Experience with the utilization of new-generation shared-control robotic system for spinal instrumentation

BACKGROUND

Robotic assistance in spine surgery is emerging as an accurate, effective and enabling technology utilized in the treatment of patients with surgical spinal pathology. The safety and reproducibility of robotic assistance in the placement of pedicle screw instrumentation is still being investigated. The objective of this study was to present our experience of instrumented spinal fusion utilizing an intraoperative robotic guidance system.

METHODS

We retrospectively reviewed all cases of spinal instrumentation of the thoracic and lumbo-sacral spine using the Mazor X robotic system (Medtronic Inc, Minneapolis, MN, USA), performed at our institution by one surgeon between July 2017 and June 2020. Wilcoxon Rank test was used to compare time taken to place each screw during the first 20 cases and the cases thereafter.

RESULTS

A total of 28 patients were included. A total of 159 screws were placed using the Mazor X robotic system. The overall mean time for screw placement was 7.8±2.3 minutes and there was a significant reduction in the mean time for screw placement after the 20th case or 120 screws (8.70 vs. 5.42 min, P=0.008). No postoperative neurologic deficit or new radiculopathy was noted to occur secondary to hardware placement. No revision surgery was required for replacement or removal of a mispositioned screw.

CONCLUSIONS

From this single-center, single-surgeon series we conclude that robot-assisted spine surgery can be safely and efficiently integrated into the operating room workflow, which improves after a learning curve of approximately 20 operative interventions. We found robot-assisted spinal instrumentation to be reliable, safe, effective and highly precise.

Type II odontoid fractures in the elderly presenting to the emergency department: an assessment of factors affecting in-hospital mortality and discharge to skilled nursing facilities

BACKGROUND CONTEXT

Type II odontoid fractures (OF) are among the most common cervical spine injuries in the geriatric population. However, there is a paucity of literature regarding their epidemiology. Additionally, the optimal management of these injuries remains controversial, and no study has evaluated the short-term outcomes of geriatric patients presenting to emergency departments (ED).

PURPOSE

This study aims to document the epidemiology of geriatric patients presenting to EDs with type II OFs and determine whether surgical management was associated with early adverse outcomes such as in-hospital mortality and discharge to skilled nursing facilities (SNF).

STUDY DESIGN

This is a retrospective cohort study.

PATIENT SAMPLE

Data was used from the 2016-2020 Nationwide Emergency Department Sample. Patient encounters corresponding to type II OFs were identified. Patients younger than 65 at the time of presentation to the ED and those with concomitant spinal pathology were excluded.

OUTCOME MEASURES

The association between the surgical management of geriatric type II OFs and outcomes such as in-hospital mortality and discharge to SNFs.

METHODS

Patient, fracture, and surgical management characteristics were recorded. A propensity score matched cohort was constructed to reduce differences in age, comorbidities, and injury severity between patients undergoing operative and nonoperative management. Additionally, to develop a positive control for the analysis of geriatric patients with type II OFs and no other concomitant spinal pathology, a cohort of patients that had been excluded due to the presence of a concomitant spinal cord injury (SCI) was also constructed. Multivariate regressions were then performed on both the matched and unmatched cohorts to ascertain the associations between surgical treatment and in-hospital mortality, inpatient length of stay, encounter charges, and discharge to SNFs.

RESULTS

A total of 11,325 encounters were included. The mean total charge per encounter was $60,221. 634 (5.6%) patients passed away during their encounters. In total, 1,005 (8.9%) patients were managed surgically. Surgical management of type II OFs was associated with a 316% increase in visit charge (95% CI: 291%-341%, p<.001), increased inpatient length of stay (IRR: 2.87, 95% CI: 2.62-3.12, p<.001), and increased likelihood of discharge to SNFs (OR=2.62, 95% CI: 2.26-3.05, p<.001), but decreased in-hospital mortality (OR=0.32, CI: 0.21-0.45, p<.001). The propensity score matched cohort consisted of 2,010 patients, matching each of the 1,005 that underwent surgery to 1,005 that did not. These cohorts were well balanced across age (78.24 vs 77.91 years), Elixhauser Comorbidity Index (3.68 vs 3.71), and Injury Severity Score (30.15 vs 28.93). This matching did not meaningfully alter the associations determined between surgical management and in-hospital mortality (OR=0.34, CI=0.21-0.55, p<.001) or SNF discharge (OR=2.59, CI=2.13-3.16, p<.001). Lastly, the positive control cohort of patients with concurrent SCI had higher rates of SNF discharge (50.0% vs 42.6%, p<.001), surgical management (32.3% vs 9.7%, p<.001), and in-hospital mortality (28.9% vs 5.6%, p<.001).

CONCLUSIONS

This study lends insight into the epidemiology of geriatric type II OFs and quantifies risk factors influencing adverse outcomes. Patient informed consent should include a discussion of the protective association between definitive surgical management and in-hospital mortality against potential operative morbidity, increased lengths of hospital stay, and increased likelihood of discharge to SNFs. This information may impact patient treatment selection and decision making.

Misplaced intraspinal venous stent causing cauda equina syndrome: illustrative case

BACKGROUND

Endovenous stents for deep venous thrombosis treatment can be unintentionally placed in the spinal canal, resulting in neurological deficit.

OBSERVATIONS

The authors report the case of a patient presenting to our institution with intraspinal misplacement of an endovenous stent, resulting in cauda equina syndrome. The authors also performed a systematic literature review, evaluating the few previously reported cases. This review was performed according to the updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. In four of five cases describing stent misplacement into the spinal canal, the authors report that only anteroposterior monoplanar imaging modalities were utilized for venous localization and stent deployment. The anteroposterior plane cannot assess the relative depth of structures, nor can it distinguish between superimposed structures well. Therefore, the use of biplanar imaging should at least be considered before stent deployment, as intraspinal stent placement can lead to disastrous consequences.

LESSONS

This report should serve as an impetus for the use of biplanar or three-dimensional imaging modalities for iliac venous stent placement. Additionally, this work should increase spine surgeons' awareness about management and operative techniques when faced with this complication.

Machine Learning in Neurosurgery: Toward Complex Inputs, Actionable Predictions, and Generalizable Translations

Machine learning can predict neurosurgical diagnosis and outcomes, power imaging analysis, and perform robotic navigation and tumor labeling. State-of-the-art models can reconstruct and generate images, predict surgical events from video, and assist in intraoperative decision-making. In this review, we will detail the neurosurgical applications of machine learning, ranging from simple to advanced models, and their potential to transform patient care. As machine learning techniques, outputs, and methods become increasingly complex, their performance is often more impactful yet increasingly difficult to evaluate. We aim to introduce these advancements to the neurosurgical audience while suggesting major potential roadblocks to their safe and effective translation. Unlike the previous generation of machine learning in neurosurgery, the safe translation of recent advancements will be contingent on neurosurgeons' involvement in model development and validation.

Accuracy of predicted postoperative segmental lumbar lordosis in spinal fusion using an intraoperative robotic planning and guidance system

BACKGROUND

Restoring lumbar lordosis is one of the main goals in lumbar spinal fusion surgery. The Mazor X-AlignTM software allows for the prediction of postoperative segmental lumbar lordosis based on preoperative imaging. There is limited data on the accuracy of this preoperative prediction, especially in patients undergoing short segment lumbar fusion. The objective of our study was to determine the accuracy of predicted postoperative segmental lumbar lordosis using the Mazor X-AlignTM software in patients requiring short segmental fusion.

METHODS

Retrospective analysis of adult patients undergoing pedicle screw spinal instrumentation of not more than four levels using the Mazor XTM Robot (Medtronic Inc., Minneapolis, MN, USA) between July 2017 to June 2020. The robotic guidance software, Mazor X-AlignTM (Medtronic Inc., Minneapolis, MN, USA) was used to calculate the predicted segmental lumbar lordosis based on preoperative CT-imaging and the plan was executed under intraoperative robotic guidance. Predicted segmental lumbar lordosis was compared to achieved segmental lumbar lordosis on 1-month postoperative x-rays using the Cobb angle methodology.

RESULTS

A total of 15 patients (46.6% female) with a mean age of 61.5±10.9 years were included. All patients underwent posterior lumbo-sacral spinal fusion with the Mazor XTM robotic system with 11 patients (73.3%) undergoing anterior column reconstruction prior to posterior fixation. Instrumentation was performed across a mean of 2.6 levels per case. Preoperative, the mean segmental lumbar lordosis was 30.2±13.6 degrees. The mean planned segmental lumbar lordosis was 35.5±17.0 degrees while the mean achieved segmental lumbar lordosis was 35.8±16.7 degrees. There was no significant mean difference between the planned and achieved segmental lumbar lordosis (P=0.334).

CONCLUSIONS

The Mazor XTM intraoperative robotic planning and guidance is accurate in predicting postoperative segmental lumbar lordosis after short segmental fusion. Our findings may assure surgical decision making and planning.

Common Neuroimaging Findings in Bosch-Boonstra-Schaaf Optic Atrophy Syndrome

Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS) is a rare autosomal dominant syndrome secondary to mutations in NR2F1 (COUP-TF1), characterized by visual impairment secondary to optic nerve hypoplasia and/or atrophy, developmental and cognitive delay, and seizures. This study reports common neuroimaging findings in a cohort of 21 individuals with BBSOAS that collectively suggest the diagnosis. These include mesial temporal dysgyria, perisylvian dysgyria, posterior predominant white matter volume loss, callosal abnormalities, lacrimal gland abnormalities, and optic nerve volume loss.

Polyvinylpyrrolidone-Coated Catheters Decrease Astrocyte Adhesion and Improve Flow/Pressure Performance in an Invitro Model of Hydrocephalus

The leading cause of ventricular shunt failure in pediatric patients is proximal catheter occlusion. Here, we evaluate various types of shunt catheters to assess in vitro cellular adhesion and obstruction. The following four types of catheters were tested: (1) antibiotic- and barium-impregnated, (2) polyvinylpyrrolidone, (3) barium stripe, and (4) barium impregnated. Catheters were either seeded superficially with astrocyte cells to test cellular adhesion or inoculated with cultured astrocytes into the catheters to test catheter performance under obstruction conditions. Ventricular catheters were placed into a three-dimensional printed phantom ventricular replicating system through which artificial CSF was pumped. Differential pressure sensors were used to measure catheter performance. Polyvinylpyrrolidone catheters had the lowest median cell attachment compared to antibiotic-impregnated (18 cells), barium stripe (17 cells), and barium-impregnated (21.5 cells) catheters after culture (p < 0.01). In addition, polyvinylpyrrolidone catheters had significantly higher flow in the phantom ventricular system (0.12 mL/min) compared to the antibiotic coated (0.10 mL/min), barium stripe (0.02 mL/min) and barium-impregnated (0.08 mL/min; p < 0.01) catheters. Polyvinylpyrrolidone catheters showed less cellular adhesion and were least likely to be occluded by astrocyte cells. Our findings can help suggest patient-appropriate proximal ventricular catheters for clinical use.

Factors influencing treatment outcomes in patients with isoniazid-resistant pulmonary TB

INTRODUCTION: Patients with isoniazid (H, INH) resistant pulmonary TB but undetected rifampicin (R, RIF) resistance are treated with a 6-month regimen of levofloxacin-RIF-ethambutol-pyrazinamide (6LvxREZ) under India´s National TB Elimination Programme (NTEP).OBJECTIVE: To describe the profile of and treatment outcomes in patients with pulmonary INH-resistant (INHR) TB initiated on TB treatment, and identify factors associated with unfavourable treatment outcomes (died, failed, treatment changed, lost to follow-up).METHODS: This was a retrospective analysis of NTEP database (Ni-kshay) on pulmonary INHR TB patients initiated on treatment with “H mono/poly regimen” (6LvxREZ) between July 2019 and June 2020 with documented treatment outcomes. Proportions with 95% confidence interval (CI) was calculated and logistic regression analysis was performed.RESULTS: Of the 11,519 patients with pulmonary INHR TB, 9,440 (82%) had treatment success (55.1% cured, 26.9% treatment completed). Unfavourable treatment outcome was observed in 1,901 (16.5%). Male sex, tobacco and alcohol use, HIV reactive status were associated with unfavourable treatment outcome. Patients with katG mutations and resistance to fluoroquinolones were likely to have poor treatment outcomes.CONCLUSION: A levofloxacin-based regimen offers a treatment success rate of 82% in patients with pulmonary INHR TB. Sex-specific strategies, interventions to address smoking and alcohol use, focus on HIV-reactive patients and optimising treatment regimens based on drug susceptibility should be considered for improving treatment outcomes.

LB0004 EFFICACY AND SAFETY OF DEUCRAVACITINIB, AN ORAL, SELECTIVE, ALLOSTERIC TYK2 INHIBITOR, IN PATIENTS WITH ACTIVE SYSTEMIC LUPUS ERYTHEMATOSUS: A PHASE 2, RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED STUDY

Background

Tyrosine kinase 2 (TYK2) mediates signaling of Type I interferons, IL-23, and IL-12, key cytokines involved in lupus pathogenesis. Deucravacitinib (DEUC) is an oral, selective, allosteric TYK2 inhibitor with a unique mechanism of action, distinct from Janus kinase (JAK) 1/2/3 inhibitors, and has shown efficacy in psoriasis and psoriatic arthritis.

Objectives

Assess efficacy and safety of DEUC in patients with active systemic lupus erythematosus (SLE).

Methods

This was a 48-week (wk), randomized, double-blind, placebo (PBO)-controlled, phase 2 trial (NCT03252587). Eligible patients met SLICC criteria, were seropositive (ANA/anti-dsDNA/anti-Sm), and had a SLEDAI-2K score ≥6 and ≥1 BILAG index A or >2 BILAG B manifestations from the musculoskeletal or mucocutaneous domain. Patients on standard background medications were randomized 1:1:1:1 to PBO or DEUC (3 mg BID, 6 mg BID, 12 mg QD). Oral corticosteroid tapering to 7.5 mg/day was required from wks 8-20; further tapering was optional from wks 32-40. The primary endpoint was the proportion of patients achieving SRI(4) at wk 32. Key secondary endpoints at wk 48 included SRI(4), BICLA, LLDAS, CLASI-50, and change from baseline in active (tender and swollen) joint count.

Results

A total of 363 patients were randomized, with baseline demographic and disease characteristics similar across treatment groups. Of randomized patients, 275 (76%) completed 48 wks of treatment. The primary endpoint at wk 32 was met, with significantly greater proportion of patients in DEUC 3 mg BID and 6 mg BID groups vs PBO achieving SRI(4) responses (PBO: 34.4%; DEUC 3 mg BID: 58.2%, P=0.0006; DEUC 6 mg BID: 49.5%, P=0.021; DEUC 12 mg QD: 44.9%, P=0.078). SRI(4) response was sustained across all DEUC groups up to 48 wks (Figure 1). At wk 48, the DEUC 3 mg BID group demonstrated statistical significance in BICLA, LLDAS, CLASI-50, and active joint count, and the two other DEUC groups demonstrated clinically meaningful differences vs PBO (Figure 1). Rates of adverse events (AEs), serious AEs, and AEs of interest were similar between DEUC and PBO groups (Table 1). Most common AEs (≥10%) with DEUC were upper respiratory tract infection, nasopharyngitis, headache, and urinary tract infection. No deaths, major cardiac events, thrombotic events, systemic opportunistic infections, or active tuberculosis occurred. Malignancies were rare with similar rates across all groups. No meaningful abnormalities in mean levels of hematology and chemistry laboratory parameters were observed.

Table 1.

Summary of Adverse Events Through Week 48

AE, na(%)Placebo n = 90DEUC 3 mg BID n = 91DEUC 6 mg BID n = 93DEUC 12 mg QD n = 89AE79 (87.8)85 (93.4)81 (87.1)75 (84.3)SAE11 (12.2)7 (7.7)8 (8.6)7 (7.9)AEs leading to treatment discontinuation3 (3.3)8 (8.8)6 (6.5)11 (12.4)Skin-related AEsb12 (13.3)15 (16.5)32 (34.4)30 (33.7)Overall infections/infestations48 (53.3)60 (65.9)60 (64.5)45 (50.6)Serious infections/infestations1 (1.1)1 (1.1)2 (2.2)1 (1.1)Infections of interest Tuberculosis0000 Herpes zosterc4 (4.4)3 (3.3)3 (3.2)2 (2.2) Influenza1 (1.1)3 (3.3)1 (1.1)3 (3.4) COVID-193 (3.3)3 (3.3)5 (5.4)3 (3.4)Malignancy events1 (1.1)d1 (1.1)e01 (1.1)fMACE0000Thrombotic events0000

an is the number of patients who experienced an event. bIncludes (≤8.6% in any arm) acne, rash, dermatitis acneiform, pruritus, skin lesion, urticaria. cIncludes herpes zoster, herpes ophthalmic, genital herpes zoster. dBasal cell carcinoma. eBreast carcinoma. fVaginal squamous cell carcinoma.

AE, adverse event; COVID-19, coronavirus disease 2019; DEUC, deucravacitinib; MACE, major adverse cardiac events; SAE, serious adverse event.

Conclusion

In patients with active SLE, DEUC showed statistically significant and sustained clinical efficacy in SRI(4), improvement across multiple composite and organ-specific measures up to 48 wks, and was well tolerated. DEUC shows promise as a novel therapy for SLE and warrants further investigation in phase 3 trials.

Acknowledgements

This study was sponsored by Bristol Myers Squibb. Professional medical writing assistance was provided by Julianne Hatfield, PhD at Peloton Advantage, LLC, an OPEN Health company, Parsippany, NJ, USA, and funded by Bristol Myers Squibb. The authors acknowledge Christina Crater, MD, who was employed by Bristol Myers Squibb at the time the study was conducted, for contributions to study conduct.

Disclosure of Interests

Eric Morand Consultant of: AstraZeneca, Bristol Myers Squibb, Biogen, Eli Lilly, EMD Serono, Genentech, Servier, and Novartis , Grant/research support from: AbbVie, Amgen, AstraZeneca, Bristol Myers Squibb, Biogen, Eli Lilly, EMD Serono, Genentech, Janssen, and UCB , Marilyn Pike Consultant of: AstraZeneca, Bristol Myers Squibb, and Pfizer, Joan T. Merrill Consultant of: UCB, GlaxoSmithKline, AbbVie, EMD Serono, Remegen, Celgene/Bristol Myers Squibb, AstraZeneca, Amgen, Janssen, Lilly, Genentech, Aurinia, Astellas, Alexion, Sanofi, Zenas, and Provention , Grant/research support from: GlaxoSmithKline and AstraZeneca , Ronald van Vollenhoven Consultant of: UCB, Pfizer, AbbVie, AstraZeneca, Biogen, Biotest, Celgene, Galapagos, Gilead, Janssen, Servier, Paid instructor for: Roche, Pfizer, Speakers bureau: UCB, Pfizer, AbbVie, Galapagos, Janssen, Grant/research support from: Bristol Myers Squibb, GlaxoSmithKline, Eli Lilly, UCB, , Victoria P. Werth Consultant of: Celgene, Medimmune, Resolve, Genentech, Idera, Janssen, Lilly, Biogen, Bristol Myers Squibb, Gilead, Amgen, Medscape, Nektar, Incyte, EMD Serono, CSL Behring, Principia, Crisalis, Viela Bio, Argenx, Kirin, AstraZeneca, AbbVie, GSK, AstraZeneca, Cugene, UCB, Corcept, Beacon Bioscience , Grant/research support from: Celgene, Janssen, Biogen, Gilead, AstraZeneca, Viela, Amgen, Lupus Research Alliance/BMS , Coburn Hobar Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Nikolay Delev Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Vaishali Shah Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Brian Sharkey Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Thomas Wegman Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Ian Catlett Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Subhashis Banerjee Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Shalabh Singhal Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb

Algorithmic Prediction of Delayed Radiology Turn-Around-Time during Non-Business Hours

RATIONALE AND OBJECTIVES

Radiology turnaround time is an important quality measure that can impact hospital workflow and patient outcomes. We aimed to develop a machine learning model to predict delayed turnaround time during non-business hours and identify factors that contribute to this delay.

MATERIALS AND METHODS

This retrospective study consisted of 15,117 CT cases from May 2018 to May 2019 during non-business hours at two hospital campuses after applying exclusion criteria. Of these 15,177 cases, 7,532 were inpatient cases and 7,585 were emergency cases. Order time, scan time, first communication by radiologist, free-text indications, and other clinical metadata were extracted. A combined XGBoost classifier and Random Forest natural language processing model was trained with 85% of the data and tested with 15% of the data. The model predicted two measures of delay: when the exam was ordered to first communication (total time) and when the scan was completed to first communication (interpretation time). The model was analyzed with the area under the curve (AUC) of receiver operating characteristic (ROC) and feature importance. Source code: https://bit.ly/2UrLiVJ RESULTS: The algorithm reached an AUC of 0.85, with a 95% confidence interval [0.83, 0.87], when predicting delays greater than 245 minutes for "total time" and 0.71, with a 95% confidence interval [0.68, 0.73], when predicting delays greater than 57 minutes for "interpretation time". At our institution, CT scan description (e.g. "CTA chest pulmonary embolism protocol"), time of day, and year in training were more predictive features compared to body part, inpatient status, and hospital campus for both interpretation and total time delay.

CONCLUSION

This algorithm can be applied clinically when a physician is ordering the scan to reasonably predict delayed turnaround time. Such a model can be leveraged to identify factors associated with delays and emphasize areas for improvement to patient outcomes.

The impact of outdoor walking surfaces on lower-limb coordination and variability during gait in healthy adults

BACKGROUND

Inter-joint coordination and variability during gait provide insight into control and adaptability of the neuromuscular system. To date, coordination research has been restricted to laboratory settings, and it is unclear how these findings translate to real-world, outdoor walking environments.

RESEARCH QUESTION

Compared to flat walking, to what extent do outdoor surfaces impact lower-limb inter-joint coordination and variability during gait, in healthy adults?

METHODS

Data from inertial measurement units placed on the lower-back, thigh, and shank were extracted from thirty healthy young adults (15 females, 23.5 ± 4.2 years) during outdoor walking on flat (paved sidewalk); irregular (cobblestone, grass); sloped (slope-up, slope-down); and banked (banked-right, banked-left) surfaces. Sagittal joint angles for the right knee and hip were computed and partitioned by gait phase (stance and swing). Continuous Relative Phase analysis determined inter-joint coordination and variability for the knee-hip joint pair using Mean Absolute Relative Phase (MARP) and Deviation Phase (DP), respectively. One-way repeated measures ANOVAs tested surface effects. Post-hoc Bonferroni adjusted surface comparisons were assessed.

RESULTS

Significant knee-hip surface effects were seen during all gait phases for MARP (p < 0.001) and DP (p ≤ 0.001). Compared to flat walking, grass prompted more in-phase coordination (smaller MARP) during stance and swing phase (p ≤ 0.003). Slope-up caused more in-phase coordination during stance (p < 0.001), while slope-down caused more out-of-phase coordination during stance and swing (p ≤ 0.003), compared to the flat surface. Sloped surfaces prompted more variable (larger DP) knee-hip coordination (p ≤ 0.001), compared to flat walking during stance and swing phase.

SIGNIFICANCE

Compared to flat walking, changes in knee-hip coordination and variability were greatest on slope-up/slope-down surfaces. This could reflect greater changes in lower-limb kinematics on sloped surfaces and/or a neuromuscular response to the demands of a more challenging task.

951 More Than A Checkbox: Importance of Role-Modelling and Visibility Initiatives in Improving Perceptions of Diversity in Surgical Leadership

Introduction

The Royal College of Surgeons of England have committed themselves to championing diversity in surgery in light of recent socio-political events. Although there are now more trainees from underrepresented backgrounds entering the profession, this is not reflected in leadership roles which are key in establishing attitudes and cultures. This study evaluated whether an event showcasing surgeons from underrepresented groups holding leadership positions could improve student perceptions of diversity in surgical leadership.

Method

Participants attended an online event hosted by a student surgical society, where speakers with surgical leadership experience from a range of marginalised backgrounds highlighted topics of diversity and discrimination in surgery. Pre- and post-event questionnaires comprising Likert scales were completed to evaluate student perceptions of surgeons holding a leadership role from the following underrepresented groups: women (or gender non-conforming), BAME, LGBTQ+ and individuals with disabilities. Statistical significance was assessed using a Mann-Whitney U test with p &lt; 0.05 denoting significance throughout.

Results

The event significantly increased attendee confidence in the idea of a surgeon being seen in a leadership role from all underrepresented groups evaluated: 9.3% for female/gender non-conforming individuals (p &lt; 0.01), 12.3% for BAME individuals (p &lt; 0.01), 7.5% for non-heterosexual individuals (p = 0.04) and 16.0% for individuals with a disability (p &lt; 0.01).

Conclusions

Attendees felt significantly more confident in the belief that surgeons from underrepresented backgrounds could hold leadership positions following the event, indicating the benefit of such role-modelling initiatives. More investment is necessary in exploring factors dissuading specific underrepresented groups from pursuing surgical careers and for novel strategies to support these communities accordingly.

1526 Primary Hip and Knee Arthroplasty Documentation: Do Our Operation Notes Follow New GIRFT/BOA Guidelines? A Closed Loop Audit

Aim

Operation notes provide essential information about the techniques and implants used in surgery. Accurate documentation is important to improve patient outcomes and reduce rising litigation costs within the NHS. The aim of this audit was to assess compliance to recent guidance for hip and knee arthroplasty documentation, issued by the Getting It Right First Time (GIRFT) programme in 2019.

Method

Data was collected retrospectively from operation notes of all primary total/unicompartmental knee and hip arthroplasties during August 2019 and again in October 2019 at a DGH. Documentation was audited against data items from the GIRFT knee and hip arthroplasty ‘best practice’ guidelines. Interventions between timeframes included clinician education and a discussion of the guidelines between local surgeons.

Results

In audit rounds 1 and 2 twenty-six and 34 patients had THRs and 23 and 28 had knee arthroplasties respectively. 100% compliance was seen in 5/23 THR criteria and 9/27 knee criteria. Average compliance for knee documentation rose from 71% to 74% but no improvement was seen for THR (68% vs 64%). Those with least improvement related to assessment of range of movement and vascular status at the end of surgery.

Conclusions

Although compliance was good against the majority of data points there was minimal change following a local education intervention. The development and use of fully compliant departmental operation note templates would provide further clarity about steps performed and surgeon rationale should patient care later be scrutinised. The template would also act as an invaluable educational tool for trainees reflecting on the case.

Challenges in LTBI care in the United States identified using a nationwide TB medical consultation database

BACKGROUND

Identifying and treating individuals with latent TB infection (LTBI) represents a critical and challenging component of national TB elimination. Medical consultations by the Centers for Disease Control and Prevention (CDC) funded TB Centers of Excellence (COEs) are an important resource for healthcare professionals (HCPs) caring for individuals with LTBI. This study aimed to identify the most common clinical concerns regarding LTBI care and to describe epidemiologic and clinical features of patients discussed in these consultations.

METHODS

This mixed-methods study randomly sampled 125 consultation inquiries related to LTBI from the COEs' medical consultation database in 2018. Text from consultation records were reviewed and coded to identify reasons for the inquiries and common epidemiologic and clinical patient characteristics.

RESULTS

The most common topics of inquiry for consultation included accurate LTBI diagnosis (36%), management of LTBI treatment-related issues (22%), and choice of appropriate LTBI treatment regimen (17%). Patients for whom consultations were requested commonly had another medical condition (34%), were non-U.S. born (31%), were children (25%), and had a history of travel to TB-endemic areas (18%).

CONCLUSION

Our findings emphasize the challenge of managing patients with either suspected or confirmed LTBI, highlighting the need for ongoing medical consultation support for nuanced clinical and epidemiologic scenarios.

Prematurity and postnatal alterations in intermittent hypoxaemia

Intermittent hypoxaemia (IH) events are well described in extremely preterm infants, but the occurrence of IH patterns in more mature preterm infants remains unclear. The objective of this study was to characterise the effect of gestational age on early postnatal patterns of IH in extremely (<28 weeks), very (28-<32 weeks) and moderately (32-<34 weeks) preterm infants. As expected, extremely preterm infants had a significantly higher frequency of IH events of longer durations and greater time with hypoxaemia versus very and moderately preterm infants. In addition, the postnatal decrease in IH duration was comparable in the very and moderately preterm infants. This progression of IH events should assist clinicians and families in managing expectations for resolution of IH events during early postnatal life.

925 Is Routine Bloods Group and Save Required for Emergency Appendicectomy?

Introduction

Appendicectomy is commonly a safe and low bleeding risk procedure. However, some hospital guidelines stipulate a requirement for routine pre-operative blood group and save (G&S).We aim to determine if pre-operative G&S is required for appendicectomies by looking at the number of tests vs transfusion conducted.The cost of G&S is £4.14 per sample in our trust.

Method

A retrospective review was conducted over a 3-month period. Patient data and demographics were identified using the hospital coding, theatre records and transfusion departments.

Results

118 consecutive appendicectomies were identified. Of which, 99 laparoscopic vs 19 open (13 started open vs 6 converted to open) operations were performed. No patients required a blood transfusion during their admission. There was a total of 219 G&S conducted. Cross matching tests for these procedures cost a total of £906. We estimate a cost projection of £3624 for G&S tests over a year and £18120 over 3 years.

Conclusions

Bleeding complications requiring transfusion following appendicectomies are very uncommon. In our unit, 0% of patients identified required a transfusion during their admission. We suggest stopping routine pre-operative G&S for these patients would be clinically safe and would lead to financial savings and reduce pre-operative waiting time.

Surgical cardiac sympathetic denervation in patients with VT storm: long term follow-up data

Background

Surgical Cardiac Sympathetic Denervation (CSD) is a procedure which involves surgical removal of terminal cervical and thoracic sympathetic ganglion for reducing sympathetic discharge to the heart. CSD is usually performed as a last desperate measure in treatment of ventricular tachycardia (VT). We report here the clinical profile and long-term follow-up of all our patients who underwent CSD (unilateral or bilateral) predominantly upfront prior to considering catheter ablation of VT for VT storm.

Material and methods

We retrospectively collected data of all patients who underwent CSD for VT storm between year 2010 till 2019. Success of CSD was defined as successful discharge of patient from the hospital after the procedure more than 75% decrease in the frequency of VT after two weeks of surgical procedure.

Results

A total of 65 patients underwent CSD in the above-mentioned period and the average duration of follow-up was 28 months. The clinical parameters, demographic data and outcome analysis is provided in details in table 1. Only 14 (21.5%) patients underwent attempt of catheter ablation of VT prior to considering CSD. CSD was successful in 53 (81.5%) of patients. There was a significant decline in the incidence of number of ICD or external shocks before and after CSD (25.2±39.4 vs 1.09±2.9) respectively. There was no significant effect of CSD on ejection fraction. None of the available clinical parameters predicted the success of CSD.

Discussion and conclusion

The current retrospective analysis reemphasize the role of surgical CSD in treatment of patients with VT storm. As in predominant patient's CSD was performed even before the attempting catheter-based ablation, it brings in a new dimension in the treatment of VT. Efficacy of CSD (81.5%) in experienced hand is equivalent or even better than catheter-based ablation in patients with VT storm.

Funding Acknowledgement

Type of funding source: None

Tackling The Challenge Of Opioid Use And Abuse And Treatment Of Chronic Pain Management

Introduction/Objective

Deaths from opioid overdose increased 12% from 2016 to 2017. This major economic burden cost roughly $78.5 billion in the US. This steep increase in drug overdose deaths can be attributed to increased synthetic opioid abuse. To better understand and reduce opioid abuse amongst patients at Henry Ford Health System, Detroit MI, we sought to collaborate with physicians to manage prescribing, interpret test results, improve patient care, and deliver more value.

Primary Aim: To create a directed pain panel for ordering and interpreting pain management drugs to help providers to better manage patients and to assess compliance from test ordering history to serve patients safely and effectively.

Secondary Aim: To streamline the process of prescribing pain medications and to create a patient centered approach to treat chronic non-cancer patients who actually need opioids, to minimize the risk of abuse, diversion and addiction among patients.

Methods

Plan Do Check Act (PDCA) cycles of process improvement were used to achieve our two aims. In the first cycle, a drug screen-ordering guide was developed to facilitate screening (qualitative) and confirmation (quantitative) ordering practices. As part of this, providers prescribing for chronic pain patients were advised to use drugs of abuse panel rather than our emergency drug screen. In the second cycle, a directed pain panel (DPP) was introduced with reflex to confirmation testing. The DPP led to discovery of unexpected fentanyl positives, which were further investigated.

Results

A survey was conducted to investigate provider-ordering practices, which showed that use of the new drugs of abuse panel rose from 57% to 77%. The DPP was accepted by ~60% of physicians and was frequently reordered in follow-up. Analysis of unexpected fentanyl positivity revealed 30% true positivity, thus identifying unknown patient use. A future PDCA cycle is focused on developing, implementing, and measuring the customer value of a laboratory generated interpretive opioid results report at 5 similar organizations with a goal to assist with test selection and simplify provider interpretation of results.

Conclusion

A future PDCA cycle is focused on developing, implementing, and measuring the customer value of a laboratory generated interpretive opioid results report at 5 similar organizations with a goal to assist with test selection and simplify provider interpretation of results.

Intrathecal Access Through Suboccipital Port in Patients With Spinal Muscular Atrophy and Complex Spines: Case Series and Technical Note

Introduction

Many patients with the spinal muscular atrophy (SMA) have complex spinal anatomy, secondary to thoraco-lumbar spinal fusions. Their fragile musculoskeletal anatomy potentiates limb and joint injury if conventional spinal fluid access modalities are utilized. This creates a challenge when attempting to deliver intrathecal medications such as nusinersen (Spinraza®). Catheter placement in the cervical subarachnoid space with a caudally directed tip is potentially beneficial. This article describes our experience with Spinraza injections into the thecal space through a suboccipital port. This allowed for simple, chronic, and reliable cerebrospinal fluid (CSF) aspiration and intrathecal injections.

Methods

A total of 15 patients with SMA and complex spinal anatomy were implanted with a cervical subarachnoid catheter, connected to a suboccipital access port. We retrospectively reviewed the charts of these patients for clinical outcomes and complications. All patients then underwent serial port cannulation, aspiration of CSF, and injection of Spinraza following standard manufacturer dosage guidelines.

Results

The age range was 3 to 49. Two had type-1 SMA, 10 had type-2 SMA, and three had type-3 SMA. We were able to successfully cannulate the port, aspirate CSF, and inject Spinraza during all access attempts. Two incidents of subcutaneous CSF leaks were resolved through reoperation and one incident of transient CSF leak was resolved without surgical repair.

Conclusion

Patients with SMA requiring intrathecal injections of Spinraza can be treated safely and efficiently with this novel implantation technique. The complication rates are low and the injection time is dramatically lower than with conventional injection techniques.

0906 Identification Of Physical Exam Findings With High Predictive Value For Moderate To Severe Pediatric Obstructive Sleep Apnea(osa) In Overweight/obese Children

Introduction

Obstructive sleep apnea(OSA) is highly prevalent and under-diagnosed in the overweight/obese pediatric population largely due to limitations of existing pediatric OSA screening instruments including lack of efficiency and practical implementation and lack of careful consideration of physical examination(PE) findings with high predictive value for OSA. We sought to identify PE finding(s) predictive of pediatric OSA in overweight/obese patients to inform development of an OSA screening tool.

Methods

Overweight/obese patients presenting to the Cleveland Clinic weight-management clinic between 2013-2018 with polysomnogram (PSG) data were included. The association of PE predictors: age, sex, race (white, black, other), neck (NC), waist circumference (WC), tonsil size (TS), height, systolic and diastolic blood pressure (BP) percentiles) in relation to OSA defined by apnea-hypopnea index (AHI)≥5,i.e. clinically significant pediatric OSA, were assessed using univariate and multivariate logistic regression models (OR,95%CI).

Results

Retrospective analysis of 180 overweight/obese patients (BMI percentile&gt;85th for age and sex) and age 12.5±3.7 years were included. The multivariate model showed that only WC was significantly associated (1.03, 1.00 - 1.07, p=0.038) with OSA defined as AHI≥5. A statistically significant interaction of age and sex was observed such that the likelihood of OSA increased in males with older age and conversely decreased in females with older age. (1.26,1.04 -1.52, p=0.038) The reduced multivariate model, which included age, sex, WC, and age*sex interaction term, correctly discriminated AHI &lt;5 vs. ≥ 5 66.5% of the time.

Conclusion

In this large clinic-based overweight/obese pediatric sample, males, older age and WC were significant predictors of OSA and TS was not. A significant interaction of age and sex was observed supporting increased OSA with increasing age in males. Data generated supports value of PE findings of age, sex and WC to incorporate in development of an OSA screening tool for overweight/obese children.

Support

 

A Machine Learning Enabled Wireless Intracranial Brain Deformation Sensing System

A leading cause of traumatic brain injury (TBI) is intracranial brain deformation due to mechanical impact. This deformation is viscoelastic and differs from a traditional rigid transformation. In this paper, we describe a machine learning enabled wireless sensing system that predicts the trajectory of intracranial brain deformation. The sensing system consists of an implantable soft magnet and an external magnetic sensor array with a sensing volume of 12 × 12 × 4 mm³. Machine learning algorithm predicts the brain deformation by interpreting the magnetic sensor outputs created by the change in position of the implanted soft magnet. Three different machine learning models were trained on calibration data: (1) random forests, (2) k-nearest neighbors, and (3) a multi-layer perceptron-based neural network. These models were validated using both in vitro (a needle inserted into PVC gel) and in vivo (blast exposure to live and dead rat brains) experiments. The in vitro gel deformation predicted by these machine learning models showed excellent agreement with the camera measurements and had absolute error = 138 μm, Fréchet distance = 372 μm with normalized Procrustes disparity = 0.034. The in vivo brain deformation predicted by these models had absolute error = 50 μm, Fréchet distance = 95 μm with normalized Procrustes disparity = 0.055 for dead animal and absolute error = 125 μm, Fréchet distance = 289 μm with normalized Procrustes disparity = 0.2 for live animal respectively. These results suggest that the proposed machine learning enabled sensor system can be an effective tool for measuring in situ brain deformation.

Anthropogenic control over wintertime oxidation of atmospheric pollutants

During winter in the mid-latitudes, photochemical oxidation is significantly slower than in summer and the main radical oxidants driving formation of secondary pollutants, such as fine particulate matter and ozone, remain uncertain, owing to a lack of observations in this season. Using airborne observations, we quantify the contribution of various oxidants on a regional basis during winter, enabling improved chemical descriptions of wintertime air pollution transformations. We show that 25-60% of NO_x is converted to N₂O₅ via multiphase reactions between gas-phase nitrogen oxide reservoirs and aerosol particles, with ~93% reacting in the marine boundary layer to form >2.5 ppbv ClNO₂. This results in >70% of the oxidizing capacity of polluted air during winter being controlled, not by typical photochemical reactions, but from these multiphase reactions and emissions of volatile organic compounds, such as HCHO, highlighting the control local anthropogenic emissions have on the oxidizing capacity of the polluted wintertime atmosphere.

CT-Guided Block and Radiofrequency Ablation of the C2 Dorsal Root Ganglion for Cervicogenic Headache

The purpose of this report is to describe the technical aspects of CT-guided C2 dorsal root ganglion diagnostic block and radiofrequency ablation for refractory cervicogenic headache. CT guidance allows precise and safe positioning of a needle adjacent to the C2 dorsal root ganglion. At-risk neural and vascular structures can be avoided with CT, and it can provide a thorough understanding of upper cervical neuroanatomy.

Role of HAMP Genetic Variants on Pathophysiology of Iron Deficiency Anemia

Hepcidin is a 25-amino acid peptide hormone produced by hepatocytes and plays a key role in body iron metabolism. Hepcidin deficiency is the cause of iron overload in hereditary hemochromatosis, iron-loading anemia, and its excess is associated with anemia of inflammation, chronic disease and iron deficiency anemia (IDA). The aims of this study was to evaluate HAMP gene mutation, namely IVS2 + 1(-G) (c.148-150 + 1del) and Gly71 Asp (c.212G > A (rs104894696) association with iron status in IDA conditions. Our study participants were 500 IDA patients and 550 age and sex-matched healthy controls. Hepcidin, ferritin and CRP analysis was done by ELISA method while ESR analysis was done according to Wintrobe method. CBC analysis was done by auto-analyzer. Two mutations in the HAMP genes were analysed by PCR RFLP method. Among the IDA patients, 7 were heterozygous for Met50del IVS2 + 1(-G) mutation. Nine IDA patients were heterozygous for G71D G-A mutation and homozygous were not identified in both mutations.Controls were showing heterozygous frequency 1.8 and 2.1% of Met50del IVS2 + 1(-G) and G71D G-A mutations respectively. Mutation of HAMP (Met50del IVS2 + 1(-G) and G71D G-A) were clinically associated with IDA and act as modulator of disease.

Assessment of the inferior mesenteric vein diameter as a surrogate marker to evaluate response to neoadjuvant chemoradiotherapy for locally advanced rectal adenocarcinoma

AIM

Neoadjuvant chemoradiotherapy for locally advanced rectal cancer aims to downstage prior to definitive management. Repeat imaging assessment of the tumour post-therapy has implications for treatment. Our aim was to assess if the inferior mesenteric vein (IMV) diameter measured on CT can be used as a surrogate marker for evaluation of tumour response to neoadjuvant treatment.

METHOD

IMV diameter was assessed in patients with and without locally advanced rectal cancer, pre- and post-radiotherapy, to ascertain if IMV diameter is a surrogate marker of tumour response.

RESULTS

IMV diameter was 5.9 mm in patients with rectal cancer vs 4.7 mm in patients without (P = 0.0001). The baseline IMV diameter was significantly higher for cases with local lymphadenopathy [N0 5.2 mm vs N1/2 6 mm (P = 0.0059)] and extramural venous invasion (EMVI) [negative 5.4 mm vs positive 6.4 mm (P = 0.0001)]. Post-radiotherapy there was a significant decrease in the IMV diameter in cases with treatment response compared to non-responders: the percentage change in IMV diameter was a 17.54% decrease vs 1.39% increase (P = 0.0001). These results were reproduced on comparing between magnetic resonance tumour regression grades using ANOVA (P = 0.0001). There was also a significant decrease in IMV diameter when assessing lymph node (LN) and EMVI response vs non-responders (P = 0.0001 and 0.0001 respectively).

CONCLUSION

Patients with rectal cancer have a dilated IMV compared with patients without rectal cancer. We confirm that IMV diameter is a potential surrogate marker of LN status and EMVI at baseline. IMV diameter is also a marker of tumour, LN and EMVI response to chemoradiotherapy.

[18F]-Sodium Fluoride PET MR-Based Localization and Quantification of Bone Turnover as a Biomarker for Facet Joint-Induced Disability

Our aim was to prospectively evaluate the relationship between low back pain-related disability and quantitative measures from [¹⁸F]-sodium fluoride ([¹⁸F]-NaF) MR imaging. Six patients with facetogenic low back pain underwent dynamic [¹⁸F]-NaF PET/MR imaging. PET metrics were correlated with clinical measures and MR imaging grading of lumbar facet arthropathy. A significant positive correlation was observed between maximum facet joint uptake rate and clinical disability (P < .05). These data suggest that dynamic [¹⁸F]-NaF PET may serve as a useful biomarker for facetogenic disability.

Evaluation of pharmacokinetics of single-dose chloroquine in malnourished children with malaria- a comparative study with normally nourished children

OBJECTIVES

Studies on antimalarial kinetics in children or adults who are undernourished or malnourished are both limited and have yielded conflicting results. The present study was carried out with the objectives of evaluating the pharmacokinetics of single dose chloroquine and its metabolite desethylchloroquine in children who were undernourished and compare them with children who were normally nourished.

METHODS

Children of either gender between the ages of 5 and 12 years, smear positive for P. vivax malaria and classified either as well nourished or undernourished were included. Undernourishment was adjudged based on the Indian Academy of Pediatrics (IAP) classification of protein energy malnutrition [PEM] which in turn was based on Khadilkar's growth charts. All participants received 10 mg/kg on the first day followed by 10 mg/kg on Day 2 and 5 mg/kg on Day 3 along with supportive treatment. Blood samples for the levels of chloroquine [CQ] and desethylchloroquine [DECQ] were collected at 0, 0.5, 1, 2 4, 8, 12, 24, 48, 72 hours and 14 days after the first dose and levels assessed by High Performance Liquid Chromatography.

RESULTS

A total of 12 children who were normally nourished and 13 who were undernourished were studied. Wide inter-individual variability was seen in the levels of both drug and metabolite in both groups of patients. However, the differences in Cmax, AUC 0-inf, Clearance, half life and Vd between the two groups were not significantly different.

DISCUSSION

Our results indicate that dosage requirement is unlikely to be needed for chloroquine in undernourished children with uncomplicated P. vivax malaria.

Prediction of outcome in newly diagnosed myeloma: a meta-analysis of the molecular profiles of 1905 trial patients

Robust establishment of survival in multiple myeloma (MM) and its relationship to recurrent genetic aberrations is required as outcomes are variable despite apparent similar staging. We assayed copy number alterations (CNA) and translocations in 1036 patients from the NCRI Myeloma XI trial and linked these to overall survival (OS) and progression-free survival. Through a meta-anlysis of these data with data from MRC Myeloma IX trial, totalling 1905 newly diagnosed MM patients (NDMM), we confirm the association of t(4;14), t(14;16), t(14;20), del(17p) and gain(1q21) with poor prognosis with hazard ratios (HRs) for OS of 1.60 (P=4.77 × 10^-7), 1.74 (P=0.0005), 1.90 (P=0.0089), 2.10 (P=8.86 × 10^-14) and 1.68 (P=2.18 × 10^-14), respectively. Patients with 'double-hit' defined by co-occurrence of at least two adverse lesions have an especially poor prognosis with HRs for OS of 2.67 (P=8.13 × 10^-27) for all patients and 3.19 (P=1.23 × 10^-18) for intensively treated patients. Using comprehensive CNA and translocation profiling in Myeloma XI we also demonstrate a strong association between t(4;14) and BIRC2/BIRC3 deletion (P=8.7 × 10^-15), including homozygous deletion. Finally, we define distinct sub-groups of hyperdiploid MM, with either gain(1q21) and CCND2 overexpression (P<0.0001) or gain(11q25) and CCND1 overexpression (P<0.0001). Profiling multiple genetic lesions can identify MM patients likely to relapse early allowing stratification of treatment.