Interscalene block anesthesia at an ambulatory surgery center performing predominantly regional anesthesia: a prospective study of one hundred thirty-three patients undergoing shoulder surgery

Early postoperative pain and opioid consumption after arthroscopic shoulder surgery with or without open subpectoral biceps tenodesis and interscalene block

Objective

The addition of open subpectoral biceps tenodesis to arthroscopic shoulder surgery with interscalene block has been anecdotally observed to result in increased postoperative pain. This study aims to evaluate the impact of tenodesis on early postoperative pain and recovery.

Methods

A retrospective review of patients undergoing arthroscopic shoulder surgery with general anesthesia and interscalene block was conducted.

Results

Patients undergoing tenodesis experienced longer OR time, pain numeric rating scale (NRS), and consumed more morphine milligram equivalents (MME) in PACU. After controlling for confounding factors, tenodesis was significantly associated with increased opioid MME consumption in the PACU (β = 1.045, p = .028) and last PACU pain NRS (β = 0.541, p = .009).

Conclusion

Overall, pain scores and narcotic consumption were low after surgery, making these differences potentially clinically insignificant. Further study is required to evaluate whether these trends are consistent among this population.

Continuous Peripheral Nerve Blocks Are Associated With Increased Rates of Emergency Department Visits After Arthroscopic Rotator Cuff Repair Surgery

The purpose of this study was to assess trends in the use of perioperative single and continuous peripheral nerve blocks (PNBs) and their associations with emergency department (ED) visits after arthroscopic rotator cuff repair (RCR) surgery. The authors used a large database from a private insurer to identify patients who received perioperative PNBs for arthroscopic RCR surgeries from 2007 to 2015. They analyzed patient demographics as well as trends in perioperative PNB use. They also assessed rates of single shot vs continuous PNB use and compared rates of postoperative ED visits according to PNB type. The rate of perioperative PNB for arthroscopic RCR was higher than previously reported (65.9%) and increased over time (52.8% in 2007 to 64.6% in 2015; P=.029). Single shot PNBs were more common than continuous, catheter-mediated PNBs (60.0% vs 6.6%; P<.001), although the use of continuous blocks increased at a greater rate during the study period. Patients who received a perioperative continuous PNB were significantly more likely to visit an ED within 7 days of their surgery than those who received a single shot PNB or no PNB (6.71% vs 4.78% vs 4.74%; P<.02). The rates of ED visits within each group did not change significantly over time. Continuous PNBs are increasingly common for patients undergoing arthroscopic RCR surgery but are associated with increased rates of postoperative ED visits. Studies are needed to identify the reasons for this increased rate of ED visits and strategies to decrease ED use. [Orthopedics. 2020; 43(2): 127-131.].

A comparison of continuous interscalene block versus general anesthesia alone on the functional outcomes of the patients undergoing arthroscopic rotator cuff repair

PURPOSE

The aim of this prospective and randomized study was to compare the effects of general anesthesia to the combination of general anesthesia and continuous interscalene block on postoperative pain and functional outcomes in patients undergoing arthroscopic rotator cuff repair.

METHODS

This study included a total of 85 patients aged 45-74 years, who were scheduled for elective arthroscopic rotator cuff repair. One group consists of patients who underwent only general anesthesia (GA, N = 43), and the other group consists of patients who underwent a combination of continuous interscalene brachial plexus block and general anesthesia (CISB + GA, N = 42). Pain levels of the patients were evaluated postoperatively by a visual analog scale. Shoulder function was evaluated preoperatively and postoperatively using the Constant score.

RESULTS

Patients in the CISB + GA group had lower postoperative visual analog scores and less additional analgesic needs during the early postoperative period than those in the GA group. Constant scores of the patients in the CISB + GA group at postoperative week 6 were higher than those in the GA group. Evaluation of the functional outcomes at 6 months postoperatively showed that there were no significant differences between the two groups.

CONCLUSION

Although CISB significantly improved postoperative pain control and early (in the first 6 weeks) functional outcomes following arthroscopic rotator cuff repair, there was no significant difference between the CISB group and CISB + GA group at 6 months.

LEVEL OF EVIDENCE

Level II, Randomized Controlled Trial, Treatment Study.

Rotator cuff repair is more painful than other arthroscopic shoulder procedures

AIM

To evaluate the influence of the specific procedure performed and other variables on the intensity of acute postoperative pain following outpatient shoulder arthroscopy.

METHODS

One hundred patients undergoing outpatient shoulder arthroscopy under single-shot interscalene block plus general anaesthesia were prospectively studied. Acetaminophen with ibuprofen was prescribed for postoperative pain control and tramadol HCl as rescue medication. Patients scored pain intensity at 2, 6, and 24 h postoperatively. The influence of the surgical procedure, age, gender, surgery duration, and irrigation volume used on the intensity of postoperative pain was studied.

RESULTS

Five patients were excluded due to ineffective block or protocol deviation. Among the 95 remaining patients, 51 underwent rotator cuff tear repair, 25 shoulder stabilisation, and 19 subacromial decompression. While there were no differences at 2 and 6 h after surgery, pain intensity was significantly higher among those undergoing rotator cuff tear repair (5.2, 1-10) at 24 h compared to stabilisation (4.1, 1-8) or subacromial decompression (5, 1-8) (p < 0.0001). No association was found between pain intensity and other variables.

CONCLUSION

A higher degree of acute postoperative pain should be expected in patients undergoing arthroscopic rotator cuff tear repair compared to other arthroscopic shoulder procedures, and additional pain treatment is recommended.

Peripheral Nerve Injury Following Interscalene Blocks: A Systematic Review to Guide Orthopedic Surgeons

The purpose of this review was to determine the incidence and duration of peripheral neurologic symptoms following interscalene blocks for shoulder surgery. Three databases were reviewed for subjective and objective injuries by guidance modality and delivery method. The incidence of neurologic injuries following single site injection interscalene blocks, 3.16%, was significantly less than the 5.24% incidence for continuous catheter infusion interscalene blocks. Less than 0.51% of peripheral neurologic symptoms persisted beyond 1 year for both groups. There is a notable risk of injury following interscalene blocks by all modes of guidance and anesthetic technique, but only a small percentage of injuries persist. [Orthopedics. 2018; 41(5):e598-e606.].

Recovery after shoulder arthroscopy: Inpatient versus outpatient management

INTRODUCTION

Shoulder arthroscopy is particularly suited to outpatient surgery, thanks to advances in anesthetic and analgesic techniques. The main goal of this study was to compare postoperative recovery after shoulder arthroscopy between outpatient and inpatient management.

HYPOTHESIS

There is no difference in functional recovery between inpatient and outpatient management.

MATERIALS AND METHOD

A single-center, single-operator prospective study was conducted. Both groups received patient-controlled analgesia via an interscalene catheter. The inclusion criterion was shoulder arthroscopy for rotator cuff tendinopathy. The choice between inpatient and outpatient management was left to the patient. The study endpoint was postoperative recovery assessed on QOR-15 at days 1, 2, 3, 4 and 7 and on Quick-DASH at 6 weeks.

RESULTS

Forty-nine patients were included, divided into 2 groups. The outpatient (OP) and inpatient (IP) groups were comparable. Reconstructive surgery accounted for 54% of cases in OP versus 62% in IP. There was no significant difference in recovery in the first postoperative days (QOR-15) or at 6 weeks (Quick-DASH) (p>0.05). Pain on visual analog scale (VAS) was significantly greater in OP after discharge home.

DISCUSSION

No significant difference in postoperative recovery was observed between groups. Nevertheless, pain management and patient information for outpatients need improving.

LEVEL OF EVIDENCE

II, comparative study.

Suprascapular and Interscalene Nerve Block for Shoulder Surgery

Background

Interscalene block provides optimal shoulder surgery analgesia, but concerns over its associated risks have prompted the search for alternatives. Suprascapular block was recently proposed as an interscalene block alternative, but evidence of its comparative analgesic effect is conflicting. This meta-analysis compares the analgesic effect and safety of suprascapular block versus interscalene block for shoulder surgery.

Methods

Databases were searched for randomized trials comparing interscalene block with suprascapular block for shoulder surgery. Postoperative 24-h cumulative oral morphine consumption and the difference in the area under curve for pooled rest pain scores were designated as primary outcomes. Analgesic and safety outcomes, particularly block-related and respiratory complications, were evaluated as secondary outcomes. Results were pooled using random-effects modeling.

Results

Data from 16 studies (1,152 patients) were analyzed. Interscalene block and suprascapular block were not different in 24-h morphine consumption. The difference in area under the curve of pain scores for the 24-h interval favored interscalene block by 1.1 cm/h, but this difference was not clinically important. Compared with suprascapular block, interscalene block reduced postoperative pain but not opioid consumption during recovery room stay by a weighted mean difference (95% CI) of 1.5 cm (0.6 to 2.5 cm; P &lt; 0.0001). Pain scores were not different at any other time. In contrast, suprascapular block reduced the odds of block-related and respiratory complications.

Conclusions

This review suggests that there are no clinically meaningful analgesic differences between suprascapular block and interscalene block except for interscalene block providing better pain control during recovery room stay; however, suprascapular block has fewer side effects. These findings suggest that suprascapular block may be considered an effective and safe interscalene block alternative for shoulder surgery.

Liposomal Bupivacaine Mixture Has Similar Pain Relief and Significantly Fewer Complications at Less Cost Compared to Indwelling Interscalene Catheter in Total Shoulder Arthroplasty

BACKGROUND

The efficacy and costs of indwelling interscalene catheter (ISC) and liposomal bupivacaine (LBC), with and without adjunctive medications, in patients with primary shoulder arthroplasty are a source of current debate.

METHODS

In 214 arthroplasties, 156 patients had ISC and 58 had LBC injections that were mixed with morphine, ketorolac, and 0.5% bupivacaine with epinephrine. Charts were reviewed for visual analog scale pain scores, oral morphine equivalent (OME) usage, major complications, and costs.

RESULTS

Visual analog scale scores were not significantly different at 24 hours or at 2, 6, and 12 weeks. Average OME consumption at 24 hours was significantly more with LBC, but was not significantly different at 12 weeks. Relative risk of a major complication was nearly 4 times higher with ISC than with LBC. The average cost for the LBC mixture was $289.04, and for ISC, including equipment and anesthesia fees, was $1559.42.

CONCLUSION

The intraoperative LBC mixture provided equivalent pain relief with significantly fewer major complications and at markedly lower cost than ISC. LBC required almost twice as much OME to attain the same level of pain relief at 24 hours, but there was no significant difference in the cumulative amount of outpatient narcotic use.

Continuous versus single shot brachial plexus block and their relationship to discharge barriers and length of stay

BACKGROUND

Brachial plexus block has been associated with improved pain control and decreased length of stay in patients undergoing upper extremity arthroplasty. Continuous delivery is associated with a shorter length of stay; however, comparisons to single-shot delivery in this setting are scarce. As the paradigm shifts to outpatient arthroplasty in the era of bundled payments, there exists a strong impetus to identify the most effective mode of analgesia associated with the least risk to patients.

METHODS

This is a retrospective review of 697 patients undergoing upper extremity arthroplasty comparing the rate of complications and incidence of potential barriers to discharge and length of stay of patients receiving continuous vs. single-shot perineural brachial plexus block.

RESULTS

No difference was observed in the complication rate between indwelling (n = 63 [12%]) and single-shot groups (n = 30 [17%]; P = .137). The majority of complications were pulmonary, 72% attributable to oxygen desaturation. The indwelling catheter group had 1.61 times higher odds (95% confidence interval, 1.07-2.42; P = .023) of exhibiting any potential barrier to discharge and exhibited a longer length of stay (P = .002).

CONCLUSION

There was no demonstrated disparity in the rate of complications associated with single-shot vs. continuous brachial plexus block. However, the continuous indwelling catheter was associated with an increased incidence of potential barriers to discharge and an increased length of stay compared with patients receiving single-shot regional anesthesia.

Blind suprascapular and axillary nerve block for post-operative pain in arthroscopic rotator cuff surgery

PURPOSE

The goal of the study was to evaluate the efficacy of additional axillary nerve block (ANB) with suprascapular nerve block (SSNB) and patient-controlled anaesthesia (PCA) with no device assistance after arthroscopic rotator cuff repair. The hypothesis is that patients with intravenous (IV) PCA and the blockade of the two main nerves (SSNB + ANB) experienced lesser pain than patients with IV PCA or IV PCA + SSNB.

METHODS

The 114 patients undergoing arthroscopic rotator cuff repair were allocated randomly to three groups as follows: group I, intravenous PCA pumps (only PCA); group II, IV PCA + SSNB using a blind technique (PCA + SSNB); and group III, IV PCA + SSNB + ANB using a blind technique (PCA + SSNB + ANB). Pain visual analogue scale (VAS) scores were evaluated at 1, 6, 12, 24, 36, and 48 post-operative hours. Furthermore, the degree of pain was compared according to cuff tear size.

RESULTS

The pain VAS score of group III was lower than that of the other two groups and was significantly lower at post-operative hours 1, 6, and 12. In addition, the larger cuff tear tended to be indicative of greater pain. However, all groups experienced rebound pain.

CONCLUSION

PCA + SSNB + ANB using a blind technique is a better pain control method than PCA + SSNB and only PCA during the initial 12 post-operative hours. PCA + SSNB + ANB is a cost-effective, time-saving, and easily performed method for post-operative pain control as an axis of multimodal pain control strategy.

LEVEL OF EVIDENCE

II.

Comparison of Interscalene Brachial Plexus Block Performed With and Without Steroids

This prospective comparative clinical study was performed to evaluate the effect of triamcinolone when added to bupivacaine during brachial plexus blockade in patients undergoing shoulder surgery. Interscalene brachial plexus blocks were performed on 910 patients before shoulder surgery. Of the patients, 574 were randomly allocated to receive steroids added to the injected local anesthetic and 336 patients received local anesthetic without steroids. All patients were followed prospectively to evaluate the rate of successful anesthesia, duration of anesthesia, side effects of the block, adverse events, and persistent neurologic complications associated with interscalene brachial plexus block. Patients who received steroids had statistically longer pain relief than those who did not receive steroids (P<.001). No difference was found in adverse events, complications, or side effects. Compared with blocks performed without steroids, a statistically longer duration of block analgesia occurred with the addition of steroids to the local anesthetic solution during brachial plexus blockade. Rates of side effects, adverse events, and persistent neurologic complications were similar between the groups. [Orthopedics. 2016; 39(6):e1100-e1103.].

Suprascapular Nerve Block Versus Interscalene Block as Analgesia After Arthroscopic Rotator Cuff Repair: A Randomized Controlled Noninferiority Trial

PURPOSE

To compare the efficacy of suprascapular nerve block (SSB) and interscalene block (ISB) as postoperative analgesia within the first 24 hours after arthroscopic supraspinatus and/or infraspinatus tendon repair.

METHODS

A single-blind, randomized controlled study was performed between 2013 and 2014. The inclusion criteria were arthroscopic supraspinatus and/or infraspinatus tendon repair confirmed intraoperatively, with or without associated procedures, and informed consent. The exclusion criteria were a previously operated shoulder, repair of the subscapularis tendon, and an allergy to local anesthetics. ISB was performed under ultrasound guidance by an anesthesiologist, whereas SSB was performed based on specific anatomic landmarks by a surgeon. The primary evaluation criterion was mean shoulder pain score during the first postoperative 24 hours assessed on a visual analog scale by the patient. The secondary criteria were complications of locoregional anesthesia, the use of analgesics in the recovery room (the first 2 hours) until postoperative day 7, and pain (visual analog scale) during the first week. Forty-four patients were needed for this noninferiority study. An institutional review board approved the study.

RESULTS

Seventy-four patients were randomized, and 59 met the intraoperative inclusion criteria. Six patients were excluded (1 for pneumothorax after ISB, 1 for unsuccessful SSB, and 4 for incomplete questionnaires). None of the patients were lost to follow-up. There was no significant difference between the SSB and ISB groups in mean pain score for the first 24 hours (P = .92) or the first 7 days (P = .05). However, there was significantly less pain in the ISB group in the recovery room (P = .01). Consumption of analgesics was comparable between the groups, but the SSB group took significantly more morphine in the recovery room.

CONCLUSIONS

In this prospective, randomized controlled study, SSB was as effective as ISB for mean pain control within the first 24 hours but ISB was more effective in relieving pain in the recovery room after arthroscopic supraspinatus and/or infraspinatus tendon repair.

LEVEL OF EVIDENCE

Level I, therapeutic, randomized controlled study.

Which outcomes related to regional anesthesia are most important for orthopedic surgery patients?

An increasing body of evidence supports the benefits of regional anesthesia in orthopedic surgery. Compared with systemic anesthetic and analgesic approaches, these benefits include more focused and sustained pain control, less systemic side effects, improved patient comfort, earlier mobilization and hospital discharge, lower rates of advanced service requirements, and lower perioperative morbidity and mortality. However, there is discussion about the various outcomes as judged by patients and heath care practitioners. This article recapitulates the literature and presents an overview of endpoints.

Shoulder surgeons' perceptions of interscalene nerve blocks and a review of complications rates in the literature

BACKGROUND

Interscalene nerve blocks (ISBs) have been shown to be an effective option for regional anesthesia in shoulder surgery. Our study presents survey results of shoulder surgeons' perceptions of ISBs and a literature summary of complications rates with ISB use.

METHODS

A survey addressing demographics, preferences, treatment patterns, risks/benefits, and patient recommendations regarding the use of ISBs was created. Respondents were also asked whether they would elect an ISB if personally undergoing shoulder surgery, and results of other questions were stratified based on this personal preference. The survey was administered electronically to all members of the American Shoulder and Elbow Surgeons. A literature review of ISB-related complication rates was compiled from 13 studies of shoulder surgery using ISB.

RESULTS

Of all respondents, 58.7% would elect a single-shot ISB, 15.0% would elect a continuous catheter, and 26.3% would not elect the use of an ISB if undergoing shoulder surgery. Respondents from a university hospital were 1.44 times more likely to elect any ISB than respondents from a non-university hospital. Improved post-operative pain control was considered the greatest benefit, whereas persistent neuropathy was considered the greatest risk of ISB use. Of the respondents, 76.1% would recommend use of ISB to their patients undergoing shoulder surgery. Our literature review yielded 13 applicable studies that utilized a total of 6243 ISBs, with data resulting in a 0.35% major complication rate and an 11.32% minor complication rate in patients.

CONCLUSION

The majority of shoulder surgeons surveyed in our study would elect to have a single-shot interscalene nerve block if undergoing shoulder surgery themselves, indicating that ISB use is considered a safe and effective anesthetic option among shoulder surgeon specialists.

Perioperative care for the older outpatient undergoing ambulatory surgery

As the number of ambulatory surgery procedures continues to grow in an aging global society, the implementation of evidence-based perioperative care programs for the elderly will assume increased importance. Given the recent advances in anesthesia, surgery, and monitoring technology, the ambulatory setting offers potential advantages for elderly patients undergoing elective surgery. In this review article we summarize the physiologic and pharmacologic effects of aging and their influence on anesthetic drugs, the important considerations in the preoperative evaluation of elderly outpatients with coexisting diseases, the advantages and disadvantages of different anesthetic techniques on a procedural-specific basis, and offer recommendations regarding the management of common postoperative side effects (including delirium and cognitive dysfunction, fatigue, dizziness, pain, and gastrointestinal dysfunction) after ambulatory surgery. We conclude with a discussion of future challenges related to the growth of ambulatory surgery practice in this segment of our surgical population. When information specifically for the elderly population was not available in the peer-reviewed literature, we drew from relevant information in other ambulatory surgery populations.

Effects of interscalene brachial plexus block to intra-operative hemodynamics and postoperative pain for arthroscopic shoulder surgery

Background

Although arthroscopic shoulder surgery is less invasive and painful than open shoulder surgery, it can often cause intra-operative hemodynamic instability and severe post-operative pain. This study was conducted to investigate the efficacy of the interscalene brachial plexus block (IBPB) on intra-operative hemodynamic changes and post-operative pain during arthroscopic shoulder surgery.

Methods

After institutional review board approval, 50 consecutive patients that had undergone arthroscopic shoulder surgery under general anesthesia were randomly assigned to one of two groups to evaluate intra-operative hemodynamic changes and post-operative pain control. Group 1 patients received an IBPB with 10 ml of normal saline guided by a nerve stimulator before induction, and Group 2 patients received 10 ml of 0.5% ropivacaine hydrochloride with the same technique. The heart rate and systolic and diastolic blood pressures were recorded before the incision and 1, 3, 5, 10, and 20 minutes after the incision. Pre-operative and post-operative pain was evaluated with a visual analog scale 1, 3, 6, 12, and 24 hours after surgery. The patients were given tramadol as a rescue medication option. The total volume of tramadol that was injected was also evaluated over the same intervals.

Results

Group 2 showed significantly lower systolic and diastolic blood pressures and heart rates intra-operatively compared to Group 1 (P < 0.05). The visual analog scale pain scores, except at 24 hours after surgery, were significantly lower in Group 2 (P < 0.05). The total tramadol consumption significantly reduced in Group 2 (P < 0.05).

Conclusions

IBPB effectively controlled the hemodynamic changes that occurred during arthroscopic shoulder surgery as well as post-operative pain.

Pathomechanisms and complications related to patient positioning and anesthesia during shoulder arthroscopy

The lateral decubitus and beach-chair positions each offer unique benefits to the shoulder surgeon with respect to visualization, efficiency, and ease during arthroscopic shoulder procedures. The purpose of this article was to comprehensively review the reports and studies documenting independent and dependent complications related to patient positioning and anesthesia during arthroscopic shoulder surgery. The lateral decubitus position has been associated with the potential for peripheral neurapraxia, brachial plexopathy, direct nerve injury, and airway compromise. The beach-chair position has been associated with cervical neurapraxia, pneumothorax, and the potential for end-organ hypoperfusion injuries (when deliberate hypotension is used). Potentially concerning are hypotensive bradycardic events, which may be relatively common in association with the use of epinephrine-containing interscalene anesthetics in beach chair-positioned patients. Irrigant complications (fluid spread, ventricular tachycardia) are avoidable risks not unique to either specific position. Although minor transient anesthetic- and position-related complications (neurapraxia, hypotension) may occur in as many 10% to 30% of patients, major complications such as end-organ damage or permanent impairments are exceedingly rare. Regardless of position, complications are almost uniformly avoidable if surgeon and anesthetist exercise care and prudent attention to position and anesthetic choices. The purpose of this article is to review the potential for position- and anesthesia-related complications and acquaint the shoulder surgeon with the proposed pathophysiologic mechanisms that can lead to them.

A prospective analysis of interscalene brachial plexus blocks performed under general anesthesia

BACKGROUND

The purpose of this prospective study was to assess the safety and efficacy of interscalene brachial plexus block anesthesia when performed on patients who were anesthetized with a general anesthetic prior to the performance of the block.

METHODS

Patients were assessed postoperatively through surveys, interviews, and physical examinations to document block success, duration of anesthesia, block side effects, and persistent neurological complications. Nine-hundred fifty-one patients were available for the analysis.

RESULTS

The overall block success rate was 97% and the mean duration of anesthesia provided by the blocks was 23.9 hours. Immediate postoperative block side effects occurred in 16% (142 of 910), persistent neurological complications occurred in 4.4% (40 of 910) of patients, and long-term neurologic complications occurred in 0.8% (8 of 910).

CONCLUSION

Our study results suggest that the rates of success and complications associated with the performance of interscalene block regional anesthesia performed after induction of general anesthesia are similar to the results demonstrated in prior studies in which brachial plexus block was performed on nonanesthetized patients. Although significant complications were not common, this procedure is not without risk and can result in long-term neurologic complications.

Prolonged Dyspnea after Interscalene Block: Attributed to Undiagnosed Addison's Disease and Myasthenia Gravis

This report describes a patient who had a series of daily interscalene nerve blocks to treat pain following a shoulder manipulation for postsurgical stiffness. She experienced acute respiratory compromise that persisted for many weeks. All typical and unusual causes of these symptoms were ruled out. Her treating pulmonologist theorized that the ipsilateral carotid body had been injured. However, it was subsequently determined that the constellation of symptoms and their prolonged duration were best explained by a poor stress response from Addison's disease coupled with exacerbation of early onset myasthenia gravis. This patient's case is not a typical reaction to interscalene nerve blocks, and thus preoperative testing would not be recommended for myasthenia gravis or Addison's disease without underlying suspicion. We describe this report to inform physicians to consider a workup for these diagnoses if a typical workup rules out all usual causes of complications from an interscalene block.

Interscalene block for shoulder surgery in physician-owned community ambulatory surgery centers

PURPOSE

To retrospectively report on a series of patients who had interscalene block regional anesthesia performed for outpatient open and arthroscopic shoulder surgical procedures in a community-based ambulatory surgery center setting.

METHODS

We reviewed the cases of 1,945 patients who had interscalene block regional anesthesia performed during an 8-year period.

RESULTS

The complication rate was 0.63%, with all complications occurring in the immediate postoperative period, none of which were permanent.

CONCLUSIONS

With an expert, experienced anesthesia team, the interscalene block can be a safe method (temporary complication rate, 0.63%) of intraoperative anesthesia and perioperative analgesia for outpatient open and arthroscopic shoulder surgery in physician-owned ambulatory surgery centers.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Superficial cervical plexus neuropathy after single-injection interscalene brachial plexus block

BACKGROUND

Interscalene brachial plexus block (ISB) using the modified lateral approach provides a well-established method of anesthesia and analgesia for patients undergoing shoulder surgery. Considering the neural anatomy at the site of injection, the superficial cervical plexus may be at risk of injury. We evaluated the incidence and characteristics of superficial cervical plexus neuropathy.

METHODS

During a 1-yr period, 273 consecutive patients requiring single-injection ISB for shoulder or proximal arm surgery were studied. Patients were examined for symptoms compatible with superficial cervical plexus injury before surgery, 24 h postoperatively, and contacted by telephone 31 days after surgery. Symptomatic patients received an additional phone call 6 mo after surgery.

RESULTS

Twenty-four hours after shoulder surgery, 21 patients (7.7%) showed symptoms consistent with superficial cervical plexus neuropathy. Symptoms consisted of hypesthesia in 1-4 cutaneous branches of the cervical plexus. Five patients (1.8%) reported symptoms that lasted for >31 days. All symptoms had entirely resolved after 6 mo.

CONCLUSIONS

Superficial cervical plexus neuropathy is not uncommon after ISB using the modified lateral approach and the possibility should be discussed with patients preprocedurally.

Clinical utility of low-volume ultrasound-guided interscalene blockade: contraindications reconsidered

OBJECTIVE

The purpose of this series is to describe cases in which ultrasound guidance was used to allow patients to receive the benefits of regional anesthesia while safely circumventing traditional contraindications to interscalene blockade (ISB).

METHODS

Targeted low-volume ISB was performed in 3 patients in whom this procedure would typically be contraindicated because of phrenic nerve blockade or risk of local anesthetic toxicity. A patient with severe respiratory dysfunction, a patient undergoing bilateral shoulder surgery, and a patient requiring awake fiberoptic intubation underwent low-volume ultrasound-guided ISB. The ultrasound technique involved the use a low local anesthetic volume, anatomic identification of the brachial plexus trunk, needle placement opposite the phrenic nerve position, and control over local anesthetic spread.

RESULTS

In both patients in whom diaphragmatic paralysis was a concern, postoperative respiratory parameters indicated successful regional analgesia without evidence of phrenic nerve blockade. In the patient requiring an additional regional anesthetic procedure, ISB was performed with a local anesthetic volume low enough to avoid exceeding toxic safety thresholds.

CONCLUSIONS

Although further studies are warranted, we report on 3 cases in which ultrasound guidance was used to allow patients to receive the benefits of regional anesthesia while safely avoiding standard contraindications to ISB. Ultrasound technology may allow providers to perform low-volume brachial plexus blockade while avoiding issues related to phrenic nerve blockade and systemic local anesthetic toxicity.

Low interscalene block provides reliable anesthesia for surgery at or about the elbow

STUDY OBJECTIVE

To determine whether interscalene brachial plexus block (ISB) provides adequate anesthesia for surgery on or about the elbow.

STUDY DESIGN

Case series.

SETTING

Operating room of an academic teaching hospital.

PATIENTS

78 patients scheduled for elective elbow surgery.

INTERVENTIONS

All patients received an ISB using a low approach technique. A stimulating needle was inserted in the interscalene groove two cm above the clavicle. A volume of 35-45 mL of mepivacaine 1.5% or ropivacaine 0.5% was administered after obtaining a motor response of any component of the brachial plexus with a current intensity of 0.2-0.4 mA (0.1 msec).

MEASUREMENTS

Block success rate, defined as the ability to complete surgery without use of intraoperative opioids or general anesthesia, was assessed. Verbal rating scores for pain (0 = no pain, 10 = worst pain imaginable) were obtained in the recovery room.

MAIN RESULTS

Low ISB resulted in successful surgical anesthesia in 75 (96%) of the study patients. Verbal rating scores were low (0-2) for all patients postoperatively.

CONCLUSIONS

The low interscalene block can be used to provide surgical anesthesia in the majority of patients having surgery on or about the elbow.

Pain pump use after shoulder arthroscopy as a cause of glenohumeral chondrolysis

Shoulder arthroscopy has become a routine outpatient surgery. Pain control is a limiting factor for patient discharge after surgery, and several modalities are used to provide continued analgesia postoperatively. Regional anesthetic blocks and shoulder pain pumps are common methods to provide short-term pain control. Shoulder pain pumps can be used either in the subacromial space or within the glenohumeral joint. Several clinical studies suggested--which was confirmed by a bovine and rabbit cartilage study--that there is significant chondrotoxicity from bupivacaine, a local anesthetic commonly used in pain pumps. Postarthroscopic glenohumeral chondrolysis is a noninfectious entity associated with factors including use of radiofrequency thermal instruments and intra-articular pain pumps that administer bupivacaine, but there have been no cases reported with subacromial pain pump placement. Treatment options are difficult in a young patient with postarthroscopic glenohumeral chondrolysis, and understanding the literature with regard to risk factors is paramount to counseling patients and preventing this devastating complication.

Regional anesthesia at home

PURPOSE OF REVIEW

To review the recently published peer-reviewed literature involving regional anesthesia and analgesia in patients at home.

RECENT FINDINGS

The potential benefits and risks of regional anesthesia and analgesia at home are pertinent queries, and increased data regarding these topics are rapidly becoming available. Of particular interest is the use of continuous peripheral nerve blocks at home and their potential effect upon hospitalization duration and recovery profile.

SUMMARY

Advantages of regional techniques include site-specific anesthesia and decreased postoperative opioid use. For shoulder surgeries, the interscalene block provides effective analgesia with minimal complications, whereas the impact and risks of intraarticular injections remain unclear. Perineural catheters are an analgesic option that offer improved pain relief among other benefits. They are now being used at home in both adult and pediatric populations.

Subacromial pain pump use with arthroscopic shoulder surgery: a short-term prospective study of complications in 583 patients

Pain pumps containing local anesthetics, with or without opioids, can be used for perioperative analgesia after arthroscopic shoulder surgery to reduce pain. Although several smaller studies have demonstrated the analgesic properties, no large series to date has reported the short-term complication rate of subacromial pain pumps. We prospectively studied (2005 to 2007) 583 patients who underwent arthroscopic shoulder surgery at a single outpatient surgery center and had intraoperative placement of a pain pump catheter into the subacromial space. Patients had at least 1 month of follow-up. No patient received perioperative brachial plexus regional anesthesia. There were no cases of infection, internal catheter breakage, pump failure, or hospital admission for pain control. The only complication was external catheter breakage that occurred when a patient attempted to remove the pump without removing the tape fastening the catheter at the skin. Subacromial pain pumps used for arthroscopic shoulder procedures are safe in the short-term.

The relationship between current intensity for nerve stimulation and success of peripheral nerve blocks performed in pediatric patients under general anesthesia

BACKGROUND

We evaluated the relationship between the lowest current amperage used to obtain a motor response, the success rate and the incidence of neurological complications with peripheral nerve blocks (PNB) in pediatric patients under general anesthesia.

METHODS

We reviewed the regional anesthesia database at The Children's Hospital of Philadelphia and included all pediatric patients who received a single-injection PNB under general anesthesia with the aid of a peripheral nerve stimulator between October 2002 and July 2006. Data analyzed included age, sex, type of block, stimulation threshold, presence of sensory and motor blockade, and neurological complications.

RESULTS

Six-hundred sixty patients received a PNB during the study period. The average age of the patients was 13.8 yr (range = 2-18 yr). All the blocks were performed using a current ranging between 0.2 and 1 (median = 0.5 mA, interquartile range: 0.45-0.55 mA). The overall success rate was 96%. There was no difference in success rate between blocks performed using a stimulation threshold of < or =0.5 or >0.5 mA (96.3% vs 95.9%; P = 0.793). There was no correlation between the success rate and sex, type of block performed or intensity of current used. Two patients reported prolonged nerve blockade of the great toe and dorsum of the foot after a sciatic nerve block, which lasted for 72 h. No long-term sequelae were noted in our patients.

CONCLUSION

In this study, a similar PNB success rate was observed with both a low (*0.5 mA) and a high stimulation threshold (>0.5 mA). Therefore, it may not be necessary to perform needle manipulations to achieve a low stimulation threshold (< or =0.5 mA), as this may increase the risk of intraneural injection.