Ultrasound-guided peripheral nerve blockade

Liposomal Bupivacaine for Peripheral Nerve Blockade: A Randomized, Controlled, Crossover, Triple-blinded Pharmacodynamic Study in Volunteers

BACKGROUND

Little is known about the pharmacodynamic characteristics of liposomal bupivacaine. Hypothesizing that they would not identify pharmacodynamic differences from plain bupivacaine during the initial period after administration, but would find better long-term pharmacodynamic characteristics, the authors designed a randomized, controlled, triple-blinded, single-center study in volunteers.

METHODS

Volunteers aged 18 to 55 yr (body mass index, 18 to 35 kg/m2) received two ulnar nerve blocks under ultrasound guidance. Using a crossover design with a washout phase of 36 days or more, one block was performed with liposomal and one with plain bupivacaine. Which came first was determined by randomization. Sensory data were collected by pinprick testing and motor data by thumb adduction, either way in comparison with the contralateral arm. Endpoints included success, time to onset, and duration of blockade. Residual efficacy was assessed by the volunteers keeping a diary. Statistical analysis included Wilcoxon signed-rank and exact McNemar's tests, as well as a generalized estimation equation model.

RESULTS

Successful sensory blockade was noted in 8 of 25 volunteers (32%) after liposomal and in 25 of 25 (100%) after plain bupivacaine (P < 0.0001). Significant differences emerged for time to onset, defined as 0% response to pinpricking in four of five hypothenar supply areas (P < 0.0001), and for time from onset to 80% or 20% in one of five areas (P < 0.001; P < 0.001). Carryover effects due to the randomized sequencing were unlikely (estimate, -0.6286; sequence effect, 0.8772; P = 0.474). Self-assessment greater than 3.5 days did reveal, for liposomal bupivacaine only, intermittent but unpredictable episodes of residual sensory blockade.

CONCLUSIONS

The results show that liposomal bupivacaine is not a suitable "sole" drug for intraoperative regional anesthesia. Findings of its limited long-term efficacy add to existing evidence that a moderate effect, at best, should be expected on postoperative pain therapy.

EDITOR’S PERSPECTIVE

The safety and efficacy of ultrasound-guided erector spinae plane block in postoperative analgesic of PCNL: A systematic review and meta-analysis

BACKGROUND

The patients received percutaneous nephrolithotomy (PCNL) with severe postoperative pain and discomfort. The erector spinae plane block (ESPB), as a new anesthesia method of plane block, has a positive effect on postoperative analgesia. But evidence of ESPB in PCNL is still lacking. The objective of this study was to systematically analyze the postoperative analgesic effect of ESPB in patients receiving PCNL.

METHODS

The literature searching was conducted in PubMed, EMBASE, Cochrane Library and Clinical Trial Database (clinicaltrials.gov). Two independent researchers screened the included studies and extracted data. Meta-analysis was conducted by using the random-effect model with 95% confidence intervals. Chi-squared test with a significance level of 0.1 was utilized to evaluate the heterogeneity of included studies. The subgroup analysis and meta-regression analysis were conducted in studies with high heterogeneity. The publication bias was assessed based on whether there were discrepancies between prospective trial registration and reported protocols.

RESULTS

There were 8 studies involving 456 patients assessing the efficacy of ESPB in reducing postoperative pain score of PCNL compared with no block or other blocks, such as subcutaneous infiltration, general anesthesia or TPVB intrathecal morphine. ESPB was a significantly effective and safe anesthesia method, which not only improved postoperative pain response (MD -1.76; 95% CI -2.57 to -0.94; I 2 = 85%; p<0.01), but also reduced analgesic consumption (MD -16.92; 95% CI -26.25 to -7.59; I 2 = 92.2%; p<0.01) and prolonged the time of first request for postoperative analgesia (MD 93.27; 95% CI 35.79 to 150.75; I 2 = 85.3%; p = 0.001) in patients receiving PCNL without significant postoperative complications (MD 0.80; 95% CI 0.31 to 2.03; I 2 = 0%; p = 0.404).

CONCLUSIONS

Compared with no block or other blocks, the ESPB was a safe and effective anesthesia for patients receiving PCNL.

Examining the impact perceptual learning artificial-intelligence-based on the incidence of paresthesia when performing the ultrasound-guided popliteal sciatic block: simulation-based randomized study

OBJECTIVE

To explore the impact of artificial-intelligence perceptual learning when performing the ultrasound-guided popliteal sciatic block.

METHODS

This simulation-based randomized study enrolled residents who underwent ultrasound-guided sciatic nerve block training at the Department of Anesthesiology of Beijing Jishuitan Hospital between January 2022 and February 2022. Residents were randomly divided into a traditional teaching group and an AI teaching group. All residents attended the same nerve block theory courses, while those in the AI teaching group participated in training course using an AI-assisted nerve identification system based on a convolutional neural network instead of traditional training.

RESULTS

A total of 40 residents were included. The complication rates of paresthesia during puncture in the first month of clinical sciatic nerve block practice after training were significantly lower in the AI teaching group than in the traditional teaching group [11 (4.12%) vs. 36 (14.06%), P = 0.000093]. The rates of paresthesia/pain during injection were significantly lower in the AI teaching group than in the traditional teaching group [6 (2.25%) vs. 17 (6.64%), P = 0.025]. The Assessment Checklist for Ultrasound-Guided Regional Anesthesia (32 ± 3.8 vs. 29.4 ± 3.9, P = 0.001) and nerve block self-rating scores (7.53 ± 1.62 vs. 6.49 ± 1.85, P < 0.001) were significantly higher in the AI teaching group than in the traditional teaching group. There were no significant differences in the remaining indicators.

CONCLUSION

The inclusion of an AI-assisted nerve identification system based on convolutional neural network as part of the training program for ultrasound-guided sciatic nerve block via the popliteal approach may reduce the incidence of nerve paresthesia and this might be related to improved perceptual learning.

CLINICAL TRIAL

CHiCTR2200055115 , registered on 1/ January /2022.

Ultrasound-Guided Erector Spinae Plane Block in Thoracolumbar Spinal Surgery: A Systematic Review and Meta-Analysis

Introduction

Neurosurgical spinal surgeries such as micro- discectomy and complex fusion surgeries remain the leading causes of disability-adjusted life-year. Major spinal surgeries often result in severe postprocedural pain due to massive dissection of the underlying tissues. While opioids offer effective pain control, they frequently lead to side effects, such as post-operative nausea and vomiting, pruritus, constipation, and respiratory depression. ESPB was successfully used in spinal surgery as a component of a multimodal analgesic regimen and it eliminated the requirements for opioids. The primary purpose of this systematic review and meta-analysis was to compare post-operative opioid consumption between ESPB and placebo.

Methods

To conduct this systematic review, we used the “Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)” guidelines. We conducted a search for relevant articles available in the following databases: Google Scholar, PubMed, and the Cochrane Library published up to March 2022.

Results

The total morphine consumption within 24 h after surgery was lower in the ESPB group, the mean difference (in mg of morphine) with 95% CI is −9.27 (−11.63, −6.91). The pain intensity (0–10) at rest measured 24 h after surgery was lower in the ESPB group, the MD with 95% CI is −0.47 (−0.77, −0.17). The pain intensity during movement measured 24 h after surgery was lower in the ESPB group, the MD with 95% CI is −0.73 (−1.00, −0.47). Post-operative nausea and vomiting were significantly lower in the ESPB group, the risk ratio with 95% CI is 0.32 (0.19, 0.53).

Conclusion

Ultrasound-guided ESPB was superior to placebo in reducing post-operative opioid consumption, pain intensity, post-operative nausea and vomiting, and prolonging the time to first rescue analgesia. There were no ESPB-related serious complications reported.

Erector Spinae Plane Block in Abdominal Surgery: A Meta-Analysis

Background

Abdominal surgery is one of the most definitive and mainstay treatment options for abdominal pathologies in clinical practice. Acute postoperative pain is a major challenge in the postoperative period. Although opioids are commonly used for analgesia after major abdominal surgeries, they can lead to side effects, such as nausea and vomiting, constipation, pruritus, and life-threatening respiratory depression. Regional anesthetic techniques are commonly used to prevent or minimize these side effects. The objective of this meta-analysis is to assess the effectiveness of erector spinae plane block (ESPB) and standard medical (no block) pain management after major abdominal surgeries.

Methods

We searched for articles reporting the results of randomized controlled trials on ESPB and no block in pain control published before May 2021.

Results

The systematic search initially yielded 56 publications, 49 articles were excluded, and seven randomized clinical trials were included and analyzed. We extracted the data on postoperative opioid consumption, the efficacy of pain relief, time to the first opioid demand, and the rate of postoperative complications in the ESPB group and no block group.

Conclusions

Opioid requirement and time to first analgesic request were significantly reduced in the ultrasound-guided ESPB group, but pain scores, nausea, and vomiting did not differ significantly after pooling the results of the block and no block studies. There were no reports on serious complications related to ESPB.

A Survey of Regional Anesthesia Use in Greece and the Impact of a Structured Regional Anesthesia Course on Regional Techniques Knowledge and Practice

Background: Due to the growing interest in regional anesthesia (RA) techniques and the realization of the need for formalized education in them, the Greek Chapter of the European Society of Regional Anesthesia and Pain Therapy (ESRA-Hellas) has established a structured hands-on training course held annually since 2009, which is quite popular in the community of Greek anesthesiologists. The aim of the current survey was twofold: first, to provide an overview of the current practice of RA in Greece; secondly, to evaluate the effect the aforementioned training course has on participants’ knowledge and attitude towards RA. Methods: An electronic questionnaire was uploaded on SurveyMonkey and a link giving access to the questionnaire was forwarded via email to a mailing list of 825 practicing Greek anesthesiologists held in the electronic database of ESRA Hellas. The survey was totally anonymous and no identifying information was collected throughout. It contained questions relating to the anesthesiologists’ demographic characteristics, their RA practice, and information pertaining to the RA training course. Results: A total of 424 fully completed questionnaires were received, representing an overall response rate of 51.4%. Attendants of the course are more familiar than non-attendants with the performance of peripheral nerve blocks with neurostimulation and/or ultrasound guidance (p < 0.001). Attendants are also less likely to practice exclusively general anesthesia, more likely to use peripheral blocks for lower limb surgery, and more likely to consider taking the European Diploma of RA in comparison to non-attendants (p < 0.001, p = 0.018 and p = 0.002, respectively). Both cohorts consider the course of value and agree that the main reason to use regional techniques is to ensure optimal postoperative analgesia, while the main hindrance to RA practice is the lack of relevant education in the techniques, especially those under ultrasound guidance. Regarding improvement of the course, most participants suggested devoting ampler time in hands-on ultrasound practice and application. Conclusions: Greek anesthesiologists seek educational activities in the field of RA and the course seems to fulfil the majority of attendants’ expectations. There will be further effort by the organizers to improve weaknesses of the current course and undertake further educational initiatives in the field of RA according to international recommendations.

Novel Regional Nerve Blocks in Clinical Practice: Evolving Techniques for Pain Management

This review examines the use of novel US-guided nerve blocks in clinical practice. Erector spinae block is a regional anesthesia technique doing by injecting a local anesthetic among the erector spinae muscle group and transverse processes. The phrenic nerve is a branch of the cervical plexus, arising from the anterior rami of cervical nerves C3, C4, and C5. The quadratus lumborum muscle is located along the posterior abdominal wall. It originates from the transverse process of the L5 vertebral body, the iliolumbar ligament, and the iliac crest. US-guided peripheral nerve procedures have a considerable scope of use, including treating headaches and hiccups to abdominal surgical pain, cesarean sections, musculoskeletal pathologies. These nerve blocks have been an effective addition to clinical anesthesia practice. The use of peripheral nerve blocks has improved postoperative pain, lessened the use of opioids and their potential side effects, and decreased the incidence of sleep disturbance in patients. More research should be done to further delineate the potential benefits of these blocks.

Erector spinae plane block in acute interventional pain management: a systematic review

Erector Spinae Plane Block (ESPB) was described by Forero in 2016. ESPB is currently widely used in acute postoperative pain management. The benefits of ESPB include simplicity and efficacy in various surgeries. The aim of this review was to conduct a comprehensive overview of available evidence on erector spinae plane block in clinical practice. We included randomized controlled trials and systematic reviews reporting the ESPB in human subjects. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Twenty-one articles including five systematic reviews and 16 randomized controlled trials were included and analyzed. ESPB appears to be an effective, safe, and simple method for acute pain management in cardiac, thoracic, and abdominal surgery. The incidence of side effects has been reported to be rare. A critical issue is to make sure that new evidence is not just of the highest quality, in form of well powered and designed randomized controlled trials but also including a standardized and homogeneous set of indicators that permit to assess the comparative effectiveness of the application of ESPB in acute interventional pain management.

The Efficacy and Safety of Transversus Abdominis Plane Blocks After Open Cholecystectomy in Low- and Middle-Income Countries

BACKGROUND

Postoperative pain management is challenging in low- and middle-income countries (LMICs). This study assesses the safety and efficacy of transversus abdominis plane (TAP) blocks as an adjunct for postoperative pain control after an open cholecystectomy in LMICs during short-term surgical missions (STSMs). TAP block is a regional anesthesia technique that has been shown to be effective in providing supplementary analgesia to the anterolateral wall post abdominal surgery.

METHODS

A retrospective chart review of patients undergoing open cholecystectomy during STSMs was performed. STSMs took place in Guatemala, the Philippines, and Peru from 2009 to 2019. Measured outcomes including pain scores, presence of postoperative nausea or vomiting, and opioid consumption were compared between TAP block and non-TAP block groups.

RESULTS

Of the 48 patients analyzed, 28 underwent TAP block (58%). Non-TAP block patients received, on average, 8 mg of oral morphine equivalents more than the TAP patients (P = 0.035). No significant difference was noted in pain scores, which were taken immediately after surgery, 2 h after surgery, and at multiple times between these time points to calculate an average. Of the patients who received a TAP block, 11% reported nausea or vomiting compared with 45% in the standard group (P < 0.01). There were no reported procedure-related complications.

CONCLUSIONS

TAP blocks are safe and effective adjuncts for postoperative pain management on STSMs to LMICs. Additional studies are needed to investigate the potential advantages and disadvantages of more widespread use of TAP blocks in LMICs.

Anterior approach of abdominal field block at linea semilunaris: A surgically assisted novel technique for postoperative analgesia in cesarean section

Context

Post Caesarean pain is described as moderate to severe. Although advances in the new analgesics techniques, no current standard exists for optimizing and managing. Taking into consideration of acute post Caesarean pain, this novel technique of surgically assisted anterior abdominal field block at linea semilunaris have proved considerable analgesic potential along with multimodal analgesia.

Aims

Although advances have been made in the understanding of the pathophysiology and in the development of new analgesics, patients still suffer from moderate-to-severe post-Cesarean pain. Taking into consideration the consequences of pain, this anterior approach to abdominal field block technique was performed to minimize acute pain experienced during post-Cesarean section.

Settings and Design

Prospective observational study design.

Materials and Methods

In the present study, a total of 120 parturients undergoing cesarean section (CS), after closure of uterine incision were included. We intraoperatively, under all asepsis, performed surgically assisted abdominal field block at linea semilunaris, by bilaterally injecting 20 mL 0.25% bupivacaine on each side, in addition to standard analgesic 100 mg diclofenac suppository. Each patient was assessed at 0, 4, 8, 12, and 24 h after surgery, by an independent observer for pain using NRS 0-10 and the time of the first demand for analgesic diclofenac paracetamol and its side effects.

Statistical Analysis Used

The entire data is statistically analyzed using Statistical Package for Social Sciences (SPSS ver. 21.0, IBM Corporation, USA) for MS Windows. The categorical variables were compared using Wilcoxon's signed-rank test.

Results

Of the total 120 patients, it is worth noting that none of the patients had severe or worst pain. The percentage of patients who did not require analgesia were (96.7%) at 4 h, (81.7%) at 8 h, (77.5%) at 12 h, and (90.8%) at 24 h. The mean analgesic consumption of paracetamol diclofenac on 4, 8, 12, 16, and 24 h after CS was significantly less. No patient required opioid supplementation. Patient satisfaction was high and was early ambulated.

Conclusions

There is considerable potential for anterior approach abdominal field block, (linea semilunaris block) to comprise an effective component of a multimodal regimen for post-Cesarean section analgesia and is easy to perform within limited resources.

Comparison of ultrasound-guided transversus abdominis plane block, quadratus lumborum block, and caudal epidural block for perioperative analgesia in pediatric lower abdominal surgery

Background/aim

Despite different regional anesthesia techniques used to provide intraoperative and postoperative analgesia in pediatric patients, the analgesic effectiveness of peripheral nerve blockades with minimal side effect profiles have not yet been fully determined. We aimed to compare the efficacy of ultrasound-guided transversus abdominis plane (TAP) block, quadratus lumborum (QL) block, and caudal epidural block on perioperative analgesia in pediatric patients aged between 6 months and 14 years who underwent elective unilateral lower abdominal wall surgery.

Materials and methods

Ninety-four patients classified under the American Society of Anesthesiologists physical status classification system as ASA I or ASA II were randomly divided into 3 equal groups to perform TAP, QL or Caudal epidural block using 0.25% of bupivacaine solution (0.5 ml kg−1).

Results

Postoperative analgesic consumption was highest in the TAP block group (P < 0.05). In the QL block group, Pediatric Objective Pain Scale (POAS) scores were statistically significantly lower after 2 and 4 h (P < 0.05). The length of hospital stay was significantly longer in the caudal block group than the QL block group (P < 0.05).

Conclusion

We suggest that analgesia with ultrasound-guided QL block should be considered as an option for perioperative analgesia in pediatric patients undergoing lower abdominal surgery if the expertise and equipment are available.

Retrospective Analysis of Ultrasound-Guided Infraclavicular Block: Effect of Experience of Anesthesiologists on Volume of Local Anesthetic Administered

Performing a block under ultrasound guidance effectively requires skill; however, inexperienced anesthesiologists often use high-dose LA to ensure success. We aimed to share our experience with the ultrasound-guided infraclavicular brachial plexus block (USGICB) for upper extremity surgeries and to determine changes in failure rate and local anesthetic dose administered with gaining adequate experience. With approval from the local ethics committee, a retrospective review of records of 2953 patients who underwent USGICB between November 2011 and March 2015 was performed for evaluating the following data: age, sex, height, weight, operation type, American Society of Anesthesiologists physical status score, local anesthetic volume, complications, and success of USGICB. The patients were divided into 4 groups of 10 months each from November 2011 to March 2015: first 10-month period, 628 cases (group I); second 10-month period, 672 (group II); third 10-month period, 720 (group III); and the fourth 10-month period, 933 cases (group IV). Nine anesthesiologists with the same baseline experience in USG performed the blocks. During the initial period, when anesthesiologists had insufficient experience, local anesthetic (LA) dose, success rate, failed blocks, and complications were investigated. The LA volume administered in group I (33.7 ± 4.2 ml) was significantly higher than that in groups II, III, and IV (p < 0.05). Although a reduction in LA volume administered with increasing anesthesiologist experience was not statistically significant, a volume reduction of over 30 ml was observed in groups II, III, and IV compared with group I. Furthermore, in group I, failure rate (3.2%) was higher than that in groups II, III, and IV (p < 0.05). We concluded that sonographic guidance ensures a high success rate and that increased experience of anesthesiologists is associated with reduced complications and failure rate of blocks, in addition to prevention of LA overdose.

Emergency physician-performed ultrasound-guided nerve blocks in proximal femoral fractures provide safe and effective pain relief: a prospective observational study in The Netherlands

Background

The treatment of acute pain in the emergency department is not always optimal. Peripheral nerve blocks using “blind” or nerve stimulator techniques have substantial disadvantages. Ultrasound-guided regional anesthesia may provide quick, safe, and effective pain relief in patients with proximal femoral fractures with severe pain. However, no evidence exists on emergency physician-performed ultrasound-guided regional anesthesia in these patients in Dutch emergency departments. We hypothesized that emergency physicians can be effectively trained to safely perform and implement ultrasound-guided femoral nerve blocks, resulting in effective pain relief in patients with proximal femoral fractures.

Methods

In this prospective observational study, emergency physicians were trained by expert anesthesiologists to perform ultrasound-guided femoral nerve blocks during a single-day course. Femoral nerve blocks were performed on patients with proximal femoral fractures. A system of direct supervision by skilled anesthesiologists and residents was put in place.

Results

A total of 64 femoral nerve blocks were performed. After 30 min, blocks were effective in 69% of patients, and after 60 min, in 83.3%. The mean reduction in pain scores after 30 and 60 min was 3.84 and 4.77, respectively (both p <  0.001).

Patients reported a mean satisfaction of 8.42 (1 to 10 scale). No adverse events occurred.

Conclusions

Ultrasound-guided femoral nerve block is an effective, safe, and easy to learn (single-day course) procedure for emergency physicians to implement and perform in the emergency department. Patient satisfaction was high.

State of education regarding ultrasound-guided interventions during pain fellowships in Korea: a survey of recent fellows

Background

Recently, the use of ultrasound (US) techniques in regional anesthesia and pain medicine has increased significantly. However, the current extent of training in the use of US-guided pain management procedures in Korea remains unknown. The purpose of the present study was to assess the current state of US training provided during Korean Pain Society (KPS) pain fellowship programs through the comparative analysis between training hospitals.

Methods

We conducted an anonymous survey of 51 pain physicians who had completed KPS fellowships in 2017. Items pertained to current US practices and education, as well as the types of techniques and amount of experience with US-guided pain management procedures. Responses were compared based on the tier of the training hospital.

Results

Among the 51 respondents, 14 received training at first- and second-tier hospitals (Group A), while 37 received training at third-tier hospitals (Group B). The mean total duration of pain training during the 1-year fellowship was 7.4 months in Group A and 8.4 months in Group B. Our analysis revealed that 36% and 40% of respondents in Groups A and B received dedicated US training, respectively. Most respondents underwent US training in patient-care settings under the supervision of attending physicians. Cervical root, stellate ganglion, piriformis, and lumbar plexus blocks were more commonly performed by Group B than by Group A (P < 0.05).

Conclusions

Instruction regarding US-guided pain management interventions varied among fellowship training hospitals, highlighting the need for the development of educational standards that mandate a minimum number of US-guided nerve blocks or injections during fellowships in interventional pain management.

Randomized Comparison of Extrafascial Versus Subfascial Injection of Local Anesthetic During Ultrasound-Guided Supraclavicular Brachial Plexus Block

BACKGROUND AND OBJECTIVES

The optimal site for local anesthetic injection during an ultrasound-guided supraclavicular brachial plexus block (BPB) is not known. We tested the hypothesis that local anesthetic injected deep to the "brachial plexus sheath" during supraclavicular BPB would produce faster onset of surgical anesthesia than an injection superficial to the sheath.

METHODS

After research ethics approval and informed consent, 32 patients undergoing upper-extremity surgery under an ultrasound-guided supraclavicular BPB were randomly assigned to receive 25 mL of a 1:1 mixture of 2% lidocaine with 1:200,000 epinephrine and 0.5% bupivacaine, deep to (subfascial, Gp SF) or superficial to (extrafascial, Gp EF) the brachial plexus sheath. Sensory-motor blockade of the ipsilateral musculocutaneous, median, radial, and ulnar nerves and time to "readiness for surgery" (defined as a sensory and motor block scale of 1 in all the 4 nerves tested) were assessed by a blinded observer, using a 3-point qualitative scale (2 to 0), every 5 minutes for 40 minutes and at 2, 4, 6, 8, 10, 12, and 24 hours after surgery.

RESULTS

The time to "readiness for surgery" was significantly shorter (Gp SF: 7 ± 3 minutes vs Gp EF: 20 ± 10 minutes; P < 0.001), and the duration of postoperative analgesia was longer (Gp SF: 9.3 ± 1.4 hours vs Gp EF: 6.1 ± 1.4 hours; P < 0.001) in the subfascial group than in the extrafascial group. There were no complications directly related to the technique or the local anesthetic injection.

CONCLUSIONS

Injection of local anesthetic deep to the brachial plexus sheath at the supraclavicular fossa, under ultrasound-guidance, results in faster onset of surgical anesthesia and prolonged duration of postoperative analgesia than an injection superficial to the sheath.

Ultrasound-Guided Nerve Blocks in Emergency Medicine Practice

OBJECTIVES

The purpose of this study was to investigate the current practice of ultrasound (US)-guided regional anesthesia at academic emergency departments, including education, protocols, policies, and quality assessment.

METHODS

We conducted a cross-sectional study. A questionnaire on US-guided nerve blocks was electronically sent to all emergency US directors and emergency US fellowship directors.

RESULTS

A total of 121 of 171 academic institutions with an emergency medicine residency program participated in this study, representing a 71% response rate. Eighty-four percent (95% confidence interval [CI], 77%-91%) of programs perform US-guided nerve blocks at their institutions. The most common type of nerve block performed is a forearm nerve block (ulnar, median, or radial). The most common indication for US-guided nerve blocks is fracture pain management. Only 7% (95% CI, 2%-12%) of programs have a separate credentialing pathway for US-guided nerve blocks. Regarding quality assessment review of US-guided nerve blocks, none of the programs have a separate program in place. In 57% (95% CI, 48%-66%) of programs, it is a component of the emergency US quality assessment program. Eighty-four percent (95% CI, 77%-90%) of programs do not have specific agreements with other specialty services with regard to performing US-guided nerve blocks in the emergency department. The most common educational methods used to teach US-guided nerve blocks are didactic sessions, at 67% (95% CI, 59%-75%); online resources, at 54% (95% CI, 45%-63%); and supervised training with real patients, at 48% (95% CI, 39%-57%).

CONCLUSIONS

Ultrasound-guided nerve blocks are performed at most academic emergency departments. However, there is a substantial variation in the practices and policies within these institutions.

Efficacy of trans abdominis plane block for post cesarean delivery analgesia: A double-blind, randomized trial

Background:

The transverse abdominis plane (TAP) block, a regional block provides effective analgesia after lower abdominal surgeries if used as part of multimodal analgesia. In this prospective, randomized double-blind study, we determined the efficacy of TAP block in patients undergoing cesarean section.

Materials and Methods:

Totally, 62 parturients undergoing cesarean section were randomized in a double-blind manner to receive either bilateral TAP block at the end of surgery with 20 ml of 0.25% bupivacaine or no TAP block, in addition to standard analgesic comprising 75 mg diclofenac 8 hourly and intravenous patient-controlled analgesia (PCA) tramadol. Each patient was assessed at 0, 4, 8, 12, 24, 36, and 48 h after surgery by an independent observer for pain at rest and on movement using numeric rating scale of 0-10, time of 1^st demand for tramadol, total consumption of PCA tramadol, satisfaction with pain management and side effects. Results: Use of tramadol was reduced in patients given TAP block by 50% compared to patients given no block during 48 h after surgery (P < 0.001). Pain scores were lower both on rest and activity at each time point for 24 h in study group (P < 0.001), time of first analgesia was significantly longer, satisfaction was higher, and side effects were less in study group compared to control group.

Conclusion:

Transverse abdominis plane block was effective in providing analgesia with a substantial reduction in tramadol use during 48 h after cesarean section when used as adjunctive to standard analgesia.

Infraclavicular brachial plexus block for regional anaesthesia of the lower arm

BACKGROUND

Several approaches exist to produce local anaesthetic blockade of the brachial plexus. It is not clear which is the technique of choice for providing surgical anaesthesia of the lower arm, although infraclavicular blockade (ICB) has several purported advantages. We therefore performed a systematic review of ICB compared to the other brachial plexus blocks (BPBs). This review was originally published in 2010 and was updated in 2013.

OBJECTIVES

The objective of this review was to evaluate the efficacy and safety of infraclavicular block (ICB) compared to other approaches to the brachial plexus in providing regional anaesthesia for surgery on the lower arm.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2013, Issue 5); MEDLINE (1966 to June 2013) via OvidSP; and EMBASE (1980 to June 2013) via OvidSP. We also searched conference proceedings (from 2004 to 2012) and the www.clinicaltrials.gov trials registry. The searches for the original review were performed in September 2008.

SELECTION CRITERIA

We included any randomized controlled trials (RCTs) that compared ICB with other BPBs as the sole anaesthetic technique for surgery on the lower arm.

DATA COLLECTION AND ANALYSIS

The primary outcome was adequate surgical anaesthesia within 30 minutes of block completion. Secondary outcomes included sensory block of individual nerves, tourniquet pain, onset time of sensory blockade, block performance time, block-associated pain and complications related to the block.

MAIN RESULTS

In our original review we included 15 studies with 1020 participants and excluded two. In this updated review we included seven new studies and excluded six, bringing the total number of included studies to 22 and involving 1732 participants. The control group intervention was the axillary block in 14 studies, supraclavicular block in six studies, mid-humeral block in two studies, and parascalene block in one study. One study compared ICB to both axillary and supraclavicular blocks. Nine studies employed ultrasound-guided ICB. The risk of failed surgical anaesthesia 30 minutes after block completion was similar for ICB and all other BPBs (11.4% versus 12.9%, risk ratio (RR) 0.88, 95% CI 0.51 to 1.52, P = 0.64), but tourniquet pain was less likely with ICB (11.9% versus 18.0%; RR of experiencing tourniquet pain 0.66, 95% CI 0.47 to 0.92, P = 0.02). Subgroup analysis by method of nerve localization, and by control group intervention, did not show any statistically significant differences in the risk of failed surgical anaesthesia. However when compared to a single-injection axillary block, ICB was better at providing complete sensory block of the musculocutaneous nerve (RR for failure 0.46, 95% CI 0.27 to 0.60, P < 0.0001). ICB had a slightly longer sensory block onset time (mean difference (MD) 1.9 min, 95% CI 0.2 to 3.6, P = 0.03) but was faster to perform than multiple-injection axillary (MD -2.7 min, 95% CI -3.4 to -2.0, P < 0.00001) or mid-humeral (MD -4.8 min, 95% CI -6.0 to -3.6, P < 0.00001) blocks.

AUTHORS' CONCLUSIONS

ICB is as safe and effective as any other BPBs, regardless of whether ultrasound or neurostimulation guidance is used. The advantages of ICB include a lower likelihood of tourniquet pain during surgery, more reliable blockade of the musculocutaneous nerve when compared to a single-injection axillary block, and a significantly shorter block performance time compared to multi-injection axillary and mid-humeral blocks.

Near-infrared imaging in intravenous cannulation in children: a cluster randomized clinical trial

OBJECTIVE

Intravenous cannulation is a widespread medical procedure that can be difficult in children. Visualization of veins with near-infrared (NIR) light might support intravenous cannulation. Therefore, we investigated the effectiveness of an NIR vascular imaging system (VascuLuminator) in facilitating intravenous cannulation in children in the operating room.

METHODS

This was a pragmatic, cluster randomized clinical trial in all consecutive children (0-18 years) scheduled for elective surgery and in need of intravenous cannulation at a tertiary pediatric referral hospital. Daily operating rooms (770 patients) were randomized for allocation of the VascuLuminator or control group. The primary outcome was success at first attempt; the secondary outcome was time to successful cannulation.

RESULTS

Success at first attempt was 70% (171/246) with and 71% (175/245) without the use of the VascuLuminator (P = .69). Time to successful cannulation was 162 (± 14) seconds and 143 (± 15) seconds respectively (P = .26). In 83.3%, the vein of first choice was visible with the VascuLuminator.

CONCLUSIONS

Although it was possible to visualize veins with NIR in most patients, the VascuLuminator did not improve success rate or time to obtain intravenous cannulation. There are 3 possible explanations for this result: first, it could be that localization of the vein is not the main problem, and therefore visualization is not a solution; second, the type of system used in this study could be less than optimal; and, third, the choice of the patient population in this study could be inappropriate.

A method for ultrasonographic visualization and injection of the superior laryngeal nerve: volunteer study and cadaver simulation

Superior laryngeal nerve block is a valuable technique for provision of upper airway anesthesia. In bilateral scans of 20 volunteers, we developed a technique for ultrasonographic visualization of the superior laryngeal nerve and key anatomical structures using a hockey stick-shaped 8 to 15 MHz transducer (HST15 to 8/20 linear probe, Ultrasonix, Richmond, BC, Canada). Subsequently, we simulated superior laryngeal nerve scanning and injection in bilateral injections in 2 cadavers. Ultrasound-guided in-plane advancement of a needle toward the superior laryngeal nerve and injection of 1 mL of green dye was achieved in all 4 attempts and confirmed by a postprocedural dissection performed by an anatomist. We conclude that ultrasound-guided superior laryngeal nerve block in humans may be feasible.

Musculoskeletal sonopathology and ultrasound-guided regional anesthesia

The use of real-time ultrasound guidance has revolutionized the practice of regional anesthesia. Ultrasound is rapidly becoming the technique of choice for nerve blockade due to increased success rates, faster onset, and potentially improved safety. In the course of ultrasound-guided regional anesthesia, unexpected pathology may be encountered. Such anomalous or pathological findings may alter the choice of nerve block and occasionally affect surgical management. This case series presents a variety of musculoskeletal conditions that may be encountered during ultrasound-guided regional anesthesia practice.

Ultrasonographic applications after mass casualty incident caused by Wenchuan earthquake

BACKGROUND

Ultrasonography has been widely applied in clinical settings, and its role in the assessment of trauma has been approved. However, there are very few reports about its role in the management of mass casualties.

METHODS

In our hospital, we retrospectively analyzed the application, the methods, and the role of ultrasonography in rescuing the Wenchuan earthquake victims.

RESULTS

On a total of 3,307 wounded patients, 1,207 were examined by ultrasonography, and on a part of them, a follow-up was also performed. A total number of 1,386 ultrasound examinations were performed. Among them, 115 patients received ultrasound-guided interventional diagnosis and treatments. Ultrasound screening detected 23 cases of hemoperitoneum, 45 cases of pleural effusion (blood), 1 case of traumatic intimal tear of femoral artery, 3 cases of deep veins phlebothrombosis of lower limbs, 12 cases of deep-part hematoma of soft tissues. In five cases of negative results by ultrasonography, visceral injury was confirmed later by surgery or computed tomography or contrast-enhanced ultrasonography. All the ultrasound-guided interventional treatments were performed successfully, without any serious complication. The detection rate of trauma-related diseases was 6.96% (84 of 1,207) without false positive; however, the false negative rate was 5.6% (5 of 89). The bedside ultrasound became the preferred examination for the majority of injuries in middle and later stage after earthquake (72 hours to 6 weeks), accounting for 73.9% (458 of 620) of examinations. Ultrasonography-based FAST method was the primary examination tool of trauma in the early stage after earthquake.

CONCLUSION

In our hospital, ultrasonography was widely used in the triage of earthquake victims, bedside examination of severe cases, and interventional treatments. The advantages of ultrasonography such as convenience, noninvasiveness, high accuracy, and repeatability have been sufficiently demonstrated in this mass casualty, where ultrasonography played a great role in the rescue of victims of Wenchuan earthquake.

Infraclavicular brachial plexus block for regional anaesthesia of the lower arm

BACKGROUND

Several approaches exist to produce local anaesthetic blockade of the brachial plexus. It is not clear which is the technique of choice for providing surgical anaesthesia of the lower arm although infraclavicular blockade (ICB) has several purported advantages. We therefore performed a systematic review of ICB compared to the other brachial plexus blocks (BPBs).

OBJECTIVES

To evaluate the efficacy and safety of ICB compared to other BPBs in providing regional anaesthesia of the lower arm.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2008, Issue 3), MEDLINE (1950 to September 22nd 2008) and EMBASE (1980 to September 22nd 2008). We also searched conference proceedings (from 2004 to 2008) and the www.clinicaltrials.gov registry. No language restriction was applied.

SELECTION CRITERIA

We included any randomized controlled trials that compared ICB with other BPBs as the sole anaesthetic techniques for surgery on the lower arm.

DATA COLLECTION AND ANALYSIS

The primary outcome was adequate surgical anaesthesia within 30 minutes of block completion. Secondary outcomes included sensory block of individual nerves, tourniquet pain, onset time of sensory blockade, block performance time, block-associated pain and complications related to the block.

MAIN RESULTS

We identified 15 studies with 1020 participants, of whom 510 received ICB and 510 received other BPBs. The control group intervention was the axillary block in 10 studies, mid-humeral block in two studies, supraclavicular block in two studies and parascalene block in one study. Three studies employed ultrasound-guided ICB. The risk of failed surgical anaesthesia and of complications were low and similar for ICB and all other BPBs. Tourniquet pain was less likely with ICB (risk ratio (RR) 0.47, 95% CI 0.24 to 0.92, P = 0.03). When compared to a single-injection axillary block, ICB was better at providing complete sensory block of the musculocutaneous nerve (RR for failure 0.46, 95% CI 0.27 to 0.60, P < 0.0001) and the axillary nerve (RR of failure 0.37, 95% CI 0.24 to 0.58, P < 0.0001). ICB was faster to perform than multiple-injection axillary (mean difference (MD) -2.7 min, 95% CI -4.2 to -1.1, P = 0.0006) or midhumeral blocks (MD -4.8 min, 95% CI -6.0 to -3.6, P < 0.00001) but this was offset by a longer sensory block onset time (MD 3.9 min, 95% CI 3.2 to 4.5, P < 0.00001).

AUTHORS' CONCLUSIONS

ICB is a safe and simple technique for providing surgical anaesthesia of the lower arm, with an efficacy comparable to other BPBs. The advantages of ICB include a lower likelihood of tourniquet pain during surgery, and more reliable blockade of the musculocutaneous and axillary nerves when compared to a single-injection axillary block.

New anticoagulants and regional anesthesia

PURPOSE OF REVIEW

The use of pharmacological thromboprophylaxis in the perioperative period may conflict with regional anesthetic techniques in which maintaining hemostatic integrity is essential. Recently, new anticoagulants have been developed with more efficacy and a better safety profile. This article reviews the basis for the actual recommendations and the current status and management of these new drugs.

RECENT FINDINGS

Recent studies have outlined that the risk of epidural hematoma after neuraxial anesthesia may be higher than estimated. Therefore, it is imperative to follow the published recommendations. The use of new anticoagulant drugs may take into account the pharmacological profile of each one to safely perform regional anesthesia, mainly the time to reach peak plasma level and half-life.

SUMMARY

When new anticoagulant drugs are used for thromboprophylaxis in orthopedic surgery, the performance of neuraxial anesthetic techniques should be based on their pharmacology. If a peripheral blockade is chosen, these recommendations should be followed when a block is performed in a noncompressible area.

Ultrasound-guided nerve blocks: efficacy and safety

The introduction of affordable, portable and high-resolution ultrasound machines has rejuvenated interest in regional anaesthesia. The inherent benefits of direct visualisation of nerves and surrounding anatomy, continual observation of the needle tip and spread of local anaesthetic make ultrasound-guided regional anaesthesia highly appealing. However, in the cost-conscious health-care setting and to convince sceptics, there also needs to be evidence of increased benefits and reduced complications. Ultrasound is a rapidly developing area of technology and some of the newer modalities are discussed. This article focusses on the recent growing evidence to support the benefits of its use in nerve and plexus blocks. Common complications of nerve blocks can be avoided with ultrasound but have still been reported. Anatomical variants have been demonstrated by ultrasound and it has proved to be useful in performing regional anaesthesia in difficult situations or where peripheral nerve stimulation is unsuccessful or inappropriate.

The use of ultrasound to facilitate spinal anesthesia in a patient with previous lumbar laminectomy and fusion: a case report

We describe a case of ultrasound (US)-facilitated spinal anesthesia in a patient with a prior lumbar laminectomy and spinal fusion who presented for total knee arthroplasty. Traditional, landmark-guided spinal anesthesia had previously failed. Although pre-procedural US identified a soft-tissue window at L3/4, a 25G pencilpoint needle encountered resistance. Reassured from US imaging that this was not bone, we used a 22G cutting tip needle successfully. We believe spinal anesthesia would not have been possible in this patient without US, adding to the evidence that US-facilitated neuraxial anesthesia is useful, particularly in technically difficult, if not 'impossible,' cases.