGROUND AND OBJECTIVES: The costoclavicular brachial plexus block is performed deep and posterior to the midpoint of the clavicle. There are limited data evaluating the spread of the costoclavicular brachial plexus block. We performed a cadaveric study to evaluate the spread of injectate after a costoclavicular brachial plexus block. METHODS: Five ultrasound-guided costoclavicular block injections were performed with 20 mL of 0.1% methylene blue. The brachial plexus and its branches were dissected from the level of C4 to the lower axilla. The extent of dye spread was recorded including spread to the phrenic nerve, suprascapular nerve, roots, trunks, divisions, cords and terminal branches of the brachial plexus. RESULTS: The dye extended cephalad to the level of the cricoid cartilage in two of the five injections; three injections had dye extending 0.75 cm, 1.5 cm and 2 cm caudad to the level of the cricoid cartilage, respectively. The C7, C8 and T1 nerve roots were stained in all injections. The dye did not extend cephalad to the C5 and C6 nerve roots. All trunks, cords and divisions of the brachial plexus were stained, as was the suprascapular nerve. There was no spread of dye to the phrenic nerve in any of the specimens. CONCLUSIONS: This cadaveric study demonstrates that ultrasound-guided injection in the costoclavicular space spreads cephalad to the brachial plexus in the supraclavicular space, consistently reaching the suprascapular nerve and all trunks and cords of the brachial plexus, while sparing the phrenic nerve.

Perioperative analgesia for forequarter amputation in a child: a dual paravertebral approach.

We describe the management of postoperative pain for a 10-year-old girl who underwent forequarter amputation for osteosarcoma of the left humerus. Because the brachial plexus itself was divided and resected during surgery, and the main body part innervated by the nerves from this plexus (the entire upper limb including the scapula and clavicle) was removed, providing analgesia via a brachial plexus block alone would probably not have provided adequate coverage. Because the tissue not resected with this surgery was innervated via the cervical and brachial plexuses and some upper thoracic nerve roots, we elected to combine a perioperative high continuous cervical paravertebral block at the C5 level with a continuous thoracic paravertebral block at the T2 level for postoperative analgesia. Our patient experienced excellent postoperative analgesia and required no narcotics during the immediate postoperative period.

Evaluating the extent of lumbar erector spinae plane block: an anatomical study.

BACKGROUND AND OBJECTIVES: The erector spinae plane (ESP) block is a relatively new interfascial block technique. Previous cadaveric studies have shown extensive cephalocaudal spread with a single ESP injection at the thoracic level. However, little data exist for lumbar ESP block. The objective of this study was to examine the anatomical spread of dye following an ultrasound-guided lumbar ESP block in a human cadaveric model. METHODS: An ultrasound-guided ESP block was performed in unembalmed human cadavers using an in-plane approach with a curvilinear transducer oriented longitudinally. 20 mL of 0.166% methylene blue was injected into the plane between the distal end of the L4 transverse process and erector spinae muscle bilaterally in four specimens and unilaterally in one specimen (nine ESP blocks in total). The superficial and deep back muscles were dissected, and the extent of dye spread was documented in both cephalocaudal and medial-lateral directions. RESULTS: There was cephalocaudal spread from L3 to L5 in all specimens with extension to L2 in four specimens. Medial-lateral spread was documented from the multifidus muscle to the lateral edge of the thoracolumbar fascia. There was extensive dye in and around the erector spinae musculature and spread to the dorsal rami in all specimens. There was no dye spread anteriorly into the dorsal root ganglion, ventral rami, or paravertebral space. CONCLUSIONS: A lumbar ESP injection has limited craniocaudal spread compared with injection in the thoracic region. It has consistent spread to dorsal rami, but no anterior spread to ventral rami or paravertebral space.

The role of regional anesthesia in the propagation of cancer: A comprehensive review.

New cancer incidences worldwide will eclipse 18 million in 2019, with nearly 10 million cancer-related deaths. It is estimated that in the United States, almost 40% of individuals will be diagnosed with cancer in their lifetime. Surgical resection of primary tumors remains a cornerstone of cancer treatment; however, the surgical process can trigger an immune-suppressing sympathetic response, which promotes tumor growth of any residual cancerous cells post surgery. Regional and local anesthesia have become staples of anesthesia and analgesia during and after surgery. Recently, much evidence in the form of retrospective and prospective studies has come to light regarding the protective, antitumor properties of anesthetic and analgesic agents across a wide variety of cancers and patient demographics. It is believed that by blocking afferent pain signals, the body does not mount the sympathetic response that contributes to the perpetuation of disease after surgical treatment. This review, therefore, investigates these studies as they pertain to the treatment and outcomes of cancers treated surgically to elucidate the role of regional anesthesia in the propagation of cancer.

Supraclavicular and paravertebral blocks: Are we underutilizing these regional techniques in perioperative analgesia?

There has been a renewed interest in supraclavicular and paravertebral blocks for regional anesthesia. Studies have shown a high block success rate with the supraclavicular approach to the brachial plexus. Despite the use of ultrasound, pleural puncture and pneumothorax may still occur. The supraclavicular block is associated with a higher incidence of phrenic nerve paralysis and caution should be exercised in patients with respiratory difficulties. Paravertebral blocks have been used successfully to provide analgesia and anesthesia for a variety of surgical procedures. When compared to thoracic epidural blockade for thoracic surgery, paravertebral blockade provides comparable analgesia with a better preservation of pulmonary function and a lower incidence of hypotension. This brings forth the question as to whether paravertebral blocks have replaced epidural blockade as the gold standard in perioperative pain management for thoracoabdominal procedures.

Neurogenic thoracic outlet syndrome: A case report and review of the literature.

Neurogenic thoracic outlet syndrome (NTOS) is an oft-overlooked and obscure cause of shoulder pain, which regularly presents to the office of shoulder surgeons and pain specialist. With this paper we present an otherwise healthy young female patient with typical NTOS. She first received repeated conservative treatments with 60 units of botulinium toxin injected into the anterior scalene muscle at three-month intervals, which providing excellent results of symptom-free periods. Later a trans-axillary first rib resection provided semi-permanent relief. The patient was followed for 10 years after which time the symptoms reappeared. We review the literature and elaborate on the anatomy, sonoanatomy, etiology and characteristics, symptoms, diagnostic criteria and treatment modalities of NTOS. Patients with NTOS often get operated upon - even if just a diagnostic arthroscopy, and an interscalene or other brachial plexus block may be performed. This might put the patient in jeopardy of permanent nerve injury, and the purpose of this review is to minimize or prevent this.