Sonographic Predictors of Antepartum Bleeding in Placenta Previa.

OBJECTIVE: To evaluate the association between sonographic features of placenta previa and vaginal bleeding (VB). STUDY DESIGN: Retrospective cohort study of women with placenta previa identified on ultrasound between 160/7 and 276/7 weeks gestation. Placental distance past the cervical os (DPO), placental thickness, edge angle, and cervical length (CL) were measured. The primary outcome was any VB and the secondary outcome was VB requiring delivery. Median values of the sonographic features were compared for each of the outcomes using the Mann-Whitney U test. Receiver operating characteristic curves were used to compare the predictive value of sonographic variables markers and to determine optimal cut points for each measurement. Logistic regression was used to estimate the association between each measure and the outcomes while controlling for confounders. RESULTS: Of 149 women with placenta previa, 37% had VB and 15% had VB requiring delivery. Women with VB requiring delivery had significantly more episodes of VB than those who did not require delivery for VB (1.5, interquartile range [IQR] [1-3] vs 1.0 [1-5]; p = 0.001). In univariate analysis, women with VB had decreased CL (3.9 vs. 4.2 cm; p < 0.01) compared with those without. Women with VB requiring delivery had increased DPO (2.6 cm IQR [1.7-3.3] vs. 1.5 cm [1.1-2.4], p = 0.01) compared with those without. After adjusting for confounders, only CL < 4 cm remained independently associated with increased risk of VB (adjusted odds ratio: 2.27, 95% confidence interval [1.12-4.58], p = 0.01). None of the measures were predictive of either outcome (area under the curve < 0.65). CONCLUSION: Decreased CL may be associated with risk of VB in placenta previa. KEY POINTS: · Placenta previa is associated with VB.. · Sonographic markers of placenta previa are associated with VB.. · CL is associated with VB in placenta previa, whereas placental DPO is associated with higher rates of bleeding leading to delivery..

Military healthcare system mitigates racial disparities for severe maternal morbidity from preeclampsia.

BACKGROUND: In the United States, Black women die at 2.5 times the rate of White women and 3.5 times the rate of Hispanic women. These racial health care disparities have been largely attributed to access to health care and other social determinants of health. OBJECTIVE: We hypothesize that the Military healthcare system models universal health care access seen in other developed countries and should equalize these rates. STUDY DESIGN: Delivery data from 41 Military treatment facilities across the Department of Defense (Army, Air Force, and Navy) including over 36,000 deliveries from 2019 to 2020 were compiled in a convenience dataset through the National Perinatal Information Center. After aggregation, the parameters of percent of deliveries complicated by Severe Maternal Morbidity and percent of severe maternal morbidity secondary to pre-eclampsia with and without transfusion were calculated. Risk ratios were calculated by race for the resulting summary data. American Indian/Alaska Native were excluded because of limited total number deliveries preventing statistical analyses. RESULTS: Overall, the risk of severe maternal morbidity was increased among Black women compared to White women. The risk of severe maternal morbidity related to pre-eclampsia showed no significant difference among races with or without transfusion. When other races were set as reference group, there was a significant difference for White women, suggesting a protective effect. CONCLUSION: Although women of color still experience overall severe maternal morbidity at higher rates than their White counterparts, TRICARE may have equalized the risk of severe maternal morbidity for deliveries complicated by pre-eclampsia.

Increased maternal morbidity and mortality among Asian American and Pacific Islander women in the military health system.

BACKGROUND: Rates of maternal morbidity and mortality experienced by women in the United States have been shown to vary significantly by race, most commonly attributed to differences in access to healthcare and socioeconomic status. Recent data showed that Asian Pacific Islanders have the highest rate of maternal morbidity despite having a higher socioeconomic status. In the military, women of all races are granted equal access to healthcare, irrespective of socioeconomic class. We hypothesized that within the military, there would be no racial disparities in maternal outcomes because of universal healthcare. OBJECTIVE: This study aimed to evaluate if universal access to healthcare, as seen in the military healthcare system, leads to similar rates of maternal morbidity regardless of racial or ethnic background. STUDY DESIGN: This was a retrospective cohort study of data from the National Perinatal Information Center reports obtained from participating military treatment facilities from April 2019 to March 2020 and included 34,025 deliveries. We compared racial differences in the incidence of each of the following 3 outcomes: postpartum hemorrhage, severe maternal morbidity among women with postpartum hemorrhage including transfusion, and severe maternal morbidity among women with postpartum hemorrhage excluding transfusion. RESULTS: A total of 41 military treatment facilities (a list of participating military treatment facilities are provided in the Appendix) provided data that were included. There was an increased rate of postpartum hemorrhage (relative risk, 1.73; 95% confidence interval, 1.45-2.07), severe maternal morbidity including transfusion (relative risk, 1.22; 95% confidence interval, 0.93-1.61), and severe maternal morbidity excluding transfusion (relative risk, 1.97; 95% confidence interval, 1.02-3.8) among Asian Pacific Islander women when compared with Black or White women. CONCLUSION: Even with equal access to healthcare in the military, Asian Pacific Islander women experience statistically significant increased rates of postpartum hemorrhage and severe maternal morbidity excluding transfusion when compared with Black or White women. The increased rates of severe maternal morbidity including transfusion were not statistically significant.

Mediastinal Mass Discovered in the Second Trimester, a Rare Presentation of Hodgkin's Lymphoma in Pregnancy.

Newly diagnosed malignancy during pregnancy is rare affecting approximately 1 in 1,000 pregnancies. Breast followed by hematologic malignancies are most common. Hodgkin's lymphoma (HL) is a lymphoid neoplasm which can present with lymphadenopathy or mediastinal mass and represents 6% of all malignancies diagnosed during pregnancy. Treatment involves a combination of chemotherapy with or without adjuvant radiation which poses significant challenges when diagnosed antepartum. We highlight a 28-year-old primigravida at 26 weeks gestation who presented to the emergency department in Japan with cough, dyspnea, and sore throat for 3-5 days. Initial chest radiography demonstrated a large perihilar mass with mediastinal shift. Follow-up CT chest revealed an anterior mediastinal mass measuring 8 cm × 19 cm × 16 cm with features concerning for aggressive lymphoma. The patient was subsequently transferred to a stateside tertiary care center for expedited workup. She underwent two core needle biopsies, both of which were non-diagnostic. Cardiothoracic surgery performed a cervical mediastinoscopy with excision of the enlarged right supraclavicular lymph node. Pathologic analysis revealed classical HL, nodular sclerosis subtype. Treatment was initiated with adriamycin, bleomycin, vinblastine, and dacarbazine with two cycles planned antepartum followed by additional cycles postpartum. The patient had an uncomplicated vaginal delivery at 38 weeks gestation. Diagnosis of HL in pregnancy is rare, and expedited diagnosis can be challenging as multiple diagnostic and treatment modalities may impact pregnancy. Management in pregnancy requires a multidisciplinary approach, and decisions regarding treatment and delivery timing should be weighed against risk to the fetus.

Interrupted versus continuous magnesium sulfate and blood loss at cesarean delivery.

OBJECTIVE: Magnesium sulfate is standard of care for prevention of eclampsia in women with preeclampsia with severe features. The American College of Obstetrics and Gynecology endorses its use throughout labor, delivery and the immediate postpartum period. Some providers pause magnesium sulfate infusion preoperatively due to concern for increased risk of uterine atony and postpartum hemorrhage. Using a non-inferiority analysis, we investigated the effect of interrupted versus continuous infusion of magnesium sulfate on postpartum hemorrhage in women with preeclampsia with severe features undergoing cesarean delivery. STUDY DESIGN: Retrospective non-inferiority cohort study of women with preeclampsia with severe features treated with magnesium sulfate undergoing cesarean delivery with singleton pregnancies at tertiary care hospital from 2013 to 2018. The primary outcome was postpartum hemorrhage. Secondary outcomes included estimated blood loss, change in hematocrit and a composite of postpartum hemorrhage severity, including transfusion of blood products, use of more than one uterotonic and additional surgical interventions. RESULTS: Of 249 women, magnesium sulfate infusion was interrupted in 171 (69%) and continued in 78 (31%). Women with interrupted magnesium sulfate infusion were more likely to be Caucasian (73% vs 67%, p = .024), have chronic hypertension (23% vs 1%, p < .001), labor prior to cesarean delivery (84% vs 55%, p < .001), undergo primary cesarean delivery (86% vs 67%, p = .005), and experience shorter surgical time (50 vs 55 min, p = .026). The rate of postpartum hemorrhage for those receiving interrupted magnesium sulfate infusion (9.9%) and continuous magnesium sulfate infusion (10.2%) was similar, falling within the non-inferiority margin (absolute difference 0.3%, 95% CI -7.8 to 8.4%, p = .88). There were no significant differences in the secondary outcomes. CONCLUSION: Interrupted magnesium sulfate infusion is non-inferior to continued magnesium sulfate infusion for rates of postpartum hemorrhage in women with preeclampsia with severe features undergoing cesarean delivery.

Low-dose aspirin increases 15-epi-lipoxins A4 in pregnancies at high-risk for developing preeclampsia.

BACKGROUND: LDA triggers biosynthesis of endogenous anti-inflammatory molecules, aspirin-triggered 15-epi-lipoxin A4 (15-epi-LXA4), which may counteract inflammatory process of preeclampsia (PE), and play role in LDA's mechanism of action in PE prevention in high-risk patients. OBJECTIVE: Investigate the effects of daily LDA on levels of 15-epi-LXA4 in pregnancies at high-risk for developing PE. MATERIALS AND METHODS: Secondary analysis of multi-centered randomized controlled trial investigating effects of daily LDA (60 mg) in high-risk pregnancies. Maternal samples were drawn at three points: before LDA initiation (13-26 weeks' gestation), 24-28 weeks' gestation (at least two weeks after LDA) and 34-36 weeks' gestation. 15-epi-LXA4 levels were measured by ELISA. RESULTS: Analysis included 82 patients: 63 receiving daily LDA and 29 receiving daily placebo starting between 13 and 25 weeks gestation. Prior to randomization, baseline 15-epi-LXA4 levels were similar between both groups (75.9 pg/mL [IQR; 63.8-114.0] vs 136.2 pg/mL [52.4-476.2]; p = 0.10). Patients receiving daily LDA were noted to have significantly increased levels of 15-epi-LXA4 after LDA administration (136.2 pg/mL [IQR; 52.4-476.2] vs 1758.2 pg/mL [905.4-6638.5]; p < 0.001). They also had higher 15-epi-LXA4 levels compared to those receiving placebo at 24-28 weeks' (50.3 [38.1-94.2] vs 1758.2 [905.4-6638.5]; p < 0.001 and 34-38 weeks' gestation (57.9 [41.9-76.7] vs 2310.3 pg/mL [656.9-10609.4]; p < 0.001). After LDA administration in the second trimester, patients who developed PE had decrease in 15-epi-LXA4 levels compared to those without PE (942 pg/mL [348.3-1810.3] vs 1758.2 pg/mL [905.4-6638.5]; p = 0.129). CONCLUSION: Daily LDA administration increases 15-epi-LXA4 levels in high-risk pregnancies for PE. In LDA group, pregnancies complicated by PE have lower levels of 15-epi-LXA4 compared to pregnancies without PE.

Operating Room Guide for Confirmed or Suspected COVID-19 Pregnant Patients Requiring Cesarean Delivery.

We sought to provide a clinical practice protocol for our labor and delivery (L&D) unit, to care for confirmed or suspected COVID-19 patients requiring cesarean delivery. A multidisciplinary team approach guidance was designed to simplify and streamline the flow and care of patient with confirmed or suspected COVID-19 requiring cesarean delivery. A protocol was designed to improve staff readiness, minimize risks, and streamline care processes. This is a suggested protocol which may not be applicable to all health care settings but can be adapted to local resources and limitations of individual L&D units. Guidance and information are changing rapidly; therefore, we recommend continuing to update the protocol as needed. KEY POINTS: · Cesarean delivery for confirmed or suspected novel coronavirus disease 2019 (COVID-19) patients. · Team-based approach for streamline care. · Labor and delivery protocols for COVID-19 positive patients.

A New Method for Workplace Monitoring of Airborne Diacetyl and 2,3-Pentanedione Using Thermal Desorption Tubes and Gas Chromatography-Mass Spectrometry.

Diacetyl is a potentially harmful chemical that is used as an artificial flavouring in the food industry and may also be generated during processing of some natural products including coffee. In Europe, an 8-h time weighted average occupational exposure limit (TWA-OEL) of 20 ppb has been adopted for diacetyl, together with a short-term exposure limit (STEL) of 100 ppb. A sensitive new measurement method for diacetyl, and the related compound 2,3-pentanedione has been developed and evaluated. The new method uses Tenax TA sorbent tubes as the sampling media with analysis by thermal desorption (TD) and gas chromatography-mass spectrometry (GC-MS). The sample tubes are suitable for both active (pumped) and passive (diffusive) sampling. Diacetyl is stable on the sample tubes for at least 3 months but 2,3-pentanedione requires analysis within a month. Sample recovery is unaffected by changes in relative humidity and the presence of acetic acid. For short-term sampling, active sampling is recommended. The safe sampling volume for diacetyl is 3 litres which, at a flow rate of 100 ml min-1, equates to a maximum recommended sampling time of 30 min. For long-term samples, in particular collection of personal samples, passive sampling is recommended. Diffusive uptake rates have been determined for both diacetyl and 2,3-pentanedione on Tenax TA tubes fitted with standard diffusion heads over sampling periods of 1 to 8 h. Analytical limits of detection are approximately 0.2 ng for diacetyl and 0.1 ng for 2,3-pentanedione. These values equate to airborne concentrations of around 0.04 ppb of diacetyl and 0.02 ppb of 2,3-pentanedione for a 1.5-litre active sample and 0.3 ppb of diacetyl and 0.1 ppb of 2,3-pentanedione for an 8-h passive sample. In the case of passive sampling, this limit of detection is less than 1/50th of the new European TWA-OEL for diacetyl of 20 ppb. The method can also be used to identify the presence of other volatile organic compounds at sub-ppm concentrations.

Obesity and laboratory aspirin resistance in high-risk pregnant women treated with low-dose aspirin.

BACKGROUND: Low-dose aspirin is used for preeclampsia prevention in high-risk women, but the precise mechanism and optimal dose are unknown. Evidence suggests that an imbalance in prostacyclin and thromboxane A2 (TXA2) plays a key role in the pathogenesis of preeclampsia. Aspirin has a dose-dependent effect blocking production of TXA2, a potent stimulator of platelet aggregation and promoter of vasoconstriction. Incomplete inhibition of platelet aggregation, designated aspirin resistance, can be reduced by increasing the aspirin dose. Evidence in the nonobstetric literature suggests that aspirin resistance may be more common among patients with a high body mass index. OBJECTIVE: To investigate the association of obesity on platelet-derived thromboxane inhibition in high-risk women treated with low-dose aspirin. MATERIALS AND METHODS: This was a secondary analysis of a prospective multi-centered study investigating the effect of low-dose aspirin (60-mg) administration in women at high risk for preeclampsia. Maternal serum TXB2 (an indirect measure of TxA2) levels were drawn at 3 time points: randomization (13-26 weeks' gestation), second trimester (at least 2 weeks after randomization and 24-28 weeks' gestation), and third trimester (34-38 weeks' gestation). Patients were included in the analysis if a TXB2 level was recorded at randomization and at least 1 time point thereafter. Patients were stratified by body mass index category and treatment arm. Median TXB2 levels were calculated at each time point, as well as rates of complete TXB2 inhibition (<0.01 ng/mL). A multivariate logistic regression analysis was performed to generate odds ratios (OR) for complete TXB2 inhibition by body mass index category, adjusting for maternal age, race, high-risk group at randomization, nulliparity, and rate of randomization less than 16 weeks' gestation. RESULTS: A total of 1002 patients were included in the analysis, 496 (49.5%) and 506 (50.5%) in the low-dose aspirin and placebo groups respectively. There were substantial decreases in TXB2 levels among low-dose aspirin-treated women in all body mass index categories. In contrast, women assigned to placebo did not show a marked decrease in TXB2 levels after randomization, and obese women had higher median TXB2 levels in both the second (16.5, interquartile range [IQR] 8.0-31.8 vs 14.0, IQR 6.9-26.7, ng/mL; P = .032) and third (15.7, IQR 7.6-28.5 vs 11.9, IQR 4.6-25.9, ng/mL; P = .043) trimesters. When comparing among stratified body mass index low-dose aspirin groups, women with class III obesity had the lowest odds of undetectable TXB2 levels in the second trimester (adjusted odds ratio [aOR], 0.33; 95% confidence interval [CI], 0.15-0.72) and third trimester (aOR, 0.30; 95% CI, 0.11-0.78) as well as at both time points (aOR, 0.09; 95% CI, 0.02-0.41). CONCLUSION: High-risk obese women receiving low-dose aspirin for the prevention of preeclampsia have lower rates of complete inhibition of TXB2. These data suggest that an increase in aspirin dosing or frequency may be necessary in this population.

Evaluation of the stability of a mixture of volatile organic compounds on sorbents for the determination of emissions from indoor materials and products using thermal desorption/gas chromatography/mass spectrometry.

The standard method for the determination of volatile organic compounds (VOCs) in indoor and test chamber air (ISO 16000-6:2011) specifies sampling onto the sorbent Tenax TA followed by analysis using thermal desorption/gas chromatography/mass spectrometry (TD/GC/MS). The informative Annex D to the standard suggests the use of multi-sorbent samplers to extend the volatility range of compounds which can be determined. The aim of this study was to investigate the storage performance of Tenax TA and two multi-sorbent tubes loaded with a mixture of nine VOCs of relevance for material emissions testing. The sorbent combinations tested were quartz wool/Tenax TA/Carbograph™ 5TD and quartz wool/Tenax TA/Carbopack™ X. A range of loading levels, loading conditions (humidities and air volume), storage times (1-4 weeks) and storage conditions (refrigerated and ambient) were investigated. Longer term storage trials (up to 1 year) were conducted with Tenax TA tubes to evaluate the stability of tubes used for proficiency testing (PT) of material emissions analyses. The storage performance of the multi-sorbent tubes tested was found to be equal to that for Tenax TA, with recoveries after 4 weeks storage of within about 10% of the amounts loaded. No consistent differences in recoveries were found for the different loading or storage conditions. The longer term storage trials also showed good recovery for these compounds, although two other compounds, hexanal and BHT, were found to be unstable when stored on Tenax TA. The results of this study provide confidence in the stability of nine analytes for up to 4 weeks on two multi-sorbent tubes for material emissions testing and the same compounds loaded on Tenax TA sorbent for a recently introduced PT scheme for material emissions testing.

Assessing and controlling risks from the emission of organic chemicals from construction products into indoor environments.

Construction products can be a significant source of indoor pollutants, including volatile organic compounds that may be a risk to the health and well-being of building occupants. There are currently a number of schemes for the labelling of products according to their potential to emit organic compounds. Assessment of the complex mixtures of compounds that may be released has mandated the development of test methods that allow the determination of the concentrations of the chemicals released from products in controlled test chamber environments. In response to concerns about the financial burden faced by manufacturers required to test products according to the various different labelling schemes currently in existence, the European Commission has investigated the scope for greater harmonisation. This initiative has sought to harmonise the process for the assessment of emissions data, complementing work led by the European standards organisation focussed on harmonising the test chamber procedures. The current labelling schemes have a range of requirements with respect to the number of chemicals to be quantified. A comparison of 13 schemes worldwide has identified 15 lists of target compounds, with a total of 611 chemicals occurring on at least one of the target lists. While harmonisation may clarify and perhaps simplify these requirements, at least in Europe, it can be expected that future changes to product formulations, the introduction of new products and our increasing knowledge about the potential risks to health, will require continued development of new and improved measurement techniques. There is, therefore, a particular challenge for analytical chemists to ensure the efficient provision of high quality emissions data and thereby ultimately enable effective control of risks to human health through the prevention or reduction of indoor air pollution.

Invasive Haemophilus influenzae disease caused by non-type b strains in Northwestern Ontario, Canada, 2002-2008.

A high incidence of invasive non-type b Haemophilus influenzae disease was found in Northwestern Ontario, Canada; H. influenzae type a was the most prevalent serotype (42%). Clinical and demographic analyses indicate that aboriginal children aged <5 years and adults with predisposing medical conditions are the most affected by invasive H. influenzae disease in the post-H. influenzae vaccine era.

Exposure to air pollutants in English homes.

BRE has conducted a national representative survey of air pollutants in 876 homes in England, designed to increase knowledge of baseline pollutant levels and factors associated with high concentrations. Homes were monitored for carbon monoxide (CO), nitrogen dioxide (NO(2)), formaldehyde and volatile organic compounds (VOCs). In the majority of the homes, concentrations of the measured pollutants were low. However, some homes have concentrations that would suggest a need for precautionary mitigation. Those factors that are most likely to lead to exposures of concern in homes are identified as gas cooking (for CO and NO(2)), the use of unflued appliances for heating (for CO and NO(2)), emissions from materials in new homes (for total VOC (TVOC) and formaldehyde), and painting and decorating, with a significant increase in risk suspected to exist where there is not a place to store materials away from the living space (for TVOC). It is noteworthy that seasonal effects on CO and NO(2) were largely due to indoor sources. This would need to be considered when interpreting time series studies of the effect of outdoor air pollution on health. It is also of some significance that the critical factors are related much more to sources than to ventilation: source control is therefore, as would be expected, the most appropriate approach to reducing the risk of hazardous exposure to air pollutants in homes.