The effect of ozone short-term exposure on flow-mediated dilation: Using data before and after COVID-19 lockdown in Shanghai.

BACKGROUND: Short-term ambient ozone exposure has been shown to have an adverse impact on endothelial function, contributing to major cardiovascular diseases and premature death. However, only limited studies have focused on the impact of short-term ozone exposure on Flow-mediated Dilation (FMD), and their results have been inconsistent. The current study aims to explore the relationship between short-term ambient ozone exposure and FMD. In addition, the study aims to investigate how lockdown measures for COVID-19 may influence ozone concentration in the atmosphere. METHODS: Participants were recruited from a hospital in Shanghai from December 2020 to August 2022. Individuals' ozone exposure was determined using residential addresses. A distributed lag nonlinear model was adopted to assess the exposure-response relationship between short-term ozone exposure and FMD. A comparison was made between ambient ozone concentration and FMD data collected before and after Shanghai's lockdown in 2022. RESULTS: When ozone concentration was between 150 and 200 µg/m3, there was a significant reduction in FMD with a 2-day lag. Elderly individuals (age ≥ 65), females, non-drinkers, and non-smokers were found to be more susceptible to high concentrations of ozone exposure. The lockdown did elevate ambient ozone concentration compared to the same period previously. INTERPRETATION: This study proposes that an ambient ozone concentration of 150-200 µg/m3 is harmful to endothelial function, and that a reduction in human activity during lockdown increased the concentration, which in turn reduced FMD. However, the underlying mechanism requires further research.

Measurement of airborne particle emission during surgical and percutaneous dilatational tracheostomy COVID-19 adapted procedures in a swine model: Experimental report and review of literature.

INTRODUCTION: Surgical tracheostomy (ST) and Percutaneous dilatational tracheostomy (PDT) are classified as high-risk aerosol-generating procedures and might lead to healthcare workers (HCW) infection. Albeit the COVID-19 strain slightly released since the vaccination era, preventing HCW from infection remains a major economical and medical concern. To date, there is no study monitoring particle emissions during ST and PDT in a clinical setting. The aim of this study was to monitor particle emissions during ST and PDT in a swine model. METHODS: A randomized animal study on swine model with induced acute respiratory distress syndrome (ARDS) was conducted. A dedicated room with controlled airflow was used to standardize the measurements obtained using an airborne optical particle counter. 6 ST and 6 PDT were performed in 12 pigs. Airborne particles (diameter of 0.5 to 3 µm) were continuously measured; video and audio data were recorded. The emission of particles was considered as significant if the number of particles increased beyond the normal variations of baseline particle contamination determinations in the room. These significant emissions were interpreted in the light of video and audio recordings. Duration of procedures, number of expiratory pauses, technical errors and adverse events were also analyzed. RESULTS: 10 procedures (5 ST and 5 PDT) were fully analyzable. There was no systematic aerosolization during procedures. However, in 1/5 ST and 4/5 PDT, minor leaks and some adverse events (cuff perforation in 1 ST and 1 PDT) occurred. Human factors were responsible for 1 aerosolization during 1 PDT procedure. ST duration was significantly shorter than PDT (8.6 ± 1.3 vs 15.6 ± 1.9 minutes) and required less expiratory pauses (1 vs 6.8 ± 1.2). CONCLUSIONS: COVID-19 adaptations allow preventing for major aerosol leaks for both ST and PDT, contributing to preserving healthcare workers during COVID-19 outbreak, but failed to achieve a perfectly airtight procedure. However, with COVID-19 adaptations, PDT required more expiratory pauses and more time than ST. Human factors and adverse events may lead to aerosolization and might be more frequent in PDT.

Lower brachial artery flow-mediated dilation is associated with a worse prognosis and more lung parenchymal involvement in Covid-19: Prospective observational study.

Severe acute respiratory syndrome coronavirus-2 is a highly infectious pathogenic coronavirus, which has appeared toward the end of 2019. The virus seen all over the world caused a pandemic of an acute respiratory disease named coronavirus disease 2019 (Covid-19). It has been shown that the virus that uses angiotensin-converting enzyme 2 receptors is causing endothelial dysfunction resulting in vascular inflammation and coagulopathy. It is possible to assess endothelial dysfunction by the flow-mediated dilatation (FMD) technique. Our study aimed to demonstrate the effect of endothelial dysfunction assessed using the FMD on prognosis and mortality in the patients hospitalized with the diagnosis of Covid-19. In this prospective observational study, endothelial functions of 94 patients hospitalized due to the Covid-19 in the ward or intensive care unit (ICU) were evaluated by FMD. The relationship among endothelial dysfunction and prognosis of disease, biochemical parameters, lung involvement, and mortality was investigated. We found that the FMD% values of the Covid-19 ICU patients compared to those followed up in the ward (2.66 ± 0.62 vs. 5.23 ± 1.46/P < .001) and those who died due to Covid-19 compared to those who were discharged alive (2.57 ± 0.22 vs. 4.66 ± 1.7/P < .001) were significantly lower. There were moderate negative correlation between FMD% and peak values of D-dimer (r = -0.52, P < .001), troponin (r = -0.45, P < .001), ferritin (r = -0.47, P < .001), lactate dehydrogenase (r = -0.49, P < .001), and white blood cells count (r = -0.23, P = .024). Lower FMD% was associated with higher lung parenchymal involvement (P < .001). The optimum cutoff point of FMD in predicting mortality was found to be 3.135% (sensitivity: 1, selectivity: 0.70). According to our results, lower FMD% was associated with higher lung parenchyma involvement, ICU admission, and mortality rate in Covid-19 patients. The best cutoff point for predicting mortality of FMD was 3.135%. Nevertheless, largescale, multicenter studies are needed to evaluate lower FMD values as a risk factor for mortality in Covid-19.

Mild coronary artery dilatation developed in some children with mild COVID-19 but completely regressed within 3 months.

AIM: We studied the incidence and time course of any coronary artery changes in children up to 2 years of age who were hospitalised with mild COVID-19. METHODS: This was a single-centre prospective study of 29 children (19 males) with a median age of 3 months and interquartile range (IQR) of 1.6-4.3 months. They were admitted to a Greek University hospital for mild COVID-19 from 1 March to 30 December 2021. Three echocardiographic evaluations were performed at a median (IQR) of 19 (16-24) days, 82 (75-89) days and 172 (163-197) after the first symptoms. The prevalence of coronary artery dilation, regression, and changes was documented. RESULTS: Coronary artery dilation was present in 3 (10.3%) cases at the first evaluation, with complete regression at the second. Regression was observed in 18/24 (75%) cases with follow-up data and 9 (31%) demonstrated significant z-score changes of >2. Coronary artery changes in any segment at any time were documented in 18/29 (62%) of the patients. CONCLUSION: Cases of transient and very mild coronary artery dilatation following mild COVID-19 completely regressed within 3 months. Large-scale studies are needed to document the extent and time course of coronary artery dilation following paediatric COVID-19.

Evaluation of Endothelial Dysfunction in COVID-19 With Flow-Mediated Dilatation. / Avaliação da Disfunção Endotelial em Casos de COVID-19 com Dilatação Fluxo-Mediada.

BACKGROUND: Inflammation is known to play a crucial role in many diseases, including COVID-19. OBJECTIVE: Using flow-mediated dilatation (FMD), we aimed to assess the effects of inflammation on endothelial function in COVID-19 patients. METHODS: This study was conducted with a total of 161 subjects, of whom 80 were diagnosed with COVID-19 within the last six months (comprising 48 women and 32 men with a mean age of 32.10 ± 5.87 years) and 81 were healthy controls (comprising 45 women and 36 men with a mean age of 30.51 ± 7.33 years). We analyzed the findings of transthoracic echocardiography and FMD in all subjects. All results were considered statistically significant at the level of p < 0.05. RESULTS: The echocardiography and FMD of the COVID-19 group were performed 35 days (range: 25-178) after diagnosis. There was no statistically significant difference in echocardiographic parameters. Differently, FMD (%) was significantly higher in the control group (9.52 ± 5.98 vs. 12.01 ± 6.18, p=0.01). In multivariate analysis with the forward stepwise model, FMD was significantly different in the control group compared to the COVID-19 group (1.086 (1.026 - 1.149), p=0.04). A Spearman's correlation test indicated that FMD (r=0.27, p=0.006) had a weak positive correlation with the presence of COVID-19. CONCLUSION: Our findings point to COVID-19-induced endothelial dysfunction, as assessed by FMD, in the early recovery phase.

FUNDAMENTO: Sabe-se que a inflamação desempenha um papel crucial em muitas doenças, incluindo a COVID-19. OBJETIVO: Utilizando a dilatação fluxo-mediada (DFM), objetivou-se avaliar os efeitos da inflamação na função endotelial de pacientes com COVID-19. MÉTODOS: Este estudo foi realizado com um total de 161 indivíduos, dos quais 80 foram diagnosticados com COVID-19 nos últimos seis meses (48 mulheres e 32 homens com idade média de 32,10±5,87 anos) e 81 eram controles saudáveis (45 mulheres e 36 homens com idade média de 30,51±7,33 anos). Os achados do ecocardiograma transtorácico e da DFM foram analisados em todos os indivíduos. Resultados com p<0,05 foram considerados estatisticamente significantes. RESULTADOS: O ecocardiograma e a DFM do grupo COVID-19 foram realizados 35 dias (intervalo: 25­178) após o diagnóstico. Não houve diferença estatisticamente significativa nos parâmetros ecocardiográficos. Em contraste, a DFM (%) foi significativamente maior no grupo controle (9,52±5,98 versus 12,01±6,18; p=0,01). Na análise multivariada com o modelo stepwise progressivo, a DFM foi significativamente diferente no grupo controle em relação ao grupo COVID-19 (1,086 (1,026­1,149), p=0,04). O teste de correlação de Spearman indicou que a DFM (r=0,27; p=0,006) apresentou correlação positiva fraca com a presença de COVID-19. CONCLUSÃO: Os achados deste estudo apontam para disfunção endotelial induzida por COVID-19, avaliada por DFM, na fase inicial de recuperação.

Percutaneous dilatational tracheostomy with single use bronchoscopes versus reusable bronchoscopes - a prospective randomized trial (TraSUB).

BACKGROUND: Apart from conventional reusable bronchoscopes, single-use bronchoscopes (SUB) were recently introduced. Data suggest that SUB might prevent from the risk of cross contamination (i.e. multiresistant pathogens, SARS CoV-2) and save costs. We aimed to investigate visualization, ventilation, handling characteristics, changes in patients' gas exchange, and costs associated with both types of bronchoscopes during percutaneous dilatational tracheostomy (PDT). METHODS: In this prospective, randomized, noninferiority study, 46 patients undergoing PDT were randomized 1:1 to PDT with SUB (Ambu aScope) or reusable bronchoscopes (CONV, Olympus BF-P60). Visualization of tracheal structures rated on 4-point Likert scales was the primary end-point. Furthermore, quality of ventilation, device handling characteristics, changes in the patients' gas exchange, pH values, and costs were assessed. RESULTS: Noninferiority for visualization (the primary endpoint) was demonstrated for the SUB group. Mean visualization scores (lower values better) were 4.1 (95% confidence intervals: 3.9;4.3) for SUB vs. 4.1 (4.0;4.2) for CONV. Noninferiority of ventilation (estimated by minute volume and SpO2) during the procedure could be shown as well. Mean score was 2.6 (2.0;3.1) for SUB vs. 2.4 (2.1;2.7) for CONV (lower values better). No significant differences regarding handling (SUB: 1.2 (1.0;1.4), CONV: 1.3 (1.1;1.6)), blood gas analyses and respiratory variables were found. Cost analysis in our institution revealed 93 € per conventional bronchoscopy versus 232.50 € with SUB, not considering an estimate for possible infection due to cross-contamination with the reusable device. CONCLUSION: In our study, visualization and overall performance of the SUB during PDT were noninferior to reusable bronchoscopes. Therefore, PDT with SUB is feasible and should be considered if favored by individual institution's cost analysis. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03952247 . Submitted for registration on 28/04/2019 and first posted on 16/05/2019.

Carotid intima-media thickness and flow-mediated dilation do not predict acute in-hospital outcomes in patients hospitalized with COVID-19.

Studies have suggested a potential role of endothelial dysfunction and atherosclerosis in the pathophysiology of COVID-19. Herein, we tested whether brachial flow-mediated dilation (FMD) and carotid intima-media thickness (cIMT) measured upon hospital admission are associated with acute in-hospital outcomes in patients hospitalized with COVID-19. A total of 211 patients hospitalized with COVID-19 were submitted to assessments of FMD and mean and maximum cIMT (cIMTmean and cIMTmax) within the first 72 h of hospital admission. Study primary outcome was a composite of intensive care unit admission, mechanical ventilation, or death during the hospitalization. These outcomes were also considered independently. Thrombotic events were included as a secondary outcome. Odds ratios (ORs) and confidence intervals (CIs) were calculated using unadjusted and adjusted multivariable logistic regression models. Eighty-eight (42%) participants demonstrated at least one of the composite outcomes. cIMTmean and cIMTmax were predictors of mortality and thrombotic events in the univariate analysis (cIMTmean and mortality: unadjusted OR 12.71 [95% CI 1.71-94.48]; P = 0.014; cIMTmean and thrombotic events: unadjusted OR 11.94 [95% CI 1.64-86.79]; P = 0.015; cIMTmax and mortality: unadjusted OR 8.47 [95% CI 1.41-51.05]; P = 0.021; cIMTmax and thrombotic events: unadjusted OR 12.19 [95% CI 2.03-73.09]; P = 0.007). However, these associations were no longer present after adjustment for potential confounders (P > 0.05). In addition, FMD% was not associated with any outcome. In conclusion, cIMT and FMD are not independent predictors of clinical outcomes in patients hospitalized with COVID-19. These results suggest that subclinical atherosclerosis and endothelial dysfunction may not be the main drivers of COVID-19 complications in patients hospitalized with COVID-19.NEW & NOTEWORTHY Studies have suggested a role of endothelial dysfunction and atherosclerosis in COVID-19 pathophysiology. In this prospective cohort study, we assessed the prognostic value of carotid intima-media thickness (IMT) and flow-mediated dilation (FMD) in patients with COVID-19. Carotid IMT and FMD were not independent predictors of major outcomes. These results suggest that other risk factors may be the main drivers of clinical outcomes in patients with COVID-19.

A 2-Month-Old with Kawasaki Disease with Coronary Artery Dilation in the Pre-COVID-19 Era.

BACKGROUND Kawasaki disease (KD) is an acute inflammatory vasculitis, which occurs mostly in childhood, predominantly between the ages of 6 months and 5 years. The incidence of coronary artery abnormalities associated with KD has decreased from 25% to 4% as a result of timely diagnosis and treatment with intravenous immunoglobulin (IVIG). Infants ≤6 months of age are the most likely to develop prolonged fever without the other clinical criteria for KD, and diagnosis can sometimes be challenging or delayed. They are therefore at particularly high risk of developing coronary artery abnormalities. CASE REPORT A 2-month-old male infant with no significant medical history initially presented with a history of nasal congestion, right conjunctivitis, red lips, and 1 loose stool in the pre-COVID-19 era. He was diagnosed with otitis media and was started on oral amoxicillin. By day 7 of fever, he had developed symptoms and signs and laboratory findings consistent with Kawasaki disease, which is rare in this age group. His echocardiogram showed dilated proximal left anterior descending and right coronary arteries. He was successfully treated, and his most recent echocardiogram, performed 17 months after his treatment, showed remarkable improvement in the coronary arteries. CONCLUSIONS Kawasaki disease in children less than 6 months of age is still rare, and the presentation can sometimes make the diagnosis somewhat challenging. Increased clinical suspicion is required for recognition in the youngest patients, as they are more likely to present with few features of KD. Early diagnosis and treatment are needed to prevent or minimize the risk of significant coronary artery abnormalities.

Percutaneous Dilational Tracheostomy for Coronavirus Disease 2019 Patients Requiring Mechanical Ventilation.

OBJECTIVES: To assess the impact of percutaneous dilational tracheostomy in coronavirus disease 2019 patients requiring mechanical ventilation and the risk for healthcare providers. DESIGN: Prospective cohort study; patients were enrolled between March 11, and April 29, 2020. The date of final follow-up was July 30, 2020. We used a propensity score matching approach to compare outcomes. Study outcomes were formulated before data collection and analysis. SETTING: Critical care units at two large metropolitan hospitals in New York City. PATIENTS: Five-hundred forty-one patients with confirmed severe coronavirus disease 2019 respiratory failure requiring mechanical ventilation. INTERVENTIONS: Bedside percutaneous dilational tracheostomy with modified visualization and ventilation. MEASUREMENTS AND MAIN RESULTS: Required time for discontinuation off mechanical ventilation, total length of hospitalization, and overall patient survival. Of the 541 patients, 394 patients were eligible for a tracheostomy. One-hundred sixteen were early percutaneous dilational tracheostomies with median time of 9 days after initiation of mechanical ventilation (interquartile range, 7-12 d), whereas 89 were late percutaneous dilational tracheostomies with a median time of 19 days after initiation of mechanical ventilation (interquartile range, 16-24 d). Compared with patients with no tracheostomy, patients with an early percutaneous dilational tracheostomy had a higher probability of discontinuation from mechanical ventilation (absolute difference, 30%; p < 0.001; hazard ratio for successful discontinuation, 2.8; 95% CI, 1.34-5.84; p = 0.006) and a lower mortality (absolute difference, 34%, p < 0.001; hazard ratio for death, 0.11; 95% CI, 0.06-0.22; p < 0.001). Compared with patients with late percutaneous dilational tracheostomy, patients with early percutaneous dilational tracheostomy had higher discontinuation rates from mechanical ventilation (absolute difference 7%; p < 0.35; hazard ratio for successful discontinuation, 1.53; 95% CI, 1.01-2.3; p = 0.04) and had a shorter median duration of mechanical ventilation in survivors (absolute difference, -15 d; p < 0.001). None of the healthcare providers who performed all the percutaneous dilational tracheostomies procedures had clinical symptoms or any positive laboratory test for severe acute respiratory syndrome coronavirus 2 infection. CONCLUSIONS: In coronavirus disease 2019 patients on mechanical ventilation, an early modified percutaneous dilational tracheostomy was safe for patients and healthcare providers and associated with improved clinical outcomes.

Mifepristone prior to osmotic dilators for dilation and evacuation cervical preparation: A randomized, double-blind, placebo-controlled pilot study.

OBJECTIVES: To evaluate mifepristone impact on osmotic dilator placement and procedural outcomes when given 18 to 24 hours before dilator placement for dilation and evacuation (D&E) at 18 weeks 0 days to 23 weeks 6 days gestation. STUDY DESIGN: We performed a randomized, double-blind, placebo-controlled trial from April 2019 through February 2021, enrolling participants undergoing osmotic dilator (Dilapan) placement for a planned, next-day D&E. Participants took mifepristone 200 mg or placebo orally 18 to 24 hours before dilator placement. We used a gestational age-based protocol for minimum number of dilators. Our primary outcome was the proportion of participants for whom 2 or more additional dilators could be placed compared to the minimum gestational age-based standard. We secondarily evaluated cervical dilation after dilator removal in the operating room, subjective procedure ease, and complication rates (cervical laceration, uterine perforation, blood transfusion, infection, hospitalization, or extramural delivery). RESULTS: Of the planned 66 participants, we enrolled 44 (stopped due to coronavirus disease 2019-related obstacles), and 41 (19 mifepristone; 22 placebo) completed the study. We placed 2 or more additional dilators compared to standard in 7 (36.8%) and 3 (13.6%) participants after mifepristone and placebo, respectively (p = 0.14). We measured greater median initial cervical dilation in the mifepristone (3.2 cm[2.6-3.6]) compared to placebo (2.6 cm[2.2-3.0]) group, p = 0.03. Surgeon's perception of procedure being "easy" (8/19[42.1] vs 9/22[40.9], respectively, p = 1.00) and complication rate (3/19[15.8%] vs 3/22[13.6], respectively, p = 1.00) did not differ. CONCLUSION: Our underpowered study did not demonstrate a difference in cervical dilator placement, but mifepristone 18 to 24 hours prior to dilators increases cervical dilation without increasing complications. IMPLICATIONS: Mifepristone 18 to 24 hours prior to cervical dilator placement may be a useful adjunct to cervical dilators based on increased cervical dilation at time of procedure; however, logistical barriers, such as an additional visit, may preclude routine adoption without definite clinical benefit.

Persistent Right Ventricle Dilatation in SARS-CoV-2-Related Acute Respiratory Distress Syndrome on Extracorporeal Membrane Oxygenation Support.

OBJECTIVES: Venovenous extracorporeal membrane oxygenation (ECMO) support may be considered in experienced centers for patients with acute respiratory distress syndrome (ARDS) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection refractory to conventional treatment. In ECMO patients, echocardiography has emerged as a clinical tool for implantation and clinical management; but to date, little data are available on COVID-related ARDS patients requiring ECMO. The authors assessed the incidence of right ventricular dilatation and dysfunction (RvDys) in patients with COVID-related ARDS requiring ECMO. DESIGN: Single-center investigation. SETTING: Intensive care unit (ICU). PARTICIPANTS: A total of 35 patients with COVID-related ARDS requiring ECMO, consecutively admitted to the ICU (March 1, 2020, to February 28, 2021). INTERVENTIONS: Serial echocardiographic examinations. RvDys was defined as RV end-diastolic area/LV end-diastolic area >0.6 and tricuspid annular plane excursion <15 mm. MEASUREMENTS AND MAIN RESULTS: The incidence of RvDys was 15/35 (42%). RvDys patients underwent ECMO support after a longer period of mechanical ventilation (p = 0.006) and exhibited a higher mortality rate (p = 0.024) than those without RvDys. In nonsurvivors, RvDys was observed in all patients (n = nine) who died with unfavorable progression of COVID-related ARDS. In survivors, weaned from ECMO, a significant reduction in systolic pulmonary arterial pressures was detectable. CONCLUSIONS: According to the authors' data, in COVID-related ARDS requiring ECMO support, RvDys is common, associated with increased ICU mortality. Overall, the data underscored the clinical role of echocardiography in COVID-related ARDS supported by venovenous ECMO, because serial echocardiographic assessments (especially focused on RV changes) are able to reflect pulmonary COVID disease severity.

COVID 19 disease independently predicted endothelial dysfunction measured by flow-mediated dilatation.

The systemic effects of COVID-19 disease are still largely uncertain and needs to be scrutinized with further trials. Endothelial dysfunction (ED) is responsible for the majority of adverse cardiovascular events. Flow-mediated dilation (FMD) is easily obtainable method to assess ED accurately. It is aimed to evaluate ED by measuring FMD following COVID-19 disease. Patients diagnosed with COVID-19 disease were recruited to the hospital two month after the discharge. Sex and age-matched healthy subjects were determined as the control group. Blood samples and FMD measurements were obtained from each participant. All subjects were divided into two groups according to the presence of ED determined by FMD measurements. These two groups were compared in terms of demographic features and the presence of recovered COVID-19 disease. A total of 92 subjects consisting of 59 without ED and 33 with ED were included in the study. ED (+) group was older (p = 0.015) and more likely to have hypertension (p = 0.044) and COVID-19 rate was higher in ED (+) group (p = 0.009). While neutrophil count (p = 0.047) and CRP (p = 0.036) were higher, eGFR (p = 0.044) was lower in ED (+) group. In the backward multivariable regression analysis, COVID-19 disease [OR = 3.611, 95% CI 1.069-12.198, p = 0.039] and BMI [OR = 1.122, 95% CI 1.023-1.231, p = 0.015] were independent predictors of ED. COVID-19 disease may cause ED which is the major underlying factor of cardiovascular diseases. Furthermore, COVID-19 disease may deteriorate the existing cardiovascular disease course. Detecting ED in the early phase or preventing by new treatment modalities may improve short and long-term outcome.

Ephemeral history of the three-bladed tracheostomy dilator.

Tracheostomy remains a topical surgical procedure. The history of tracheostomy is marked by the development of various instruments, including the three-bladed tracheostomy dilator from the middle of the 19th century. The purpose of this historical note is to recall the use of this unusual instrument.