Trends in use of intraosseous and intravenous access in out-of-hospital cardiac arrest across English ambulance services : a registry-based, cohort study

Introduction: The optimum route for drug administration in cardiac arrest is unclear. Recent data suggest that use of the intraosseous route may be increasing. This study aimed to explore changes over time in use of the intraosseous and intravenous drug routes in out-of-hospital cardiac arrest in England. Methods: We extracted data from the UK Out-of-Hospital Cardiac Arrest Outcomes registry. We included adult out-of-hospital cardiac arrest patients between 2015–2020 who were treated by an English Emergency Medical Service that submitted vascular access route data to the registry. The primary outcome was any use of the intraosseous route during cardiac arrest. We used logistic regression models to describe the association between time (calendar month) and intraosseous use. Results: We identified 75,343 adults in cardiac arrest treated by seven Emergency Medical Service systems between January 2015 and December 2020. The median age was 72 years, 64% were male and 23% presented in a shockable rhythm. Over the study period, the percentage of patients receiving intraosseous access increased from 22.8% in 2015 to 42.5% in 2020. For each study-month, the odds of receiving any intraosseous access increased by 1.019 (95% confidence interval 1.019 to 1.020, p < 0.001). This observed effect was consistent across sensitivity analyses. We observed a corresponding decrease in use of intravenous access. Conclusion: In England, the use of intraosseous access in out-of-hospital cardiac arrest has progressively increased over time. There is an urgent need for randomised controlled trials to evaluate the clinical effectiveness of the different vascular access routes in cardiac arrest

BIOMARKER SURVEILLANCE IN WOMEN OF REPRODUCTIVE AGE FOR ANEMIA AND BIRTH DEFECTS PREVENTION

302 pagesBackground: Women of reproductive age (WRA) are a high-risk population for anemia and micronutrient deficiencies. Population-based biomarker data is needed to inform interventions and public health programs for anemia and birth defects prevention. Methods: Participants were 979 WRA (15-40y; not pregnant or lactating) from a population-based surveillance program in Southern India. Sociodemographic, nutritional, metabolic, and clinical data were collected using structured interviewers; a women’s health questionnaire (WHQ) was used to characterize reproductive histories and risk factors for birth defects. Venous whole blood samples were collected and analyzed for hemoglobin. Plasma, serum, and red blood cells (RBC) were processed and stored until batch analysis after data collection. RBC folate and serum folate (via WHO-recommended microbiologic assay), total vitamin B12 (via chemiluminescence), and anemia (via HemoCue 301 and automated Coulter HMX; AHA) were evaluated. Continuous variables were described using geometric means (GM) and 95% confidence intervals. Bayesian linear models were used to estimate the unadjusted and adjusted serum folate insufficiency threshold (sf-IT) for optimal neural tube defect prevention. Diagnostic accuracy parameters were calculated to evaluate screening methods for hemoglobin and anemia assessment using paired venous samples. Results: The prevalence of anemia (41.6%) and nutritional and metabolic risk factors for birth defects in this population was substantial. A total of 79.3% of women had RBC folate concentrations below the threshold for optimal NTD prevention. Among WRA with sufficient vitamin B12 status (≥221 pmol/L), the estimated sf-IT was consistent with previous Bayesian analyses. The estimated sf-IT increased in women with vitamin B12 deficiency (<148 pmol/L) or elevated MMA and was lower in WRA with elevated metabolic risk factors. The estimated prevalence of anemia was lower via portable hemoglobinometer compared to the AHA reference (36.3% vs. 41.6%), and its sensitivity was higher in WRA with iron deficiency and lower in WRA with elevated metabolic risk factors. Conclusions: The prevalence of risk factors for birth defects, including RBC folate insufficiency, and anemia were substantial in this population. Population-based biomarker surveillance in women of reproductive age is needed to inform anemia and birth defects prevention.2024-06-0

Vitamin B₁₂ Status in Pregnant Adolescents and Their Infants

Vitamin B12 deficiency has been associated with increased risk of adverse pregnancy outcomes. Few prospective studies have investigated the burden or determinants of vitamin B12 deficiency early in life, particularly among pregnant adolescents and their children. The objectives of this study were to determine the prevalence of vitamin B12 deficiency and to examine associations between maternal and neonatal vitamin B12 status in a cohort study of healthy pregnant adolescents. Serum vitamin B12 and folate concentrations were measured in adolescents at mid-gestation (n = 124; 26.4 &#177; 3.5 weeks) and delivery (n = 131; 40.0 &#177; 1.3 weeks), and in neonates at birth using cord blood. Linear regression was used to examine associations between maternal and neonatal vitamin B12 status. Although the prevalence of vitamin B12 deficiency (&lt;148.0 pmol/L; 1.6%) in adolescents was low during pregnancy, 22.6% of adolescents were vitamin B12 insufficient (&lt;221.0 pmol/L; 22.6%) at mid-gestation. Maternal vitamin B12 concentrations significantly decreased from mid-gestation to delivery (p &lt; 0.0001), and 53.4% had insufficient vitamin B12 status at delivery. Maternal vitamin B12 concentrations (p &lt; 0.001) and vitamin B12 deficiency (p = 0.002) at delivery were significantly associated with infant vitamin B12 concentrations in multivariate analyses, adjusting for gestational age, maternal age, parity, smoking status, relationship status, prenatal supplement use, pre-pregnancy body mass index, race, and intake of vitamin B12 and folate. Maternal vitamin B12 concentrations significantly decreased during pregnancy and predicted neonatal vitamin B12 status in a cohort of healthy pregnant adolescents