941 The Effect of COVID-19 on Orthopaedic Trauma Theatre Efficiency and Surgical Training in the North and East of Scotland Major Trauma Centres – a Year On

Aim

To determine the orthopaedic trauma theatre efficiency in two large major trauma centres (MTCs) in Scotland before and after the outbreak of Coronavirus disease (COVID-19) pandemic.

Method

All trauma patients presented to the North and East of Scotland's MTCs prior to the outbreak of COVID-19 (7th May to 7th June 2019), during the first peak of COVID-19 (7th May to 7th June 2020), after Aerosol Generating Procedures updates (7th November to 7th December 2020) and the ‘new normal’ (7th May to 7th June 2021) were retrospectively reviewed. Training opportunities and theatre time were compared. The Kruskall-Wallis test was used.

Results

There were no significant differences in the length of hospital stay (p=0.117, 0.065) and time from injuries and surgery within groups in both MTCs (p=0.508, 0.384). The pandemic has negatively affected the anaesthetic and surgical preparation time, time between end of procedure and send for next case, and turnover time, with more profound effect on the North of Scotland's MTC. The trainee's involvement as main surgeon had decreased with the outbreak of the pandemic, with the junior trainees being affected most severely in North of Scotland. The time taken for patient to arrive to theatre after sending and total downtime were twice as long in the North of Scotland.

Conclusion

The COVID-19 pandemic has negatively impacted the orthopaedic trauma theatre efficiency and training opportunities. Actions should be taken to improve the turnover time to maximise theatre efficiency while prioritizing training opportunities.

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC

DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6  ×  6  ×  6 m 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

Clinical metabolomics for inborn errors of metabolism

Metabolism is a highly regulated process that provides nutrients to cells and essential building blocks for the synthesis of protein, DNA and other macromolecules. In healthy biological systems, metabolism maintains a steady state in which the concentrations of metabolites are relatively constant yet are subject to metabolic demands and environmental stimuli. Rare genetic disorders, such as inborn errors of metabolism (IEM), cause defects in regulatory enzymes or proteins leading to metabolic pathway disruption and metabolite accumulation or deficiency. Traditionally, the laboratory diagnosis of IEMs has been limited to analytical methods that target specific metabolites such as amino acids and acyl carnitines. This approach is effective as a screening method for the most common IEM disorders but lacks the comprehensive coverage of metabolites that is necessary to identify rare disorders that present with nonspecific clinical symptoms. Fortunately, advancements in technology and data analytics has introduced a new field of study called metabolomics which has allowed scientists to perform comprehensive metabolite profiling of biological systems to provide insight into mechanism of action and gene function. Since metabolomics seeks to measure all small molecule metabolites in a biological specimen, it provides an innovative approach to evaluating disease in patients with rare genetic disorders. In this review we provide insight into the appropriate application of metabolomics in clinical settings. We discuss the advantages and limitations of the method and provide details related to the technology, data analytics and statistical modeling required for metabolomic profiling of patients with IEMs.

The Successful Implementation of Day Case Tonsillectomy

Objective Day case tonsillectomy is standard practice in many international centres, and is widespread across the UK. In Ireland, implementation has been slow for multiple reasons. Our unit aimed to introduce day case tonsillectomy, following a pilot programme. Following a year of implementation we have reaudited our practice. We hypothesised that day case tonsillectomy is a practical and favourable solution to facilitate access to surgery in the context of long waiting times for ENT surgery. Methods This was a prospective audit collecting data on day case tonsillectomy. All patients for day case tonsillectomy were selected in OPD according to our inclusion criteria. We recorded demographical data, surgical technique, length of stay, failed discharges, bleeding rate and readmission rate. Results There was one primary haemorrhage within 24 hours of surgery (0.08%). There were 16 secondary bleeds, giving a rate of 13.9%. Of these, four patients required a return to theatre for the cessation of bleeding (3.5%). There was no statistical significance in bleed rate between surgical technique. Failed discharge rate was 6%. The average time from extubation to discharge was 6 hours and 53 minutes. Conclusions Our experience of day case tonsillectomy is that it is safe, feasible and efficient in a selected group of patients. This can expedite long waiting times for tonsillectomy, and improve access to overnight beds for other cases. Our numbers represent the first unit in Ireland to have 2 year of experience with data showing successful implementation.

Floquet Solitons and Dynamics of Periodically Driven Matter Waves with Negative Effective Mass

We experimentally study the dynamics of weakly interacting Bose-Einstein condensates of cesium atoms in a 1D optical lattice with a periodic driving force. After a sudden start of the driving, we observe the formation of stable wave packets at the center of the first Brillouin zone (BZ) in momentum space, and we interpret these as Floquet solitons in periodically driven systems. The wave packets become unstable when we add a trapping potential along the lattice direction, leading to a redistribution of atoms within the BZ. The concept of a negative effective mass and the resulting changes to the interaction strength and effective trapping potential are used to explain the stability and the time evolution of the wave packets. We expect that similar states of matter waves exist for discrete breathers and other types of lattice solitons in periodically driven systems.

Poroid hidradenoma of the scalp in a US Veteran's Administration (VA) patient

Poroid hidradenomas are a rare subtype of hidradenoma. A Veteran’s Administration patient presented with a mobile, cystic scalp lesion. Intraoperatively the mass spontaneously ruptured. We hope clinicians will consider this entity on their differential when treating patients presenting with similar scalp lesions and intraoperative findings.

Global biochemical analysis of plasma, serum and whole blood collected using various anticoagulant additives

Introduction

Analysis of blood for the evaluation of clinically relevant biomarkers requires precise collection and sample handling by phlebotomists and laboratory staff. An important consideration for the clinical application of metabolomics are the different anticoagulants utilized for sample collection. Most studies that have characterized differences in metabolite levels in various blood collection tubes have focused on single analytes. We define analyte levels on a global metabolomics platform following blood sampling using five different, but commonly used, clinical laboratory blood collection tubes (i.e., plasma anticoagulated with either EDTA, lithium heparin or sodium citrate, along with no additive (serum), and EDTA anticoagulated whole blood).

Methods

Using an untargeted metabolomics platform we analyzed five sample types after all had been collected and stored at -80°C. The biochemical composition was determined and differences between the samples established using matched-pair t-tests.

Results

We identified 1,117 biochemicals across all samples and detected a mean of 1,036 in the sample groups. Compared to the levels of metabolites in EDTA plasma, the number of biochemicals present at statistically significant different levels (p<0.05) ranged from 452 (serum) to 917 (whole blood). Several metabolites linked to screening assays for rare diseases including acylcarnitines, bilirubin and heme metabolites, nucleosides, and redox balance metabolites varied significantly across the sample collection types.

Conclusions

Our study highlights the widespread effects and importance of using consistent additives for assessing small molecule levels in clinical metabolomics. The biochemistry that occurs during the blood collection process creates a reproducible signal that can identify specimens collected with different anticoagulants in metabolomic studies.

Impact statement

In this manuscript, normal/healthy donors had peripheral blood collected using multiple anticoagulants as well as serum during a fasted blood draw. Global metabolomics is a new technology being utilized to draw clinical conclusions and we interrogated the effects of different anticoagulants on the levels of biochemicals from each of the donors. Characterizing the effects of the anticoagulants on biochemical levels will help researchers leverage the information using global metabolomics in order to make conclusions regarding important disease biomarkers.

Assessment of the effects of repeated freeze thawing and extended bench top processing of plasma samples using untargeted metabolomics

INTRODUCTION

Clinical metabolomics has utility as a screen for inborn errors of metabolism (IEM) and variant classification in patients with rare disease. It is important to understand and characterize preanalytical factors that influence assay performance during patient sample testing.

OBJECTIVES

To evaluate the impact of extended thawing of human EDTA plasma samples on ice prior to extraction as well as repeated freeze-thaw cycling of samples to identify compounds that are unstable prior to metabolomic analysis.

METHODS

Twenty-four (24) donor EDTA plasma samples were collected and immediately frozen at - 80 °C. Twelve samples were thawed on ice and extracted for analysis at time 0, 2, 4, and 6 h. Twelve other donor samples were repeatedly thawed and frozen up to four times and analyzed at each cycle. Compound levels at each time point/freeze-thaw cycle were compared to the control samples using matched-paired t tests to identify analytes affected by each condition.

RESULTS

We identified 1026 biochemicals across all samples. Incubation of thawed EDTA plasma samples on ice for up to 6 h resulted in < 1% of biochemicals changing significantly. Freeze-thaw cycles affected a greater percentage of the metabolome; ~ 2% of biochemicals changed after 3 freeze-thaw cycles.

CONCLUSIONS

Our study highlights that the number and magnitude of these changes are not as widespread as other aspects of improper sample handling. In total, < 3% of the metabolome detected on our clinical metabolomics platform should be disqualified when multiple freeze-thaw cycles or extended thawing at 4 °C are performed on a given sample.

Processing light with an optically tunable mechanical memory

Mechanical systems are one of the promising platforms for classical and quantum information processing and are already widely-used in electronics and photonics. Cavity optomechanics offers many new possibilities for information processing using mechanical degrees of freedom; one of them is storing optical signals in long-lived mechanical vibrations by means of optomechanically induced transparency. However, the memory storage time is limited by intrinsic mechanical dissipation. More over, in-situ control and manipulation of the stored signals processing has not been demonstrated. Here, we address both of these limitations using a multi-mode cavity optomechanical memory. An additional optical field coupled to the memory modifies its dynamics through time-varying parametric feedback. We demonstrate that this can extend the memory decay time by an order of magnitude, decrease its effective mechanical dissipation rate by two orders of magnitude, and deterministically shift the phase of a stored field by over 2π. This further expands the information processing toolkit provided by cavity optomechanics.

Concordance between a neuroradiologist, a consultant radiologist and trained reporting radiographers interpreting MRI head examinations: An empirical study

INTRODUCTION

This study assessed agreement between MRI reporting radiographers and a consultant radiologist compared with an index neuroradiologist when reporting MRI head (brain/internal auditory meati [IAMs]) examinations. The effect on patient management of any discordant reports was also examined.

METHODS

Two trained MRI reporting radiographers (RRs), a consultant radiologist (CR) and an index neuroradiologist (INR) reported on a random sample of 210 MRI examinations. The radiographers reported during clinical practice and the radiologists in clinical practice conditions. Two independent consultant physicians (neuro-rehabilitation and neuropsychiatry) compared these reports with the index neuroradiologist report for agreement and the clinical importance of discrepant reports.

RESULTS

Overall observer agreement between the RRs and CR was comparable in relation to agreement with the INR: RR; 93/210 (44.3%); and the CR; 83/210 (39.4%) for all head MRI examinations (p = 0.32). For brain examinations the difference was similar: RR; 64/180 (35.6%); and CR; 54/190 (30.0%), p = 0.26. Agreement rates for the IAMs examinations were identical, 29/30 (97.7%). For all head MRI examinations (n = 210) there was a very small observed difference of <0.5% in mean agreement between the reporting radiographers and the consultant radiologist (p = 0.92) for examinations where a major disagreement would have been likely to have led to a change in patient management.

CONCLUSION

MRI reporting radiographers reported during clinical practice on MRI head examinations to a level of agreement comparable with a consultant radiologist.

IMPLICATIONS FOR PRACTICE

This is an area in which radiographers could provide additional reporting roles to the reporting service to increase capacity. Wider potential benefits include cost-effectiveness and role development/retention of radiographers.

Altered supraspinal motor networks in survivors of poliomyelitis: A cortico-muscular coherence study

OBJECTIVE

Poliomyelitis results in changes to the anterior horn cell. The full extent of cortical network changes in the motor physiology of polio survivors has not been established. Our aim was to investigate how focal degeneration of the lower motor neurons (LMN) in infancy/childhood affects motor network connectivity in adult survivors of polio.

METHODS

Surface electroencephalography (EEG) and electromyography (EMG) were recorded during an isometric pincer grip task in 25 patients and 11 healthy controls. Spectral signal analysis of cortico-muscular (EEG-EMG) coherence (CMC) was used to identify the cortical regions that are functionally synchronous and connected to the periphery during the pincer grip task.

RESULTS

A pattern of CMC was noted in polio survivors that was not present in healthy individuals. Significant CMC in low gamma frequency bands (30-47 Hz) was observed in frontal and parietal regions.

CONCLUSION

These findings imply a differential engagement of cortical networks in polio survivors that extends beyond the motor cortex and suggest a disease-related functional reorganisation of the cortical motor network.

SIGNIFICANCE

This research has implications for other similar LMN conditions, including spinal muscular atrophy (SMA). CMC has potential in future clinical trials as a biomarker of altered function in motor networks in post-polio syndrome, SMA, and other related conditions.

Collisionally Inhomogeneous Bose-Einstein Condensates with a Linear Interaction Gradient

We study the evolution of a collisionally inhomogeneous matter wave in a spatial gradient of the interaction strength. Starting with a Bose-Einstein condensate with weak repulsive interactions in quasi-one-dimensional geometry, we monitor the evolution of a matter wave that simultaneously extends into spatial regions with attractive and repulsive interactions. We observe the formation and the decay of solitonlike density peaks, counterpropagating self-interfering wave packets, and the creation of cascades of solitons. The matter-wave dynamics is well reproduced in numerical simulations based on the nonpolynomial Schrödinger equation with three-body loss, allowing us to better understand the underlying behavior based on a wavelet transformation. Our analysis provides new understanding of collapse processes for solitons, and opens interesting connections to other nonlinear instabilities.

Factors affecting medication assisted treatment success for opioid use disorder

Background

In the United States (US) when opioid use disorder (OUD) is treated with medication assisted treatment (MAT), many patients in MAT will relapse into active opioid use during the recovery process. About 23% drop out of treatment within 3 months, and 40-50% drop out within 6 months of MAT start. Using the Anderson and Newman (2005) Framework for Health Services Utilization, 27 variables reflecting predisposing, enabling, and need factors were used to examine the impact on the number of days patients were retained in treatment.

Methods

One MAT clinic in rural Michigan used random sample of archival records (n = 390) OUD patients (DSM-V-TR code 304.00, ICD-10 code F11.20) between Jan. 1, 2014 and Nov. 21, 2018 with prescribed buprenorphine as part of MAT program. The first set of linear regressions (backward elimination) defined significant variables for each factor, and the final model included significant variables to predict length of retention in MAT.

Results

The first step identified legal issues (predisposing), MSHN insurance, distance to clinic, ability to drive, mental health diagnosis, and homelessness (enabling factors); Zung self-reporting depression score, starting dose, past suicide attempt, Hep-C status, and method of use (needs factor) as statistically significant to be used in the final model, controlling for age and gender. Starting dose (unstandardized b = 136.8, 95%CI 98.0, 175.6), driving license (b = 68.3, CI 13.2, 123.4), distance to clinic (b=-1.1, CI -2.2, -0.5) had statistical impact on the length of stay in MAT.

Discussion

This case study identified enabling factors (starting dose and access to clinic) affecting length of participation in MAT. Other factors warranting provider attention were identified for rural OUD patients.

Conclusions

Evidence based guidelines for starting doses are needed to increase MAT effectiveness. MAT services should consider distance to clinic as a factor of successful treatment.

Key messages

Evidence based guidelines for starting doses are needed to increase MAT effectiveness. Opiood treatment services should consider distance to clinic as a factor of successful treatment.

0467 Benefits of CBT-I for Women Veterans with and without PTSD

Introduction

A quarter of women Veterans (WVs) receiving VA healthcare meet diagnostic criteria for both insomnia disorder and posttraumatic stress disorder (PTSD). Cognitive Behavioral Therapy for Insomnia (CBT-I) is effective at improving sleep among individuals with comorbid psychiatric conditions; however, no studies have examined the impact of CBT-I in women with insomnia plus PTSD. The current analyses examined changes in sleep symptoms, quality of life (QoL), and mental health symptoms from pre- to post-CBT-I in WVs with and without PTSD.

Methods

This was a secondary analysis of 75 WVs with insomnia (32 with probable PTSD), who received CBT-I within a behavioral sleep intervention study (NCT02076165). Measures completed at baseline, posttreatment, and 3-month follow-up included: insomnia severity (Insomnia Severity Index, ISI), sleep quality (Pittsburgh Sleep Quality Index, PSQI), PTSD symptoms (PTSD Checklist-5, PCL-5; probable PTSD=total score ≥33), depressive symptoms (Patient Health Qestionnaire-9, PHQ-9), and mental and physical quality of life (Short Form Health Survey, SF-12). One sample T-tests examined changes in ISI, PSQI, PHQ-9, PCL-5, and SF-12 from baseline to posttreatment and baseline to follow-up. Two samples T-tests compared change scores in ISI, PSQI, PHQ-9, and SF-12 between participants with and without PTSD.

Results

There were significant improvements in ISI (p≤.001), PSQI (p≤.001), PHQ-9 (p≤.001), PCL-5 (p=.001), and SF-12 mental (p≤.001) and physical (p=.03) from baseline to posttreatment and 3-month follow-up (p≤.001-.01). There were no significant change score differences between WVs with and without PTSD from baseline to posttreatment (p=.06-.98) or 3-month follow-up (p=.09-.93).

Conclusion

CBT-I appears to be an effective treatment to improve insomnia symptoms among WVs with and without PTSD, and may reduce psychiatric symptoms as well. These findings suggest WVs with comorbid insomnia and PTSD benefit from CBT-I. The appropriate sequencing of CBT-I and PTSD treatments remains potentially important, but unstudied.

Support

VA/HSR&D IIR-HX002300; NIH/NHLBI K24HL14305; VA Office of Academic Affiliations through the Advanced Fellowship Programs in HSR&D and Women’s Health