Children's Anaesthesia and perioperative care challenges, and innovations

The 2015 Sustainable Development Goals emphasise good health to all with reduced inequalities, and surgical and anaesthesia care is essential to achieve these. https://sdgs.un.org/goals. However, it has been estimated that 1.7 billion children do not have access to safe anaesthesia and surgery when needed and this disproportionately affects children in low- and middle-income countries (1). It is alarming that 1 in 10 individuals in LMICs do not have access to safe surgical care. Both safe surgery and anaesthesia are essential for ensuring that individuals receive proper medical attention. Economically viable public health initiatives that can avert many disability-adjusted years are needed. (2-4) Morbidity and mortality from surgical disease and anaesthesia care remain high in low-income countries, unlike in high-income countries. The incidence of severe anaesthesia-related critical events and perioperative cardiac arrest is between three and ten times more in LMICs than in HICs (5-7) A baseline POMR that is 100 times higher in LMICs compared to HICs is reported. (8) This perioperative morbidity and mortality gap is more evident in neonates and younger age groups, especially in children with congenital abnormalities. The challenges facing providers of anaesthesia and perioperative care are multifactorial and include but are not limited to the inadequate workforce, inadequate and inappropriate infrastructure, lack of adequate and appropriately sized equipment, including monitors, and safe monitoring capacity, supply chain challenges for medicines and reusable consumables, unreliable supply of oxygen and blood products, lack of data and research for policy formulation, inadequate resource allocation from governments and lack of safety culture among other things. In paediatrics, this is further multiplied by the variability in the sizes of the patients, from neonates to older children (9).

Unpaid caregiving for people following hip fracture: longitudinal analysis from the English Longitudinal Study of Ageing

PURPOSE

To determine the provision and its change over time in unpaid care for people following hip fracture.

METHODS

Data were sought from the English Longitudinal Study of Ageing (ELSA) cohort. We identified participants who self-reported experiencing a hip fracture, who had clinical and caregiving data in the previous and subsequent two data collection waves. Demographic and clinical data were collected in addition to data on provision of unpaid care, who provided care and the frequency of needs being met.

RESULTS

The analysed cohort consisted of 246 participants [150 females (61%), mean age 78.9 years (standard deviation: 8.6)]. There was an increase in the number of participants requiring unpaid care between the Pre-Fracture and Fracture Wave (29% vs. 59%), which plateaued in the subsequent two waves (56%; 51%). Although both spouse and daughters provided the most unpaid care to participants over this study period, there was an increase in support provided during the Fracture Wave by both sons and daughters. This increased support offered by spouses continued until Post-Fracture Wave 2 when this plateaued. Support provided by friends increased from 3 to 8% and brothers and sisters increased from 0 and 1% Pre-Fracture to 8% by Post-Fracture Wave 2.

CONCLUSION

These findings provide insights into who, what and how unpaid carers support people following hip fracture over time. Given the level of support unpaid carers offer, and previously reported carer stress and burden, undertaking clinical trials to assess the effectiveness of carer-patient support interventions would be valuable.

How reconfiguration of a minor injuries unit has affected service delivery during the COVID-19 pandemic: a retrospective analysis

INTRODUCTION

Redeployment of orthopaedic consultants to a minor injuries unit (MIU) during the COVID-19 pandemic provided a unique opportunity to assess the impact of early senior specialist input on patient management.

METHODS

Patient demographics, diagnosis, location of injury and disposal method were compared between three 7-day periods: during the April 2020 COVID-19 lockdown (period A), one month prior to period A (period B) and one year prior to period A (period C). Orthopaedic consultants staffed the MIU during period A, and emergency nurse practitioners staffed the MIU during periods B and C.

RESULTS

Period A witnessed higher injury severity either due to modified activities or altered healthcare-seeking behaviour during lockdown. For fractures, compared with periods B and C, period A saw a lower rate of referral to fracture clinic (41% vs 100% vs 86%, p<0.001) and higher rate of discharge (38% vs 0% vs 9%, p<0.001). The median time to fracture clinic was also longer (15 days vs 6 days vs 10 days, p<0.001), indicating earlier institution of definitive care. There were no other significant differences between periods with radiology alerts and complaints received remaining largely unchanged.

CONCLUSION

Early senior orthopaedic input in the patient journey from MIU had clear benefits, this being most true for fracture diagnoses. Earlier definitive management planning was observed as lower rates of fracture clinic referral, higher rates of discharge and deferred first fracture clinic reviews. This study highlights the benefits of greater partnership between MIU and orthopaedics. As the pandemic subsides and redeployed staff return to normal duties, a modification of this model could be utilised to ensure this partnership is sustainable.

Search for Subsolar-Mass Binaries in the First Half of Advanced LIGO's and Advanced Virgo's Third Observing Run

We report on a search for compact binary coalescences where at least one binary component has a mass between 0.2  M_{⊙} and 1.0  M_{⊙} in Advanced LIGO and Advanced Virgo data collected between 1 April 2019 1500 UTC and 1 October 2019 1500 UTC. We extend our previous analyses in two main ways: we include data from the Virgo detector and we allow for more unequal mass systems, with mass ratio q≥0.1. We do not report any gravitational-wave candidates. The most significant trigger has a false alarm rate of 0.14  yr^{-1}. This implies an upper limit on the merger rate of subsolar binaries in the range [220-24200]  Gpc^{-3} yr^{-1}, depending on the chirp mass of the binary. We use this upper limit to derive astrophysical constraints on two phenomenological models that could produce subsolar-mass compact objects. One is an isotropic distribution of equal-mass primordial black holes. Using this model, we find that the fraction of dark matter in primordial black holes in the mass range 0.2  M_{⊙}<m_{PBH}<1.0  M_{⊙} is f_{PBH}≡Ω_{PBH}/Ω_{DM}≲6%. This improves existing constraints on primordial black hole abundance by a factor of ∼3. The other is a dissipative dark matter model, in which fermionic dark matter can collapse and form black holes. The upper limit on the fraction of dark matter black holes depends on the minimum mass of the black holes that can be formed: the most constraining result is obtained at M_{min}=1  M_{⊙}, where f_{DBH}≡Ω_{DBH}/Ω_{DM}≲0.003%. These are the first constraints placed on dissipative dark models by subsolar-mass analyses.

Medical Student Perspectives on Undergraduate Oncology Education in the UK

AIMS

The British Oncology Network for Undergraduate Societies (BONUS) surveyed students who attended an oncology revision day to determine their views on the current quantity, quality and type of curriculum-based oncology teaching they have experienced.

MATERIALS AND METHODS

Students attending two BONUS revision days received a questionnaire assessing their experience of oncology teaching within the medical curriculum and interest in pursuing a future career in oncology using a 10-point Likert scale. Data were collected with informed consent to be anonymised and used for research. Student demographics and qualitative and quantitative data about experiences of oncology education were analysed.

RESULTS

In total, 451 students registered to attend the revision days. After removal of duplicates, non-responders and non-UK participants, responses from 153 students studying across years 1-6 at 22 UK medical schools were analysed. The mean quantity of oncology lectures students reported receiving was 8.9 hours and the mean quantity of clinic/ward-based oncology teaching was 7.5 hours. Ninety (62.1%) of the 145 students who responded to the relevant question reported that they had received dedicated teaching in oncology. Students who had received dedicated oncology teaching reported a statistically significantly higher mean quality 6.1 (95% confidence interval 5.6-6.5) versus 5.0 (95% confidence interval 4.3-5.5; P = 0.003) and quantity 5.2 (95% confidence interval 4.7-5.6) versus 4.3 (95% confidence interval 3.7-4.9; P = 0.03) of oncology teaching compared with those who had not received this.

CONCLUSION

Appropriate oncology education is essential for all medical students due to the high prevalence of cancer. All future doctors need the appropriate knowledge and communication skills to care for cancer patients. Our analysis provides quantitative evidence to support the value of specialist oncology teaching within the medical school curriculum in improving student-reported experience. National student-led revision days and events may widen interest in a future career in oncology and aid collaboration between oncology societies. It is important for the general undergraduate medical curriculum to integrate specialty content. An integrated curriculum should facilitate a holistic approach that spans prevention, screening, treatment and palliation rather than being split by subspeciality.

Hepatitis B virus infection and factors associated with its acquisition among adults in a Lake Victoria HIV hyperendemic fishing community in Kyotera district, Uganda: a cross-sectional observation

OBJECTIVE

To investigate hepatitis B virus (HBV) prevalence and factors associated with viral acquisition in a HIV-hyperendemic fishing community, we tested sera for anti-hepatitis B core (HBc) and hepatitis B surface antigen (HBsAg).

DESIGN

Observational cross-sectional study.

SETTING

Large fishing village on Lake Victoria, one of the HIV-hyperendemic Rakai Community Cohort Study (RCCS) sites (HIV prevalence ~40%).

PARTICIPANTS

Sample of 460 RCCS participants aged 15-49 years from survey conducted from 5 December 2016 to 13 February 2017. These proportionately included HIV-negative, HIV-positive antiretroviral therapy (ART)-naïve and HIV positive on ART participants.

RESULTS

Of the 460 participants, 49.6% (95% CI 45.0% to 54.1%) had evidence of prior HBV infection and 3.7% (95% CI 2.3% to 5.9%) were either acutely or chronically infected. HBV risk increased with age, number of lifetime sex partners and HIV seropositivity. HBV risk decreased with HIV ART use among HIV-positive participants. Prevalence of prior HBV infection was 17.1% in participants aged 15-19 years, 43.2%, 55.3% and 70.1% in participants aged 20-39, 30-39 and 40-49 years, respectively (p<0.001). Additionally, the prevalence of prior HBV infection was 23.8% in participants with 0-1 lifetime sex partners, 43.2% and 54.8% in participants with 2-3 lifetime sex partners and 4+ lifetime sex partners, respectively (p<0.001).

CONCLUSIONS

Findings from this fishing community suggest the need to provide HBV vaccination to adults at risk of sexual transmission who have not been previously immunised.

Brief Report: Mobile Phones, Sexual Behaviors, and HIV Incidence in Rakai, Uganda, From 2010 to 2018

BACKGROUND

Sub-Saharan Africa has the highest HIV incidence and prevalence in the world. In the past decade, mobile phone ownership has doubled, affecting social and sexual practices. Using longitudinal follow-up data, this study examined whether mobile phone ownership was associated with sexual behaviors and HIV incidence for youth and adults.

METHODS

The Rakai Community Cohort Study gathers demographic and sexual health information and conducts HIV testing among an open cohort in southcentral Uganda every 12-18 months.

RESULTS

Of the 10,618 participants, 58% owned a mobile phone, 69% lived in rural locations, and 77% were sexually active. Analyses were adjusted for time, location, religion, and socioeconomic status. Phone ownership was associated with increased odds of ever having had sex act for 15- to 19-year-olds [men adjusted odds ratio (AOR): 2.12, 95% confidence interval (CI): 1.78 to 2.52; women AOR: 3.20, 95% CI: 2.45 to 4.17]. Among sexually active participants, owning a phone was associated with increased odds of having 2 or more concurrent sex partners (15- to 24-year-old men AOR: 1.76, 95% CI: 1.34 to 2.32; 25 to 49-year-old men: AOR 1.81, 95% CI: 1.54 to 2.13; 25- to 49-year-old women AOR: 1.81, 95% CI: 1.32 to 2.49). For men, phone ownership was associated with increased odds of circumcision (15- to 24-year-old men AOR: 1.24, 95% CI: 1.08 to 1.41; 25- to 49-year-old men AOR: 1.12, 95% CI: 1.01 to 1.24). Phone ownership was not associated with HIV incidence.

CONCLUSION

Although mobile phone ownership was associated with sexual risk behaviors, it was not associated with increased risk of HIV acquisition. Research should continue exploring how phones can be used for reducing sexual health risk.

Artificial intelligence for detection of microsatellite instability in colorectal cancer-a multicentric analysis of a pre-screening tool for clinical application

BACKGROUND

Microsatellite instability (MSI)/mismatch repair deficiency (dMMR) is a key genetic feature which should be tested in every patient with colorectal cancer (CRC) according to medical guidelines. Artificial intelligence (AI) methods can detect MSI/dMMR directly in routine pathology slides, but the test performance has not been systematically investigated with predefined test thresholds.

METHOD

We trained and validated AI-based MSI/dMMR detectors and evaluated predefined performance metrics using nine patient cohorts of 8343 patients across different countries and ethnicities.

RESULTS

Classifiers achieved clinical-grade performance, yielding an area under the receiver operating curve (AUROC) of up to 0.96 without using any manual annotations. Subsequently, we show that the AI system can be applied as a rule-out test: by using cohort-specific thresholds, on average 52.73% of tumors in each surgical cohort [total number of MSI/dMMR = 1020, microsatellite stable (MSS)/ proficient mismatch repair (pMMR) = 7323 patients] could be identified as MSS/pMMR with a fixed sensitivity at 95%. In an additional cohort of N = 1530 (MSI/dMMR = 211, MSS/pMMR = 1319) endoscopy biopsy samples, the system achieved an AUROC of 0.89, and the cohort-specific threshold ruled out 44.12% of tumors with a fixed sensitivity at 95%. As a more robust alternative to cohort-specific thresholds, we showed that with a fixed threshold of 0.25 for all the cohorts, we can rule-out 25.51% in surgical specimens and 6.10% in biopsies.

INTERPRETATION

When applied in a clinical setting, this means that the AI system can rule out MSI/dMMR in a quarter (with global thresholds) or half of all CRC patients (with local fine-tuning), thereby reducing cost and turnaround time for molecular profiling.

Severe Acute Respiratory Syndrome Coronavirus-2 seroprevalence in South-Central Uganda, during 2019-2021

BACKGROUND

Globally, key subpopulations such as healthcare workers (HCW) may have a higher risk of contracting SARS-CoV-2. In Uganda, limited access to Personal Protective Equipment and lack of clarity on the extent/pattern of community spread may exacerbate this situation. The country established infection prevention/control measures such as lockdowns and proper hand hygiene. However, due to resource limitations and fatigue, compliance is low, posing continued onward transmission risk. This study aimed to describe extent of SARS-CoV-2 seroprevalence in selected populations within the Rakai region of Uganda.

METHODS

From 30th November 2020 to 8th January 2021, we collected venous blood from 753 HCW at twenty-six health facilities in South-Central Uganda and from 227 population-cohort participants who reported specific COVID-19 like symptoms (fever, cough, loss of taste and appetite) in a prior phone-based survey conducted (between May and August 2020) during the first national lockdown. 636 plasma specimens collected from individuals considered high risk for SARS-CoV-2 infection, prior to the first confirmed COVID-19 case in Uganda were also retrieved. Specimens were tested for antibodies to SARS-CoV-2 using the CoronaChek™ rapid COVID-19 IgM/IgG lateral flow test assay. IgM only positive samples were confirmed using a chemiluminescent microparticle immunoassay (CMIA) (Architect AdviseDx SARS-CoV-2 IgM) which targets the spike protein. SARS-CoV-2 exposure was defined as either confirmed IgM, both IgM and IgG or sole IgG positivity. Overall seroprevalence in each participant group was estimated, adjusting for test performance.

RESULTS

The seroprevalence of antibodies to SARS-CoV-2 in HCW was 26.7% [95%CI: 23.5, 29.8] with no difference by sex, age, or cadre. We observed no association between PPE use and seropositivity among exposed healthcare workers. Of the phone-based survey participants, 15.6% [95%CI: 10.9, 20.3] had antibodies to SARS-CoV-2, with no difference by HIV status, sex, age, or occupation. Among 636 plasma specimens collected prior to the first confirmed COVID-19 case, 2.3% [95%CI: 1.2, 3.5] were reactive.

CONCLUSIONS

Findings suggest high seroprevalence of antibodies to SARS-CoV-2 among HCW and substantial exposure in persons presenting with specific COVID-19 like symptoms in the general population of South-Central Uganda. Based on current limitations in serological test confirmation, it remains unclear whether seroprevalence among plasma specimens collected prior to confirmation of the first COVID-19 case implies prior SARS-CoV-2 exposure in Uganda.

Mitral annular dysjunction in surgical mitral valve prolapse

Funding Acknowledgements

Type of funding sources: None.

Introduction

Mitral valve prolapse (MVP) affects 3% of the population and is the leading indication for mitral valve surgery.[1] Mitral annular disjunction (MAD) is a structural abnormality commonly seen in patients with MVP.[2] MAD is defined as an abnormal separation (&gt;5mm) between the left atrial wall-mitral valve junction and the left ventricle myocardium,[2] associated with hypermobility and myxomatous degeneration of the mitral valve leaflets.[3]  There is a paucity of literature regarding MAD, however evidence is growing that it may be associated with ventricular arrhythmia and sudden cardiac death.[3] We examined the prevalence, imaging characteristics and clinical associations of MAD among patients who have undergone mitral valve surgery for MVP.

Methods

Single centre cohort study of consecutive patients undergoing mitral valve surgery for MVP over a 3-year period. Patient baseline characteristics, echocardiographic parameters, surgical outcomes, frequency of arrhythmic events and 3-year cardiac and all-cause mortality were recorded.  Single site data was obtained from a prospective Australia-wide cardiac surgery registry, as well as retrospective analysis of holter-monitor reports, device interrogation and review of medical records. Transthoracic echocardiogram images were re-examined, and parameters re-measured by a qualified examiner.

Results

Among 73 patients with surgical MVP, 20 patients had MAD (27.4%). The median MAD length was 8.1 (IQR 6.8-11.8) mm. The most severely affected patient had a disjunction length of 28 mm. MAD was associated with younger age at surgery (60 vs 66, P = 0.005), female sex (40.0% vs 22.6%, P = 0.138), bileaflet MVP (50% vs 10.6%, P = 0.004) and less cardiovascular comorbidities, including hypertension (25.0% vs 57.7%, P = 0.013) and hypercholesterolaemia (30.0% vs 61.5%, P = 0.016). Patients with MAD had greater mitral valve leaflet lengths, mitral annular diameters, and high-velocity systolic signal on tissue doppler of the mitral valve annulus (pickelhaube sign). Three patients in the MAD positive group had an arrhythmic event (VF or VT) at 3 years compared to one in the MAD negative group. There was no significant difference in 3-year cardiac or all-cause mortality between groups.

Conclusion

MAD is a common anatomical abnormality in patients with surgical MVP, and is easily detected on transthoracic echocardiography. It is associated with younger age at surgery, female sex, bileaflet MVP, increased leaflet length and annulus diameter. There was a signal towards increased arrhythmic events in patients with MAD despite younger age and less cardiovascular risk factors. Large longitudinal studies are needed to further assess the association of MAD with arrhythmic events to help guild appropriate investigation and risk stratification of these patients. Abstract Figure. MAD on Parasternal Long axis view  Abstract Figure. Pickelhaube sign

Point Absorber Limits to Future Gravitational-Wave Detectors

High-quality optical resonant cavities require low optical loss, typically on the scale of parts per million. However, unintended micron-scale contaminants on the resonator mirrors that absorb the light circulating in the cavity can deform the surface thermoelastically and thus increase losses by scattering light out of the resonant mode. The point absorber effect is a limiting factor in some high-power cavity experiments, for example, the Advanced LIGO gravitational-wave detector. In this Letter, we present a general approach to the point absorber effect from first principles and simulate its contribution to the increased scattering. The achievable circulating power in current and future gravitational-wave detectors is calculated statistically given different point absorber configurations. Our formulation is further confirmed experimentally in comparison with the scattered power in the arm cavity of Advanced LIGO measured by in situ photodiodes. The understanding presented here provides an important tool in the global effort to design future gravitational-wave detectors that support high optical power and thus reduce quantum noise.

Short Communication: Validation of the Asante HIV-1 Rapid Recency Assay for Detection of Recent HIV-1 Infections in Uganda

Point of care rapid recency testing for HIV-1 may be a cost-effective tool to identify recently infected individuals for incidence estimation, and focused HIV prevention through intensified contact tracing. We validated the Asante™ HIV-1 rapid recency^® assay for use in Uganda. Archived specimens (serum/plasma), collected from longitudinally observed HIV-1 recently and long-term infected participants, were tested with the Asante HIV-1 rapid recency assay per manufacturer's instructions. Previously identified antiretroviral therapy (ART)-naive samples with known seroconversions within 6 months of follow-up were tested in independent laboratories: the Rakai Health Sciences Program (RHSP) and the Uganda Virus Research Institute HIV Reference Laboratory (UVRI-HRL). In addition, samples from participants who seroconverted within 6-18 months and samples from individuals with chronic HIV-1 infection of at least 18 months duration were classified into three categories: ART naive, ART exposed with suppressed viral loads, and ART exposed with detectable viremia. Of the 85 samples seroconverting in ≤6 months, 27 and 42 samples were identified as "recent" by the Asante HIV-1 rapid recency test at the RHSP laboratory and UVRI-HRL, corresponding to sensitivities of 32% and 49%, respectively. There was 72% agreement between the laboratories (Cohen's kappa = 0.481, 95% CI = 0.317-0.646, p < .0001). Specificity was 100% (200/200) among chronically infected ART-naive samples. The Asante HIV-1 rapid recency assay had low sensitivity for detection of recent HIV-1 infections in Uganda, with substantial interlaboratory variability due to differential interpretation of the test strip bands. Specificity was excellent. Assessment of assay performance in other settings is needed to guide decisions on test utility.

Distribution of mortality patterns in cats with naturally occurring trauma: A Veterinary Committee on Trauma registry study

A greater understanding of the prognostic variables that affect the timing of death for cats with trauma may help clinicians select treatments and monitoring plans. This study investigated the mortality rate and its distribution pattern in a large population of cats to identify variables associated with the timing of trauma-related deaths. Clinical data was retrieved from the Veterinary Committee on Trauma database to determine mortality rates and timing of deaths, defined as early death (ED; <1 day post-presentation) or delayed death (DD; ≥1 day post-presentation). Multivariable logistic regression analyses were performed to identify characteristics and interventions that best predicted timing of death. Overall mortality rate for 6703 feline trauma patients with complete records was 17.2%, with 7.6% due to natural death and 92.3% due to euthanasia. Among the subset of 543 cats with trauma that died after presentation or required euthanasia due to a grave prognosis (representing an 8.1% mortality rate), EDs were more common (71.7%) than DD and the cause of death was not significantly associated with the timing of death. Clinical pathology parameters were unable to identify animals more likely to die or to require euthanasia due to a poor prognosis during hospitalisation. Factors that were significantly different for cats with ED vs. DD included the median cumulative results for the Modified Glasgow Coma Scale (MGCS) score and the Animal Trauma Triage (ATT) score, the presence of spinal trauma, administration of blood products and undertaking surgical procedures. An increased likelihood of DD rather than ED was associated with the administration of blood products (odds ratio [OR], 3.959; P = 0.019) vs. not, performing a surgical procedure (OR, 6.055; P < 0.001) vs. not, and a cumulative MGCS of 15-17 or 18 (OR, 1.947 and 3.115; P = 0.031 and P = 0.01, respectively) vs. a cumulative MGCS ≤ 11.

Severe Acute Respiratory Syndrome Coronavirus-2 Seropositivity in South-Central Uganda, During 2019 - 2021

Background: Globally, key subpopulations such as healthcare workers (HCWs) have a higher risk of contracting SARS-CoV-2. In Uganda, limited access to personal protective equipment amidst lack of clarity on the extent and pattern of the community disease burden may exacerbate this situation. We assessed SARS-CoV-2 antibody seroprevalence among high-risk sub-populations in South-central Uganda, including HCWs, persons within the general population previously reporting experiencing key COVID-19 like symptoms (fever, cough, loss of taste and smell) and archived plasma specimens collected between October 2019 â€" 18 th March 2020, prior to confirmation of COVID-19 in Uganda. Methods: From November 2020 - January 2021, we collected venous blood from HCWs at selected health facilities in South-Central Uganda and from population-cohort participants who reported specific COVID-19 like symptoms in a prior phone-based survey conducted (between May to August 2020) during the first national lockdown. Pre-lockdown plasma collected (between October 2019 and March 18 th , 2020) from individuals considered high risk for SARS-CoV-2 infection was retrieved. Specimens were tested for antibodies to SARS-CoV-2 using the CoronaChek TM rapid COVID-19 IgM/IgG lateral flow test assay. IgM only positive samples were confirmed using a chemiluminescent microparticle immunoassay (CMIA) (Architect AdviseDx SARS-CoV-2 IgM) which targets the spike protein. SARS-CoV-2 exposure was defined as either confirmed IgM, both IgM and IgG or sole IgG positivity. Results: The seroprevalence of antibodies to SARS-CoV-2 in HCWs was 21.1% [95%CI: 18.2-24.2]. Of the phone-based survey participants, 11.9% [95%CI: 8.0-16.8] had antibodies to SARS-CoV-2. Among 636 pre-lockdown plasma specimens, 1.7% [95%CI: 0.9-3.1] were reactive. Conclusions: Findings suggest a high seroprevalence of antibodies to SARS-CoV-2 among HCWs and substantial exposure in persons presenting with specific COVID-19 like symptoms in the general population of South-central Uganda. Based on current limitations in serological test confirmation, it remains unclear whether pre-lockdown seropositivity implies prior SARS-CoV-2 exposure in Uganda.

Household wealth and HIV incidence over time, rural Uganda, 1994-2018

OBJECTIVE

To examine the relationship between household wealth and HIV incidence in rural Uganda over time from 1994 to 2018. In research conducted early in the epidemic, greater wealth (i.e. higher socioeconomic status, SES) was associated with higher HIV prevalence in sub-Saharan Africa (SSA); this relationship reversed in some settings in later years.

DESIGN

Analysis of associations over time in a population-based open cohort of persons 15-49 years from 17 survey-rounds in 28 continuously followed communities of the Rakai Community Cohort Study (RCCS).

METHODS

The RCCS sample averaged 8622 individuals and 5387 households per round. Principal components analysis was used to create a nine-item asset-based measure of household wealth. Poisson regression with generalized estimating equation (GEE) and exchangeable correlation structure was used to estimate HIV incidence rate ratios (IRRs) by SES quartile, survey-round, sex, and age group.

RESULTS

From 1994 to 2018, SES rose considerably, and HIV incidence declined from 1.45 to 0.40 per 100 person-years (IRR = 0.39, 95% CI = 0.32--0.47, P < 0.001). HIV incidence was similar by SES category in the initial survey intervals (1994-1997); however, higher SES groups showed greater declines in HIV incidence over time. Multivariable analyses showed significant associations between HIV incidence and SES (IRR = 0.55 for highest compared with lowest quartile, 95% CI = 0.45--0.66, P < 0.001) controlling for time, sex, and age group.

CONCLUSION

Beyond the early years of the RCCS, higher SES was associated with lower HIV incidence and SES gradients widened over time. The poor, like other key populations, should be targeted for HIV prevention, including treatment as prevention.

Approaching the motional ground state of a 10-kg object

The motion of a mechanical object, even a human-sized object, should be governed by the rules of quantum mechanics. Coaxing them into a quantum state is, however, difficult because the thermal environment masks any quantum signature of the object's motion. The thermal environment also masks the effects of proposed modifications of quantum mechanics at large mass scales. We prepared the center-of-mass motion of a 10-kilogram mechanical oscillator in a state with an average phonon occupation of 10.8. The reduction in temperature, from room temperature to 77 nanokelvin, is commensurate with an 11 orders-of-magnitude suppression of quantum back-action by feedback and a 13 orders-of-magnitude increase in the mass of an object prepared close to its motional ground state. Our approach will enable the possibility of probing gravity on massive quantum systems.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Visual Impairment and Eye Diseases in HIV-infected People in the Antiretroviral Therapy (ART) Era in Rakai, Uganda

PURPOSE

Antiretroviral therapy reduced infectious eye diseases (EDs) in HIV-infected people. There is limited data on age-related EDs and visual impairment (VI) in people living with HIV. We report prevalence of VI and spectrum of EDs in HIV-infected people in an ART era in Rakai, Uganda.

METHODS

A philanthropic campaign during 2009-2012 provided ophthalmic services to HIV+ patients in care. Unilateral presenting visual acuity (VA) was assessed by a trained staff in HIV clinics using a 6-m Snellen chart. A slit-lamp examination by an ophthalmologist evaluated eyes with impaired acuity. A retrospective chart review was later conducted retrieving data of patients participating the ophthalmic service. VI was defined referencing WHO's ICD-11. Ophthalmic diagnosis was summarized by VI level. Logistic regressions estimated demographic associations with cataract diagnosis.

RESULTS

688 HIV+ patients were evaluated, median age was 44 (IQR: 37-50) years, 69% were female. Fifty-one percent were on ART (median duration 4, IQR: 2-5 years). Crude prevalence of moderate/severe VI and blindness were both 2%. The main diagnoses were refractive error (55%), conjunctivitis (18%), cataract (15%), and pterygium (11%). Cataract prevalences were 10%, 12%, and 26% among age groups of 19-34, 35-49, and ≥50 years, respectively. Cataract was found in 73% of the HIV+s with blindness and in 63% of those with moderate/severe VI. Older age and male sex were significantly associated with higher cataract prevalence.

CONCLUSION

VI in HIV+ patients in Rakai was mainly due to refractive error and cataract. Cataract was common in all age groups.

A multi‐institutional randomized controlled trial comparing first‐generation transrectal high‐resolution micro‐ultrasound with conventional frequency transrectal ultrasound for prostate biopsy

Objectives

To study high‐frequency 29 MHz transrectal side‐fire micro‐ultrasound (micro‐US) for the detection of clinically significant prostate cancer (csPCa) on prostate biopsy, and validate an image interpretation protocol for micro‐US imaging of the prostate.

Materials and methods

A prospective randomized clinical trial was performed where 1676 men with indications for prostate biopsy and without known prostate cancer were randomized 1:1 to micro‐US vs conventional end‐fire ultrasound (conv‐US) transrectal‐guided prostate biopsy across five sites in North America. The trial was split into two phases, before and after training on a micro‐US image interpretation protocol that was developed during the trial using data from the pre‐training micro‐US arm. Investigators received a standardized training program mid‐trial, and the post‐training micro‐US data were used to examine the training effect.

Results

Detection of csPCa (the primary outcome) was no better with the first‐generation micro‐US system than with conv‐US in the overall population (34.6% vs 36.6%, respectively, P = .21). Data from the first portion of the trial were, however, used to develop an image interpretation protocol termed PRI‐MUS in order to address the lack of understanding of the appearance of cancer under micro‐US. Micro‐US sensitivity in the post‐training group improved to 60.8% from 24.6% (P < .01), while specificity decreased (from 84.2% to 63.2%). Detection of csPCa in the micro‐US arm increased by 7% after training (32% to 39%, P < .03), but training instituted mid‐trial did not affect the overall results of the comparison between arms.

Conclusion

Micro‐US provided no clear benefit over conv‐US for the detection of csPCa at biopsy. However, it became evident during the trial that training and increasing experience with this novel technology improved the performance of this first‐generation system.

In this work high‐frequency 29 MHz transrectal side‐fire micro‐ultrasound (US) for the detection of clinically significant prostate cancer on prostate biopsy is studied, and an image interpretation protocol for micro‐US imaging of the prostate is validated.

The YouTube link is here: https://youtu.be/U2Svj-4Ae_k

Elevated liver stiffness without histological evidence of liver fibrosis in rural Ugandans

Liver fibrosis may be assessed noninvasively with transient electrography (TE). Data on the performance of TE for detecting liver fibrosis in sub-Saharan Africa are limited. We evaluated the diagnostic accuracy of TE by performing liver biopsies on persons with liver fibrosis indicated by TE. We enrolled HIV-infected and HIV-uninfected participants with TE scores consistent with at least minimal disease (liver stiffness measurement [LSM]≥7.1 kPa). Biopsies were performed and staged using the Ishak scoring system. A concordant result was defined using accepted thresholds for significant fibrosis by TE (LSM ≥ 9.3 kPa) and liver biopsy (Ishak score ≥ 2). We used modified Poisson regression methods to quantify the univariate and adjusted prevalence risk ratios (PRR) of the association between covariates and the concordance status of TE and liver biopsy in defining the presence of liver fibrosis. Of 131 participants with valid liver biopsy and TE data, only 5 participants (3.8%) had Ishak score ≥ 2 of whom 4 had LSM ≥ 9.3 kPa (sensitivity = 80%); of the 126 (96.2%) with Ishak score < 2, 76 had LSM < 9.3 kPa (specificity = 61%). In multivariable analysis, discordance was associated with female gender (adjPRR = 1.80, 95%CI 1.1-2.9; P = .019), herbal medicine use (adjPRR 1.64, 95% CI = 1.0-2.5; P = .022), exposure to lake or river water (adjPRR 2.05, 95% CI = 1.1-3.7; P = .016), and current smoking (adjPRR 1.72, 95%CI 1.0-2.9; P = .045). These data suggest that TE among rural Ugandans has low specificity for detection of histologically confirmed liver fibrosis. Caution should be exercised when using this tool to confirm significant liver fibrosis.

GW190521: A Binary Black Hole Merger with a Total Mass of 150 M_{⊙}

On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21}  M_{⊙} and 66_{-18}^{+17}  M_{⊙} (90% credible intervals). We infer that the primary black hole mass lies within the gap produced by (pulsational) pair-instability supernova processes, with only a 0.32% probability of being below 65  M_{⊙}. We calculate the mass of the remnant to be 142_{-16}^{+28}  M_{⊙}, which can be considered an intermediate mass black hole (IMBH). The luminosity distance of the source is 5.3_{-2.6}^{+2.4}  Gpc, corresponding to a redshift of 0.82_{-0.34}^{+0.28}. The inferred rate of mergers similar to GW190521 is 0.13_{-0.11}^{+0.30}  Gpc^{-3} yr^{-1}.

P1699 A case of atrial myxoma presenting with acute stroke

A 73-year-old female presented with sudden reduced level of consciousness on the background of rheumatoid arthritis and dyslipidaemia. On examination she had a Glascow Coma Score of 12 and an irregularly irregular pulse. The electrocardiograph confirmed atrial fibrillation and showed widespread T wave inversion. A computed tomography cerebral angiogram showed an acute basilar artery occlusion. She was transferred to a tertiary centre where she had successful endovascular clot retrieval. An urgent transthoracic echocardiogram (figure 1) showed apical hypertrophy, normal systolic function and a large right atrial mass. The left atrial size was normal. A transoesophageal echocardiogram (figure 3) confirmed a large pedunculated mobile mass with a hypermobile septum consistent with a patent foramen ovale. There was no right to left doppler flow, however the atrial mass obstructed the course, and a bubble study was positive. The cardiac magnetic resonance image (figure 2) showed a 47 x 48 mm pedunculated lesion within the right atrium, arising from the intraventricular septum, demonstrating moderate T2 signal intensity, and intermediate T1 signal intensity, with avid enhancement, consistent with a right atrial myxoma. There was increased apical wall thickening at 15mm which confirmed apical hypertrophic cardiomyopathy. An open surgical resection and left atrial appendage ligation was performed on day 11 of admission. Histopathology confirmed an atrial myxoma. She had an excellent neurological recovery with only mild diplopia. The mechanism of stroke was likely atrial fibrillation secondary to increased left atrial pressure from apical hypertrophic cardiomyopathy. However, the unexpected finding of a right atrial myxoma with a corresponding patent foramen ovale provides a second possible mechanism.

Abstract P1699 Figure. Right atrial Myxoma

Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA

We present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star-black hole, and binary black hole systems. The ability to localize the sources is given as a sky-area probability, luminosity distance, and comoving volume. The median sky localization area (90% credible region) is expected to be a few hundreds of square degrees for all types of binary systems during O3 with the Advanced LIGO and Virgo (HLV) network. The median sky localization area will improve to a few tens of square degrees during O4 with the Advanced LIGO, Virgo, and KAGRA (HLVK) network. During O3, the median localization volume (90% credible region) is expected to be on the order of 10 5 , 10 6 , 10 7 Mpc 3 for binary neutron star, neutron star-black hole, and binary black hole systems, respectively. The localization volume in O4 is expected to be about a factor two smaller than in O3. We predict a detection count of 1 - 1 + 12 ( 10 - 10 + 52 ) for binary neutron star mergers, of 0 - 0 + 19 ( 1 - 1 + 91 ) for neutron star-black hole mergers, and 17 - 11 + 22 ( 79 - 44 + 89 ) for binary black hole mergers in a one-calendar-year observing run of the HLV network during O3 (HLVK network during O4). We evaluate sensitivity and localization expectations for unmodeled signal searches, including the search for intermediate mass black hole binary mergers.

Quantum-Enhanced Advanced LIGO Detectors in the Era of Gravitational-Wave Astronomy

The Laser Interferometer Gravitational Wave Observatory (LIGO) has been directly detecting gravitational waves from compact binary mergers since 2015. We report on the first use of squeezed vacuum states in the direct measurement of gravitational waves with the Advanced LIGO H1 and L1 detectors. This achievement is the culmination of decades of research to implement squeezed states in gravitational-wave detectors. During the ongoing O3 observation run, squeezed states are improving the sensitivity of the LIGO interferometers to signals above 50 Hz by up to 3 dB, thereby increasing the expected detection rate by 40% (H1) and 50% (L1).

Anaesthetic management of a three-month-old baby for cervical limited dorsal myeloschisis repair using propofol and alfentanil infusions guided by pharmacokinetic simulation software: A case report

We present an uncommon case of limited dorsal myeloschisis in a 3-month-old infant requiring repair guided by intraoperative neuromonitoring (IONM) and therefore avoidance of volatile anaesthetic agents. The case presented challenges in positioning, airway management, a lack of age appropriate pharmacokinetic models in target-controlled infusion (TCI) syringe pumps and unavailability of remifentanil, considered to be an essential drug in this setting. We overcame these challenges using manually controlled infusions of propofol and alfentanil guided by pharmacokinetic simulation software (Stelsim).

Search for Subsolar Mass Ultracompact Binaries in Advanced LIGO's Second Observing Run

We present a search for subsolar mass ultracompact objects in data obtained during Advanced LIGO's second observing run. In contrast to a previous search of Advanced LIGO data from the first observing run, this search includes the effects of component spin on the gravitational waveform. We identify no viable gravitational-wave candidates consistent with subsolar mass ultracompact binaries with at least one component between 0.2  M_{⊙}-1.0  M_{⊙}. We use the null result to constrain the binary merger rate of (0.2  M_{⊙}, 0.2  M_{⊙}) binaries to be less than 3.7×10^{5}  Gpc^{-3} yr^{-1} and the binary merger rate of (1.0  M_{⊙}, 1.0  M_{⊙}) binaries to be less than 5.2×10^{3}  Gpc^{-3} yr^{-1}. Subsolar mass ultracompact objects are not expected to form via known stellar evolution channels, though it has been suggested that primordial density fluctuations or particle dark matter with cooling mechanisms and/or nuclear interactions could form black holes with subsolar masses. Assuming a particular primordial black hole (PBH) formation model, we constrain a population of merging 0.2  M_{⊙} black holes to account for less than 16% of the dark matter density and a population of merging 1.0  M_{⊙} black holes to account for less than 2% of the dark matter density. We discuss how constraints on the merger rate and dark matter fraction may be extended to arbitrary black hole population models that predict subsolar mass binaries.

Abstract P1-11-13: Depomedroxyprogesterone therapy for hot flashes in survivors of ER-expressing breast cancer: Impact on recurrence and survival

Background

Survivors of ER-expressing operable breast cancer (ER+BC) generally do not receive hormone replacement therapy for menopausal symptoms due to concern about provoking recurrence of disease. Single dose depomedroxyprogesterone acetate (MPA) 400 mg IM has previously been shown (Loprinzi CL, et al. J Clin Oncol 2006;24:1409) to be the most effective non-estrogen therapy available for menopausal hot flashes (HF) but long-term evidence of safety in survivors of ER+BC is lacking.

Methods

Consecutive patients previously diagnosed with ER+BC who received MPA for HF between January 2007 and December 2012 were retrospectively identified in the breast cancer patient database at Mayo Clinic Arizona. Medical records were audited for breast cancer outcomes in these cases and in contemporaneous control patients with ER+BC who did not receive MPA, matched for age, stage of disease, and year of diagnosis. Statistical comparisons of local-regional recurrence and event-free survival were performed.

Results

92 patients who received MPA were identified and matched 1:1 with contemporaneous controls. Median follow-up duration was 5.7 years in cases and 4.5 years in controls. Estimated local-regional recurrence free survival at 10 years was 85% (95% CI, 72-100%) in cases and 95% (95% CI, 86-100%) in controls. Matched pairs hazard ratio was 1.0 (95% CI, 0.06-16.0) for local-regional recurrence free survival. Estimated event-free survival at 10 years was 81% (95% CI, 69-97%) in cases and 76% (95% CI, 64-92%) in controls. Matched pairs hazard ratio was 0.38 (95% CI, 0.10-1.41) for event-free survival. The majority (77%) of case patients experienced satisfactory relief of hot flashes from MPA injection.

Conclusion

In this retrospective case-control study we were unable to identify a detrimental effect of MPA therapy for HF in survivors of ER+BC. MPA may be acceptable for management of HF in this population.

Citation Format: Ertz-Archambault N, Rogoff L, Kosiorek H, Ernst B, Anderson K, Pockaj B, Gray R, Northfelt D. Depomedroxyprogesterone therapy for hot flashes in survivors of ER-expressing breast cancer: Impact on recurrence and survival [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-11-13.