Evidence Basis for the Use of Ultrasound for Upper-Extremity Blocks:

Ultrasound-Guided peripheral nerve blocks for major amputation in critically ill patients with peripheral artery disease

OBJECTIVE

The aim of this study was to assess the safety and efficacy of major amputation under ultrasound-guided peripheral nerve blocks in critical peripheral artery disease (PAD) patients.

METHODS

We reviewed the medical records of consecutive patients who underwent major amputation at our center between December 2012 and December 2020. The patients' baseline demographics and comorbidities were collected. The primary outcomes were 30-day and 12-month mortality. The secondary outcomes were intraoperative events, complications and intensive care unit (ICU) admission.

RESULTS

Fifteen patients classified as American Society of Anesthesiologist (ASA) III and 13 ASA IV (mean age: 76.07 ± 11.78 years) were included in the study. These patients were critically ill and had many comorbidities, such as coronary artery disease. All amputations were successfully performed under ultrasound-guided PNB without conversion to GA, but intravenous analgesia was given in 7 patients during the operation. The majority of the patients had stable hemodynamics except for 2 patients who had hypoxia, so none of the patients were transferred to the ICU postoperatively. None of the patients suffered from acute cardio-cerebral events. However, 5 patients had wound infections, and 4 of 5 patients had to receive reamputation. None of the patients died within 48 h after amputation. However, the 30-day mortality was 3.57%, and the 12-month mortality was up to 35.71%.

CONCLUSION

This study demonstrates that major amputation could be safely and effectively performed under ultrasound-guided peripheral nerve blocks for critically ill patients, and ultrasound-guided peripheral nerve blocks could be an alternative for patients at high risk of general anesthesia or spinal anesthesia.

A prospective, randomised, single-blinded controlled trial comparing ultrasound versus nerve stimulator guidance for interscalene block for ambulatory upper limb surgeries

Background

Interscalene block is usually performed using either ultrasound (US) or nerve stimulator (NS) guidance. This single-blinded, prospective, randomised study was performed to find out whether US was able to offer distinct advantages over conventional NS guidance.

Methods

100 patients in the American Society of Anaesthesiology (ASA) physical status I to III, aged 18-70 years were randomised into US guided or NS guided group for interscalene block with 15 ml 0.5% bupivacaine and 5 ml 2% lignocaine. Patients were premedicated with midazolam 0.03 mg/kg (maximum 2 mg) and fentanyl 2 mcg/kg (max 100 mcg) was used as rescue analgesia.

Result

Mean time of onset of sensory block in the NS group was 6.2 min (3.1), the US group 4.7 min (1.1), p value (<0.001). Mean duration of post-operative analgesia in NS group 323.6 min (98.6), US group 558.6 min (144.3), (p < 0.001). Mean time for performance of block NS Group 7.3 min (2.0), and in the US group 4.9 min (1.3), (p < 0.001). Number of needle passes NS group 1.7(0.9), US group 1.3 (1.0), (p < 0.005). Total cost per surgery with NS was Rs 363.10 less than in the US-guided block. Incremental cost effectiveness ratio for ultrasound group for onset of block was Rs -242.07, Rs 92.0 for duration of block and Rs -151.29 for time for performance of block. No incident of post-operative neurological complications seen in either group.

Conclusion

Ultrasound use offers faster onset, longer duration of block, reduces time for performance of blocks with comparable complication rates. For most of the measured parameters it was superior but more costly than nerve stimulator for directly measured costs.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound - Part II: Joint Pathologies, Pediatric Applications, and Guided Procedures

The second part of the Guidelines and Recommendations for Musculoskeletal Ultrasound (MSUS), produced under the auspices of EFSUMB, following the same methodology as for Part 1, provides information and recommendations on the use of this imaging modality for joint pathology, pediatric applications, and musculoskeletal ultrasound-guided procedures. Clinical application, practical points, limitations, and artifacts are described and discussed for every joint or procedure. The document is intended to guide clinical users in their daily practice.

Continued Validation of Ultrasound Guidance Targeting Tasks: Relationship with Procedure Performance

RATIONALE AND OBJECTIVES

To determine if deliberative practice with novel ultrasound guidance targeting tasks improves simulated procedural skill.

MATERIALS AND METHODS

In a nonrandomized interventional trial first year medical students practiced the previous described dowel and straw targeting tasks 1 hour a week for 4 weeks (training group) or had no training (controls). Afterward, they each performed a simulated amniocentesis (AMN) and chorionic villus sampling (CVS) procedure. Procedures were scored using a global rating scale (GRS) and compared between groups with Mann-Whitney U tests. Two-way random effects intraclass correlation coefficients for the inter- and intra-rater variability were calculated for each item in both GRS's.

RESULTS

The training group (n = 22) had higher scores on several aspects and overall performance of AMN compared to controls (n = 15). There were no differences between groups for CVS. The inter-rater and intra-rater reliability of the GRS's for both AMN and CVS ranged from 0.16 to 0.89 with most values demonstrating good to excellent agreement.

CONCLUSION

This study demonstrates validity evidence in the content and internal structure domains for the AMN and CVS simulators and their accompanying GRS's. Repetitive practice of the targeting tasks improved student performance in simulated AMN, but modifications are needed for it to be relevant to other procedures such as CVS.

A case report: the use of ultrasound guided peripheral nerve block during above knee amputation in a severely cardiovascular compromised patient who required continuous anticoagulation

RATIONALE

Although lower-extremity surgeries are mainly performed under general or central neuraxial anesthesia, ultrasound-guided peripheral nerve block (PNB) can be a good alternative, especially for patients who require continuous anticoagulation treatment and present with poor cardiovascular conditions.

PATIENTS CONCERNS

The patient required continuous anticoagulation treatment due to the high risk of thromboembolism and poor cardiovascular conditions.

DIAGNOSES

The patient required lower-extremity amputation due to atherosclerotic and thromboembolic obstruction.

INTERVENTIONS

We decided to progress the operation under peripheral nerve block. The sciatic, femoral, lateral femoral cutaneous nerve and anterior branch of the obturator nerve were blocked under ultrasound guidance. Sixty ml of a local anesthetic (equal mix of 1% lidocaine and 0.375% ropivacaine) was administered for the block.

OUTCOMES

Sufficient sensory block at the area of amputation was obtained, and the patient's vital signs were stable throughout surgery.

LESSONS

Ultrasound-guided peripheral nerve block can be an excellent anesthetic technique for patients receiving radical surgery at the proximal lower extremities, especially patients who are critically ill and considered high risk.

Ultrasound-Guided Popliteal Sciatic Block Provides Adequate Analgesia During Urgent Endovascular Treatment of Critical Limb Ischemia with Resting Pain

PURPOSE

To demonstrate feasibility and safety of ultrasound-guided popliteal sciatic nerve block for providing analgesia during urgent endovascular treatment of critical limb ischemia with resting pain.

MATERIALS AND METHODS

Ultrasound-guided popliteal sciatic blocks were performed by an interventional radiologist in angiography suite immediately prior to commencement of urgent endovascular treatment of 30 critical limb ischemia patients. Subjective pain levels prior to and following sciatic block were assessed using the visual analog scale (VAS). Need for any supplemental anxiolytics or analgesics during treatment was recorded. Post-procedural evaluation of patient and operator satisfaction levels regarding the intervention was also documented.

RESULTS

Ultrasound-guided sciatic block provided adequate analgesia in all patients; VAS scores were 0 (no pain) in 87% and 1-3 (mild to annoying pain) in 13%. Two patients required anxiolytic premedication. Additional analgesia was not required during course of endovascular treatment of any patients. Time necessary to perform sciatic block ranged 3-9 (mean 5.9 ± 1.3) min. Median number of needle attempts was 1 (range 1-3). Onset of satisfactory block ranged from 5 to 20 min (mean 9.4 ± 2.6 min). Mean treatment time was 102.2 ± 36.7 min, and balloon time was 22.4 ± 6.1 min. Patient and operator satisfaction with pain control were very good in all cases. There were no procedure-related complications.

CONCLUSIONS

Ultrasound-guided popliteal sciatic block is a feasible and safe alternative for providing adequate analgesia during urgent endovascular treatment of critical limb ischemia with resting pain.

LEVEL OF EVIDENCE

Level 4, case series.

Holistic ultrasound in trauma: An update

Holistic ultrasound is a total body examination using an ultrasound device aiming to achieve immediate patient care and decision making. In the setting of trauma, it is one of the most fundamental components of care of the injured patients. Ground-breaking imaging software allows physicians to examine various organs thoroughly, recognize imaging signs early, and potentially foresee the onset or the possible outcome of certain types of injuries. Holistic ultrasound can be performed on a routine basis at the bedside of the patients, at admission and during the perioperative period. Trauma care physicians should be aware of the diagnostic and guidance benefits of ultrasound and should receive appropriate training for the optimal management of their patients. In this paper, the findings of holistic ultrasound in trauma patients are presented, with emphasis on the lungs, heart, cerebral circulation, abdomen, and airway. Additionally, the benefits of ultrasound imaging in interventional anaesthesia techniques such as ultrasound-guided peripheral nerve blocks and central vein catheterization are described.

Phrenic nerve block caused by interscalene brachial plexus block: breathing effects of different sites of injection

Background

Interscalene brachial plexus (ISB) block is often associated with phrenic nerve block and diaphragmatic paresis. The goal of our study was to test if the anterior or the posterior ultrasound guided approach of the ISB is associated with a lower incidence of phrenic nerve blocks and impaired lung function.

Methods

This was a prospective, randomized and single-blinded study of 84 patients scheduled for elective shoulder surgery who fullfilled the inclusion and exclusion critereria. Patients were randomized in two groups to receive either the anterior (n = 42) or the posterior (n = 42) approach for ISB. Clinical data were recorded. In both groups patients received ISB with a total injection volume of 15 ml of ropivacaine 1 %. Spirometry was conducted at baseline (T₀) and 30 min (T₃₀) after accomplishing the block.

Changes in spirometrical variables between T₀ and T₃₀ were investigated by Wilcoxon signed-rank test for each puncture approach. The temporal difference between the posterior and the anterior puncture approach groups were again analyzed by the Wilcoxon-Mann-Whitney test.

Results

The spirometric results showed a significant decrease in vital capacity, forced expiratory volume per second, and maximum nasal inspiratory breathing after the Interscalene brachial plexus block; indicating a phrenic nerve block (p <0.001, Wilcoxon signed-rank). A significant difference in the development of the spirometric parameters between the anterior and the posterior group could not be identified (Wilcoxon-Mann-Whitney test). Despite the changes in spirometry, no cases of dyspnea were reported.

Conclusion

A different site of injection (anterior or posterior) did not show an effect in reducing the cervical block spread of the local anesthetic and the incidence of phrenic nerve blocks during during ultrasound guided Interscalene brachial plexus block. Clinical breathing effects of phrenic nerve blocks are, however, usually well compensated, and subjective dyspnea did not occur in our patients.

Trial registration

German Clinical Trials Register (DRKS number 00009908, registered 26 January 2016).

Nerve localization techniques for peripheral nerve block and possible future directions

BACKGROUND

Ultrasound guidance is now a standard nerve localization technique for peripheral nerve block (PNB). Ultrasonography allows simultaneous visualization of the target nerve, needle, local anesthetic injectate, and surrounding anatomical structures. Accurate deposition of local anesthetic next to the nerve is essential to the success of the nerve block procedure. Due to limitations in the visibility of both needle tip and nerve surface, the precise relationship between needle tip and target nerve is unknown at the moment of injection. Importantly, nerve injury may result both from an inappropriately placed needle tip and inappropriately placed local anesthetic. The relationship between the block needle tip and target nerve is of paramount importance to the safe conduct of peripheral nerve block.

METHODS

This review summarizes the evolution of nerve localization in regional anesthesia, characterizes a problem faced by clinicians in performing ultrasound-guided nerve block, and explores the potential technological solutions to this problem.

RESULTS

To date, technology newly applied to PNB includes real-time 3D imaging, multi-planar magnetic needle guidance, and in-line injection pressure monitoring. This review postulates that optical reflectance spectroscopy and bioimpedance may allow for accurate identification of the relationship between needle tip and target nerve, currently a high priority deficit in PNB techniques.

CONCLUSIONS

Until it is known how best to define the relationship between needle and nerve at the moment of injection, some common sense principles are suggested.

Evidence-based medicine for ultrasound-guided regional anesthesia

Available evidence favoring the use of ultrasound for regional anesthesia is reviewed, updated, and critically assessed. Important outcome advantages include decreased time to block onset; decreased risk of local anesthetic systemic toxicity; and, depending on the outcome definition, increased block success rates. Ultrasound guidance, peripheral nerve blocks, and central neuraxial blocks are discussed.

Peripheral nerve blocks for ambulatory surgery

Peripheral nerve blocks (PNBs) provide significant improvement in postoperative analgesia and quality of recovery for ambulatory surgery. Use of continuous PNB techniques extend these benefits beyond the limited duration of single-injection PNBs. The use of ultrasound guidance has significantly improved the overall success, efficiency, and has contributed to the increased use of PNBs in the ambulatory setting. More recently, the use of ultrasound guidance has been demonstrated to decrease the risk of local anesthetic systemic toxicity. This article provides a broad overview of the indications and clinically useful aspects of the most commonly used upper and lower extremity PNBs in the ambulatory setting. Emphasis is placed on approaches that can be used for single-injection PNBs and continuous PNB techniques.

Ultrasound-guided Multilevel Paravertebral Blocks and Total Intravenous Anesthesia Improve the Quality of Recovery after Ambulatory Breast Tumor Resection

Background:

Regional anesthesia improves postoperative analgesia and enhances quality of recovery (QoR) after ambulatory surgery. This randomized, double-blinded, parallel-group, placebo-controlled trial examines the effects of multilevel ultrasound-guided paravertebral blocks (PVBs) and total intravenous anesthesia on QoR after ambulatory breast tumor resection.

Methods:

Sixty-six women were randomized to standardized general anesthesia (control group) or PVBs and propofol-based total intravenous anesthesia (PVB group). The PVB group received T1–T5 PVBs with 5 ml of 0.5% ropivacaine per level, whereas the control group received sham subcutaneous injections. Postoperative QoR was designated as the primary outcome. The 29-item ambulatory QoR tool was administered in the preadmission clinic, before discharge, and on postoperative days 2, 4, and 7. Secondary outcomes included block success, pain scores, intra- and postoperative morphine consumption, time to rescue analgesia, incidence of nausea and vomiting, and hospital discharge time.

Results:

Data from sixty-four patients were analyzed. The PVB group had higher QoR scores than control group upon discharge (146 vs. 131; P &lt; 0.0001) and on postoperative day 2 (145 vs. 135; P = 0.013); improvements beyond postoperative day 2 lacked statistical significance. None of the PVB group patients required conversion to inhalation gas–based general anesthesia or experienced block-related complications. PVB group patients had improved pain scores on postanesthesia care unit admission and discharge, hospital discharge, and postoperative day 2; their intraoperative morphine consumption, incidence of nausea and vomiting, and discharge time were also reduced.

Conclusion:

Combining multilevel PVBs with total intravenous anesthesia provides reliable anesthesia, improves postoperative analgesia, enhances QoR, and expedites discharge compared with inhalational gas- and opioid-based general anesthesia for ambulatory breast tumor resection.

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.

Brachial plexus anesthesia: A review of the relevant anatomy, complications, and anatomical variations

The trend towards regional anesthesia began in the late 1800s when William Halsted and Richard Hall experimented with cocaine as a local anesthetic for upper and lower limb procedures. Regional anesthesia of the upper limb can be achieved by blocking the brachial plexus at varying stages along the course of the trunks, divisions, cords and terminal branches. The four most common techniques used in the clinical setting are the interscalene block, the supraclavicular block, the infraclavicular block, and the axillary block. Each approach has its own unique set of advantages and indications for use. The supraclavicular block is most effective for anesthesia of the mid-humerus and below. Infraclavicular blocks are useful for procedures requiring continuous anesthesia. Axillary blocks provide effective anesthesia distal to the elbow, and interscalene blocks are best suited for the shoulder and proximal upper limb. The two most common methods for localizing the appropriate nerves for brachial plexus blocks are nerve stimulation and ultrasound guidance. Recent literature on brachial plexus blocks has largely focused on these two techniques to determine which method has greater efficacy. Ultrasound guidance has allowed the operator to visualize the needle position within the musculature and has proven especially useful in patients with anatomical variations. The aim of this study is to provide a review of the literature on the different approaches to brachial plexus blocks, including the indications, techniques, and relevant anatomical variations associated with the nerves involved.

Pulse transit time as a quick predictor of a successful axillary brachial plexus block

BACKGROUND

It can take up to 30 min to determine whether or not axillary block has been successful. Pulse transit time (PTT) is the time between the R-wave on electrocardiography (ECG) and the arrival of the resulting pressure pulse wave in the fingertip measured with photoplethysmography. It provides information about arterial resistance. Axillary block affects vasomotor tone causing loss of sympathetic vasoconstriction resulting in an increased PTT. Early objective assessment of a block can improve efficacy of operating room time and minimize patient's fear of possible conversion to general anesthesia. This study explores whether PTT can objectively, reliably and quickly predict a successful axillary block.

METHODS

Forty patients undergoing hand surgery under axillary block were included. A three-lead ECG and photoplethysmographic sensors were placed on both index fingers. Measurements were made from 2 min before until 30 min after induction of the block or less if the patient was transferred for operation. Afterwards, PTT was calculated as the time between the R-wave on ECG and a reference point on the photoplethysmogram. To assess the change in PTT caused by the block, the PTT difference between the control and blocked arm was calculated. Sensitivity and specificity of PTT difference were calculated using receiver operating characteristic analysis.

RESULTS

In a successful block, the mean PTT difference significantly increased after 3 min by 12 (standard error of the mean 3.9) ms, sensitivity 87% and specificity 71% (area under the curve 0.87, P = 0.004).

CONCLUSIONS

PTT is a reliable, quick and objective method to assess whether axillary block is going to be successful or not.

Regional blockade of the shoulder: approaches and outcomes

The article reviews the current literature regarding shoulder anesthesia and analgesia. Techniques and outcomes are presented that summarize our present understanding of regional anesthesia for the shoulder. Shoulder procedures producing mild to moderate pain may be managed with a single-injection interscalene block. However, studies support that moderate to severe pain, lasting for several days is best managed with a continuous interscalene block. This may cause increased extremity numbness, but will provide greater analgesia, reduce supplemental opioid consumption, improve sleep quality and patient satisfaction. In comparison to the nerve stimulation technique, ultrasound can reduce the volume of local anesthetic needed to produce an effective interscalene block. However, it has not been shown that ultrasound offers a definitive benefit in preventing major complications. The evidence indicates that the suprascapular and/or axillary nerve blocks are not as effective as an interscalene block. However in patients who are not candidates for the interscalene block, these blocks may provide a useful alternative for short-term pain relief. There is substantial evidence showing that subacromial and intra-articular injections provide little clinical benefit for postoperative analgesia. Given that these injections may be associated with irreversible chondrotoxicity, the injections are not presently recommended.

Analgesic efficacy of ultrasound-guided regional anesthesia: a meta-analysis

STUDY OBJECTIVE

To determine if the use of ultrasound guidance (vs non-ultrasound techniques) improves the success rate of nerve blocks.

DESIGN

Meta-analysis of randomized controlled trials (RCTs) in the published literature.

SETTING

University medical center.

MEASUREMENTS

16 RCTs of patients undergoing elective surgical procedures were studied. Patients underwent ultrasound-guided or non-ultrasound techniques (nerve stimulation, surface landmark) for peripheral nerve blocks. Success rates were measured.

MAIN RESULTS

Ultrasound guidance (vs all non-ultrasound techniques) was associated with a significant increase in the success rate of nerve blocks [relative risk (RR) = 1.11 (95% confidence interval [CI]: 1.06 to 1.17, P < 0.0001]). When compared with nerve stimulator techniques only, ultrasound guidance was still associated with an increase in the success rate (RR = 1.11 [95% CI: 1.05 to 1.17, P = 0.0001]). For specific blocks, ultrasound guidance (vs all non-ultrasound) was associated with a significant increase in successful brachial plexus (all) nerve blocks (RR = 1.11 [95% CI: 1.05 to 1.20, P = 0.0001]), sciatic popliteal nerve block (RR = 1.22 [95% CI: 1.08 to 1.39, P = 0.002]) and brachial plexus axillary nerve block (RR = 1.13 [95% CI: 1.00 to 1.26, P = 0.05]) but not brachial plexus infraclavicular nerve block (RR = 1.25 [95% CI: 0.88 to 1.76, P = 0.22]).

CONCLUSIONS

Ultrasound-guided peripheral nerve block is associated with an increased overall success rate when compared with nerve stimulation or other methods. Ultrasound-guided techniques also increase the success rate of some specific blocks.

[Ultrasound-guided interscalene block in a patient with supraclavicular anatomical abnormalities due to radiotherapy and surgery]

Regional blocks can be difficult in surgical patients with certain superficial anatomical abnormalities. Such blocks may be possible, however, under ultrasound guidance. We report a case in which a man with a fractured right humerus required an ultrasound-guided interscalene brachial plexus block. Secondary to radiotherapy, the patient had right cervical and facial abnormalities that had altered the location of external anatomical landmarks. We describe the approach used to insert the catheter and the exploration of the region by ultrasound. Nerve stimulation was not used to avoid painful contractions. Analgesia was excellent during surgery and over the following 24 hours.