Case 12 : Policy Meets Practice – People Who Inject Drugs (PWID)

Dr. Silverman is the Chief of Infectious Diseases at London Health Sciences Centre (LHSC) and St. Joseph’s Health Care in London, Ontario. He is concerned about the increasing prevalence of people who inject drugs (PWID) in London, and the risk to PWID of bacterial infections due to contamination (e.g., improperly or unsterilized injection equipment, skin not being sterilized before injection). Of primary concern is the risk of infective endocarditis (IE), an infection in a patient’s heart. Treatment for IE entails antibiotics administered through the intravenous (IV) route. IE is generally treated through home care; in London, the South West Community Care Access Centre (CCAC) is responsible for delivering home care. To treat IE at home, a patient would need a peripherally inserted central catheter (a PICC-line) and assistance from a CCAC nurse to administer the antibiotics. This option, however, is not viable for some patients, including those who fall under the category of PWID or who may not have a fixed address. In the case of PWID, the PICC-line, in effect, becomes a “highway” for injecting other drugs; in instances where a patient may not have secure housing or be homeless, the CCAC nurse may not be able to track down the individual. When a patient in one of these situations is being treated for IE, it puts the care team in a difficult position. The alternatives to home care are hospital admittance or no treatment at all, neither of which are ideal solutions. Dr. Silverman is currently in this position, as he must decide on a treatment plan for Mr. W., a patient who has IE, has struggled with drug addiction (the likely cause of his IE), and who does not have stable housing. In making his decision, Dr. Silverman has included on Mr. W.’s care team two other physicians from LHSC, a representative from the CCAC, and the managing director of London CAReS, a community-based housing-first organization. The care team must determine the best treatment plan for Mr. W

Digital technology and disease surveillance in the COVID-19 pandemic: A scoping review protocol

Introduction Infectious diseases pose a risk to public health, requiring efficient strategies for disease prevention. Digital health surveillance technologies provide new opportunities to enhance disease prevention, detection, tracking, reporting and analysis. However, in addition to concerns regarding the effectiveness of these technologies in meeting public health goals, there are also concerns regarding the ethics, legality, safety and sustainability of digital surveillance technologies. This scoping review examines the literature on digital surveillance for public health purposes during the COVID-19 pandemic to identify health-related applications of digital surveillance technologies, and to highlight discussions of the implications of these technologies. Methods and analysis The scoping review will be guided by the framework proposed by Arksey and O\u27Malley and the guidelines outlined by Colquhoun et al and Levac et al. We will search Medline (Ovid), PsycInfo, PubMed, Scopus, CINAHL (EBSCOhost), ACM Digital Library, Google Scholar and IEEE Explore for relevant studies published between December 2019 and December 2020. The review will also include grey literature. Data will be managed and analysed through an extraction table and thematic analysis. Ethics and dissemination Findings will be disseminated through traditional academic channels, as well as social media channels and research briefs and infographics. We will target our dissemination to provincial and federal public health organisations, as well as technology companies and community-based organisations managing the public response to the COVID-19 pandemic

Children with severe acute asthma admitted to Dutch PICUs: A changing landscape

The number of children requiring pediatric intensive care unit (PICU) admission for severe acute asthma (SAA) around the world has increased. Objectives: We investigated whether this trend in SAA PICU admissions is present in the Netherlands. Methods: A multicenter retrospective cohort study across all tertiary care PICUs in the Netherlands. Inclusion criteria were children (2-18 years) hospitalized for SAA between 2003 and 2013. Data included demographic data, asthma diagnosis, treatment, and mortality. Results: In the 11-year study period 590 children (660 admissions) were admitted to a PICU with a threefold increase in the number of admissions per year over time. The severity of SAA seemed unchanged, based on the first blood gas, length of stay and mortality rate (0.6%). More children received highflow nasal cannula (P<0.001) and fewer children needed invasive ventilation (P<0.001). In 58% of the patients the maximal intravenous (IV) salbutamol infusion rate during PICU admission was 1mcg/kg/min. However, the number of patients treated with IV salbutamol in the referring hospitals increased significantly over time (P=0.005). The proportion of steroid-naïve patients increased from 35% to 54% (P=0.004), with a significant increase in both age groups (2-4 years [P=0.026] and 5-17 years [P=0.036]). Conclusions: The number of children requiring PICU admission for SAA in the Netherlands has increased. We speculate that this threefold increase is explained by an increasing number of steroid-naïve children, in conjunction with a lowered threshold for PICU admission, possibly caused by earlier use of salbutamol IV in the referring hospitals

Dipolar origin of the gas-liquid coexistence of the hard-core 1:1 electrolyte model

We present a systematic study of the effect of the ion pairing on the gas-liquid phase transition of hard-core 1:1 electrolyte models. We study a class of dipolar dimer models that depend on a parameter R_c, the maximum separation between the ions that compose the dimer. This parameter can vary from sigma_{+/-} that corresponds to the tightly tethered dipolar dimer model, to R_c --> infinity, that corresponds to the Stillinger-Lovett description of the free ion system. The coexistence curve and critical point parameters are obtained as a function of R_c by grand canonical Monte Carlo techniques. Our results show that this dependence is smooth but non-monotonic and converges asymptotically towards the free ion case for relatively small values of R_c. This fact allows us to describe the gas-liquid transition in the free ion model as a transition between two dimerized fluid phases. The role of the unpaired ions can be considered as a perturbation of this picture.Comment: 16 pages, 13 figures, submitted to Physical Review

Cerebrovascular responses to graded exercise in young healthy males and females

Although systemic sex‐specific differences in cardiovascular responses to exercise are well established, the comparison of sex‐specific cerebrovascular responses to exercise has gone under‐investigated especially, during high intensity exercise. Therefore, our purpose was to compare cerebrovascular responses in males and females throughout a graded exercise test (GXT). Twenty‐six participants (13 Females and 13 Males, 24 ± 4 yrs.) completed a GXT on a recumbent cycle ergometer consisting of 3‐min stages. Each sex completed 50W, 75W, 100W stages. Thereafter, power output increased 30W/stage for females and 40W/stage for males until participants were unable to maintain 60‐80 RPM. The final stage completed by the participant was considered maximum workload(Wmax). Respiratory gases (End‐tidal CO2, EtCO2), middle cerebral artery blood velocity (MCAv), heart rate (HR), non‐invasive mean arterial pressure (MAP), cardiac output (CO), and stroke volume (SV) were continuously recorded on a breath‐by‐breath or beat‐by‐beat basis. Cerebral perfusion pressure, CPP = MAP (0. 7,355 distance from heart‐level to doppler probe) and cerebral vascular conductance index, CVCi = MCAv/CPP 100mmHg were calculated. The change from baseline (Δ) in MCAv was similar between the sexes during the GXT (p = .091, ωp2 = 0.05). However, ΔCPP (p < .001, ωp2 = 0.25) was greater in males at intensities ≥ 80% Wmax and ΔCVCi (p = .005, ωp2 = 0.15) was greater in females at 100% Wmax. Δ End‐tidal CO2 (ΔEtCO2) was not different between the sexes during exercise (p = .606, ωp2 = −0.03). These data suggest there are sex‐specific differences in cerebrovascular control, and these differences may only be identifiable at high and severe intensity exercise.Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye

Maternal iron deficiency perturbs embryonic cardiovascular development in mice.

Congenital heart disease (CHD) is the most common class of human birth defects, with a prevalence of 0.9% of births. However, two-thirds of cases have an unknown cause, and many of these are thought to be caused by in utero exposure to environmental teratogens. Here we identify a potential teratogen causing CHD in mice: maternal iron deficiency (ID). We show that maternal ID in mice causes severe cardiovascular defects in the offspring. These defects likely arise from increased retinoic acid signalling in ID embryos. The defects can be prevented by iron administration in early pregnancy. It has also been proposed that teratogen exposure may potentiate the effects of genetic predisposition to CHD through gene-environment interaction. Here we show that maternal ID increases the severity of heart and craniofacial defects in a mouse model of Down syndrome. It will be important to understand if the effects of maternal ID seen here in mice may have clinical implications for women

Children with severe acute asthma admitted to Dutch PICUs:A changing landscape

The number of children requiring pediatric intensive care unit (PICU) admission for severe acute asthma (SAA) around the world has increased. OBJECTIVES: We investigated whether this trend in SAA PICU admissions is present in the Netherlands. METHODS: A multicenter retrospective cohort study across all tertiary care PICUs in the Netherlands. Inclusion criteria were children (2-18 years) hospitalized for SAA between 2003 and 2013. Data included demographic data, asthma diagnosis, treatment, and mortality. RESULTS: In the 11-year study period 590 children (660 admissions) were admitted to a PICU with a threefold increase in the number of admissions per year over time. The severity of SAA seemed unchanged, based on the first blood gas, length of stay and mortality rate (0.6%). More children received highflow nasal cannula (P < 0.001) and fewer children needed invasive ventilation (P < 0.001). In 58% of the patients the maximal intravenous (IV) salbutamol infusion rate during PICU admission was 1 mcg/kg/min. However, the number of patients treated with IV salbutamol in the referring hospitals increased significantly over time (P = 0.005). The proportion of steroid-naïve patients increased from 35% to 54% (P = 0.004), with a significant increase in both age groups (2-4 years [P = 0.026] and 5-17 years [P = 0.036]). CONCLUSIONS: The number of children requiring PICU admission for SAA in the Netherlands has increased. We speculate that this threefold increase is explained by an increasing number of steroid-naïve children, in conjunction with a lowered threshold for PICU admission, possibly caused by earlier use of salbutamol IV in the referring hospitals

Maternal iron deficiency perturbs embryonic cardiovascular development in mice

Funder: Novo Nordisk; doi: https://doi.org/10.13039/501100004191Funder: National Heart Foundation of Australia (Heart Foundation); doi: https://doi.org/10.13039/501100001030Funder: NSW Health; doi: https://doi.org/10.13039/501100009287Funder: Oxford University | John Fell Fund, University of Oxford (John Fell OUP Research Fund); doi: https://doi.org/10.13039/501100004789Funder: The Federated FoundationAbstract: Congenital heart disease (CHD) is the most common class of human birth defects, with a prevalence of 0.9% of births. However, two-thirds of cases have an unknown cause, and many of these are thought to be caused by in utero exposure to environmental teratogens. Here we identify a potential teratogen causing CHD in mice: maternal iron deficiency (ID). We show that maternal ID in mice causes severe cardiovascular defects in the offspring. These defects likely arise from increased retinoic acid signalling in ID embryos. The defects can be prevented by iron administration in early pregnancy. It has also been proposed that teratogen exposure may potentiate the effects of genetic predisposition to CHD through gene–environment interaction. Here we show that maternal ID increases the severity of heart and craniofacial defects in a mouse model of Down syndrome. It will be important to understand if the effects of maternal ID seen here in mice may have clinical implications for women