Abstract 4145497: Pump-Assisted Vein Dilation for Arteriovenous Fistula Creation – Translation of the Amplifi Vein Dilation System from Bench to Bedside
Background: Autologous arteriovenous fistulas (AVF) are the preferred choice for hemodialysis access due to their longevity, lower complication rates, and mortality benefit. Their use is limited by vein size and necessary maturation period, excluding up to a third of patients. A novel solution to this problem is pump-assisted vein dilation (PAVD), where the vein is “pre-matured” using a miniatured centrifugal pump that draws blood from a central vein, delivering it into the recipient vein (e.g., cephalic) under pressure. The aim of this study is to report the initial safety studies in sheep and a first-in-human (FIH) pilot study as a prelude to a phase 2 clinical study. Methods: Preclinical Study: Three anesthetized male sheep (50-70 kg) underwent cephalic PAVD using the Amplifi Vein Dilation System for 7 days (mean). These subjects and two control animals (no-PAVD) underwent brachiocephalic AVF creation and observation for 6 weeks, with weekly surveillance fistulagrams and duplex ultrasound (U/S). AVFs were then explanted for histological analysis. Clinical Study: Ten patients were recruited for a phase 1 study. They underwent cephalic PAVD for 7 days (mean), followed by brachiocephalic AVF creation and surveillance at 2 and 6 wks. Data on vein diameter and flow rates of the AVF were collected, as well as safety data on complications such as bleeding, infection, and embolism. Results: Preclinical Study: PAVD increased mean±SD vein diameter (mm) from 4.5±1.0 to 8.4±1.0 (p=0.005); leading to greater cephalic vein diameter at the time of AVF creation in the PAVD group vs no-PAVD (8.2±1.3 vs. 3.3±0.7; p<0.05). After 6 wks of maturation, mean vein diameter was still greater in the PAVD group compared to no-PAVD (12.8±2.8 vs. 8.4±0.7; p<0.05). Mean flow increased at 41 mL/min/day versus control animals at 5.2 mL/min/day. Clinical Study: All subjects saw an increase in vein diameter with PAVD at baseline vs. at 6 wks (2.3±0.5 vs. 5.2±0.7; p<0.05), as well as mean flows (mL/min) (285±30 vs. 724±149). There were no Amplifi-related or procedure-related serious adverse events. Conclusion: The translation of PAVD for AVF creation from bench-to-bedside provides safety and efficacy data on a novel solution that can increase the availability of autologous AVFs in patients excluded due to size criteria. The Amplifi vein dilation system can effectively and rapidly dilate peripheral veins without stimulating neointimal hyperplasia. PAVD should be explored in a phase 2 clinical study.
Pre-operative Management of Myasthenia Gravis in Patients Undergoing Surgery (P6.430)
BACKGROUND: Patients with existing coronary artery stents are at an increased risk for major adverse cardiac events (MACEs) when undergoing noncardiac surgery (NCS). Although the use of antifibrinolytic (AF) therapy in NCS has significantly increased in the past decade, the relationship between perioperative AF use and its association with MACEs among patients with existing coronary artery stents has yet to be assessed. In this study, we aim to evaluate the association of MACEs in patients with existing coronary artery stents who receive perioperative AF therapy during orthopedic surgery. METHODS: A single-center retrospective cohort study was conducted in adult patients with existing coronary artery stents who underwent orthopedic surgery from 2008 to 2018. Two cohorts were established: patients with existing coronary artery stents who did not receive perioperative AF and patients with coronary artery stents who received perioperative AF. Associations between AF use and the primary outcome of MACEs within 30 days postoperatively and the secondary outcomes of thrombotic complications, excessive surgical bleeding, and intensive care unit (ICU) admissions were analyzed using logistic regression models. Inverse probability of treatment weighting was used to control for confounding. Secondary analyses examining the association between coronary stent type/timing and the outcomes of interest were performed using unadjusted logistic regression models. RESULTS: A total of 473 patients met study criteria, including 294 who did not receive AF and 179 patients who received AF. MACEs occurred in 15 (5.1%) patients who did not receive AF and 1 (0.6%) who received AF ( P = .007). In weighted analyses, no significant difference was found in patients who received AF with regard to MACEs (odds ratio [OR] = 0.13, 95% confidence interval [CI], 0.01-1.74, P = .12), thrombotic complications (OR = 1.19, 95% CI, 0.53-2.68, P = .68), or excessive surgical bleeding (OR = 0.13, 95% CI, 0.01-2.23, P = .16) compared to patients who did not receive AF. CONCLUSIONS: The results of this study are inconclusive whether an association exists between perioperative AF use in patients with coronary artery stents and the outcome of MACEs compared to patients who did not receive perioperative AF therapy. The authors acknowledge that the imprecise CI hinders the ability to definitively determine whether an association exists in the study population. Further large prospective studies, powered to detect differences in MACEs, are needed to assess the safety of perioperative AF in patients with existing coronary artery stents and to clarify the mechanism of perioperative MACEs in this high-risk population.
Inclusion of Thyroid Nodule Location in American College of Radiology TI-RADS Scoring: Impact on System Performance
Abstract INTRODUCTION Optic nerve sheath meningiomas (ONSMs) are often managed with radiotherapy (RT) with the goal of achieving radiographic local control (LC) to prevent further decline in visual acuity (VA); however, reports on outcomes are limited to small retrospective series. Thus, we aimed to perform a systematic review and meta-analysis of outcomes for patients with ONSM treated with RT. METHODS A PICOS/PRISMA/MOOSE selection criteria was utilized to identify studies for inclusion. Primary outcomes were stable or improved VA and radiographic LC at last follow-up. The secondary outcome was incidence of radiation-induced retinopathy. Weighted random effects meta-analyses using the DerSimonian and Laird methods were conducted to characterize effect sizes. Mixed effects regression models were used to examine potential correlations between gross tumor volume (GTV) and outcomes. RESULTS In total, 381 patients with ONSM across 18 published studies were included. Of these, 332 and 386 treated ONSMs had information on VA or LC, respectively. Median age was 46.75 (range: 9-87), median/mean GTV was 2.905cc (range: 0.28-26.3), and median follow-up was 51.15 months (range: 1-248.4 months). The estimated LC rate at last follow-up was 100% (95% CI: 98-100%), and the estimated proportion of patients with stable or improved VA at last follow-up was 89% (95% CI: 84-93%). The rate of chronic radiation retinopathy was estimated to be 7% (95% CI: 5-11%). GTV was significantly associated with VA (p=0.014) with estimated VA rates of 96.4%, 91.4%, and 80.5% for GTVs of 2.0, 3.0, and 4.0ccs, respectively. CONCLUSIONS RT was well-tolerated in the treatment of ONSM with excellent LC achieved. Nearly 90% of patients noted either stability or improvement in VA. Larger ONSMs were found to be associated with poorer VA. Incidences of radiation-induced retinopathy were limited and estimated to be less than 10%.
Peripheral Nerve Blockade with Combined Standard and Liposomal Bupivacaine in Major Lower‐Extremity Amputation
AbstractBackground and ObjectivesOptimizing perioperative analgesia for patients undergoing major lower‐extremity amputation remains a considerable challenge. The utility of liposomal bupivacaine as a component of peripheral nerve blockade for lower‐extremity amputation is unknown.MethodsWe conducted an observational study comparing three different perioperative analgesic techniques for adults undergoing major lower‐extremity amputation under general anesthesia between 2012 and 2017 at an academic medical center: (1) no regional anesthesia, (2) peripheral nerve blockade with standard bupivacaine, and (3) peripheral nerve blockade with a mixture of standard and liposomal bupivacaine. The primary outcome of cumulative opioid oral morphine milligram equivalent utilization in the first 72 hours postoperatively was compared across groups utilizing multivariable linear regression.ResultsA total of 631 unique anesthetics were included for 578 unique patients, including 416 (66%) without regional anesthesia, 131 (21%) with peripheral nerve blockade with a mixture of standard and liposomal bupivacaine, and 84 (13%) with peripheral nerve blockade with standard bupivacaine alone. Cumulative morphine equivalents were lower in those receiving peripheral nerve blockade with combined standard and liposomal bupivacaine compared with those not receiving regional anesthesia (multiplicative increase 0.67; 95% CI 0.50 to 0.90; P = 0.007). There were no significant differences in opioid utilization between peripheral nerve blockade groups (P = 0.59).ConclusionsPeripheral nerve blockade is associated with reduced opioid requirements after lower‐extremity amputation compared with general anesthesia alone. However, the incorporation of liposomal bupivacaine is not significantly different to blockade employing only standard bupivacaine.
Analysis of Malignant Thyroid Nodules That Do Not Meet ACR TI-RADS Criteria for Fine-Needle Aspiration
Abstract Background: The Philadelphia chromosome negative chronic myeloproliferativeneoplasms (MPNs) including essential thrombocythemia (ET), polycythemia vera(PV), and myelofibrosis (MF) are a group of diseases of myeloid clonal lineage with significant symptom burden. MPN patients have also been found to have a high likelihood of mood disturbance related to their MPN, including symptoms of depression and anxiety (BMC Cancer. 201616:167). To date, the relationship between disease factors and depressive symptoms among MPN patients has not been well characterized. Methods: We have previously published the results of a 70-item internet-based survey which evaluated fatigue-relieving strategies among MPN patients (Cancer. 2016 Feb 1;122(3):477-85). Surveyed data included mental health questionnaires including a measure of symptoms of depression, the PHQ-2, (Ann Fam Med. 2010. 8(4): 348-353), a measure of positive and negative moods the POMS-short form (J Nerv Ment Dis. 1979;167(10):612-4) and a measure of symptoms of depression and anxiety, the MHI-5 (J Consult Clin Psychol. 1983. 51;730-742). This abstract is a secondary analysis of data collected among this cohort. Data: Demographics A total of 1788 individuals diagnosed with an MPN participated in the survey. 1389 patients answered questions regarding mood and psychological comorbidities. Many MPN patients reportedthat they had been seen by a health provider for care or diagnosis of depression (32%), anxiety (29.5%), stress (26.2%), or grief(15.0%). Overall, 24.0% of ET, 22.2% of PV, and 22.9% of MF patients endorsed symptoms of depression based on their score of greater than or equal to 3 on the PHQ-2. Demographic and Psychosocial Correlates Younger patients were significantly more likely to have PHQ-2 score of equal to or greater than three (57.0 years vs 59.5 years, p=0.0006). Gender, race, and country of origin did not significantly correlate with screening positive for symptoms of depression. Higher BMI was associated with a higher likelihood of screening positive for symptoms of depression (BMI 26.2 vs 24.6, p=0.005). Not surprisingly, having received treatment for mood problems in the last 6 months (p<0.0001) along with medications for mood disorders (p=0.03) were significantly associated with increased symptoms of depression. Specifically, the use of psychostimulants (p<0.0001), antidepressants (p<0.0001), anti-anxiety medications (p=0.0005) and prescription pain medications (p<0.001), were significantly associated with elevated PHQ-2 score. Individuals with lower educational attainment were more likely to endorse depressive symptoms (p=0.0001) as well as those who were unable to work from home due to a medical disability (p<0.0001). Tobacco use was significantly associated with depressive symptoms (p=0.0002). Symptom and Mental Health Correlates Increased MPN-SAF TSS (MPN-10) score and all individual symptom items in the MPN-SAF were significantly associated with symptoms of depression (p<0.0001, Table 1). Increased POMS-B Subscales scores and total score along with lower MHI score was associated with positive depression screening. When asking patients what interventions they had tried to reduce fatigue, those who endorsed volunteer activities (18% vs 25.4%, p= 0.0062) and exercise (19.7% vs 32.2, p<0.0001) were significantly less likely to screen positive for symptoms of depression. Prognostic Risk Scoring Correlates For MF, PV and ET prognostic risk scoring did not significantly correlate with PHQ score (for all, P>0.005). Conclusions Depression and mood disorders among individuals with malignancy represent a particular challenge for health care providers, particularly in MPN patients who have been found to have a higher risk of depression than the general population. In our cohort, prognostic risk did not correlate with risk of depression. Based on these findings, it is critical that physicians who see MPN patients should closely monitor these patients for signs of depression and provide appropriate treatment when needed. Continued investigation into treatment of mood disorders among MPN patients is warranted, as patients may benefit from both symptom-directed therapies as well as traditional therapies. Encouragement of volunteering and exercise activities should be considered for thesepatientsas participation may be associated with improved mood status. Disclosures Harrison: Novartis: Consultancy, Honoraria, Other: travel, accommodations, expenses, Research Funding, Speakers Bureau; Shire: Honoraria, Speakers Bureau; Gilead: Honoraria, Speakers Bureau; Baxaltra: Consultancy, Honoraria, Speakers Bureau; Incyte Corporation: Honoraria, Speakers Bureau. Mesa:Galena: Consultancy; Incyte: Research Funding; Gilead: Research Funding; Novartis: Consultancy; CTI: Research Funding; Promedior: Research Funding; Ariad: Consultancy; Celgene: Research Funding.