Glucagon-Like Peptide-1 Receptor Agonist Use and Residual Gastric Content Before Anesthesia

Importance

Glucagon-like peptide-1 receptor agonist (GLP-1 RA) use is rapidly increasing in the US, driven by its expanded approval for weight management in addition to hyperglycemia management in patients with type 2 diabetes. The perioperative safety of these medications, particularly with aspiration risk under anesthesia, is uncertain.

Objective

To assess the association between GLP-1 RA use and prevalence of increased residual gastric content (RGC), a major risk factor for aspiration under anesthesia, using gastric ultrasonography.

Design, Setting, and Participants

This cross-sectional study prospectively enrolled patients from a large, tertiary, university-affiliated hospital from June 6 through July 12, 2023. Participants followed preprocedural fasting guidelines before an elective procedure under anesthesia. Patients with altered gastric anatomy (eg, from previous gastric surgery), pregnancy, recent trauma (<1 month), or an inability to lie in the right lateral decubitus position for gastric ultrasonography were excluded.

Exposure

Use of a once-weekly GLP-1 RA.

Main Outcomes and Measures

The primary outcome was the presence of increased RGC, defined by the presence of solids, thick liquids, or more than 1.5 mL/kg of clear liquids on gastric ultrasonography. Analysis was adjusted for confounders using augmented inverse probability of treatment weighting, a propensity score-based technique. Secondarily, the association between the duration of drug interruption and the prevalence of increased RGC was explored.

Results

Among the 124 participants (median age, 56 years [IQR, 46-65 years]; 75 [60%] female), the prevalence of increased RGC was 56% (35 of 62) in patients with GLP-1 RA use (exposure group) compared with 19% (12 of 62) in patients who were not taking a GLP-1 RA drug (control group). After adjustment for confounding, GLP-1 RA use was associated with a 30.5% (95% CI, 9.9%-51.2%) higher prevalence of increased RGC (adjusted prevalence ratio, 2.48; 95% CI, 1.23-4.97). There was no association between the duration of GLP-1 RA interruption and the prevalence of increased RGC (adjusted odds ratio, 0.86; 95% CI, 0.65-1.14).

Conclusions and Relevance

Use of a GLP-1 RA was independently associated with increased RGC on preprocedural gastric ultrasonography. The findings suggest that the preprocedural fasting duration suggested by current guidelines may be inadequate in this group of patients at increased risk of aspiration under anesthesia.

Standardizing nomenclature in regional anesthesia: an ASRA-ESRA Delphi consensus study of upper and lower limb nerve blocks

BACKGROUND

Inconsistent nomenclature and anatomical descriptions of regional anesthetic techniques hinder scientific communication and engender confusion; this in turn has implications for research, education and clinical implementation of regional anesthesia. Having produced standardized nomenclature for abdominal wall, paraspinal and chest wall regional anesthetic techniques, we aimed to similarly do so for upper and lower limb peripheral nerve blocks.

METHODS

We performed a three-round Delphi international consensus study to generate standardized names and anatomical descriptions of upper and lower limb regional anesthetic techniques. A long list of names and anatomical description of blocks of upper and lower extremities was produced by the members of the steering committee. Subsequently, two rounds of anonymized voting and commenting were followed by a third virtual round table to secure consensus for items that remained outstanding after the first and second rounds. As with previous methodology, strong consensus was defined as ≥75% agreement and weak consensus as 50%-74% agreement.

RESULTS

A total of 94, 91 and 65 collaborators participated in the first, second and third rounds, respectively. We achieved strong consensus for 38 names and 33 anatomical descriptions, and weak consensus for five anatomical descriptions. We agreed on a template for naming peripheral nerve blocks based on the name of the nerve and the anatomical location of the blockade and identified several areas for future research.

CONCLUSIONS

We achieved consensus on nomenclature and anatomical descriptions of regional anesthetic techniques for upper and lower limb nerve blocks, and recommend using this framework in clinical and academic practice. This should improve research, teaching and learning of regional anesthesia to eventually improve patient care.

Characterizing the interplay of treatment parameters and complexity and their impact on performance on an IROC IMRT phantom using machine learning

AIM OF THE STUDY

To elucidate the important factors and their interplay that drive performance on IMRT phantoms from the Imaging and Radiation Oncology Core (IROC).

METHODS

IROC's IMRT head and neck phantom contains two targets and an organ at risk. Point and 2D dose are measured by TLDs and film, respectively. 1,542 irradiations between 2012-2020 were retrospectively analyzed based on output parameters, complexity metrics, and treatment parameters. Univariate analysis compared parameters based on pass/fail, and random forest modeling was used to predict output parameters and determine the underlying importance of the variables.

RESULTS

The average phantom pass rate was 92% and has not significantly improved over time. The step-and-shoot irradiation technique had significantly lower pass rates that significantly affected other treatment parameters' pass rates. The complexity of plans has significantly increased with time, and all aperture-based complexity metrics (except MCS) were associated with the probability of failure. Random forest-based prediction of failure had an accuracy of 98% on held-out test data not used in model training. While complexity metrics were the most important contributors, the specific metric depended on the set of treatment parameters used during the irradiation.

CONCLUSION

With the prevalence of errors in radiotherapy, understanding which parameters affect treatment delivery is vital to improve patient treatment. Complexity metrics were strongly predictive of irradiation failure; however, they are dependent on the specific treatment parameters. In addition, the use of one complexity metric is insufficient to monitor all aspects of the treatment plan.

Assistive artificial intelligence for ultrasound image interpretation in regional anaesthesia: an external validation study

BACKGROUND

Ultrasonound is used to identify anatomical structures during regional anaesthesia and to guide needle insertion and injection of local anaesthetic. ScanNav Anatomy Peripheral Nerve Block (Intelligent Ultrasound, Cardiff, UK) is an artificial intelligence-based device that produces a colour overlay on real-time B-mode ultrasound to highlight anatomical structures of interest. We evaluated the accuracy of the artificial-intelligence colour overlay and its perceived influence on risk of adverse events or block failure.

METHODS

Ultrasound-guided regional anaesthesia experts acquired 720 videos from 40 volunteers (across nine anatomical regions) without using the device. The artificial-intelligence colour overlay was subsequently applied. Three more experts independently reviewed each video (with the original unmodified video) to assess accuracy of the colour overlay in relation to key anatomical structures (true positive/negative and false positive/negative) and the potential for highlighting to modify perceived risk of adverse events (needle trauma to nerves, arteries, pleura, and peritoneum) or block failure.

RESULTS

The artificial-intelligence models identified the structure of interest in 93.5% of cases (1519/1624), with a false-negative rate of 3.0% (48/1624) and a false-positive rate of 3.5% (57/1624). Highlighting was judged to reduce the risk of unwanted needle trauma to nerves, arteries, pleura, and peritoneum in 62.9-86.4% of cases (302/480 to 345/400), and to increase the risk in 0.0-1.7% (0/160 to 8/480). Risk of block failure was reported to be reduced in 81.3% of scans (585/720) and to be increased in 1.8% (13/720).

CONCLUSIONS

Artificial intelligence-based devices can potentially aid image acquisition and interpretation in ultrasound-guided regional anaesthesia. Further studies are necessary to demonstrate their effectiveness in supporting training and clinical practice.

CLINICAL TRIAL REGISTRATION

NCT04906018.

Ultrasound-guided percutaneous cryoneurolysis for management of acute sternal fracture pain

Background

Establishing adequate analgesia for rib and sternal fractures remains a challenge due to the prolonged nature of the associated pain. Historically, cryoneurolysis has demonstrated beneficial in treating chronic pain, and the recent development of hand-held devices has allowed its functionality to expand into the management of acute pain.

Case

We present a polytrauma patient with sternal and multiple rib fractures that underwent ultrasound-guided intercostal cryoneurolysis at bedside, resulting in significant analgesia lasting several weeks and improving mobilization. This is the first report of the utilization of cryoneurolysis to treat acute sternal fracture pain.

Conclusion

The most common sternal fracture pattern is transverse which only requires treatment of four intercostal nerves, making cryoneurolysis feasible in trauma centers. This portable, minimally invasive, and low risk technique has the added benefits of reducing opioid requirements, decreasing length of hospital stay, and improving mobility in polytrauma patients.

Ultrasound-Guided Percutaneous Intercostal Cryoneurolysis for Acute-on-Chronic Pain in CLOVES Syndrome

Cryoneurolysis is an analgesic method that has been shown to provide extended pain relief in postoperative patients. However, to date, this method has not been described in nonsurgical inpatients with chronic pain experiencing an acute exacerbation. This analgesic modality has the potential to provide pain relief for patients whose expected duration of severe acute pain would outlast that of other regional anesthetic techniques while avoiding opioid escalation and facilitating discharge. We present a patient with acute exacerbation of chronic pain from breast ulcerations caused by congenital lipomatous overgrowth, vascular malformations, epidermal nevis, spinal/skeletal anomalies/scoliosis (CLOVES) syndrome that was successfully treated as an inpatient with a portable cryoneurolysis device.  This is the first reported use of cryoneurolysis in an inpatient setting to treat acute-on-chronic pain in a nonsurgical patient. The authors recommend regional anesthesiologists and acute pain specialists to utilize this technique to provide analgesia in patients with complex pain to facilitate hospital throughput.

Chronic Pain: An Update of Clinical Practices and Advances in Chronic Pain Management

Chronic pain affects a significant amount of the population and represents a heavy personal and socioeconomic burden. Chronic pain mechanisms can be categorized as nociceptive, neuropathic, or nociplastic. Although mechanism-based pain treatment is optimal, different types of pain mechanisms may overlap in patients. Recently, the biopsychosocial model with the multidisciplinary pain management program is widely accepted as one of the most effective methods to assess and manage chronic pain. The treatment of chronic pain consists of a personalized, stepwise, and multimodal approach that includes pharmacotherapy, psychotherapy, integrative treatments, and interventional procedures. Somatic and peripheral nerve blocks for the treatment of chronic pain are often deferred. With the increasing use of ultrasound in pain medicine, newly defined interfascial plane blocks, which may be performed alone or as an adjuvant to multimodal management, have gained popularity. Adequate pain management can improve physical functioning, mental health and quality of life indicators, and reduce pain chronification. The aim of this current article is to perform a comprehensive and updated review of existing treatment options, particularly interfascial plane blocks in chronic pain syndromes.

The current status and shortcomings of stereotactic radiosurgery

Background

Stereotactic radiosurgery (SRS) is a common treatment for intracranial lesions. This work explores the state of SRS treatment delivery to characterize current treatment accuracy based on treatment parameters.

Methods

NCI clinical trials involving SRS rely on an end-to-end treatment delivery on a patient surrogate (credentialing phantom) from the Imaging and Radiation Oncology Core (IROC) to test their treatment accuracy. The results of 1072 SRS phantom irradiations between 2012 and 2020 were retrospectively analyzed. Univariate analysis and random forest models were used to associate irradiation conditions with phantom performance. The following categories were evaluated in terms of how they predicted outcomes: year of irradiation, TPS algorithm, machine model, energy, and delivered field size.

Results

Overall, only 84.6% of irradiations have met the IROC/NCI acceptability criteria. Pass rate has remained constant over time, while dose calculation accuracy has slightly improved. Dose calculation algorithm (P < .001), collimator (P = .024), and field size (P < .001) were statistically significant predictors of pass/fail. Specifically, pencil beam algorithms and cone collimators were more likely to be associated with failing phantom results. Random forest modeling identified the size of the field as the most important factor for passing or failing followed by algorithm.

Conclusion

Constant throughout this retrospective study, approximately 15% of institutions fail to meet IROC/NCI standards for SRS treatment. In current clinical practice, this is particularly associated with smaller fields that yielded less accurate results. There is ongoing need to improve small field dosimetry, beam modeling, and QA to ensure high treatment quality, patient safety, and optimal clinical trials.

Recommendations for effective documentation in regional anesthesia: an expert panel Delphi consensus project

Background and objectives

Documentation is important for quality improvement, education, and research. There is currently a lack of recommendations regarding key aspects of documentation in regional anesthesia. The aim of this study was to establish recommendations for documentation in regional anesthesia.

Methods

Following the formation of the executive committee and a directed literature review, a long list of potential documentation components was created. A modified Delphi process was then employed to achieve consensus amongst a group of international experts in regional anesthesia. This consisted of 2 rounds of anonymous electronic voting and a final virtual round table discussion with live polling on items not yet excluded or accepted from previous rounds. Progression or exclusion of potential components through the rounds was based on the achievement of strong consensus. Strong consensus was defined as ≥75% agreement and weak consensus as 50%–74% agreement.

Results

Seventy-seven collaborators participated in both rounds 1 and 2, while 50 collaborators took part in round 3. In total, experts voted on 83 items and achieved a strong consensus on 51 items, weak consensus on 3 and rejected 29.

Conclusion

By means of a modified Delphi process, we have established expert consensus on documentation in regional anesthesia.

The Use of Peripheral Nerve Blockade in Laparoscopic and Robotic Surgery: Is There a Benefit?

PURPOSE OF REVIEW

The purpose of this review is to synthesize recent literature investigating the use of regional anesthesia for minimally invasive surgery.

RECENT FINDINGS

Recent studies investigating the use of newer peripheral nerve blocks such as erector spinae plane (ESP) and quadratus lumborum (QL) block are very limited. Evidence supporting the use of peripheral nerve blockade in laparoscopic or robotic surgery is very limited and of low-moderate quality. While transverse abdominal plane (TAP) block may decrease opioid and pain scores after laparoscopic cholecystectomy, bariatric surgery, and colorectal surgery, the benefit of the block in the presence of multimodal analgesia remains to be clarified. Unilateral paravertebral block may be beneficial for percutaneous nephrolithotomy. ESP and rectus sheath blockade may enhance analgesia in laparoscopic surgery, but the magnitude of this benefit may not be clinically relevant. Limited evidence supports the use of QL block in laparoscopic urologic surgery. There is insufficient recent evidence to support the use of TAP or QL block for laparoscopic gynecologic surgery.

Interscalene Block for Analgesia in Orthopedic Treatment of Shoulder Trauma: Single-Dose Liposomal Bupivacaine versus Perineural Catheter

Background

Interscalene brachial plexus block is frequently utilized to provide perioperative analgesia to patients undergoing shoulder surgery to optimize recovery, minimize opioid consumption, and decrease overall hospital length of stay. The use of an indwelling perineural interscalene catheter provides extended analgesia and is efficacious in managing severe postoperative pain following major shoulder surgery. Currently, the only alternative to perineural catheters for extended analgesia with interscalene block involves the perineural infiltration of liposomal bupivacaine. However, there is limited published data regarding the overall analgesic effectiveness of using interscalene liposomal bupivacaine in the setting of shoulder surgery.

Methods

We performed a retrospective review of 43 patients in the acute trauma setting who underwent major shoulder surgery and received extended analgesia via perioperative interscalene brachial plexus block with either an indwelling continuous catheter or single-dose liposomal bupivacaine to determine if comparable analgesia can be achieved. The primary outcomes of interest were postoperative pain scores and opioid consumption. Due to the ability to titrate and bolus local anesthetic infusions to a desired clinical effect, we hypothesized that opioid consumption and pain scores would be lower when using the continuous catheter technique.

Results

After statistical analysis, our results demonstrated no significant difference between the two techniques in regards to opioid consumption as well as numeric pain scores during the 48-hour postoperative period, but did note a higher rate of complications with patients who received perineural interscalene continuous catheters. Secondary outcomes showed an increase in time required to complete the regional block procedure with the use of indwelling catheters.

Conclusion

Interscalene brachial plexus block with liposomal bupivacaine may be a viable alternative to indwelling continuous catheters for providing extended analgesia in patients undergoing major shoulder surgery.

Standardizing nomenclature in regional anesthesia: an ASRA-ESRA Delphi consensus study of abdominal wall, paraspinal, and chest wall blocks

BACKGROUND

There is heterogeneity in the names and anatomical descriptions of regional anesthetic techniques. This may have adverse consequences on education, research, and implementation into clinical practice. We aimed to produce standardized nomenclature for abdominal wall, paraspinal, and chest wall regional anesthetic techniques.

METHODS

We conducted an international consensus study involving experts using a three-round Delphi method to produce a list of names and corresponding descriptions of anatomical targets. After long-list formulation by a Steering Committee, the first and second rounds involved anonymous electronic voting and commenting, with the third round involving a virtual round table discussion aiming to achieve consensus on items that had yet to achieve it. Novel names were presented where required for anatomical clarity and harmonization. Strong consensus was defined as ≥75% agreement and weak consensus as 50% to 74% agreement.

RESULTS

Sixty expert Collaborators participated in this study. After three rounds and clarification, harmonization, and introduction of novel nomenclature, strong consensus was achieved for the names of 16 block names and weak consensus for four names. For anatomical descriptions, strong consensus was achieved for 19 blocks and weak consensus was achieved for one approach. Several areas requiring further research were identified.

CONCLUSIONS

Harmonization and standardization of nomenclature may improve education, research, and ultimately patient care. We present the first international consensus on nomenclature and anatomical descriptions of blocks of the abdominal wall, chest wall, and paraspinal blocks. We recommend using the consensus results in academic and clinical practice.

American Society of Regional Anesthesia and Pain Medicine expert panel recommendations on point-of-care ultrasound education and training for regional anesthesiologists and pain physicians-part II: recommendations

Point-of-care ultrasound (POCUS) is a critical skill for all regional anesthesiologists and pain physicians to help diagnose relevant complications related to routine practice and guide perioperative management. In an effort to inform the regional anesthesia and pain community as well as address a need for structured education and training, the American Society of Regional Anesthesia and Pain Medicine Society (ASRA) commissioned this narrative review to provide recommendations for POCUS. The recommendations were written by content and educational experts and were approved by the guidelines committee and the Board of Directors of the ASRA. In part II of this two-part series, learning goals and objectives were identified and outlined for achieving competency in the use of POCUS, specifically, airway ultrasound, lung ultrasound, gastric ultrasound, the focus assessment with sonography for trauma exam, and focused cardiac ultrasound, in the perioperative and chronic pain setting. It also discusses barriers to POCUS education and training and proposes a list of educational resources. For each POCUS section, learning goals and specific skills were presented in the Indication, Acquisition, Interpretation, and Medical decision-making framework.

American Society of Regional Anesthesia and Pain Medicine expert panel recommendations on point-of-care ultrasound education and training for regional anesthesiologists and pain physicians-part I: clinical indications

Point-of-care ultrasound (POCUS) is a critical skill for all regional anesthesiologists and pain physicians to help diagnose relevant complications related to routine practice and guide perioperative management. In an effort to inform the regional anesthesia and pain community as well as address a need for structured education and training, the American Society of Regional Anesthesia and Pain Medicine (ASRA) commissioned this narrative review to provide recommendations for POCUS. The guidelines were written by content and educational experts and approved by the Guidelines Committee and the Board of Directors of the ASRA. In part I of this two-part series, clinical indications for POCUS in the perioperative and chronic pain setting are described. The clinical review addresses airway ultrasound, lung ultrasound, gastric ultrasound, the focus assessment with sonography for trauma examination and focused cardiac ultrasound for the regional anesthesiologist and pain physician. It also provides foundational knowledge regarding ultrasound physics, discusses the impact of handheld devices and finally, offers insight into the role of POCUS in the pediatric population.

Lumbosacral paraspinal interfascial plane blocks for pain control after feminizing genital gender affirmation surgery

Aim: Feminizing genital gender affirmation surgery (fgGAS) is increasing in prevalence in the USA. Management of postoperative pain following fgGAS is challenging. We report a series of patients where post-fgGAS pain was adequately controlled with paraspinal blocks. Materials & methods: This is a case series of three patients who received bilateral lumbar and sacral erector spinae plane blocks after fgGAS. Block techniques, medications administered, opioid requirements and pain scores were reviewed. Results: Erector spinae plane blocks provided adequate analgesia for 24-48 h following the block. Conclusion: Currently, there are two regional anesthetic techniques described for the treatment of postoperative pain after fgGAS. We describe two additional approaches as options for improved pain management in this patient population.

Scoping Review of Healthcare Literature on Mobile, Wearable, and Textile Sensing Technology for Continuous Monitoring

Remote monitoring of health can reduce frequent hospitalisations, diminishing the burden on the healthcare system and cost to the community. Patient monitoring helps identify symptoms associated with diseases or disease-driven disorders, which makes it an essential element of medical diagnoses, clinical interventions, and rehabilitation treatments for severe medical conditions. This monitoring can be expensive and time-consuming and provide an incomplete picture of the state of the patient. In the last decade, there has been a significant increase in the adoption of mobile and wearable devices, along with the introduction of smart textile solutions that offer the possibility of continuous monitoring. These alternatives fuel a technology shift in healthcare, one that involves the continuous tracking and monitoring of individuals. This scoping review examines how mobile, wearable, and textile sensing technology have been permeating healthcare by offering alternate solutions to challenging issues, such as personalised prescriptions or home-based secondary prevention. To do so, we have selected 222 healthcare literature articles published from 2007 to 2019 and reviewed them following the PRISMA process under the schema of a scoping review framework. Overall, our findings show a recent increase in research on mobile sensing technology to address patient monitoring, reflected by 128 articles published in journals and 19 articles in conference proceedings between 2014 and 2019, which represents 57.65% and 8.55% respectively of all included articles.

Posterior Quadratus Lumborum Block for Labor Analgesia: A Case Report

Neuraxial analgesia has been established as the standard of care for labor analgesia. However, patients presenting with coagulopathy require anesthesiologists to explore alternate analgesic techniques. Systemic opioids may result in neonatal respiratory depression, and inhaled nitrous oxide may lead to nausea, vomiting, and over sedation and may not be readily available in all labor and delivery units. In this case report, we describe a case where posterior quadratus lumborum blocks provided effective analgesia in a parturient with Hemophilia A during the first stage of labor.

Relief of Secondary Headaches with High Thoracic Erector Spinae Plane Block

Intractable headaches can be debilitating, often leading to significant distress, prolonged medical treatment, and unanticipated hospital admissions. There have been significant advances in the treatment of primary intractable headaches such as migraines, tension headaches, and cluster headaches beyond medical management. Treatments may now include interventional strategies such as trigger-point injections, peripheral nerve stimulators, or peripheral nerve and ganglion blocks. There are few studies, however, describing the use of interventional techniques for the management of intractable secondary headaches, including those attributed to injury or infection. A new regional anesthetic technique, the erector spinae plane (ESP) block, was initially used for neuropathic thoracic pain. ESP block has since been reported to provide acute and chronic pain relief of the shoulder, spine, abdomen, pelvis, thorax, and lower extremity. Additionally, there has been one case report to describe the use of the ESP block in the treatment of refractory tension headache. We report four cases of effective analgesia for intractable secondary headache resistant to medical management with high thoracic ESP blocks. In each case, the ESP block provided instant pain relief. We suggest that the findings of this case series indicate that the ESP block may be a useful intervention in patients with severe secondary headache or posterior cervical pain where conventional therapies have limited success, though more studies are necessary.

Upper extremity regional anesthesia techniques: A comprehensive review for clinical anesthesiologists

Surgeries and chronic pain states of the upper extremity are quite common and pose unique challenges for the clinical anesthesiology and pain specialists. Most innervation of the upper extremity involves the brachial plexus. The four most common brachial plexus blocks performed in clinical setting include the interscalene, supraclavicular, infraclavicular, and axillary brachial plexus blocks. These blocks are most commonly performed with the use of ultrasound-guided techniques, whereby analgesia is achieved by anesthetizing the brachial plexus at different levels such as the roots, divisions, cords, and branches. Additional regional anesthetic techniques for upper extremity surgery include wrist, intercostobrachial, and digital nerve blocks, which are most frequently performed using landmark anatomical techniques. This review provides a comprehensive summary of each of these blocks including anatomy, best practice techniques, and potential complications.

Axillary Impella insertion under regional nerve block: A case report

Percutaneous coronary interventions with the Impella (Abiomed, MA) catheter-based, micro-axial mechanical left ventricular assist device is a safe option for patients undergoing higher risk interventions. However, severe peripheral arterial disease limits vascular access for Impella insertion. Upper extremity arterial access has been traditionally obtained under general anesthesia. We present the first case, to our knowledge, of using peripheral nerve blocks for Impella 3.5 CP insertion into the axillary artery.

Opioid-Free Cesarean Section with Bilateral Quadratus Lumborum Catheters

Introduction

Post-operative pain control following cesarean section delivery (CD) is an important topic of discussion given the lack of consensus on a narcotic-sparing analgesic regimen. We describe the case of an elective CD with narcotic-free pain control using continuous bilateral posterior quadratus lumborum (QL) blockade as the primary mode of analgesia.

Case Report

The patient is a 36-year-old female, G3P1, who presented at 37 weeks of gestation in active labor scheduled for elective primary CD. A spinal anesthetic was performed at L4-L5 with hyperbaric 0.75% bupivacaine, without intrathecal morphine. Bilateral posterior QL catheters were placed under sterile conditions with 20 mL of 0.25% bupivacaine per side. Continuous infusion of 0.2% ropivacaine was then started at 10 mL/hour per side. The patient's pain was controlled with QL catheters and a multimodal pain regimen consisting of non-steroidal anti-inflammatory drugs and acetaminophen. The patient reported a resting pain score of 0 with a dynamic pain score of 3 out of 10 throughout her recovery. She was discharged on post-operative (post-op) day 3 and the catheters were removed without any complications.

Discussion

The gold standard for pain control following CD is intrathecal morphine; however, its use has many adverse effects. Bilateral single-shot QL blocks following CD have been proven to decrease opioid consumption but its limited duration has minimal advantage over intrathecal morphine and patients continue to require oral narcotics for analgesia. With the use of QL catheters and a multimodal pain regimen, it may be possible to achieve opioid-free CD for the post-op period.

P334 Heart model method: could it be a new echocardiographic gold-standard for the assessment of the left ventricular systolic function in a population under chemotherapy treatment?

Background

Echocardiographic assessment of the left ventricular systolic function is essential in diagnosis and during the follow up of cardiovascular diseases. Although subjective visual approach method is easily applied, quantitative systems give more objective information about systolic function analyses. The purpose of this study is to evaluate the different quantitative methods of estimating systolic function basal in non-invasive techniques

Methods

We used a group of 40 patients, prospectively collected, under chemotherapy treatment with preserved systolic function. Same echocardiography device (Philips EPIQ-7) has been used in all studies (acquiring apical 4 and 2 chambers and 3 D of apical volume by an experimented operator). We compare three standard methods with impact in the literature (Speckle tracking and 3D Heartmodel system) to the echocardiographic gold-standard (Simpson’s biplane method). The Bland-Altman method has been used for the graphic comparison of the values of the resulting measures while the statistical comparison was made by a T-student method.

Results

Three quantitative methods were used to compare left ventricular systolic function assessment (Heart Model 3D (60.4% ± 5.2%), Strain (60.50% ± 7.1%), global longitudinal strain (-19.7 ± 3.15%) to Simpson’s biplane (mean 62.10% ± 5.75%). Values of differential means (2.73 with Heart model 3D and 2.08 with Strain) compared to Simpson’s biplane were translated to a Bland-Altman plot and means were compared with a T-student method. A statistically significant difference was found in case of the Heartmodel method compared with Simpson’s biplane (p &lt; 0.05), though it does not imply any clinical difference. Less time consuming and better segmentation of the cardiac cavities in just one beat with the 3D-Heart Model technique was a magnificent point compared to the Strain method that needed a postprocessing modification

Conclusions

Heartmodel method is probably the most time-saving and with a good accuracy of left ventricular systolic function assesment and it is not inferior compared to the echocardiographic gold-standard Simpson’s biplane method.

Abstract P334 Figure 1. Bland-Altman analysis

P923 Ultrasound follow-up of left atrial appendage occlusion devices

Background

Left atrial appendage (LAA) occlusion devices represent an important alternative to anticoagulation in patients with atrial fibrillation (AF) with high risk of bleeding and who have suffered any hemorrhagic event. At first, a transesophageal ultrasound is performed to examine cardiac cavities, take measures of LAA and discharge the presence of thrombi. We redo a new transesophageal ultrasound as a control three months later after having installed the device. The purpose of this article is to show our experience in ultrasound follow up of LAA occlusion.

Methodology

All measures of LAA were taken with the transoesophageal ultrasound device by the same operator. According to the size acquired from the appendage of each patient, they were divided into a first group with the implementation of the Watchman device (23 patients) and Amplatzer (6 patients). A transthoracic echocardiography control was performed on each patient to rule out the presence of complications after the intervention, before to be discharged from hospital. After three months, a new transoesophageal study was repeated to assess the correct position of the device and to rule out the presence of any disfunctions or clot formation.

Results

A total of 29 patients with AF (CHADSVASC 4.09 HASBLED 2.96) with a high risk of bleeding and after having suffered any complications (41% brain bleeding, 31% major gastrointestinal bleeding, 27% advanced chronic kidney disease) were presented for the implantation of a LAA closure device. Firstly, LAA size was confirm and the presence of a thrombi was rule out. No patient suffered complications during the procedure that was confirmed with transthoracic echocardiography (discharging the presence of perforation, pericardial effusion or tamponade). At three months later, we performed a new transoesophageal as a control for the assessment of the place and presence of GAPs, if any (80% correct-placed, 15% placed with a gap of 2-4 mm with passage of flow throughout). In a 10-month follow-up, it was found that practically 93% of patients were still without anticoagulation, except two patients, one of them (CHADSVASC 4 HASBLED 2) had to reintroduce oral anticoagulation due to the fact of the clot formation on the device. The second one (CHADSVASC 4 HASBLED 2) had to reintroduce temporarily fractionated heparin due to stent thrombosis in the femoral artery. None of them presented any ischemic complications or new haemorrhagic events.

Conclusions

LAA occlusion devices are an effective and safe alternative to anticoagulation in patients with atrial fibrillation with predisposition to bleeding where ultrasound techniques play an essential role in all stages of procedure (prior to implantation of the device, during and at the follow-up).

Case Report: Treatment of Refractory Post-Surgical Neuralgia With Erector Spinae Plane Block

BACKGROUND

Peripheral nerve blocks (PNBs) are used for a wide spectrum of headache and facial pain disorders. The objective of this case report is to highlight the erector spinae plane (ESP) block, which has recently been reported to successfully treat headache.

CASE PRESENTATION

A 70-year-old man with a history of mild to moderate headaches, previously ruptured aneurysm, and right pterional craniotomy and clipping of an anterior communicating artery aneurysm presented with exacerbation of chronic post-surgical scalp pain and severe headache with nausea. Results of the physical examination were not consistent with cellulitis of the scalp, complete blood count and chemistry panel results were unremarkable, and imaging revealed an intact aneurysm clip. Given the severe unilateral throbbing pain with associated nausea, he was treated with a variety of migraine abortives and other pain medications without significant relief. ESP block was performed. He tolerated the procedure well without complications. His pain decreased to 2/10 from a baseline of 9 to 10/10 30 minutes after the procedure, and he was pain free the next day. Follow-up revealed a return of his pain 1 to 2 weeks after the procedure, which prompted follow-up with an outpatient pain management specialist.

CONCLUSION

PNBs, ESP block in our case, can be a useful modality in managing chronic neuralgiform pain for treatment-refractory patients. It can provide improvement in quality of life and spare the patient from medication side effects. In an inpatient setting, it can decrease length of stay that would otherwise be extended due to a trial of multiple medications until the pain was controlled. PNBs are used for a wide spectrum of headache and facial pain disorders. This case report highlights successful management of chronic neuralgiform pain with the ESP block, which has recently been reported to successfully treat headache. ESP block provided relief to the patient's neuralgiform pain that was refractory to multiple medications, resulting in decreased length of stay, fewer medication side effects, and improved quality of life. It also provided a window for initiation of long-term pain medications.

T4 Erector Spinae Plane Block Relieves Postdural Puncture Headache: A Case Report

Postdural puncture headache (PDPH) is a common complication of neuraxial anesthesia. The gold standard treatment for PDPH is an epidural blood patch (EBP). However, the risks of EBP, and patient willingness to undergo another attempted neuraxial procedure, can prevent patients from receiving this treatment. The erector spinae plane (ESP) block has been used in the treatment of acute postoperative and chronic pain secondary to many indications at many vertebral levels, and a prior case series describes two patients in which ESP block relieved tension headache. In our case report, we describe a novel use of the ESP block at the fourth thoracic vertebral level to relieve PDPH in a super morbidly obese patient with two prior inadvertent dural punctures.

Impact of serratus plane block on pain scores and incentive spirometry volumes after chest trauma

Background: Adequate pain control is difficult to achieve in patients with multiple rib fractures (MRF). Serratus plane block (SPB) is a novel technique for alleviating rib fracture pain. Several published case reports support this hypothesis. Purpose: The purpose of this study was to evaluate the use of SPB in MRF at our level 1 trauma center. Methods: Our hospital's Regional Anesthesia Registry was queried for all trauma patients with MRF who underwent SPB between August 2014 and January 2018. Data were compared in each patient as a matched pair for the time periods before and after undergoing SPB. Thirty-four patients with similar baseline characteristics were enrolled. Results: The median number of rib fractures was 7. Ordinal pain scores were found to be improved 4 hrs after SPB from median 7/10 to 3/10 (P<0.001). Incentive spirometry (IS) volumes recorded 4 and 24 hrs postserratus plane block showed a median increase of 150 and 175 mL from baseline, respectively (P<0.001). IS volumes recorded at 48 hrs showed a median increase of 300 mL from baseline (P<0.001). Respiratory rate decreased from a median value of 24.5 to 16 breaths/min (P<0.001). SpO₂ was improved at 24 hrs from median 96% to 99% (P<0.001). Conclusion: SPB improves pain scores and IS volumes in MRF. Because it is not limited by patient positioning or anticoagulation and has a better safety profile, it may offer a viable alternative to neuraxial techniques. Additional studies are necessary to evaluate its efficacy compared to neuraxial techniques.

Erector spinae block for postoperative analgesia following axillary hidradenitis suppurativa resection: a case report

Hidradenitis suppurativa (HS) is a chronic inflammatory disease of the terminal hair follicle of the apocrine gland-bearing skin, presenting with inflamed nodules, abscesses, and sinus tracts. Autoimmune, genetic, and infectious factors have been implicated in its pathogenesis. HS can be managed medically using topical and systemic antibiotics and with tumor necrosis factor antibody therapy in severe cases. Surgical treatment can range from local excision, deroofing or excision of sinus tracts, or wide radical excision of severe lesions. Lesions can be severely painful on their own or following surgical resection. Patients may require opioid therapy due to pain from the lesions themselves or following painful surgical resection. Erector spinae block (ESB) is a recently developed plane block used for the management of pain located in the chest wall or the abdominal wall. Ultrasound guidance is used to guide placement of the needle tip between the transverse process at the desired dermatomal level and the erector spinae muscle group. Traditional descriptions of the ESB have been at the level of the fifth transverse process to treat chest wall pain; in this case report, we describe a novel use of ESB at the level of the second transverse process to treat axillary pain after surgical debridement of axillary HS.

Street dust from a heavily-populated and industrialized city: Evaluation of spatial distribution, origins, pollution, ecological risks and human health repercussions

Emissions from vehicles include particles from tire and brake wearing that can settle down and join industrial discharges into street dust. Metals present in street dust may create ecological and health threats and their analysis is of great environmental relevance. The city of Monterrey, Mexico is an industrial pillar of the country and shows an increasing fleet during the last years, which has yielded higher traffic and emissions. This study analyzes 44 street dust samples taken across the city for total element concentrations by using X-ray fluorescence. Associations and indicators are calculated to define possible origins, levels of pollution, natural or anthropogenic sources, and ecological and human health risks. High concentrations of As, Ba, Cu, Fe, Mo, Ni, Pb, Ti, and Zn were found. Main sources of metals were defined as: tire wearing for Zn and Fe; brake wearing for Ba, Cu, Fe, Pb and Zr; additional industrial sources for Mo, Ni, Pb, and Ti; and other natural sources for As. Ecological risk was found to be moderate across the city and risk due to Pb concentrations was established for children.

Prevalence, geographic distribution and phenotypic differences of Piscirickettsia salmonis EM-90-like isolates

Early reports accounted for two main genotypes of Piscirickettsia salmonis, a fish pathogen and causative agent of piscirickettsiosis, placing the single isolate EM-90 apart from the prototypic LF-89 and related isolates. In this study, we provide evidence that, contrary to what has been supposed, the EM-90-like isolates are highly prevalent and disseminated across Chilean marine farms. Molecular analysis of 507 P. salmonis field isolates derived from main rearing areas, diverse hosts and collected over 6 years, revealed that nearly 50% of the entire collection were indeed typed as EM-90-like. Interestingly, these isolates showed a marked host preference, being recovered exclusively from Atlantic salmon (Salmo salar) samples. Although both strains produce undistinguishable pathological outcomes, differences regarding growth kinetics and susceptibility to the antibiotics and bactericidal action of serum could be identified. In sum, our results allow to conclude that the EM-90-like isolates represent an epidemiologically relevant group in the current situation of piscirickettsiosis. Based on the consistency between genotype and phenotype exhibited by this strain, we point out the need for genotypic studies that may be as important for the Chilean salmon industry as the continuous surveillance of antimicrobial susceptibility patterns.

Prevalence, geographic distribution and phenotypic differences of Piscirickettsia salmonis EM-90-like isolates

Early reports accounted for two main genotypes of Piscirickettsia salmonis, a fish pathogen and causative agent of piscirickettsiosis, placing the single isolate EM-90 apart from the prototypic LF-89 and related isolates. In this study, we provide evidence that, contrary to what has been supposed, the EM-90-like isolates are highly prevalent and disseminated across Chilean marine farms. Molecular analysis of 507 P. salmonis field isolates derived from main rearing areas, diverse hosts and collected over 6 years, revealed that nearly 50% of the entire collection were indeed typed as EM-90-like. Interestingly, these isolates showed a marked host preference, being recovered exclusively from Atlantic salmon (Salmo salar) samples. Although both strains produce undistinguishable pathological outcomes, differences regarding growth kinetics and susceptibility to the antibiotics and bactericidal action of serum could be identified. In sum, our results allow to conclude that the EM-90-like isolates represent an epidemiologically relevant group in the current situation of piscirickettsiosis. Based on the consistency between genotype and phenotype exhibited by this strain, we point out the need for genotypic studies that may be as important for the Chilean salmon industry as the continuous surveillance of antimicrobial susceptibility patterns.

Results From the Imaging and Radiation Oncology Core Houston's Anthropomorphic Phantoms Used for Proton Therapy Clinical Trial Credentialing

PURPOSE

The purpose of this study was to summarize the findings of anthropomorphic proton phantom irradiations analyzed by the Imaging and Radiation Oncology Core Houston QA Center (IROC Houston).

METHODS AND MATERIALS

A total of 103 phantoms were irradiated by proton therapy centers participating in clinical trials. The anthropomorphic phantoms simulated heterogeneous anatomy of a head, liver, lung, prostate, and spine. Treatment plans included those for scattered, uniform scanning, and pencil beam scanning beam delivery modalities using 5 different treatment planning systems. For every phantom irradiation, point doses and planar doses were measured using thermoluminescent dosimeters (TLD) and film, respectively. Differences between measured and planned doses were studied as a function of phantom, beam delivery modality, motion, repeat attempt, treatment planning system, and date of irradiation.

RESULTS

The phantom pass rate (overall, 79%) was high for simple phantoms and lower for phantoms that introduced higher levels of difficulty, such as motion, multiple targets, or increased heterogeneity. All treatment planning systems overestimated dose to the target, compared to TLD measurements. Errors in range calculation resulted in several failed phantoms. There was no correlation between treatment planning system and pass rate. The pass rates for each individual phantom are not improving over time, but when individual institutions received feedback about failed phantom irradiations, pass rates did improve.

CONCLUSIONS

The proton phantom pass rates are not as high as desired and emphasize potential deficiencies in proton therapy planning and/or delivery. There are many areas for improvement with the proton phantom irradiations, such as treatment planning system dose agreement, range calculations, accounting for motion, and irradiation of multiple targets.

Prevention of infectious complications of percutaneous nephrolithotomy

Infection and sepsis is a complication of percutaneous nephrolithotomy that can lead to morbidity, mortality, and increased costs. Herein we review the current relevant literature on the topic of prevention of sepsis after percutaneous nephrolithotomy.