Ultrasound-guided Regional Block Research Articles

A sequential four-step method facilitates identifying a target nerve or site in ultrasound-guided regional block.

A sequential four-step method facilitates identifying a target nerve or site in ultrasound-guided regional block.

Comments on- Time to Adequately Heed Acute Pain in the Emergency Department – More Regional Blocks Warranted

To the Editor, I read the recent article “Time to Adequately Heed Acute Pain in the Emergency Department – More Regional Blocks Warranted” by Dr. Zundert, et al. with much interest [1]. The central argument of offering adequate multimodal acute pain control to our most vulnerable patients has been the core tenant of my clinical practice and research for the last 15 years. I completely agree that If we (as the field of medicine) hope to succeed in equitable acute pain management, leveraging the skill of numerous clinicians (emergency physicians, surgeons, orthopedics, etc.) to perform single injection regional blocks will be needed [2]. Like other skills (endotracheal intubation, lumbar puncture, central venous cannulation, etc.) that have been adapted from innovators in one field and then taught to the various other specialties, ultrasound-guided regional anesthesia needs to be brought from the expert regional anesthesiologists and to the clinicians who are at the bedside caring for this cohort of patients. Working at an academic trauma center in a low resource setting, we have had to build patient-centered pain pathways that both treat acute pain as well as ensure a reduction in opioid use. With the help of our anesthesia colleague at University of California, San Francisco, we have integrated ultrasound-guided regional blocks into our clinical practice for more than 10 years in the emergency department (ED). Just as Dr. Zundert has pointed out, this collaboration between our Anesthesia and Emergency Medicine colleagues has been an amazing success, leading to timely pain control in our acutely injured patients as well as improved patient care. For hip fractures specifically, we have worked with our anesthesia and orthopedic colleagues to develop a practice standard that asks our clinicians to perform a block in under 1 hour after recognition of a hip fracture [3]. This collaborative non-siloed based practice standard between all services dealing with acutely injured patients (trauma surgery, orthopedics, anesthesia and emergency medicine) has fostered interdepartmental education, multiple research publications and most importantly improved patient care [4, 5,6, 7].

Several considerations on how to achieve perfect ophthalmic anesthesia

The reality that most of ophthalmic surgeries are conducted under retrobulbar block or topic anesthesia performed by the ophthalmic surgeons themselves may affect the balance between quality and efficiency of ophthalmic anesthesia. The authors suggest that the key principle to perform ophthalmic anesthesia is to help the patients be well prepared preoperatively. In order to achieve this goal, we should make full use of the supraglottic airway device and awake sedation, improve ultrasound-guided regional block technique, strengthen cooperation with ophthalmic surgeons, thereby meeting the comfortable anesthesia requirements of ophthalmic surgery patients and adapting for the development trend of day surgery.

Evolution of Anesthetic Techniques for Shoulder Surgery: A Narrative Review

Shoulder surgery has radically evolved within the last 70 years, from a marginal orthopedic sub-specialty to an area of great research and advancement; consequently, anesthetic techniques have undergone important development. In fact, a wide variety of anesthetic strategies have emerged, to provide anesthesia and post-operative analgesia: general anesthesia (GA), regional anesthesia (RA), or combined GA and RA. A literature review on online databases was carried out about the different anesthetic approaches for shoulder surgery and their evolution through the years, taking in consideration papers from 1929 to 2021. A comprehensive preoperative assessment of patients undergoing shoulder surgery allows to identify and modify potential risk factors and complications of general anesthesia. Moreover, the use of ultrasound-guided regional blocks could improve the effectiveness of these techniques and bring better postoperative outcomes. Anesthetic management for shoulder surgery has progressed drastically during the last century. More studies are needed to finally standardize anesthetic techniques for specific procedure.

Piloting a New Curriculum: Guided At-Home Pediatric Regional Anesthesia Education Using a Portable Ultrasound.

Ultrasound-guided regional anesthesia is the standard of care for most regional blocks in pediatric anesthesiology.Training programs must educate physicians to perform regional blocks safely and efficiently. Hands-on learning with simulation and live models is the gold standard. The coronavirus disease 2019 (COVID-19) pandemic has greatly hampered our ability to safely hold in-person workshops. We describe an at-home, guided virtual workshop using portable ultrasound to safely continue experiential trainee education.The primary objective of this pilot virtual workshop was to develop an effective experiential learning program without the need for live child models. The main goal was to give trainees hands-on experience obtaining anatomical ultrasound images necessary for regional anesthesia blocks in a guided-virtual setting and to evaluate the effectiveness of skills acquisition. This workshop included two pediatric anesthesiology fellows and a pediatric anesthesiologist.Trainees were instructed on ultrasound-guided regional block acquisition. For two weeks, trainees acquired images/movies of regional block anatomy at home using their own children. Virtual video assistance was available. Trainees then used acquired images/movies to discuss needle and local anesthetic placement with a pediatric regional anesthesiologist. Trainees completed pre- and post-workshop surveys assessing attitudes, perceived educational efficacy, and procedural skill acquisition. The faculty member also assessed trainees’ skills.The virtual workshop was successful. Trainees expressed successful active learning and increased comfort in performing regional blocks on live patients. They correctly identified relevant anatomy of acquired images/movies, as well as needle and local anesthetic placement at the time of debriefing. Faculty were pleased with trainees’ initial performance of regional blocks.Adapting an in-person workshop to an at-home guided experience is a safe, feasible, and well-received method for anesthesiology trainees to obtain experiential learning of ultrasound-guided regional anesthesia. This facilitated at-home learning experience allows for hands-on skill practice while preventing exposure of child models to the hospital setting during a pandemic.

The Effect of Brachial Plexus Regional Block on Autologous Arteriovenous Fistula and Arteriovenous Graft Outcomes: A Prospective Study

Primary arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis, due to having the best long-term primary patency rate, fewest interventions, and lowest incidence of long-term adverse events when compared with other types of vascular access. A vein diameter >3 mm is always preferred in AVF creation. The use of ultrasound-guided regional block has been increasingly utilized in hemodialysis access creation procedures. We aim to evaluate how regional anesthesia might alter the surgical decision during a vascular access procedure by switching the surgical plan from arteriovenous graft (AVG) to AVF.

Commentary on: Enhanced Recovery After Surgery Protocol With Ultrasound-Guided Regional Blocks in Outpatient Plastic Surgery Patients Leads to Decreased Opioid Prescriptions and Consumption.

Commentary on: Enhanced Recovery After Surgery Protocol With Ultrasound-Guided Regional Blocks in Outpatient Plastic Surgery Patients Leads to Decreased Opioid Prescriptions and Consumption.

Enhanced Recovery After Surgery Protocol With Ultrasound-Guided Regional Blocks in Outpatient Plastic Surgery Patients Leads to Decreased Opioid Prescriptions and Consumption.

Opioids are a mainstay of pain management. To limit the use of opioids, enhanced recovery after surgery (ERAS) protocols implement multimodal approaches to treat postoperative pain. The aim of this paper was to be the first to assess the efficacy of an ERAS protocol for plastic surgery outpatients that includes ultrasound-guided, surgeon-led regional blocks. A retrospective review of patients undergoing outpatient plastic surgery on an ERAS protocol was performed. These patients were compared to a well-matched group not on an ERAS protocol (pre-ERAS). Endpoints included the amounts of opioid, antinausea, and antispasmodic medication prescribed. ERAS patients were given a postoperative questionnaire to assess both pain levels (0-10) and opioid consumption. ERAS patients anticipated to have higher levels of pain received ultrasound-guided anesthetic blocks. There were 157 patients in the pre-ERAS group and 202 patients in the ERAS group. Patients in the pre-ERAS group were prescribed more opioid (332.3 vs 100.3 morphine milligram equivalents (MME)/patient; P < 0.001), antinausea (664 vs 16.3 mg of promethazine/patient; P < 0.001), and antispasmodic (401.3 vs 31.2 mg of cyclobenzaprine/patient; P < 0.001) medication. Patients on the ERAS protocol consumed an average total of 22.7 MME/patient postoperatively. Average pain scores in this group peaked at 5.32 on postoperative day 1 and then decreased significantly daily. Implementation of an ERAS protocol for plastic surgery outpatients with utilization of ultrasound-guided regional anesthetic blocks is feasible and efficacious. The ability to significantly decrease prescribed opioids in this unique patient population is noteworthy.

An Evaluation of Complications Following Ultrasound-Guided Regional Block Anesthesia in Outpatient Hand Surgery.

Background: Ultrasound-guided (USG) assistance has contributed to the acceptance of regional anesthesia as a safe and efficient alternative to traditional general anesthesia. However, limited data exist regarding the safety of supraclavicular blocks used in common hand surgery procedures. The purpose of this retrospective study was to evaluate a large sample of cases to determine the effectiveness and complication rate of supraclavicular nerve blocks and confirm the safety of its use within the ambulatory surgery center (ASC) setting. Methods: Nerve blocks for the upper extremity were performed via the supraclavicular approach using the USG technique. Records were analyzed for all patients monitored during the immediate postoperative recovery and step-down phases at the ASC and contacted by phone or evaluated within 2 weeks at their first postoperative visit. Adverse outcomes related to the regional block anesthesia were identified via phone interview or postoperative surgical visit and documented. Results: In all, 713 records were reviewed with 56% female (n = 398) and 44% male (n = 315) patients. Of the 713 cases, 4 adverse events were identified (0.6%, 95% confidence interval [%]), including 2 abnormal reactions to the nerve block and 2 incomplete blocks with inadequate pain control. Conclusions: This study is the first report to evaluate a large sample of outpatient hand procedures at a high-volume ASC. We can report no clinically significant pulmonary or neurovascular complications with the use of USG supraclavicular nerve block techniques, further supporting its establishment as a safe and efficient procedure, yielding a low complication rate.

Color Doppler Ultrasound-guided Axillary Brachial Plexus Block in Patient without Brachial Pulse: A Case Report

Color Doppler ultrasound-guided regional block like brachial plexus block lately changed other anesthesia and analgesia practice because of the accuracy and simplicity of practice to view the anatomy of blood vessels and nerves. With color Doppler ultrasound-guided regional block you can follow needle track to nerves and prevent any vessel puncture. It can be the standard for any regional block. The patient was a 64 years Iranian who had diabetes mellitus and hypertension and planned as an urgent right upper limb amputation surgery. Because of the acute exacerbation of COPD due to pneumonia we decided to use regional anesthesia for this patient. On the first physical examination there was no peripheral pulse in patient’s right hand. With ultra-sonographic color Doppler the pulselessness of right hand artery were monitored. With the anatomic and awareness of grey-scaled ultrasonography the nerves and vessels were found. Axillary brachial plexus block with guidance of grey-scaled ultrasonography were done and the surgery was successfully performed and patient transferred to ICU for post operation care after surgery.

Do ultrasound-guided regional blocks signify a new paradigm in high-risk patients?

It has been suggested for many years that regional anaesthesia is advantageous in high-risk patients, either as the sole anaesthetic or in combination with general anaesthesia. Regional techniques are safe and even more so when guided by ultrasound. In the high-risk patient population, ultrasound-guided regional anaesthesia (UGRA) can help decrease risk of perioperative morbidity and improve short-term as well as long-term outcomes, particularly in the orthopaedic, vascular, oncologic and chronic pain patient populations. Nevertheless, complications do still occur and benefits of a specific regional nerve blockade need to be weighed against potential risks on an individual basis. The emergence of reasonably priced, easy-to-use ultrasound machines facilitates regional anaesthesia, and this kind of anaesthesia may become the standard of care in high-risk patients.

Emergency Transfemoral Amputation in a Severely Sick and Hemodynamically Unstable Patient through Eco-Guided Peripheral Nerve Block: Case Report

Critically ill and/or anticoagulated patients remain a great challenge for anesthesiologists regarding the anesthetic procedure. Its perioperative management should focus on organ preservation and avoid further damage. In this context, ultrasound-guided regional blocks are essential tools, as they avoid neuraxial invasion and deterioration in borderline hemodynamics, conferred by spinal anesthesia and general anesthesia, respectively. In this report, we present a case of a patient with septic shock, anticoagulated, and in need of an emergency surgical approach in the right lower limb in which ultrasound-guided peripheral nerve block was essential for a favorable outcome for the patient. Case Report: Patient in septic shock in need of amputation of the right lower limb at the level of the thigh, with unstable hemodynamics and severe respiratory conditions, undergoing ultrasound-guided peripheral nerve block, of the right femoral, sciatic and lateral cutaneous nerves of the thigh, as a single anesthetic technique. Conclusion: Regional anesthesia of the peripheral nerve guided by ultrasound as a unique anesthetic technique, performed by experienced professionals or under supervision, is effective and safe for lower limb surgical procedures. We suggest this approach, especially in hemodynamically borderline patients or seriously ill with or without anticoagulation.

Four kidneys and a tumor: Laparoscopic radical nephrectomy in a renal transplant recipient

Ever since the advent of organ transplantation, the survival rate and future encounter of recipients with anesthesiologists has increased. There have been several case reports and reviews on anesthesia for renal transplant recipients. We present a unique case of a patient who had previously undergone double renal transplantation, presenting to the anesthesiologist with four kidneys for laparoscopic radical nephrectomy for renal cell carcinoma. To the best of our knowledge, there has been no reported case of a postrenal transplant patient with four kidneys presenting for minimally invasive radical nephrectomy. Hemodynamic stability, preservation of renal function, careful choice of anesthetic agents, protection of fistula sites, complete asepsis, institution of extensive monitoring, cautious positioning, and use of ultrasound-guided regional block for pain management are some of the clinical pearls gained from this unique and rare case.

Novel Applications in Ultrasound Technology for Regional Anesthesia

Ultrasound-guided regional block (UGRA) of peripheral nerves is now common practice. Nerves, muscle, blood vessels and circumferential perineural spread of local anaesthetic are all seen in real time. However, the utility of B-Mode ultrasound may be limited when adjacent tissues have similar acoustic properties, and several diverse approaches have been taken to improve tissue contrast, particularly in cancer imaging. Examples include: 3D and 4D imaging, software modifications such as harmonics and beam steering, and clinical measurement of the fundamental properties of tissue such as stress and strain. Despite incorporation of new ultrasound technologies into cancer imaging, the practice of UGRA remains restricted to B-Mode ultrasound. Therefore, the objective of this review is to describe the principles of advanced ultrasound technologies, their application to cancer imaging, and their potential use within UGRA.

A trigonometric method to confirm needle tip position during out-of-plane ultrasound-guided regional blockade

To the Editor, A common challenge using the out-of-plane approach during ultrasound-guided regional blocks is ensuring that the hyperechoic dot visualized on the screen is the needle tip and not the cross-section of the needle shaft. For superficial targets (1-2 cm), this can often be overcome by employing the ‘‘walkdown’’ approach. This technique involves inserting the needle at incrementally steeper angles, allowing identification of the tip until it is observed adjacent to the target nerve. With this method, the needle is inserted at a final angle of 45 , and the distance between the needle and probe equals the depth of the nerve. At depths greater than 2 cm, the ‘‘walkdown’’ approach becomes impractical. Targeting any nerve deeper than 2 cm requires a long needle because the needle insertion depth increases in proportion to the target depth and insertion distance. For example, using the Pythagorean theorem (a ? b = c), where a is a target depth of 3 cm, b is an insertion distance of 3 cm, and c is the needle insertion depth required to reach the target (see Figure), we find that a 5 cm needle would be barely long enough to reach the target (c = H(3 ? 3) = 4.24). Moreover, the further distance the needle is from the transducer, the further distance the needle must traverse tissue without real-time ultrasound guidance, in effect ‘‘blinding’’ it to the structures in its trajectory. Alternatively, we can circumvent these problems by reducing the distance between the insertion site and the ultrasound beam. Ideally, the needle would be inserted perpendicularly along the ultrasound scanning plane; however, in reality, the minimum distance is about 0.5 cm due to the space occupied by the footprint of the transducer. Again, applying the principles of trigonometry, a distance B 1 cm between the needle and the ultrasound beam becomes negligible as the target depth increases, and the needle insertion depth becomes comparable with the target depth. For instance, the difference between the depth of needle insertion and the actual depth of the target is minimal when the needle is directly adjacent to the transducer with a maximum distance of 1 cm away from the ultrasound beam: Needle length required 1⁄4 p 2 cm target depth ð Þ þ 1 cm insertion distance ð Þ 1⁄4 2:2 cm

Current concepts and future trends in ultrasound-guided regional anesthesia

Ultrasound guidance for regional anesthesia has gained enormous popularity during the past several years. This review article highlights the importance of acquiring an understanding and knowledge of human anatomy for well tolerated and effective performance of regional anesthesia; includes description of some of the major principles of ultrasound-guided regional anesthesia techniques (adequate identification of neuronal and adjacent anatomical structures along with the procedure needle); use of adequate volumes of local anesthetic and the proper administration of local anesthetic; and discusses economical along with educational aspects of ultrasound-guided regional blocks. Recent studies by various authors have indicated that ultrasound-guided regional blocks can be performed by using smaller volumes of local anesthetics. Such findings will further contribute to the safety of regional anesthesia in daily clinical practice. Additional positive economical aspects associated with regional anesthesia have also been described in the recent literature. With little reservation, it is anticipated that ultrasound-guided regional anesthesia will become the 'GOLD' standard for performance of regional anesthesia. Excellent science and educational concepts will continue to be required with the continued increase in popularity of this exciting specialty of anesthesia.

Ultrasound-Guided Femoral and Sciatic Nerve Blocks in an Anticoagulated Patient. Case Reports

The use of the ultrasound to guide the puncture in peripheral nerve blocks has become increasingly more frequent. With the lower probability of promoting vascular damage the ultrasound has become an interesting tool in peripheral nerve blocks especially in patients in use of anticoagulants or with coagulopathies. The objective of this article was to report two cases in which ultrasound-guided sciatic and femoral nerve blocks were performed in anticoagulated patients. In the first case, the patient underwent amputation of the left forefoot due to necrosis and signs of infection, and in the second case, surgical cleaning of the left knee. Patients had changes in coagulation with levels of activity of prothrombin and activated partial thromboplastin time above normal limits. Both patients underwent ultrasound-guided femoral and sciatic nerve blocks, evolving without motor or sensorial changes in the territories of those nerves and without hematoma at the site of puncture. Anticoagulation imposes some restrictions to classical regional anesthetic techniques. With the development of ultrasound equipment and methods, it is now possible to accurately identify vascular and neural structures. This allows ultrasound-guided puncture to be more precise, both to achieve the area of interest and to minimize the risks of accidental vascular damage. Until now, peripheral block was not recommended in anticoagulated patients or in those with coagulopathies. However, considering that few reports on ultrasound-guided regional blocks in coagulopathies can be found in the literature, the safety of this technique in this condition has yet to be established.

Complication during Ultrasound-guided Regional Block: Accidental Intravascular Injection of Local Anesthetic

Complication during Ultrasound-guided Regional Block: Accidental Intravascular Injection of Local Anesthetic

Ultrasound-guided Peripheral Nerve Blocks and Intravascular Injection

Clement Zablocki VA Medical Center and Medical College of Wisconsin, Milwaukee, Wisconsin. hshankar@mcw.eduTo the Editor: —In the April issue of Anesthesiology, Loubert et al. 1and Zetlaoui et al. 2reported about possible intravascular injection after an ultrasound-guided axillary block. Their reports highlight the need for vigilance in the performance of ultrasound-guided blocks. This and similar reports of complications3–5after ultrasound-guided regional blocks reinforce the need for proper training, and the understanding that ultrasound, after all, is only a tool. Any tool should be used with full cognizance of its limitations. The major limitations of ultrasound-guided blocks are technical,6including the angle of incidence, needle visualization, and possibly artifacts.7,8Training in the proper holding of the probe while analyzing and while injecting help overcome some of the complications. Sometimes even with proper training, complications do occur.4The reports1,2have similarities and differences besides the ultrasound-guided axillary block and intravascular complication leading to seizure. One of them described the changes in vital signs,1and the other reports some technical difficulties in getting the data.2Needle visualization was an issue in both reports. Using an out-of-plane approach may have prevented proper needle visualization because only a cross section of the needle anywhere in the length of the needle may be seen and mistaken for the tip, although tissue movement may have been seen. With the in-plane approach used in the other report, needle artifacts may have prevented proper visualization, which will only be discerned when the injectate spread is noticed. Both reports mention distortion of tissues, one due to probe pressure and the other due to local anesthetic already injected.There is no documentation in either of the reports of having seen other vessels in the proximity before the actual needle placement. Assuming they used color flow Doppler, the default settings for the color Doppler cannot detect small vessels unless the color velocity range and the angle of steering are adjusted. It is possible that they did not visualize the needle during the performance of the block and hence did not adhere to one of the safety principles that they have mentioned. Any of these situations could have led to the complication. Most importantly, they were both performed by residents.My practice is to perform a preliminary scout scan, including a color flow study, to visualize the target and its associated neighboring structures and demonstrate to the trainee. This permits proper guidance during the actual performance of the block. Could they have avoided the intravascular injection by using landmarks or nerve stimulation? Probably not.To elevate ultrasound-guided to the next level and call it a “bulletproof technique” by the more “vocal proponents”6is a dream awaiting fruition with some more technological advancements and changes in needle design. In the meantime, adhering to some basic principles will avoid potential complications. To blame the ultrasound for complications due to technical and possibly inadequate training is, in my opinion, tarnishing a useful technique without understanding its advantages and mainly its limitations. There is an increasing need for a proper curriculum and training to fully understand the technique, the potential pitfalls, and the complications of ultrasound-guided blocks.9Clement Zablocki VA Medical Center and Medical College of Wisconsin, Milwaukee, Wisconsin. hshankar@mcw.edu

Complication during Ultrasound-guided Regional Block: Accidental Intravascular Injection of Local Anesthetic

Complication during Ultrasound-guided Regional Block: Accidental Intravascular Injection of Local Anesthetic