Ultrasound guidance improves success rate of axillary brachial plexus block

The ED95 of lidocaine and prilocaine for ultrasound-guided brachial plexus blocks for surgical anaesthesia: a randomised controlled clinical trial

Background

Our trial addresses the gaps in the current literature by directly estimating the ED95 of short-acting local anaesthetics for ultrasound-guided axillary and supraclavicular brachial plexus blocks for surgical anaesthesia.

Methods

Four double-blind prospective studies were organized in two separate arms. Patients were randomised between studies A (lidocaine 1% with adrenaline) and B (lidocaine 2% with adrenaline) for axillary blocks and between studies C (prilocaine 1%) and D (lidocaine 1% with adrenaline) for supraclavicular blocks. All statistical modelling and analysis were performed using the modified continual reassessment method. The primary endpoint of the studies was the loss of cold and pin-prick sensations in the sensory distributions of the median, musculocutaneous, radial, and ulnar nerves.

Results

For axillary blocks, the estimated ED95 of lidocaine 1% with adrenaline was 40 ml (95% credibility interval: 89.5-99.2%), and lidocaine 2% with adrenaline was 15 ml (95% credibility interval: 87.4-97.5%) (studies A and B: 41 and 40 patients, respectively). The ED95 could not be determined for supraclavicular blocks as it fell outside the dose range considered in the studies (studies C and D: 31 and 42 patients, respectively).

Conclusions

We achieved a 95% success rate for axillary blocks using lidocaine (1% and 2%) with adrenaline within our dosing limits. For supraclavicular blocks, >40 ml of prilocaine 1% or lidocaine 1% with adrenaline may be required to consistently achieve a 95% success rate. Our studies highlight the continual reassessment method as a credible methodology for dose-finding studies in regional anaesthesia.

Clinical trial registration

EudraCT ref: 2010-018466-22.

Enhancing Safety in Regional Anesthesia: Guidelines from the Italian Society of Anesthesia, Analgesia, Resuscitation and Intensive Care (SIAARTI)

BACKGROUND

Regional anesthesia techniques have become integral to modern perioperative care, offering enhanced pain management and recovery outcomes. However, their application in patients with specific conditions, such as anticoagulation therapy or preexisting comorbidities, raises concerns regarding safety and efficacy. Current guidelines addressing these issues are fragmented, necessitating comprehensive, evidence-based recommendations.

METHODS

A multidisciplinary panel of experts in anesthesiology and pain management was convened under the auspices of the Italian Society of Anesthesia, Analgesia, Resuscitation, and Intensive Care (SIAARTI). The guidelines presented herein were developed according to the GRADE system (Grading of Recommendations of Assessment Development and Evaluations), in compliance with the methodological manual for the production of clinical practice guidelines published by the National Center for Clinical Excellence, Quality, and Safety of Care, Italian National Institute of Health.

RESULTS

The guidelines encompass recommendations on neuraxial blocks in anticoagulated patients, the dual guidance use in peripheral nerve blocks, the role of sterile field preparation, and post-procedural monitoring. Evidence from meta-analyses and large-scale observational studies supported most recommendations, though limitations in study heterogeneity were noted.

CONCLUSIONS

These guidelines provide a structured framework for clinicians to enhance patient safety and procedural efficacy in regional anesthesia. Further research is encouraged to address identified gaps, particularly regarding specific patient subgroups and novel regional anesthesia techniques.

Local Anaesthesia of the Bovine Tarsus: A Cadaver Study Comparing Anatomical Landmark-Based and Ultrasound-Guided Nerve Blocks

Surgical procedures involving the tarsal joint are common in cattle. Indications for tarsal surgery include joint lavage, arthrotomy, the treatment of injuries, and hygromas. The goal of the present study was to lay the foundation for a reliable method of nerve block desensitisation of the bovine tarsus. Two nerve block techniques were simulated in an anatomical cadaver study on six bovine pelvic limbs for each technique. In the first technique, injection sites were based on palpation of anatomical structures, and in the second technique, ultrasound guidance was used to localise the nerves. After injection of dye (methylene blue) solution using anatomical landmark-based or ultrasound guidance methods, the 12 cadaver limbs were dissected, and the effectiveness of sham anaesthesia was determined based on the proximity of the dye solution to the nerve and the length of its distribution along the nerve. The ultrasound-guided local anaesthesia required significantly more time to perform compared with nerve blocks based on anatomical landmarks. However, the dye reached the target area in 25 of 30 application sites using ultrasound-guided local anaesthesia compared with 13 of 30 sites using the anatomical landmark-based technique. Ultrasonographic guidance led to fewer inadvertent intravascular and intramuscular injections. In conclusion, the ultrasound-guided local anaesthesia is a promising alternative to general anaesthesia, epidural, and intravenous regional anaesthesia for surgical procedures of the bovine tarsal joint and eliminates the disadvantages of other anaesthetic techniques, like general anaesthesia and intravenous regional anaesthesia. The practicability and utility of this technique still require validation in vivo.

Postoperative pain control for shoulder arthroplasty

Since its inception in 1893, shoulder arthroplasty has become an increasingly common surgical procedure. Between 1998 and 2008, shoulder arthroplasty procedures increased by nearly 28,000 cases per year in the United States alone and is the fastest growing joint replacement surgery among all joint. Despite its advantages, shoulder arthroplasty is often accompanied by significant postoperative pain. Pain control continues to be a major concern in patient management, as it impacts operative costs, postoperative mobility, length of hospital stay, patient satisfaction, and overall surgical outcomes. This review aims to provide an overview of drugs such as opioids and regional anesthetics, as well as methods such as local wound infiltration, nerve block, brachial plexus infiltration, cryotherapy and multimodal approaches employed in postoperative shoulder arthroplasty pain control.

Upper Extremity Blocks for Hand Surgeons: A Literature Review of Regional Anaesthesia Techniques, Efficacy, and Safety

Introduction: Regional anaesthesia (RA) techniques have increased in popularity due to evidence of reductions in acute pain, chronic pain, postoperative nausea and vomiting (PONV), and pulmonary complications. While upper extremity blocks (UEBs) have been the subject of several comprehensive reviews, no review to date has synthesised the information on their use in hand surgery. Methods: A search of PUBMED and Cochrane databases was performed to identify the evidence associated with upper extremity blocks. The results of this search and extant literature on UEBs were examined and the relevant information extracted. Results: Supraclavicular block is associated with transient complications such as Horner's syndrome and phrenic nerve palsy, affecting up to 54% and 50% of patients, respectively. The incidence of pneumothorax in supraclavicular blocks is up to 4%. Infraclavicular, interscalene and axillary blocks have a lower rate of all complications, however, each may require a supplementary block at a different anatomical site as each spares significant regions of the upper extremity. Epinephrine in concentrations of 1:100,000-200,000 is safe for use in digital blocks with no association digital gangrene. Current evidence suggests digital blocks are safe and efficacious when appropriately performed. Conclusion: UEBs are safe and may be administered by an anaesthesia provider or an appropriately trained surgeon. The choice of block is contingent on the anatomical location of the surgical procedure, procedure duration, patient preference, patient co-morbidieis, and the surgeon's experience. Most upper extremity surgeries can be performed using RA. Current evidence illustrates outcome benefits for patients, surgeons, and healthcare institutions utilising RA.

Effectiveness of Regional Nerve Blocks Versus Local Anesthetic Infiltration for Elective Hand and Wrist Surgery

BACKGROUND

Pain relief by different methods in elective hand and wrist surgery is pivotal for patients undergoing elective wrist and hand surgery.

AIM

To evaluate the effectiveness and duration of peripheral nerve block versus local surgical site anesthetic infiltration among patients undergoing elective wrist and hand surgery.

SUBJECTS AND METHODS

This study was carried out in the Orthopaedic Department of Duhok Emergency Teaching Hospital, Duhok, Kurdistan region, Iraq. All patients who attended the Orthopaedic Department (total number=496) for elective hand and wrist surgery between November 2021 and November 2022 were included in the study, but only 300 patients completed the study protocol after the exclusion of 196 patients. Three methods of nerve block were used for postoperative pain relief. The degree and duration of pain relief were assessed.

RESULTS

Patients who underwent ultrasound-guided nerve block had more duration of pain relief when compared to those patients who underwent local surgical site anesthetic infiltration and anatomical landmark nerve block (p<0.01), while patients who underwent local surgical site anesthetic infiltration had better pain relief when compared to those patients who underwent ultrasound-guided nerve block and anatomical landmark nerve block (p<0.01 for the group experiencing mild pain and p=0.12 for the group experiencing moderate pain and p<0.01 for the group experiencing severe pain).

CONCLUSION

Ultrasound-guided nerve block is better for a longer duration of pain relief postoperatively than local surgical site anesthetic infiltration, while local surgical site anesthetic infiltration more effectively controls the severity of pain following elective hand and wrist surgery.

Effect of Neurostimulator Usage on Block Success in Costoclavicular Block: A Randomized Controlled Trial

BACKGROUND

The need of a neurostimulator for a successful nerve block was questioned in different block types after ultrasound had become standard.

AIM

To determine the effect of neurostimulator use on block success in the costoclavicular block (CCB).

METHODS

Sixty patients undergoing upper limb surgery were enrolled in the study. Patients using ultrasound and injection pressure manometer were divided as Group USP, and those using ultrasound, injection pressure manometer, and neurostimulator were divided as Group USPN. After block was applied, sensory and motor block levels were measured on a numeric scale. The block was considered successful when the desired score was reached or general anesthesia was not required intraoperatively. The number of successful and unsuccessful blocks for each group was summed up. The successful block rate was compared as the primary objective. Block application time, time to readiness for surgery, the number of needle passes, diaphragm paralysis rate, and complication rate were compared as secondary goals.

RESULTS

Block success rate was 90% (27/30) in Group USP and 96.7% (29/30) in Group USPN. There was no statistical difference in terms of block success rate. Block application time was significantly shorter in Group USP (207.2 ± 32.7 s) when compared to Group USPN (280.9 ± 70.1 s). Other secondary outcomes were similar.

CONCLUSION

Neurostimulator use did not affect block success in the CCB. Neurostimulator utilization prolonged block application time explicitly and did not change the complication rate. Ultrasound and injection pressure manometer are sufficient for a safe and successful CCB.

Neurological injury following peripheral nerve blocks: a narrative review of estimates of risks and the influence of ultrasound guidance

BACKGROUND

Peripheral nerve injury or post-block neurological dysfunction (PBND) are uncommon but a recognized complications of peripheral nerve blocks (PNB). A broad range of its incidence is noted in the literature and hence a critical appraisal of its occurrence is needed.

OBJECTIVE

In this review, we wanted to know the pooled estimates of PBND and further, determine its pooled estimates following various PNB over time. Additionally, we also sought to estimate the incidence of PBND with or without US guidance.

EVIDENCE REVIEW

A literature search was conducted in six databases. For the purposes of the review, we defined PBND as any new-onset sensorimotor disturbances in the distribution of the performed PNB either attributable to the PNB (when reported) or reported in the context of the PNB (when association with a PNB was not mentioned). Both prospective and retrospective studies which provided incidence of PBND at timepoints of interest (>48 hours to <2 weeks; >2 weeks to 6 weeks, 7 weeks to 5 months, 6 months to 1 year and >1 year durations) were included for review. Incidence data were used to provide pooled estimates (with 95% CI) of PBND at these time periods. Similar estimates were obtained to know the incidence of PBND with or without the use of US guidance. Additionally, PBND associated with individual PNB were obtained in a similar fashion with upper and lower limb PNB classified based on the anatomical location of needle insertion.

FINDINGS

The overall incidence of PBND decreased with time, with the incidence being approximately 1% at <2 weeks' time (Incidence per thousand (95% CI)= 9 (8; to 11)) to approximately 3/10 000 at 1 year (Incidence per thousand (95% CI)= 0. 3 (0.1; to 0.5)). Incidence of PBND differed for individual PNB with the highest incidence noted for interscalene block.

CONCLUSIONS

Our review adds information to existing literature that the neurological complications are rarer but seem to display a higher incidence for some blocks more than others. Use of US guidance may be associated with a lower incidence of PBND especially in those PNBs reporting a higher pooled estimates. Future studies need to standardize the reporting of PBND at various timepoints and its association to PNB.

Guidance for clinical practice using emergency and point-of-care ultrasonography

Owing to the miniaturization of diagnostic ultrasound scanners and their spread of their bedside use, ultrasonography has been actively utilized in emergency situations. Ultrasonography performed by medical personnel with focused approaches at the bedside for clinical decision-making and improving the quality of invasive procedures is now called point-of-care ultrasonography (POCUS). The concept of POCUS has spread worldwide; however, in Japan, formal clinical guidance concerning POCUS is lacking, except for the application of focused assessment with sonography for trauma (FAST) and ultrasound-guided central venous cannulation. The Committee for the Promotion of POCUS in the Japanese Association for Acute Medicine (JAAM) has often discussed improving the quality of acute care using POCUS, and the "Clinical Guidance for Emergency and Point-of-Care Ultrasonography" was finally established with the endorsement of JAAM. The background, targets for acute care physicians, rationale based on published articles, and integrated application were mentioned in this guidance. The core points include the fundamental principles of ultrasound, airway, chest, cardiac, abdominal, and deep venous ultrasound, ultrasound-guided procedures, and the usage of ultrasound based on symptoms. Additional points, which are currently being considered as potential core points in the future, have also been widely mentioned. This guidance describes the overview and future direction of ultrasonography for acute care physicians and can be utilized for emergency ultrasound education. We hope this guidance will contribute to the effective use of ultrasonography in acute care settings in Japan.

Ultrasound-Guided Block of the Sciatic and the Femoral Nerves in Rabbits-A Descriptive Anatomical Study

The rabbit is a popular animal model for human biomechanical research involving surgery on the hind limb. Mortality is higher in rabbits when undergoing general anesthesia compared to dogs and cats. Moreover, due to their nature as prey animals, rabbits have a tendency to hide signs of pain, making it challenging to detect discomfort at an early stage. Incorporating regional anesthesia into an anesthetic protocol can greatly reduce the requirements for systemic anesthetic and analgesic drugs, thereby minimizing associated side effects. In other species, a block of the sciatic (ScN) and the femoral nerves (FN) is usually applied in patients undergoing hind limb surgery. In phase 1 of this study, the ScN and the FN have been localized and an appropriate approach has been evaluated under sonographic guidance. In phase 2, a mixture of new methylene blue and lidocaine have been administered to the ScN and the FN in 10 cadavers (20 hind limbs). Staining of the nerves was evaluated by dissection. Ultrasonographically, the ScN appeared as a binocular structure surrounded by a hyperechoic rim. The FN appeared as a hypoechoic structure in the dorsal part of the iliopsoas muscle (IPM), becoming hyperechoic/honey-comb-like in the ventral part. Both nerves could be successfully stained in all animals over a median length of 2.3 cm which was considered effective. This technique allows feasible and accurate access to block the ScN and the FN and may lead to successful analgesia in rabbits undergoing hind limb surgery.

Investigating 3D-printed disk compressing against skin for pain relief in intradermal infiltration anesthesia: a randomized controlled trial

BACKGROUND

Pain intensity may be varied during the needle advancing through different skin layers, injection into the intradermal layer may exclude mixed pain from deeper planes. This study aimed to investigate whether compressing a three-dimensional (3D)-printed disk against the skin may relieve pain associated with intradermal injection of local anesthetic which mimics the skin test procedure.

METHODS

After institutional review board approval, 3D-printed disks with projections were designed for this study. Enrolled patients were randomized to receive either a disk compressing against the axillary skin during the intradermal injection of local anesthesia (compressing disk group) or an intradermal injection of local anesthesia without any compression (no compressing disk group). The primary outcomes were pain intensity (100-mm visual analog scale) and satisfaction (5-point Likert scale) as assessed by patients.

RESULTS

Ninety patients with American Society of Anesthesiologists I-II physical status receiving intradermal local anesthesia prior to an ultrasound-guided axillary approach were included. Eighty-seven patients completed the study, with 44 and 43 patients in disk and no disk groups, respectively. Pain scores were significantly different (P < 0.001) in compressing disk (median, 10; IQR, 5-20) and no compressing disk (median, 30; IQR, 20-40) groups. The median satisfaction score was 5 in both groups. No complications occurred during follow-up.

CONCLUSION

Compressing a 3D-printed disk against the skin may reduce intradermal needle pain and offers an effective alternative for nerve block induction.

Rectus sheath block versus local anesthetic infiltration in pediatric laparoscopic inguinal hernia repair: a randomized controlled trial

BACKGROUND

Rectus sheath block (RSB) and local anesthetic infiltration (LAI) are used for postoperative analgesia in pediatric laparoscopic inguinal hernia repair. However, whether the analgesic effect of RSB is superior to LAI remains unclear. The authors hypothesized that RSB would reduce opioid consumption in patients.

METHODS

Patients aged 3-14 years scheduled for laparoscopic inguinal hernia repair were randomly allocated to the RSB, local anesthetic infiltration high concentration (LAIHC), local anesthetic infiltration low concentration (LAILC), or control groups. Preoperatively, they received 0.4 ml/kg of 0.25% ropivacaine (RSB), 0.4 ml/kg of 0.25% ropivacaine (LAILC), or 0.2 ml/kg of 0.5% ropivacaine(LAIHC), and 0.2 ml/kg of normal saline (control). The primary outcome was equivalent morphine consumption.

RESULTS

The authors analyzed 136 patients (RSB, 33; LAIHC, 34; LAILC, 35; control, 34). Intraoperative morphine equivalent consumption was lower in the RSB group [0.115 (0.107-0.123)] than in the LAIHC [0.144 (0.137-0.151)], LAILC [0.141 (0.134-0.149)], and control [0.160 (0.151-0.170)] groups ( P <0.001). In the post-anesthesia care unit, morphine equivalent consumption differed between the RSB [0.018 (0.010-0.027)], LAIHC [0.038 (0.028-0.049)], LAILC [0.056 (0.044-0.067)], and control [0.074 (0.063-0.084)] groups ( P <0.001). The rescue morphine equivalent consumption did not differ significantly between the RSB [0.015 (0.007-0.023)] and LAIHC [0.019 (0.010-0.029)] groups, which were lower than that in the control group [0.037 (0.029-0.045)] ( P =0.001).

CONCLUSIONS

RSB can provide effective analgesia for pediatric laparoscopic inguinal hernia repair, with better effectiveness than that of LAI at the same dose.

Comparison of Ultrasound-Guided Superior Laryngeal Nerve Block with the Traditional Method for Direct Laryngoscopic Biopsy of Supraglottic Masses: A Clinical Trial

Background

A bilateral superior laryngeal nerve block (SLNB) can provide complete anesthesia for laryngeal sampling and by providing this block we can manage the biopsy of supraglottic masses without the complications of general anesthesia.

Objectives

This study aimed to compare 2 superior laryngeal nerve block (SLNB) methods using ultrasound and the traditional method for direct laryngoscopic surgery for the biopsy of supraglottic masses.

Methods

In this single-blind clinical trial, 50 patients undergoing supraglottic laryngeal mass biopsy under direct laryngoscopy were divided into 2 groups. The first group was anatomical landmark bilateral SLNB (C group), and the second group was sono-guided bilateral SLNB (U group). Hemodynamic changes, pain, oxygen desaturation, surgeon satisfaction, and the complication obtained and noted.

Results

There was no significant difference in the success rate of the procedure (P = 0.99), as well as the surgeon's satisfaction with the procedure (P = 0.337). Mean arterial pressure (MAP), oxygen saturation, and their changes in the studied groups were compared before the block, after the block, after the biopsy, and in the recovery room, showing no significant difference between the 2 groups (P > 0.05). Only the heart rate (HR) after the biopsy and in the recovery room showed significant differences between the 2 groups (P < 0.05). There was no significant difference between the 2 groups in the level of patient and surgeon satisfaction and pain during and after the procedure (P > 0.005).

Conclusions

SLNB for direct laryngoscopic surgery for biopsy of supraglottic masses using ultrasound was not significantly superior to the traditional method, and there was no significant difference between the 2 methods in terms of procedure success, surgeon's satisfaction, and patients' pain.

Comparison of the effectiveness of ultrasound-guided and ultrasound-guided subgluteal nerve blocks with peripheral nerve electrical stimulation: A randomized controlled feasibility trial

AIM: The efficacy of sciatic nerve blockade with subchondral access under ultrasound guidance (USG) versus ultrasound guidance in combination with EPN (USEPN) is unknown. Data on studies of these techniques for blockade of other peripheral nerves are inconsistent. This study evaluated the feasibility of a randomized trial to compare the efficacy of sciatic nerve blockade with USG-guided sciatic access with the current practice of USEPN. MATERIALS AND METHODS: Forty patients were randomized into two groups in which USG or USEPN guidance was used to perform sciatic nerve blockade with sciatic access. The primary endpoint was the quality of the sensory block. The secondary endpoint was the quality of the motor block. RESULTS: Two groups of 20 patients each were analyzed. All patients developed successful motor and sensory blocks of the sciatic nerve when using USG and USEPN. All cases were followed. Three patients were excluded before randomization because of the unsatisfactory ultrasound imaging of the sciatic nerve. CONCLUSION: The results show that a prospective study of alternative techniques of sciatic nerve block by subchondral access is possible. In our pilot study, sciatic nerve block performed under USG guidance without EPN was effective in all cases.

Peripheral Nerve Injury After Upper-Extremity Surgery Performed Under Regional Anesthesia: A Systematic Review

Purpose

Peripheral nerve injury (PNI) is a known adverse event following upper-limb surgery performed under brachial plexus regional anesthesia (RA). When PNI is noted after surgery, patients and providers often have questions about which factors might have contributed to this complication. This systematic review evaluates the literature on hand and shoulder surgeries performed under ultrasound-guided, plexus RA to identify factors potentially associated with PNI, including the surgery location and block type. We hypothesized that shoulder surgery might be associated with an increased risk of PNI compared to hand surgery.

Methods

A systematic review of the relevant literature was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Only prospective studies on the use of ultrasound-guided, preoperative, brachial plexus RA for hand or shoulder surgery on adult patients were included. Study groups were categorized according to surgery location and block type and compared across a number of factors via univariate and multivariate analyses.

Results

A total of 3,037 abstracts were screened; 192 full-text articles were independently reviewed by 2 of the authors; and 53 studies were included in the systematic review analysis. Following hand surgery, PNI was reported at an average rate of 1.35% ± 3.21% across 836 subjects in 40 study groups; after shoulder surgery, the average rate was 0.50% ± 1.57% across 3,383 subjects in 15 study groups. There was no statistically significant correlation between the incidence of PNI and surgery location (P =.70) or any of the most common approaches for brachial plexus anesthesia in the multivariate analysis.

Conclusions

This systematic review of over 50 articles on upper-limb surgery performed under RA shows no association between the incidence of PNI and the location of surgery or type of brachial plexus block.

Type of study/level of evidence

Diagnostic II.

Perineural Administration of Dexmedetomidine in Axillary Brachial Plexus Block Provides Safe and Comfortable Sedation: A Randomized Clinical Trial

Dexmedetomidine prolongs the duration of regional block while its systemic sedative effect when administered perineurally is unknown. We aimed to evaluate the systemic sedative effect of perineural dexmedetomidine in patients after axillary brachial plexus block (ABPB). This single-blinded prospective randomized control trial included 80 patients undergoing wrist surgery receiving ABPB. Patients were randomized into two groups – Control group (CG, N = 40) and dexmedetomidine group (DG, N = 40). Both groups received ABPB with 20 ml of 0.5% Bupivacaine and 10 ml of 2% Lidocaine. Additionally, patients in DG received 100 mcg of dexmedetomidine perineurally. Depth of sedation was evaluated using Narcontrend Index (NI) and Ramsay Sedation Scale (RSS) immediately after ABPB and in several time points up to 120 min. Duration of block as well as patient satisfaction with sedation was evaluated using a postoperative survey. Our results showed that NI and RSS statistically differed between groups, presenting a deeper level of sedation during the first 90 min in DG compared to controls, P < 0.001. In the first 10 to 60 min after ABPB the median RSS was 4 (IQR within median) and median NI was 60 (IQR 44–80) in DG group, in contrast to CG patients where median RSS was 2 (IQR within median) and median NI was 97 (IQR 96–98) throughout surgery. The level of sedation became equal in both groups 90 and 120 min after ABPB when the median NI value was 98 (97–99) in DG and 97.5 (97–98) in CG, P = 0.276, and the median RSS was 2 (IQR within median) in both groups, P = 0.128. No significant intergroup differences in hemodynamic or respiratory parameters were found. Patients in DG expressed satisfaction with sedation and 86.5% noted that the sensation was similar to ordinary sleep. In DG mean duration of motor block was 13.5 ± 2.1 h and sensory block was 12.7 ± 2.8 h which was significantly longer compared to CG 6.3 ± 1.5 h, P < 0.001 and 6.4 ± 1.8 h, P < 0.001. We found that beside prolongation of analgesia, perineural administration of dexmedetomidine might provide rather safe and comfortable sedation with no significant effect on hemodynamic or respiratory stability and yields a high level of patient satisfaction.

What Is the Minimum Effective Volume of Local Anaesthetic Applied in Brachial Plexus Blockage With an Axillary Approach Under Ultrasonography Guidance?

Peripheral nerve blocks with the use of ultrasonography (USG) allow visualisation of both the structures and nerves and make the block administrations safe, quick, and comfortable. However, few publications concerning the minimum local anesthetic (LA) volume are capable of providing blocks. This study aimed to find the minimum effective LA volume in brachial plexus blockage administrations with an axillary approach accompanied by ultrasonography in hand, elbow, and forehand operations. Materials and Method The study included a total of 55 patients (classified as American Society of Anesthesiologists (ASA) I-II) who underwent hand surgery by administering USG-guided axillary brachial plexus blockage. The ulnar, median, and radial nerves were located, and the minimum effective LA volume was investigated starting with a total of 21 ml of bupivacaine 0.5%. After accomplishing the blockage, the volume was decreased by 0.5 ml for each nerve. Block administration time, block onset times, anesthesia times, and time to first analgesic requirement were recorded. Results The minimum effective LA volume for each nerve was 2.5 ml for a total of 7.5 ml. In comparing block administration times, there were no differences between high or low volume groups. It was found that sensory block onset time was 17 minutes for 7.5 ml and 11 minutes for 21 ml; sensory block regression time was six hours for 7.5 ml and 10.4 hours for 21 ml, respectively. This regression was statistically significant. The first analgesic requirement was 5.8 - 16.6 hours, respectively, for each group. Conclusion In the administration of an USG-guided axillary block, sufficient anesthesia can be achieved by administering 2.5 ml of bupivacaine 0.5% for each nerve. However, it might be kept in mind that motor and sensory block onset time will be extended and regression time and time to the first analgesic requirement will be shorter with this volume. In addition, more advanced studies must be done for the determination of the optimum volume which can be used.

Minimum effective volume of 0.2% ropivacaine for ultrasound-guided axillary brachial plexus block in preschool-age children

Ultrasound-guided axillary brachial plexus block is increasingly used in preschool-age patients. However, the minimum effective volume of local anaesthetics has not been determined. With ethical committee approval and written informed consent from the guardians of all paediatric patients, we studied 27 consecutive patients aged 3 to 6 years who were scheduled for hand surgery. After general anaesthesia, eligible patients received a set volume of ultrasound-guided axillary brachial plexus block. We determined the volume of 0.2% ropivacaine for consecutive patients from the preceding patient's outcome. The initial volume was 0.4 ml/kg. The testing interval was set at 0.05 ml/kg, and the lowest volume was 0.1 ml/kg. The following conditions were defined as a successful block: no heart rate changes, body movement, or ventilatory disorders during the operation; no use of fentanyl in the PACU; and a postoperative sensory block score < 3. The sequences of positive and negative blocks in consecutive patients were recorded. Using probit regression analysis, the 50% effective volume was 0.185 ml/kg (95% CI 0.123-0.234), and the 95% effective volume was 0.280 ml/kg (95% CI 0.232-0.593). EV50 and EV95 values of 0.2% ropivacaine for ultrasound-guided axillary brachial plexus block were 0.185 ml/kg and 0.280 ml/kg, respectively.

Proximal Perineural Femoral Nerve Injection in Pigs Using an Ultrasound-Guided Lateral Subiliac Approach-A Cadaveric Study

Simple Summary

Desensitizing the femoral nerve improves pain control in several species undergoing pelvic limb surgeries. Despite possible advantages, this method has not yet been described in pigs, although they make an accepted surgical animal model. We developed an approach for femoral nerve blockade using ultrasound guidance in pigs which could be useful for pain control in pigs undergoing pelvic limb surgery.

Abstract

Desensitizing the femoral nerve (FN) improves pain control in several species undergoing pelvic limb surgeries. Despite its advantages, this method has not yet been described in pigs, although they make an accepted surgical animal model. Based on anatomical dissections, first performed in two pig cadavers, an ultrasound-guided access for localization and perineural infiltration of the FN trunk at the iliopsoas compartment level was specified. The FN was found running between the psoas major and medial portion of iliac muscle. Ultrasonographically, the FN appeared as a hypoechogenic round–oval structure surrounded by a hyperechogenic rim. Technical feasibility and accuracy were assessed in six additional pig cadavers by injecting 0.15 mL kg⁻¹ methylene blue dye bilaterally in direct proximity to the nerve. The needle was inserted caudoventral to the coxal tuber, traversing the ultrasound plane as it progressed towards the FN in dorsomedial direction. Staining of the nerve was evaluated by dissection. The injection was considered effective if the nerve was stained in its entire circumference over a length of 2 cm. FNs of all investigated individuals could be successfully stained. This ultrasound-guided subiliac approach allows feasible and accurate access to the FN and may be useful in producing a successful blockade in vivo.

A randomised, non-inferiority study of chloroprocaine 2% and ropivacaine 0.75% in ultrasound-guided axillary block

Chloroprocaine is a short-acting local anaesthetic with a rapid onset of action and an anaesthesia duration up to 60 min. In this pivotal study success rates, onset and remission of motor and sensory block and safety of chloroprocaine 2% was compared to ropivacaine 0.75% for short-duration distal upper limb surgery with successful block rates as primary outcome. The study was designed as a prospective, randomised, multi-centre, active-controlled, double-blind, parallel-group, non-inferiority study, performed in 4 European hospitals with 211 patients scheduled for short duration distal upper limb surgery under axillary plexus block anaesthesia. Patients received either ultrasound guided axillary block with 20 ml chloroprocaine 2%, or with 20 ml ropivacaine 0.75%. Successful block was defined as block without any supplementation in the first 45 min calculated from the time of readiness for surgery. 90.8% patients achieved a successful block with chloroprocaine 2% and 92.9% patients with Ropivacaine 0.75%, thus non-inferiority was demonstrated (10% non inferiority margin; 95% CI − 0.097, 0.039; p = 0.02). Time to onset of block was not significantly different between the groups. Median time to motor and sensory block regression was significantly shorter as was time to home discharge (164 [155–170] min for chloroprocaine versus 380 [209–450] for the ropivacaine group, p < 0.001). For short-duration surgical procedures, the short-acting Chloroprocaine 2% may be used, with success rates non-inferior to ropivacaine and a favourable safety profile.

Trial registration: The trial was registered at Clinicaltrials.gov with registration number NCT02385097 (March 11th, 2015) and European Clinical Trial Database with the EudraCT number 2014-002519-40 (July 7th, 2015, Austria—BASG).

Ultrasound in paediatric anaesthesia - A comprehensive review

The use of ultrasound is becoming more widespread in anaesthesia. In this review, we discuss the use of ultrasound in various aspects of paediatric anaesthesia and how it can be used to assist diagnostic and therapeutic interventions and the evidence available. We explore the use of ultrasound as an adjunct for regional anaesthesia, vascular access, airway management, bedside cardiac, pulmonary and abdominal imaging and intracranial pressure monitoring.

Ultrasound-Guided Peripheral Nerve Blocks Performed by Orthopedic Surgeons: A Retrospective, Multicenter Study in Akita Prefecture, Japan

The shortage of doctors is a societal problem, especially in rural areas such as Akita Prefecture, Japan. Therefore, it is not unusual in Akita for orthopedic surgeons to perform upper and lower limb surgeries under ultrasound-guided peripheral nerve blocks managed by the operators themselves. Multicenter studies of ultrasound-guided peripheral nerve blocks performed by orthopedic surgeons have not been reported. The purpose of this study was to clarify the safety and reliability of ultrasound-guided peripheral nerve blocks performed by orthopedic surgeons in Akita. A total of 1,674 upper extremity surgery cases operated under ultrasound-guided peripheral nerve blocks at 8 hospitals in Akita prefecture from April 2016 to April 2018 were investigated retrospectively. These blocks were performed by a total of 37 orthopedic surgeons, including senior surgeons and residents. In 321 of the 1,674 cases (19%), local anesthetics were added to the surgical field. Two cases with special factors were converted to general anesthesia. There were 2 cases of complications associated with the nerve block, but they were all transient and recovered promptly. The block site and the hospital where the block was performed showed a significant relationship with the addition of local anesthetics to the surgical site (P < 0.001). Surgery time, age at surgery, and surgical site showed no significant relationships with the addition of local anesthetics. The volume of the anesthetic used for the nerve block showed a significant inverse relationship with the addition of local anesthetics (P=0.040). Many orthopedic surgeons in Akita prefecture began to perform ultrasound-guided peripheral nerve blocks, which had a reliable anesthesia effect with no noticeable complications, whether performed by residents or senior orthopedic surgeons, and this is a useful anesthetic technique for orthopedic surgeons.

European Society of Anaesthesiology and Intensive Care Guidelines on peri-operative use of ultrasound for regional anaesthesia (PERSEUS regional anesthesia): Peripheral nerves blocks and neuraxial anaesthesia

Nowadays, ultrasound-guidance is commonly used in regional anaesthesia (USGRA) and to locate the spinal anatomy in neuraxial analgesia. The aim of this second guideline on the PERi-operative uSE of UltraSound (PERSEUS-RA) is to provide evidence as to which areas of regional anaesthesia the use of ultrasound guidance should be considered a gold standard or beneficial to the patient. The PERSEUS Taskforce members were asked to define relevant outcomes and rank the relative importance of outcomes following the GRADE process. Whenever the literature was not able to provide enough evidence, we decided to use the RAND method with a modified Delphi process. Whenever compared with alternative techniques, the use of USGRA is considered well tolerated and effective for some nerve blocks but there are certain areas, such as truncal blocks, where a lack of robust data precludes useful comparison. The new frontiers for further research are represented by the application of USG during epidural analgesia or spinal anaesthesia as, in these cases, the evidence for the value of the use of ultrasound is limited to the preprocedure identification of the anatomy, providing the operator with a better idea of the depth and angle of the epidural or spinal space. USGRA can be considered an essential part of the curriculum of the anaesthesiologist with a defined training and certification path. Our recommendations will require considerable changes to some training programmes, and it will be necessary for these to be phased in before compliance becomes mandatory.

Patient satisfaction with intravenous regional anaesthesia or an axillary block for minor ambulatory hand surgery: A randomised controlled study

BACKGROUND

Intravenous regional anesthesia (IVRA) and the axillary brachial plexus block are popular alternatives to general anaesthesia in ambulatory hand surgery. Although both have proven their effectiveness, patients' preferences have never been evaluated.

OBJECTIVES

We investigated patient satisfaction with both techniques and hypothesised that satisfaction after IVRA is noninferior compared with axillary brachial plexus block.

DESIGN

A prospective, randomised controlled trial.

SETTING

Ambulatory surgical day care centre, University Hospitals of Leuven, Belgium, from September 2016 to November 2017.

PATIENTS

One hundred and twenty adults undergoing minor ambulatory hand surgery were included in this study.

INTERVENTION

Patients received either IVRA with 300 mg lidocaine or an axillary block with 280 mg mepivacaine.

MAIN OUTCOME MEASURES

The primary endpoint was the evaluation of patient satisfaction using the 'Evaluation du Vécu de l'Anésthesie Locoregional' (EVAN-LR) questionnaire. Secondary outcomes included different procedural times, block quality, tourniquet discomfort, the incidence of block failure and postoperative nausea and vomiting (PONV), the severity of postoperative pain and the need for postoperative analgesics during the first 24 h.

RESULTS

Noninferiority of IVRA was shown for the median [IQR] total score on the EVAN-LR questionnaire, IVRA-group: 92 [87 to 96] vs. axillary brachial plexus block-group: 91[87 to 97]; Hodges--Lehmann estimator (95% confidence interval (CI)] for the shift: -0.25 (-2.60 to 2.20). Induction of anaesthesia and time to discharge, requiring partial recovery of the motor block, were significantly longer in the axillary brachial plexus block group. The IVRA-group had a lower block quality, a higher incidence of tourniquet-discomfort and higher median intra-operative and postoperative pain scores on day 0; 0 [0 to 2] vs. 0 [0 to 0] and 0.8 [0 to 1.8] vs. 0 [0 to 0.25], respectively, but no increase in the need for supplementary analgesics or conversion rate to general anaesthesia.

CONCLUSION

IVRA and axillary brachial plexus block result in comparably high patient satisfaction in ambulatory hand surgery.

CLINICAL TRIAL REGISTRATION

EudraCT 2016-002325-11.

Onset times and duration of analgesic effect of various concentrations of local anesthetic solutions in standardized volume used for brachial plexus blocks

Visualization of the nerve structures of brachial plexus allows anesthesiologists to use a lower dose of local anesthetics. The content of this low dose is not unequivocal, consequently, the pharmacokinetics of local anesthetics used by various authors are difficult to compare. In this study, the onset times and duration of the analgesic effect of local anesthetic mixture solutions used for brachial plexus blocks are investigated and the quality of anesthesia is compared. 85 unpremedicated American Society of Anesthesiologist physical status I-III, 19-83-year-old patients scheduled for upper limb trauma surgery are assigned to four groups for the axillary-supraclavicular block with lidocaine 1% and bupivacaine 0,5% 1:1 mixture (Group LB) or bupivacaine 0.33% (Group BS) or lidocaine 0,66% (Group LS) or bupivacaine 0.5% and lidocaine 1% 2:1 mixture (Group BL). 0.4 ml/kg was administered to the four groups. The onset time was significantly shorter in the lidocaine group (LS 13.0 ± 1.02) than in the other study groups (LB 16.64 ± 0.89; BS 17.21 ± 0.74; BL 16.92 ± 0.51 min ±SEM, p = 0.002). No differences were observed in the onset times between LB, BS, and BL groups (p > 0.05). Statistical differences were found in the duration of local anesthetics between LB (392.9 ± 20.4), BS (546.4 ± 14.9), LS (172.85 ± 7.8), and BL (458.7 ± 11.9 min ±SEM, p = 0.001). Lidocaine does not shorten the onset times, but significantly decreases the duration of action of bupivacaine when used in mixture solutions. Lidocaine exhibits a good quality of block in the applied dose, while other solutions have excellent quality. Bupivacaine without lidocaine has the longest duration of action to achieve the longest postoperative analgesia.

Efficacy of Regional Anesthesia in Secondary Procedures or Revisions of Arteriovenous Fistula

BACKGROUND

Several factors affect the outcomes of arteriovenous fistula (AVF) and end-stage renal disease (ESRD). This study aimed to evaluate the efficacy of regional anesthesia in secondary procedures or revisions of AVF.

METHODS

Medical records of patients who underwent treatment for AVF secondary procedures or revisions under brachial plexus block (BPB) between March 2016 and June 2019 were retrospectively analyzed. Patient characteristics and clinical outcomes were evaluated.

RESULTS

In total, 375 patients (mean age 65.6 ± 12.74; males 210, 56.0%) were enrolled in the study and 770 procedures were performed under BPB for AVF secondary procedures or revisions. The procedures included endovascular treatment (385, 50.0%), surgical treatment (105, 13.6%), and hybrid treatment (280, 36.4%). In 180 procedures (23.4%) for AVF lesions, the operative field included a single segment of the arm, whereas in 590 procedures (76.6%), the operative field included multiple segments. In total, 37 (4.8%) cases of 30-day postoperative complications were observed, of which 33 (4.3%) were surgery-related complications, 2 (0.3%) were BPB-related complications (neurapraxia), and 2 (0.3%) were contrast agent allergic reactions; 34 (4.4%) reinterventions of the total 201 (26.1%) reinterventions were performed within 30 days postoperatively. The mean operation time was 87.5 ± 55.35 min. The pain score for all patients was 0 (no pain), and no patient demanded opioids postoperatively.

CONCLUSIONS

Ultrasound-guided BPB is safe and effective for AVF secondary procedures or revisions in ESRD patients.

Evaluation of magnesium as an adjuvant to ropivacaine-induced axillary brachial plexus block: A prospective, randomised, double-blind study

Background and Aims:

Axillary brachial plexus block is commonly performed for surgeries on the hand and forearm. However, there are very few studies on the use of magnesium sulphate in axillary brachial plexus block and, hence, the study was designed to evaluate magnesium as an adjuvant to ropivacaine-induced axillary block with respect to onset and duration of sensorimotor block and postoperative analgesia.

Methods:

Sixty patients of the American Society of Anesthesiologists (ASA) physical status I and II, undergoing surgeries on the hand and forearm were randomly recruited to receive ultrasound-guided axillary block with either 150 mg magnesium sulphate or 1 mL normal saline added to 0.5% ropivacaine. The primary outcome measure was to compare block characteristics including postoperative analgesia and the secondary outcome was to compare the use of rescue analgesia and the side-effect profile. Data were statistically analysed using Statistical Package for Social Sciences (SPSS version 21.0). Categorical variables were compared using the Chi-square test or Fisher's exact probability test; continuous variables compared using unpaired t-test or Mann-Whitney U test.

Results:

Onset of sensory (9.93 ± 1.31 vs 8.83 ± 1.12 min) as well as motor block (13.37 ± 1.63 vs 11.57 ± 1.30 min) was significantly hastened with addition of magnesium to ropivacaine (p < 0.001) and so was the duration (sensory 386.60 ± 18.26 vs 526.37 ± 27.43, motor 323.73 ± 15.17 vs 436.97 ± 18.99 min) (p < 0.001) and postoperative analgesia (425 ± 21.39 vs 572.83 ± 32.04 min) (p < 0.001) which reflected in decreased requirement of rescue analgesic and total postoperative analgesic dosage.

Conclusions:

Magnesium is an effective and safe adjuvant to local anaesthetics and improves all characteristics of axillary brachial plexus block along with postoperative analgesia.

Efficacy of Nalbuphine as an Adjuvant to Ropivacaine in Ultrasound-guided Supraclavicular Brachial Block: A Prospective Randomized Controlled Study

BACKGROUND

A brachial plexus block (BPB) provides anesthesia and analgesia with limited duration. Various opioids have been used as adjuvants of local anesthetics to improve the effects.

OBJECTIVE

The objective of this study was to evaluate the safety and effectiveness of nalbuphine used as an adjuvant to local anesthetic during the supraclavicular BPB.

MATERIALS AND METHODS

In this prospective, double-blinded, randomized controlled study, 90 American Society of Anesthesiology (ASA) Physical Status I and II patients (aged 20 to 65 y) of either sex undergoing upper limb orthopedic surgeries under ultrasound-guided supraclavicular BPB were randomly allocated into 3 groups: group C (n=30), group NL (n=30), and group NH (n=30) for analyses. Each patient received 18 mL of 100 mg ropivacaine solution combined with 2 mL of normal saline, 2 mL of 10 mg nalbuphine, or 2 mL of 20 mg nalbuphine. The time of onset and block duration of sensory block (SB) and motor block (MB), duration of analgesia, hemodynamic variables, and any adverse effects were assessed.

RESULTS

Compared with group C, the onset time of both SB and MB were significantly shortened. The SB and MB duration were significantly prolonged in group NL and group NH. There was no significant difference between the duration of analgesia in group NL and NH although the analgesia duration of both groups was longer than group C. But the incidence of side effects in group NH such as vomiting was significantly higher than group NL.

CONCLUSIONS

Nalbuphine is an effective adjuvant to 0.5% ropivacaine in ultrasound-guided supraclavicular BPB. The dosage of 10 mg improves the quality of the anesthesia with less incidence of side effects.

Ultrasonographic study of a modified axillary approach to block the major branches of the brachial plexus in dogs

OBJECTIVE

To provide ultrasonographic mapping of the axillary region of dogs to facilitate identification of the major branches of the brachial plexus in relation to the axillary artery.

STUDY DESIGN

Prospective study.

ANIMALS

A total of two dog cadavers and 50 client-owned, healthy dogs weighing >15 kg.

METHODS

In Phase 1, anatomical dissections were performed to identify the relation of the major brachial plexus nerves to the axillary artery. In Phase 2, with the dogs in dorsal recumbency with thoracic limbs flexed naturally, the axillary space was scanned using a linear array probe oriented on the parasagittal plane until the axis transverse to nerves was found. Then, the transducer was rotated to a slight lateral angle approximately 30° to midline. The examination aimed to identify the axillary artery and the musculocutaneous, radial, median and ulnar nerves in addition to determining their position and distribution in four predefined sectors.

RESULTS

The musculocutaneous nerve was observed in all animals cranial to the axillary artery. The radial, ulnar and median nerves were distributed around the axillary artery, with >90% on the caudal aspect of the axillary artery (sectors 1 and 2).

CONCLUSIONS AND CLINICAL RELEVANCE

Ultrasonography identified the location of the brachial plexus nerves near the studied sectors, providing useful guidance for performing a brachial plexus nerve block.

Combined ultrasound and nerve stimulator-guided deep nerve block may decrease the rate of local anesthetics systemic toxicity: a randomized clinical trial

Background

Ultrasound guidance might decrease the incidence of local anesthetics systemic toxicity (LAST) for many peripheral nerve blocks compared with nerve stimulator guidance. However, it remains uncertain whether ultrasound guidance is superior to nerve stimulator guidance for deep nerve block of the lower extremity. This study was designed to investigate whether deep nerve block with ultrasound guidance would decrease the incidence of LAST compared with that with nerve stimulator guidance, and to identify associated risk factors of LAST.

Methods

Three hundred patients undergoing elective lower limb surgery and desiring lumbar plexus blocks (LPBs) and sciatic nerve blocks (SNBs) were enrolled in this study. The patients were randomly assigned to receive LPBs and SNBs with ultrasound guidance (group U), nerve stimulator guidance (group N) or dual guidance (group M). The primary outcome was the incidence of LAST. The secondary outcomes were the number of needle redirection, motor and sensory block onset and nerve distribution restoration time, as well as associated risk factors.

Results

There were 18 patients with LAST, including 12 in group U, 4 in group N and 2 in group M. By multiple comparisons among the three groups, we found that the incidence of LAST in group U (12%) was significantly higher than that in group N (4%)(P = 0.037) and group M(2%)(P = 0.006). The OR of LAST with hepatitis B (HBV) infection and the female sex was 3.352 (95% CI,1.233–9.108, P = 0.013) and 9.488 (95% CI,2.142–42.093, P = 0.0004), respectively.

Conclusions

Ultrasound guidance, HBV infection and the female sex were risk factors of LAST with LPBs and SNBs. For patients infected with HBV or female patients receiving LPBs and SNBs, we recommended that combined ultrasound and nerve stimulator guidance should be used to improve the safety.

Trial registration

This study was approved by the Ethical Committee of the First Affiliated Hospital of Army Medical University. The protocol was registered prospectively with the Chinese Clinical Trial Registry (ChiCTR-IOR-16008099) on March 15, 2016.

Ultrasound Guidance Enhances the Efficiency of Brachial Plexus Block and Ameliorates the Vascular Injury Compared with Nerve Stimulator Guidance in Hand Surgery Patients

Background: Nerve stimulation guidance and ultrasound guidance are two major methods that have been widely accepted and applied in axillary brachial plexus block. However, the differences between the effects of these two types of guidance still need to be further elucidated for clinical usage. Materials and Methods: Overall, 208 patients undergoing elective upper limb surgeries and receiving axillary brachial plexus block were recruited in our study. The patients were randomly assigned to receive either ultrasound guidance (group U, n = 112) or nerve stimulation (group N, n = 96). Pinprick test was performed for assessing the sensory blockades. The pain was evaluated by visual analog scale (VAS). Reactive oxygen species (ROS) levels were measured by dichloro-dihydro-fluorescein diacetate staining and serum levels of nitric oxide (NO), nitric oxide synthases (NOS), tumor necrosis factor (TNF)-α, and monocyte chemoattractant protein 1 (MCP1) were evaluated by ELISA. Results: Ultrasound guidance significantly enhanced the quality of the sensory blockade and reduced the VAS scores when compared with the nerve stimulator guidance. In addition, the production of ROS, NO, NOS, TNF-α, and MCP-1 were significantly alleviated by ultrasound guidance. Conclusion: Ultrasound-guided brachial plexus block relieves pain during operation, provides higher success rates in the nerve block, causes less vascular damage and results in lower levels of inflammatory cytokines secretion when compared with neurostimulator-directed brachial plexus blockage.

A Comparative Clinical Study of Ultrasonography-Guided Perivascular and Perineural Axillary Brachial Plexus Block for Upper Limb Surgeries

Background:

Axillary brachial plexus block (ABPB) is safest among other methods of brachial plexus block because of its ease and reliability. The two approaches of ultrasonography-guided ABPB are perivascular (PV) and perineural (PN).

Aims:

This study was conducted to compare primary outcomes such as performance time, onset of the block, number of needle passes, block success rate, duration of sensory and motor block, and complications between ultrasound-guided PV and PN ABPB in patients posted for upper limb surgeries.

Settings and Design:

This prospective randomized study was conducted on 106 patients American Society of Anesthesiologists Class I and II posted for forearm, wrist, and hand surgeries, who were allotted into Group PV and Group PN 53 each.

Materials and Methods:

In both methods, 20 mL of the drug was used. To start with, musculocutaneous nerve was blocked with 5 mL of the drug. In the PV technique, remaining 15 mL of the drug was deposited anterior and posterior to axillary artery, and in PN technique, 5 mL of the drug was injected around radial, ulnar, and median nerve.

Statistical Analysis:

Mann–Whitney and Chi-square test were used for statistical analysis.

Results:

Significant difference was observed between the two groups in performance time (PV – 8.647 ± 0.54 min and PN – 14.53 ± 0.20 min), onset time (PV – 19.48 ± 2.83 min and PN – 13.86 ± 1.81 min), and number of needle passes (PV – 2.30 ± 0.50 and PN – 4.91 ± 0.66). Other parameters were comparable in both the groups.

Conclusions:

Ultrasound-guided PV axillary plexus block is better than PN axillary plexus block with respect to performance time and number of needle passes; but onset time was shorter in PN block, with precaution eliminating the risk of complications.

Establishing an Acute Pain Service in Private Practice and Updates on Regional Anesthesia Billing

Acute pain management is an expanding perioperative specialty and there is a renewed focus on implementing and developing an acute pain service (APS) in nonacademic hospitals (ie, "private practice"). An anesthesiologist-led APS can improve patient care by decreasing perioperative morbidity and potentially reducing the risk of chronic postsurgical pain syndromes. Elements of a successful APS include multidisciplinary collaboration to develop perioperative pain protocols, education of health care providers and patients, and regular evaluation of patient safety and quality of care metrics. Standardization of regional anesthesia procedures and billing practices can promote consistent outcomes and efficiency.

Nerve detection during surgery: optical spectroscopy for peripheral nerve localization

Precise nerve localization is of major importance in both surgery and regional anesthesia. Optically based techniques can identify tissue through differences in optical properties, like absorption and scattering. The aim of this study was to evaluate the potential of optical spectroscopy (diffuse reflectance spectroscopy) for clinical nerve identification in vivo. Eighteen patients (8 male, 10 female, age 53 ± 13 years) undergoing inguinal lymph node resection or resection or a soft tissue tumor in the groin were included to measure the femoral or sciatic nerve and the surrounding tissues. In vivo optical measurements were performed using Diffuse Reflectance Spectroscopy (400-1600 nm) on nerve, near nerve adipose tissue, muscle, and subcutaneous fat using a needle-shaped probe. Model-based analyses were used to derive verified quantitative parameters as concentrations of optical absorbers and several parameters describing scattering. A total of 628 optical spectra were recorded. Measured spectra reveal noticeable tissue specific characteristics. Optical absorption of water, fat, and oxy- and deoxyhemoglobin was manifested in the measured spectra. The parameters water and fat content showed significant differences (P < 0.005) between nerve and all surrounding tissues. Classification using k-Nearest Neighbor based on the derived parameters revealed a sensitivity of 85% and a specificity of 79%, for identifying nerve from surrounding tissues. Diffuse Reflectance Spectroscopy identifies peripheral nerve bundles. The differences found between tissue groups are assignable to the tissue composition and structure.

Comparison Between the Two-Injection Technique and the Four-Injection Technique in Axillary Brachial Plexus Block with Articaine

Objective

In this study, we aimed to compare axillary brachial plexus block using the two-injection and four-injection techniques assisted with ultrasonography (USG) and nerve stimulator in patients operated for carpal tunnel syndrome with articaine. To evaluate which technique is more effective, we compared the onset time, effectiveness, and duration of block procedures, patient satisfaction, adverse effect of the drug, and complication rates of the motor and sensory blocks.

Methods

Sixty patients were randomly divided into two groups. A mixture of physiologic serum added to articain with NaHCO₃ (30 mL) was injected into the patients' axilla in both the groups. After the blockage of the musculocutaneous nerve in both the groups, the median nerve in the two-injection group and the median nerve, ulnar nerve, and radial nerve in the four-injection group were blocked. In brachial plexus nerves, sensorial blockage was evaluated with pinprick test, and motor block was evaluated by contraction of the muscles innervated by each nerve. The adverse effects and complications, visual analog scale (VAS) values during the operation, and post-operative patient satisfaction were recorded.

Results

Sufficient analgesia and anaesthesia were achieved with no need for an additional local anaesthetics in both the groups. Furthermore, additional sedation requirements were found to be similar in both the groups. A faster rate and a more effective complete block were achieved in more patients from the four-injection group. In the two-injection group, the block could not be achieved for N. radialis in one patient. All other nerves were successfully blocked. Whereas the blockage procedure lasted longer in the four-injection group, the VAS values recorded during the blockage procedure were higher in the four-injection group. No statistical difference was found with regard to patient satisfaction, and no adverse effects and complications were observed in any group.

Conclusion

Although the multi-injection method takes more time, it provides faster anaesthesia and more complete blockage than the two-injection method used with articain. The two-injection method can also be used in specific surgery such as for carpal tunnel syndrome, as an alternative to multi-injection method.

Evaluation of the relationship between the topographical anatomy in the axillary region of the brachial plexus and the body mass index

To investigate the topographic anatomy of the median, musculocutaneous, radial and ulnar nerves with respect to the axillary artery and to seek whether these configurations are associated with baseline descriptive data including age, gender, and body-mass index. This cross-sectional trial was carried out on 199 patients (85 women, 114 men; average age: 46.78 ± 15.45 years) in the department of anaesthesiology and reanimation of a tertiary care center. Topographic anatomy of the median, musculocutaneous, radial and ulnar nerves was assessed with ultrasonography. Localization of these nerves with respect to the axillary artery was marked on the map demonstrating 16 zones around the axillary artery. Frequencies of localizations of every nerve in these zones were recorded, and the correlation of these locations with descriptive data including age, gender and BMI was investigated. There was no difference between women and men for the distribution of the median (p = 0.74), ulnar (p = 0.35) and radial (p = 0.64) nerves. However, the musculocutaneous nerve was more commonly located in Zone A13 in men compared to women (p = 0.02). The localization of the median (p = 0.85), ulnar (p = 0.27) and radial (p = 0.88) nerves did not differ remarkably between patients with BMI < 25 kg/m² and patients with BMI ≥ 25 kg/m². Notably, the musculocutaneous nerve was more often determined in Zone A10 in cases with BMI ≥ 25 kg/m² (p = 0.001). Our results imply that the alignment of the musculocutaneous nerve may vary in men and overweight people. This fact must be considered by the anaesthetist before planning the axillary block of brachial plexus. All these informations may enlighten the planning stages of the brachial plexus blockade.

Efficacy of ultrasound and nerve stimulation guidance in peripheral nerve block: A systematic review and meta-analysis

Evidence was controversial about whether nerve stimulation (NS) can optimize ultrasound guidance (US)-guided nerve blockade for peripheral nerve block. This review aims to explore the effects of the two combined techniques. We searched EMBASE (from 1974 to March 2015), PubMed (from 1966 to Mar 2015), Medline (from 1966 to Mar 2015), the Cochrane Central Register of Controlled Trials and clinicaltrials.gov. Finally, 15 randomized trials were included into analysis involving 1,019 lower limb and 696 upper limb surgery cases. Meta-analysis indicated that, compared with US alone, USNS combination had favorable effects on overall block success rate (risk ratio [RR] 1.17; confidence interval [CI] 1.05 to 1.30, P = 0.004), sensory block success rate (RR 1.56; CI 1.29 to 1.89, P < 0.00001), and block onset time (mean difference [MD] -3.84; CI -5.59 to -2.08, P < 0.0001). USNS guidance had a longer procedure time in both upper and lower limb nerve block (MD 1.67; CI 1.32 to 2.02, P < 0.00001; MD 1.17; CI 0.95 to 1.39, P < 0.00001) and more patients with anesthesia supplementation (RR 2.5; CI 1.02 to 6.13, P = 0.05). USNS guidance trends to result in a shorter block onset time than US alone as well as higher block success rate, but no statistical difference was demonstrated, as more data are required. © 2017 IUBMB Life, 69(9):720-734, 2017.