Reactogenicity, pregnancy outcomes, and SARS-CoV-2 infection following COVID-19 vaccination during pregnancy in Canada: A national prospective cohort study

OBJECTIVE

To describe self-reported reactogenicity, pregnancy outcomes, and SARS-CoV-2 infection following COVID-19 vaccination during pregnancy.

DESIGN

National, prospective cohort study.

SETTING

Participants across Canada were enrolled from July 2021 until June 2022.

POPULATION

Individuals pregnant during the COVID-19 pandemic, regardless of vaccination status, were included.

METHODS

The Canadian COVID-19 Vaccine Registry for Pregnant and Lactating Individuals (COVERED) was advertised through traditional and social media. Surveys were administered at baseline, following each vaccine dose if vaccinated, pregnancy conclusion, and every two months for 14 months. Changes to pregnancy or vaccination status, SARS-CoV-2 infections, or significant health events were recorded.

MAIN OUTCOME MEASURES

Reactogenicity (local and systemic adverse events, and serious adverse events) within 1 week post-vaccination, pregnancy and neonatal outcomes, and subsequent SARS-CoV-2 infection.

RESULTS

Among 2868 participants who received 1-2 doses of a COVID-19 vaccine during pregnancy, adverse events described included: headache (19.5-33.9%), nausea (4.8-13.8%), fever (2.7-10.2%), and myalgia (33.4-42.2%). Reactogenicity was highest after the 2nd dose of vaccine in pregnancy. Compared to 1660 unvaccinated participants, there were no statistically significant differences in adverse pregnancy or infant outcomes, aside from an increased risk of NICU admission ≥ 24 h among the unvaccinated group. During follow-up, there was a higher rate of participant-reported SARS-CoV-2 infection in the unvaccinated compared to the vaccinated group (18[47.4%] vs. 786[27.3%]).

CONCLUSIONS

Participant-reported reactogenicity was similar to reports from non-pregnant adults. There was no increase in adverse pregnancy and birth outcomes among vaccinated vs. unvaccinated participants and lower rates of SARS-CoV-2 infection were reported in vaccinated participants.

TWEETABLE ABSTRACT

No significant increase in adverse pregnancy or infant outcomes among vaccinated versus unvaccinated pregnant women in Canada.

Reasons for antiretroviral switching in Colombia: A retrospective cohort study

INTRODUCTION

Long-term use of antiretroviral therapy (ART) for HIV infection might lead to the necessity of switching regimens. We aimed to analyze the reasons for the ART switch, the time-to-switch of ART, and its associated factors in a Colombian cohort.

METHODS

We conducted a retrospective cohort in 20 HIV clinics, including participants ≥18 years old with confirmed HIV infection who underwent an ART switch from January 2017 to December 2019 with at least 6 months of follow-up. A time-to-event analysis and an exploratory Cox model were performed.

RESULTS

796 participants switched ART during the study period. The leading cause of ART switch was drug intolerance (n = 449; 56.4%) with a median time-to-switch of 12.2 months. The longest median time-to-switch was due to regimen simplification (42.4 months). People ≥50 years old (HR = 0.6; 95% CI (0.5-0.7) and CDC stage 3 at diagnosis (HR = 0.8; 95% CI (0.6-0.9) had less hazard for switching ART over time.

CONCLUSIONS

In this Colombian cohort, drug intolerance was the main cause of the ART switch, and the time-to-switch is shorter than reports from other countries. In Colombia, it is crucial to apply current recommendations for ART initiation to choose regimens with a better tolerability profile.

Motion Effects on Spatially Fractionated Lattice Therapy

PURPOSE/OBJECTIVE(S)

The practice of spatially fractionated radiation therapy (SFRT), such as grid and lattice, has been shown to be effective in managing large-size tumors for palliation or more recently for medium-sized tumors with definitive intents. The main feature that differentiates SFRT from standard radiation therapy is the deliberately high degree of dose heterogeneity in the gross tumor volume (GTV). The key parameter in assessing an SFRT plan is the valley-to-peak dose ratio (VPDR), which can be defined as a simple dose ratio between the low- and high-dose region in the tumor. The belief is that the healthy tissues in the low-dose regions of the tumor would serve as centers of tissue repair, while the high dose would kill the cancerous cells and induce the bystander effects. However, the compartments of low- and high-dose regions can be washed out due to motion, for example in cases when the disease is at or near the diaphragm. This work aims at examining motion effects on VPDR and equivalent uniform dose (EUD) in SFRT plans.

MATERIALS/METHODS

This work focuses on the effects of sinusoidal motion in lattice therapy, a 3D version of SFRT. A lattice VMAT plan with 6X was generated using the treatment planning system. Dose vertices were placed in a body-centered tetragonal lattice in a virtual water phantom. Each vertex was 1 cm3 and received 15 Gy to at least half of its volume. The volume ratio between the lattice and the GTV is about 3%. The distance between the two nearest vertice centers is 3 cm. A sinusoidal motion was introduced in the direction along the line connecting the two nearest neighbors and was binned into 10 phases with equal time intervals. The location of the phantom in each phase was determined by its average amplitude. The effect of the motion was assessed from the sum of all the plans in the 10 bins, each being scaled down by one-tenth of the prescribed dose. Dose coverage between the static and the sum plan is compared. Their difference in the VPDR and normal tissue damage with EUD are evaluated. The EUD was calculated based on Niemierko's formalism. The LQ model was used to estimate cell survival for normal tissues with a and b values of 0.366/Gy and 0.188 Gy2, respectively.

RESULTS

It is common to have the VPDR at around 1/3 or lower. Our study shows that it increases from 0.26 to 0.55 for the 1.5 cm motion and the EUD for normal tissue from 5 to 7 Gy. See Table 1 for more results. A large VPDR can reduce the ability of healthy tissues in the low-dose area for repair and a lower maximum dose in the vertices may diminish the bystander effects.

CONCLUSION

Motion may increase VPDR and normal tissue damage. Motion techniques such as gating or tracking can be used on disease sites subjected to respiratory motion.

Strangulated Gastric Hernia Following a Missed Traumatic Diaphragmatic Injury: A Case Report

Traumatic diaphragmatic injuries (TDIs) are rare and can be life-threatening, depending on the size of the injury and the contents herniating through it. They usually result from blunt or penetrating trauma to the thoracoabdominal area, with an incidence of 0.8-5% and up to 30% presenting late. A high index of suspicion should be maintained when evaluating patients with a history of trauma (severe blunt or thoracoabdominal penetrating trauma) and upper abdominal symptoms. We present a case of a missed TDI after a left posterior thoracoabdominal stab injury, which was evaluated with a diagnostic laparoscopy at an outside hospital. He presented to our emergency department (ED) with sudden onset left-sided chest pain and uncontrollable vomiting. A CT scan was obtained and showed a distended stomach herniating through a defect in the left hemidiaphragm. The patient was immediately taken for laparoscopic exploration and repair. There was a 5 cm defect in the left posterolateral diaphragm containing a strangulated stomach (approximately ⅔) and necrotic omentum. Complete reduction was achieved and the diaphragmatic defect was repaired primarily. His postoperative course was uncomplicated. This case illustrates the importance of maintaining a high index of suspicion for TDI, despite reports of previous exploration. Missed TDI can present with herniated intra-abdominal organs, which can become strangulated and increase morbidity and mortality.

A Novel Simulation Model for Training Emergency Medicine Residents in the Ultrasound Identification of Landmarks for Cricothyrotomy

Objectives The objective of this study is to describe a simple, replicable method to create neck models for the purpose of education and practice of ultrasound (US) identification of anatomic landmarks for cricothyrotomy. The second objective is to assess the model's capability in training emergency medicine (EM) residents in the US identification of anatomic landmarks for cricothyrotomy. Methods This is a cross-sectional study using a convenience sample of EM residents. Participants were taught to identify the thyroid cartilage, the cricothyroid membrane (CTM), and the cricoid cartilage using US. After an instructional period, participants performed a US examination on gel models designed to overly a live, human neck simulating various scenarios: thin neck, thick neck, anterior neck hematoma, and subcutaneous emphysema. Residents were asked to identify the thyroid cartilage, the CTM, and the cricoid cartilage as quickly as possible. The mean time to successful identification was reported in seconds. Following the scanning session, participants were asked to complete a post-survey. After the session, the video recordings were reviewed by an emergency US fellowship-trained physician to assess the visuomotor skills of each participant. Results A total of 42 residents participated in the study. Ninety-three percent (32/42; 95% CI 80.3% - 98.2%) of residents were able to obtain an optimal sagittal or parasagittal sonographic view of the anterior airway landmarks. Of these residents, 21.4% (9/42; 95% CI 11.5% - 36.2%) required minimal assistance with the initial probe placement. The visuomotor scores were recorded for each participant. Results of the pearson correlation indicated that there was a significant positive relationship between the residents' year in training with their visuomotor score (r(40) = .41, p = .007). When scanning the thin neck, 90.5% (38/42; 95% CI 77.4% - 96.8%) of residents were able to successfully identify the landmarks. The median time to completion was 27 seconds. When scanning the subcutaneous air model, 88.1% (37/42; 95% CI 74.5% - 95.3%) of residents were able to successfully identify the landmarks. The median time to completion was 26 seconds. When scanning the neck with the fluid collection 95.2% (40/42; 95% CI 83.4% - 99.5%) of residents were able to successfully identify the landmarks with a median time of 20 seconds for identification. When scanning the thick neck model, 73.8% (31/42; 95% CI 58.8% - 84.8%) of residents were able to successfully identify the landmarks taking a median time of 26 seconds. After the training session, 76.2% of residents reported that they felt either "confident" or "extremely confident" in identifying the CTM using US. Conclusion The novel anterior neck gel models used in this study were found to be adequate for training EM residents in the US identification of anterior neck anatomy. Residents were successfully trained in identifying the important anterior neck landmarks that are useful when predicting a difficult anterior airway and planning for surgical cricothyrotomy. Residents overall felt that the models simulated the appropriate anatomic scenarios. The majority felt confident in identifying the CTM using US.

Laparoscopic Janeway gastrostomy as preferred enteral access in specific patient populations: A systematic review and case series

BACKGROUND

Nutrition is one of the fundamental needs of both patient and non-patient populations. General trends promote enteral feeding as a superior route, with the most common enteral access being the percutaneous endoscopic gastrostomy (PEG) as the first-line procedure, with surgical access including Witzel gastrostomy, Stamm Gastrostomy, Janeway gastrostomy (JG) as secondary means.

AIM

To describe cases and technique of laparoscopic Janeway gastrostomy (LJG) and perform a systematic review of the data.

METHODS

We successfully performed two LJG procedures, after which we conducted a literature review of all documented cases of LJG from 1991 to 2022. We surveyed these cases to show the efficacy of LJG and provide comparisons to other existing procedures with primary outcomes of operative time, complications, duration of gastrostomy use, and application settings. The data were then extracted and assessed on the basis of the Reference Citation Analysis (https://www.referencecitationanalysis.com/).

RESULTS

We presented two cases of LJG, detailing the simplicity and benefits of this technique. We subsequently identified 26 articles and 56 cases of LJG and extrapolated the data relating to our outcome measures. We could show the potential of LJG as a viable and preferred option in certain patient populations requiring enteral access, drawing reference to its favorable outcome profile and low complication rate.

CONCLUSION

The LJG is a simple, reproducible procedure with a favorable complication profile. By its technical ease and benefits relating to the gastric tube formed, we propose this procedure as a viable, favorable enteral access in patients with the need for permanent or palliative gastrostomy, those with neurologic disease, agitation or at high risk of gastrostomy dislodgement, or where PEG may be infeasible.

Incidence of premature battery depletion in subcutaneous cardioverter-defibrillator patients. Insights from a multicenter registry

Funding Acknowledgements

Type of funding sources: None.

Introduction

A subset of more than 35,000 S-ICD is under FDA advisory, warning of the potential of premature battery depletion (PBD), caused by a faulty low-voltage capacitor. Based on internal data, the manufacturer projects the incidence at 3.7% after 5 years. Data independent from the manufacturer is sparse.

Methods

This study was a multicenter effort of 14 centers in Europe, the US, and Canada. Consecutive patients who received a S-ICD at the participating centers were included in this retrospective analysis. Patients with the 1010 S-ICD generator model, and those without available follow-up information were excluded. Data was collected and managed using REDCap electronic data capture tools hosted at the University Hospital Cologne.

The primary endpoint in this registry was device explantation, generator replacement, or generator failure. Reasons for explantation, replacement, or failure were collected. Device longevity was defined in months. It was calculated as the time from device insertion to the time of replacement, or explantation, or failure, where applicable. Premature battery depletion was defined as the occurrence of battery depletion requiring generator replacement after 60 months or less.

The study complies with the Declaration of Helsinki. Ethics committee approval was obtained. This study is registered with Clinicaltrials.gov.

Results

Data of n=1,102 S-ICD devices was analyzed. The registry comprised of S-ICD generators implanted between 03/2015 and 09/2021 (43.4% A209 model and 56.6% A219 model). Of these, 611 devices (55.4%) were identified by the Boston Scientific serial number lookup tool as affected by the advisory. The mean and median follow-up duration was 2.43±1.66 and 2.29 years, respectively.

During follow-up, 110 devices (10%) were explanted after 2.9±1.7 years. Battery depletion was the indication in 52. The endpoint of PBD (battery depletion after less than 5 years) was met in 37 devices (6% of the devices under advisory), after 4.1±0.6 years.

In 58 cases, the S-ICD was explanted for reasons other than battery depletion.

Infection (16), system upgrade (20), heart transplant or LVAD therapy (7), and inappropriate shocks or inappropriate sensing (7) were the most common indications.

Discussion

This registry provides a systematic and manufacturer independent analysis of premature battery depletion in S-ICD patients. In the affected devices, the incidence of premature battery occurred in 6%. This is higher than what is projected by the manufacturer. The rate of PBD increases notably around the 4-year mark.

Conclusion

S-ICD generators under advisory suffer from PBD at a higher incidence than previously reported. Patients equipped with these devices should be closely monitored.

Prevention and management of intra-operative pain during caesarean section under neuraxial anaesthesia: a technical and interpersonal approach

A woman who experiences pain during caesarean section under neuraxial anaesthesia is at risk of adverse psychological sequelae. Litigation arising from pain during caesarean section under neuraxial anaesthesia has replaced accidental awareness under general anaesthesia as the most common successful medicolegal claim against obstetric anaesthetists. Generic guidelines on caesarean section exist, but they do not provide specific recommendations for this area of anaesthetic practice. This guidance aims to offer pragmatic advice to support anaesthetists in caring for women during caesarean section. It emphasises the importance of non-technical skills, offers advice on best practice and aims to encourage standardisation. The guidance results from a collaborative effort by anaesthetists, psychologists and patients and has been developed to support clinicians and promote standardisation of practice in this area.

Magnetic resonance imaging in the evaluation of idiopathic frequent premature ventricular complexes with normal ventricular function

Background

The role of cardiac magnetic resonance (CMR) imaging in the diagnostic evaluation of patients with frequent premature ventricular complexes (PVCs) and normal left ventricular ejection fraction (LVEF) remains unclear. Existing data has been predominantly derived from highly selected populations, that may overestimate the true prevalence of abnormal findings on CMR in this patient population.

Purpose

The aim of this study was 2-fold: 1) to establish the prevalence of CMR imaging abnormalities in a cohort with normal LVEF and high PVC burden; 2) to identify predictors of CMR imaging abnormalities in patients with frequent PVCs and normal LVEF.

Methods

In this cohort study, 211 patients (age 53.2±19 years; 41% male) with frequent PVCs (≥5%/24 h), of normal LVEF (≥50% by echocardiography) and no known underlying structural heart disease were prospectively enrolled from 2016–2020. Of these, 166 (79%) patients were symptomatic from their PVCs in the form of palpitations, fatigue, chest pain, dizziness, and/or dyspnea. Patients underwent CMR imaging (1.5 Tesla) with a late gadolinium enhancement (LGE) protocol at the time of enrollment for the detection of scarring and/or fibrosis.

Results

Patients had a median baseline echocardiographic LVEF of 60% (± 5%) with 195 (92%) of patients having a normal native QRS morphology. Median PVC burden of the study cohort was 16% (± 14%). CMR LGE abnormalities were found in 19 (9%) patients including 17 scans with non-ischemic LGE and 2 with ischemic LGE. Age >60 (odds ratio [OR]: 3.20, 95% confidence interval [CI]: 1.20–8.51, p=0.020), male sex (OR: 4.67, 95% CI: 1.61–13.50, p=0.004), history of hypertension (OR: 3.43, 95% CI: 1.31–8.97, p=0.012), native QRS duration (OR: 1.03, 95% CI: 1.00–1.05, p=0.031), and history of non-sustained ventricular tachycardia (OR: 2.81, 95% CI: 1.03–7.68, p=0.044) were significantly associated with the presence of imaging abnormalities on CMR. Dominant PVC origin from the left ventricle had a positive trend (OR: 2.60, 95% CI: 0.99–7.66, p=0.083) to association with CMR imaging abnormalities. On multivariate analysis, male sex (OR: 4.10, 95% CI: 1.40–12.04, p=0.010) and history of hypertension (OR: 2.89, 95% CI: 1.08–7.75, p=0.035) remained significantly associated with the presence of CMR abnormalities. There was no association between CMR imaging abnormalities and the burden of PVCs or the number of PVC morphologies.

Conclusion

In this cohort, only 9% of patients with apparently idiopathic frequent PVCs and normal LVEF had concealed myocardial abnormalities on CMR imaging. Male sex and history of hypertension were associated with a higher rate of CMR abnormalities.

Funding Acknowledgement

Type of funding sources: None.

Consolidation nivolumab and ipilimumab versus observation in limited-disease small-cell lung cancer after chemo-radiotherapy - results from the randomised phase II ETOP/IFCT 4-12 STIMULI trial

BACKGROUND

Concurrent chemotherapy and thoracic radiotherapy followed by prophylactic cranial irradiation (PCI) is the standard treatment in limited-disease small-cell lung cancer (LD-SCLC), with 5-year overall survival (OS) of only 25% to 33%.

PATIENTS AND METHODS

STIMULI is a 1:1 randomised phase II trial aiming to demonstrate superiority of consolidation combination immunotherapy versus observation after chemo-radiotherapy plus PCI (protocol amendment-1). Consolidation immunotherapy consisted of four cycles of nivolumab [1 mg/kg, every three weeks (Q3W)] plus ipilimumab (3 mg/kg, Q3W), followed by nivolumab monotherapy (240 mg, Q2W) for up to 12 months. Patient recruitment closed prematurely due to slow accrual and the statistical analyses plan was updated to address progression-free survival (PFS) as the only primary endpoint.

RESULTS

Of the 222 patients enrolled, 153 were randomised (78: experimental; 75: observation). Among the randomised patients, median age was 62 years, 60% males, 34%/65% current/former smokers, 31%/66% performance status (PS) 0/1. Up to 25 May 2020 (median follow-up 22.4 months), 40 PFS events were observed in the experimental arm, with median PFS 10.7 months [95% confidence interval (CI) 7.0-not estimable (NE)] versus 42 events and median 14.5 months (8.2-NE) in the observation, hazard ratio (HR) = 1.02 (0.66-1.58), two-sided P = 0.93. With updated follow-up (03 June 2021; median: 35 months), median OS was not reached in the experimental arm, while it was 32.1 months (26.1-NE) in observation, with HR = 0.95 (0.59-1.52), P = 0.82. In the experimental arm, median time-to-treatment-discontinuation was only 1.7 months. CTCAE v4 grade ≥3 adverse events were experienced by 62% of patients in the experimental and 25% in the observation arm, with 4 and 1 fatal, respectively.

CONCLUSIONS

The STIMULI trial did not meet its primary endpoint of improving PFS with nivolumab-ipilimumab consolidation after chemo-radiotherapy in LD-SCLC. A short period on active treatment related to toxicity and treatment discontinuation likely affected the efficacy results.

Whipping properties of recombined, additive-free creams

There is increasing industrial interest in the use of the milkfat globule membrane as a food ingredient. The objective of this research was to determine whether the aerosol whipping performance of cream separated into butter and buttermilk, and then recombined, would perform in a manner similar to untreated cream. Churning of cream tempered to different solid fat contents was used to separate butter from buttermilk, which were then recombined at the same ratios as the initial extraction yield, or with 25% extra buttermilk. Differences in milkfat globule size distributions among the recombined creams were apparent; however, their whipping behavior and overrun were similar. Importantly, all recombined creams did not yield properties similar to the original cream, indicating that the unique native milkfat globule membrane structure plays a role in cream performance well beyond its simple presence.

Incidence of accidental awareness during general anaesthesia in obstetrics: a multicentre, prospective cohort study

General anaesthesia for obstetric surgery has distinct characteristics that may contribute towards a higher risk of accidental awareness during general anaesthesia. The primary aim of this study was to investigate the incidence, experience and psychological implications of unintended conscious awareness during general anaesthesia in obstetric patients. From May 2017 to August 2018, 3115 consenting patients receiving general anaesthesia for obstetric surgery in 72 hospitals in England were recruited to the study. Patients received three repetitions of standardised questioning over 30 days, with responses indicating memories during general anaesthesia that were verified using interviews and record interrogation. A total of 12 patients had certain/probable or possible awareness, an incidence of 1 in 256 (95%CI 149-500) for all obstetric surgery. The incidence was 1 in 212 (95%CI 122-417) for caesarean section surgery. Distressing experiences were reported by seven (58.3%) patients, paralysis by five (41.7%) and paralysis with pain by two (16.7%). Accidental awareness occurred during induction and emergence in nine (75%) of the patients who reported awareness. Factors associated with accidental awareness during general anaesthesia were: high BMI (25-30 kg.m^-2 ); low BMI (<18.5 kg.m^-2 ); out-of-hours surgery; and use of ketamine or thiopental for induction. Standardised psychological impact scores at 30 days were significantly higher in awareness patients (median (IQR [range]) 15 (2.7-52.0 [2-56]) than in patients without awareness 3 (1-9 [0-64]), p = 0.010. Four patients had a provisional diagnosis of post-traumatic stress disorder. We conclude that direct postoperative questioning reveals high rates of accidental awareness during general anaesthesia for obstetric surgery, which has implications for anaesthetic practice, consent and follow-up.

Balance Right in Multiple Sclerosis (BRiMS): a feasibility randomised controlled trial of a falls prevention programme

Background

Balance, mobility impairments and falls are problematic for people with multiple sclerosis (MS). The “Balance Right in MS (BRiMS)” intervention, a 13-week home and group-based exercise and education programme, aims to improve balance and minimise falls. This study aimed to evaluate the feasibility of undertaking a multi-centre randomised controlled trial and to collect the necessary data to design a definitive trial.

Methods

This randomised controlled feasibility study recruited from four United Kingdom NHS clinical neurology services. Patients ≥ 18 years with secondary progressive MS (Expanded Disability Status Scale 4 to 7) reporting more than two falls in the preceding 6 months were recruited. Participants were block-randomised to either a manualised 13-week education and exercise programme (BRiMS) plus usual care, or usual care alone.

Feasibility assessment evaluated recruitment and retention rates, adherence to group assignment and data completeness. Proposed outcomes for the definitive trial (including impact of MS, mobility, quality of life and falls) and economic data were collected at baseline, 13 and 27 weeks, and participants completed daily paper falls diaries.

Results

Fifty-six participants (mean age 59.7 years, 66% female, median EDSS 6.0) were recruited in 5 months; 30 randomised to the intervention group. Ten (18%) participants withdrew, 7 from the intervention group. Two additional participants were lost to follow up at the final assessment point. Completion rates were > 98% for all outcomes apart from the falls diary (return rate 62%).

After adjusting for baseline score, mean intervention—usual care between-group differences for the potential primary outcomes at week 27 were MS Walking Scale-12v2: − 7.7 (95% confidence interval [CI] − 17.2 to 1.8) and MS Impact Scale-29v2: physical 0.6 (CI − 7.8 to 9), psychological − 0.4 (CI − 9.9 to 9). In total, 715 falls were reported, rate ratio (intervention:usual care) for falls 0.81 (0.41 to 2.26) and injurious falls 0.44 (0.41 to 2.23).

Conclusions

Procedures were practical, and retention, programme engagement and outcome completion rates satisfied a priori progression criteria. Challenges were experienced in completion and return of daily falls diaries. Refinement of methods for reporting falls is therefore required, but we consider a full trial to be feasible.

Trial registration

ISRCTN13587999

Date of registration: 29 September 2016

Machine learning for predicting AF ablation outcomes using daily heart rhythm data at baseline

Background

While numerous studies have shown that catheter ablation is superior to antiarrhythmic drug (AAD) in treating atrial fibrillation (AF), the long term outcomes have been limited by arrhythmia recurrence. Reliable data and methods to predict ablation outcomes will thus be valuable for treatment planning.

Objective

To evaluate the utility of machine learning and various types of input variables, viz. patient characteristics at baseline, and daily heart rhythm data recorded prior to ablation for outcome prediction.

Methods

We acquired permission to analyze data collected from a randomized clinical trial that recorded daily biomeasures from &gt;345 patients who were referred for first catheter ablation due to AF refractory to at least one AAD. After standardizing the dataset, each patient sample is characterized by a set of daily measures, viz. heart rate variability (HRV) and AF burden (AFB), which is the total minutes in AF per day. We next performed comparative analyses on 19 candidate model variants to evaluate each model's ability in identifying patients who were to experience at least one episode of AF recurrence during post-ablation period starting from day 91 up to day 365 post-ablation, per standard guidelines. We examined: i) use of a set of daily biomeasures jointly with baseline sex and age; and ii) observation lengths of the pre-ablation period. We also examined the use of baseline CHA2DS2-VASc scores, left-atrial volume (LAV), atrial diameter, medical history. We conducted multiple sets of 3-fold cross validation (CV) experiments, each fold independently trained a candidate model with 236 samples (two thirds of the dataset) and performed evaluation on the left-out samples. About 50% of cohort belongs to one class. Each fold scored a model and its input variables in terms of sensitivity (SEN), specificity (SPEC), area under receiver operating characteristic curve (AUC), etc. To circumvent risks of overfitting highly parameterized models to our training subset, we shortlisted 19 models that have few hyper-parameters, e.g. stepwise regression, random forest (RF), linear discriminant analysis (LDA).

Results

CV results demonstrated that LDA and RF gave comparable performances, with RF achieving highest AUC of 0.68±0.06 using 30 days of rhythm data prior to ablation (SEN of 65.9±7.82; SPEC of 66.3±0.57). When observation period extended to 90 days prior, AUC improved to 0.691±0.02. In contrast, use of LAV alone was not adequate to predict outcome (AUC∼0.5), and when combined with all aforementioned baseline variables, the best model achieved AUC of 0.58±0.05. Feature analyses from the trained models suggest that AFB had highest relevance in predicting outcome. Using only daily AFB, RF and LDA respectively achieved AUC of 0.608±0.04 and 0.652±0.04.

Conclusions

Our results suggest the value of pre-ablation rhythm data for improving outcome-prediction. Future work will validate these findings using large public datasets.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Huawei-Data Science Institute Research Program; Natural Sciences and Engineering Research Council of Canada (NSERC)

General anaesthetic and airway management practice for obstetric surgery in England: a prospective, multicentre observational study

There are no current descriptions of general anaesthesia characteristics for obstetric surgery, despite recent changes to patient baseline characteristics and airway management guidelines. This analysis of data from the direct reporting of awareness in maternity patients' (DREAMY) study of accidental awareness during obstetric anaesthesia aimed to describe practice for obstetric general anaesthesia in England and compare with earlier surveys and best-practice recommendations. Consenting patients who received general anaesthesia for obstetric surgery in 72 hospitals from May 2017 to August 2018 were included. Baseline characteristics, airway management, anaesthetic techniques and major complications were collected. Descriptive analysis, binary logistic regression modelling and comparisons with earlier data were conducted. Data were collected from 3117 procedures, including 2554 (81.9%) caesarean deliveries. Thiopental was the induction drug in 1649 (52.9%) patients, compared with propofol in 1419 (45.5%). Suxamethonium was the neuromuscular blocking drug for tracheal intubation in 2631 (86.1%), compared with rocuronium in 367 (11.8%). Difficult tracheal intubation was reported in 1 in 19 (95%CI 1 in 16-22) and failed intubation in 1 in 312 (95%CI 1 in 169-667). Obese patients were over-represented compared with national baselines and associated with difficult, but not failed intubation. There was more evidence of change in practice for induction drugs (increased use of propofol) than neuromuscular blocking drugs (suxamethonium remains the most popular). There was evidence of improvement in practice, with increased monitoring and reversal of neuromuscular blockade (although this remains suboptimal). Despite a high risk of difficult intubation in this population, videolaryngoscopy was rarely used (1.9%).

164 Gonadotrophin-releasing hormone injection and colour flow Doppler ultrasound of the preovulatory follicle as a tool to increase pregnancy outcome after timed AI in beef cows

The aims of this study were to determine (1) the association between Doppler vascularisation scores (DVS) of the preovulatory follicle (POF) and fertility of beef cows submitted to timed AI (TAI) and (2) whether cows with low DVS benefit from a gonadotrophin-releasing hormone (GnRH) treatment at TAI. Multiparous lactating Nelore cows (Bos indicus; n=69) from a commercial beef farm in the state of Rondônia, Brazil, were enrolled in this study. Cows received 2mg of oestradiol benzoate intramuscularly (Bioestrogen, Biogénesis Bagó) and an intravaginal progesterone-releasing device (1.9g of progesterone; controlled internal drug release, CIDR) to synchronise follicular wave emergence on Day 0. The CIDR device was removed and cows were treated with 150μg of D-cloprostenol intramuscularly (prostaglandin F2α analogue; Croniben), 1mg of oestradiol cypionate intramuscularly, and 300IU of equine chorionic gonadotrophin (Novormon) intramuscularly on Day 8. Cows were then painted with a tail chalk marker to identify those displaying oestrus. All cows were submitted to TAI 48h after CIDR removal. At TAI, occurrence of oestrus was recorded and all cows were examined using transrectal ultrasonography. Blood flow of the POF was evaluated using colour Doppler imaging. Colour Doppler signals present on the follicular wall were subjectively scored using a 1-to-4 scale (1=absence or very low blood flow, and 4=intense blood flow detected on most of the follicular wall surface) adapted from Ginther (2007Ultrasonic Imaging and Animal Reproduction: Color-Doppler Ultrasonography, pages 87-114). Then, cows were divided into three groups according their DVS of the POF: (1) high DVS (DVS ≥3; n=36), (2) low DVS (DVS &lt;3; n=16), and (3) low DVS (DVS &lt;3; n=17) plus a GnRH treatment at TAI. The diameter of the POF was analysed using analysis of variance (PROC GLIMMIX of SAS; SAS Institute Inc.), and the means were compared among groups using Tukey's test. The proportion of cows that displayed oestrus and pregnancy rates was analysed using chi-square test. Cows in the high-DVS group had a larger POF than cows in the low-DVS and low-DVS-GnRH groups (13.2±0.2, 11.7±0.5, and 12.2±0.4, respectively; P&lt;0.05). The proportion of cows that displayed oestrus was greater (P&lt;0.05) in the high-DVS group (72%, 26/36) than in the low-DVS (37.5%, 6/16) or low-DVS-GnRH (53%, 9/17) groups. Finally, greater (P&lt;0.05) pregnancy rates were observed in cows from the high-DVS (47.2%; 17/36) and low-DVS-GnRH (52.9%; 9/17) groups than in cows from the low-DVS group (18.7%; 3/16). The preliminary results from this study demonstrated that diameter of POF is positively associated with DVS. Moreover, cows that presented POF with higher DVS are more likely to become pregnant, and the administration of GnRH to females with low DVS can increase the fertility of beef cows submitted to TAI protocols. This study received funding support from Embrapa (MP1/PC3 project no. 01.03.14.011.00.00) and from CNPq (universal project no. 407307/2016-8).

P6536Implementation of a mass atrial fibrillation screening program in Canadian community practice

Background

Atrial fibrillation is the most common arrhythmia seen in clinical practice, and is an important cause of stroke. In up to 10% of patients, stroke is the first clinical manifestation of undiagnosed atrial fibrillation (AF). Early detection of AF is therefore desirable, as it would provide an opportunity to initiate appropriate stroke prevention with anticoagulation. While European guidelines recommend screening for AF as part of routine care in patients with risk factors, the optimal modality has not yet been determined. Smartphone enabled single lead ECG devices have been shown to be highly accurate and could prove to be an effective point of care tool for uncovering AF in the community and may facilitate implementation of screening recommendations.

Purpose

We sought to describe the integration of a smartphone enabled single lead ECG device into the practice of selected Canadian community-based physicians and its impact on patient care.

Methods

Canadian community-based physicians were provided with a smartphone enabled single lead ECG device for a period of six months. Physicians were instructed to perform a single 30 second ECG recording in patients over the age of 65 who present for a regular follow-up visit. Patients with previous AF diagnosis were excluded. Outcomes related to screening, and stroke prevention-treatment initiation were prospectively ascertained and documented using a patient flow tracker.

Results

Among 612 physicians who were invited to participate in the program, 315 (51%) agreed to track and report the use of the device that was provided to them. During this program, 315 physicians screened a total of 15,538 patients. AF was detected 1103 patients (7.1%). The majority of patients with a positive screen underwent a subsequent 12-lead ECG confirmatory exam (79%). AF could not be confirmed in 277 patients (31.7% of patients undergoing 12-lead ECG). A total of 677 patients were initiated on oral anticoagulation (OAC), with 262 patients (24%) being initiated on OAC prior to ECG confirmation.

Conclusion

Undiagnosed AF is common in patients >65 years of age in community practice. The results of this program indicate that single lead mobile ECG devices can be integrated into routine point of care use for Canadian physicians and, can be a valuable tool to detect previously undiagnosed AF. While this approach identified a large number of undiagnosed AF patients eligible for OAC therapy, undertreatment with OAC remains a concern.

Acknowledgement/Funding

Bristol-Myers Squibb/Pfizer Alliance

Deubiquitinase USP10 regulates Notch signaling in the endothelium

Notch signaling is a core patterning module for vascular morphogenesis that codetermines the sprouting behavior of endothelial cells (ECs). Tight quantitative and temporal control of Notch activity is essential for vascular development, yet the details of Notch regulation in ECs are incompletely understood. We found that ubiquitin-specific peptidase 10 (USP10) interacted with the NOTCH1 intracellular domain (NICD1) to slow the ubiquitin-dependent turnover of this short-lived form of the activated NOTCH1 receptor. Accordingly, inactivation of USP10 reduced NICD1 abundance and stability and diminished Notch-induced target gene expression in ECs. In mice, the loss of endothelial Usp10 increased vessel sprouting and partially restored the patterning defects caused by ectopic expression of NICD1. Thus, USP10 functions as an NICD1 deubiquitinase that fine-tunes endothelial Notch responses during angiogenic sprouting.

Avascular necrosis in children with cerebral palsy after reconstructive hip surgery

PURPOSE

Progressive hip displacement is one of the most common orthopaedic pathologies in children with cerebral palsy (CP). Reconstructive hip surgery has become the standard treatment of care. Reported avascular necrosis (AVN) rates for hip reconstructive surgery in these patients vary widely in the literature. The purpose of this study is to identify the frequency and associated risk factors of AVN for reconstructive hip procedures.

METHODS

A retrospective analysis was performed of 70 cases of reconstructive hip surgery in 47 children with CP, between 2009 and 2013. All 70 cases involved varus derotation osteotomy (VDRO), with 60% having combined VDRO and pelvic osteotomies (PO), and 21% requiring open reductions. Mean age at time of surgery was 8.82 years and 90% of patients were Gross Motor Function Classification System (GMFCS) 4 and 5. Radiographic dysplasia parameters were analysed at selected intervals, to a minimum of one year post-operatively. Severity of AVN was classified by Kruczynski's method. Bivar- iate statistical analysis was conducted using Chi-square test and Student's t-test.

RESULTS

There were 19 (27%) noted cases of AVN, all radio- graphically identifiable within the first post-operative year. The majority of AVN cases (63%) were mild to moderate in severity. Pre-operative migration percentage (MP) (p = 0.0009) and post-operative change in MP (p = 0.002) were the most significant predictors of AVN. Other risk factors were: GMFCS level (p = 0.031), post-operative change in NSA (p = 0.02) and concomitant adductor tenotomy (0.028).

CONCLUSION

AVN was observed in 27% of patients. Severity of displacement correlates directly with AVN risk and we suggest that hip reconstruction, specifically VDRO, be performed early in the 'hip at risk' group to avoid this complication.

Balance Right in Multiple Sclerosis (BRiMS): a guided self-management programme to reduce falls and improve quality of life, balance and mobility in people with secondary progressive multiple sclerosis: a protocol for a feasibility randomised controlled trial

BACKGROUND

Impaired mobility is a cardinal feature of multiple sclerosis (MS) and is rated by people with MS as their highest priority. By the secondary progressive phase, balance, mobility and physical activity levels are significantly compromised; an estimated 70% of people with secondary progressive MS fall regularly. Our ongoing research has systematically developed 'Balance Right in MS' (BRiMS), an innovative, manualised 13-week guided self-management programme tailored to the needs of people with MS, designed to improve safe mobility and minimise falls. Our eventual aim is to assess the clinical and cost effectiveness of BRiMS in people with secondary progressive MS by undertaking an appropriately statistically powered, multi-centre, assessor-blinded definitive, randomised controlled trial. This feasibility study will assess the acceptability of the intervention and test the achievability of running such a definitive trial.

METHODS/DESIGN

This is a pragmatic multi-centre feasibility randomised controlled trial with blinded outcome assessment. Sixty ambulant people with secondary progressive MS who self-report two or more falls in the previous 6 months will be randomly allocated (1:1) to either the BRiMS programme plus usual care or to usual care alone. All participants will be assessed at baseline and followed up at 15 weeks and 27 weeks post-randomisation. The outcomes of this feasibility trial include:Feasibility outcomes, including trial recruitment, retention and completionAssessment of the proposed outcome measures for the anticipated definitive trial (including measures of walking, quality of life, falls, balance and activity level)Measures of adherence to the BRiMS programmeData to inform the economic evaluation in a future trialProcess evaluation (assessment of treatment fidelity and qualitative evaluation of participant and treating therapist experience).

DISCUSSION

The BRiMS intervention aims to address a key concern for MS service users and providers. However, there are several uncertainties which need to be addressed prior to progressing to a full-scale trial, including acceptability of the BRiMS intervention and practicality of the trial procedures. This feasibility trial will provide important insights to resolve these uncertainties and will enable a protocol to be finalised for use in the definitive trial.

TRIAL REGISTRATION

ISRCTN13587999.

Neuroleptic-induced Parkinsonism in Patient with Obsessive Compulsive Disorder: A Case Report

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder characterized by either obsessions (recurrent unwanted thoughts, images or impulses) or compulsions (repetitive behaviors often performed to relieve anxiety or distress). In some cases, it is considered antipsychotic enhancement. However, in high doses, it can exacerbate OCD symptoms and cause extrapyramidal effects such as neuroleptic-induced Parkinsonism.

Here, the authors present a clinic case of a single male patient with 50 years old, in which with the age of 42, started with a obsessive-compulsive framework about the developed task at the work place (production of fabric) followed by several verifications of the assembled pieces, which interfered with his work performance. This patient was admitted to the psychiatric hospital due to the deterioration of the symptoms with obsessive ideas of HIV contamination resulting in rigid cleaning rituals. He was medicated with several OCD medications including Clozapine 50 mg.

In the following years and complaining of insomnia, the clozapine dose was increased by the patient reaching the dose of 200 mg. In 2016 he started secondary Parkinsonism framework to antipsychotics, characterized by akinesia, facial hypomimia, stiff, coarse tremor and stooped posture. Therapeutic setting was made with a reduction of clozapine at doses of 50 mg occurring fading of extrapyramidal symptoms and decrease the symptoms of OCD.

The authors intend with this presented case to highlight the importance of surveillance of patients receiving antipsychotics for OCD to avoid worsening of symptoms and the development of extrapyramidal effects, which deeply contribute to the decrease of quality life of these patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.