Decrease In Saturation Research Articles

Early diagnosis of occult pulmonary embolism secondary to lower limb fractures: summary of 18 cases.

Pulmonary thromboembolism is a severe but probably underdiagnosed disorder. Patients with lower limb fractures are at high risk for pulmonary thromboembolism. This study aimed to demonstrate the early identification strategies for occult pulmonary thromboembolism. From January to December 2022, 18 patients diagnosed with pulmonary thromboembolism were reviewed for this study. Data on patients' demographics, laboratory test results, and radiographic findings were collected. Finally, the data was analyzed. Eighteen patients with lower limb fractures were included in this study. All of them present different symptoms, including 12 cases (12/18, 66%) of unexplained decrease in oxygen saturation; 16 patients had deep vein thrombosis in the lower limbs, with nine cases involving proximal veins and seven involving distal veins. One patient had an antithrombin III level of 35%. Thirteen cases were diagnosed with pulmonary embolism using CT pulmonary angiography. Four patients had pulmonary embolisms incidentally detected during coronary CT angiography, and one patient during aortic CT angiography. Patients with lower limb fractures showing chest tightness and unexplained decrease in finger pulse oxygen levels should be assessed for pulmonary thromboembolism. Simultaneously, selecting appropriate diagnostic tools is essential to guaranteeing quick and accurate diagnosis.

Development of technology for obtaining asphalt concrete mixture using oil sludge as an additive

Oil sludge is similar in composition to the composition of bitumen, which is one of the important components of asphalt concrete mixture. Therefore, oil waste can be used in the production of asphalt concrete, both as an organic binder to strengthen local soils and as a binder to produce organomineral mixtures. The use of oil sludge in road construction helps preserve natural resources, improve the environmental situation, and reduce the cost of building materials. In this work, physical and mechanical properties of asphalt concrete mixture of grade I type B were researched. To improve the performance characteristics of asphalt concrete oil sludge from oil company Zhaik Munay LLP (Uralsk) was used as an additive. Oil sludge was added to the asphalt concrete mixture in amounts of 5, 10 and 15%. When using 5% oil sludge, no significant changes in the properties of asphalt concrete are observed. An addition of 15% of oil went to the reduction of maximum efficiency during compression (0.03% by volume) and shear resistance by the efficiency of internal friction coefficient (0.01% by volume). The optimal amount is to use 10% oil sludge, at the same time, the compressive strength increases by 0.07% by volume, water resistance increases (0.02% by volume), water saturation decreases by 0.28% by volume, which has a positive effect on the quality of asphalt concrete. The properties of asphalt concrete before and after adding oil sludge were studied: compressive strength, water resistance, water saturation, shear resistance. It was concluded that it is advisable to use oil sludge as an additive. A technology for producing asphalt concrete mixture using oil sludge has been developed, which allows reducing its cost.

Steroid prescribing practices for mildly symptomatic and asymptomatic COVID-19 patients, among doctors of selected Sri Lankan hospitals

Introduction: Effects of infection by SARS-COV-2 virus (COVID-19) range from asymptomatic infection to respiratory failure with multi-organ dysfunction. Steroids are indicated in patients with severe pneumonia, who require oxygen supplementation. There is evidence of harm if steroids are given for asymptomatic or mildly symptomatic patients.Objectives: This study assesses the steroid prescribing practices among Sri Lankan doctors for mildly symptomatic and asymptomatic COVID-19 patients.Methodology: This clinical survey was conducted during 20/11/2021 to 15/03/2022 using an electronic questionnaire, sent to doctors in 16 hospitals, representing all provinces of Sri Lanka. Doctors who have not treated nor advised patients with COVID-19 were excluded.Results: Hundred and thirty-five participants were incorporated into the study. The mean age was 33.7 years (SD=7.82). The majority did not prescribe steroids routinely for asymptomatic (n=132, 97.8%) and mildly symptomatic (n=124, 91.9%) COVID-19. Dexamethasone was the most prescribed steroid. Doctors who treated COVID-19 patients in the private sector were more likely to prescribe steroids for mild symptoms (p=0.016). The majority (n=101, 81.5%) identified a decrease of oxygen saturation to below 94% on room air as an indication to start steroids.Conclusions: Most of the study participants adhered to the recommended guidelines and refrained from prescribing steroids in mildly symptomatic and asymptomatic COVID-19 patients.

Application of a New Type of Protective Sputum Suction Device in Clinic against Cross-Infection between Medical Staff and Patients.

To explore the clinical application of a new type of protective sputum suction device (PSSD) in patients with tracheotomy or tracheal intubation and to evaluate the protective effect of PSSD against cross-infection between medical staffs and patients. A novel PSSD was designed which can assist closed sputum suction operation without disconnecting the ventilator. 32 patients with tracheotomy were included to study the protective effect and safety of this device. Patients' vital signs including heart rate, respiratory rate, mean arterial pressure, and blood oxygen saturation were recorded to compare the influence of open suction and closed suction (performed with this novel device). To verify the antisplash effect of this device on airway secretions, bacterial samples were collected from the hands of the suction operators and the environment near the endotracheal tube orifice before and after the two suction processes. In addition, the satisfaction of the two suction methods was compared through the questionnaire of suction staff. Finally, with the assistance of this device, an attempt was made to complete the bronchoscopy without weaning of ventilator. Compared with open sputum suction, closed sputum suction has a smaller decrease in patients' blood oxygen saturation (P < 0.05), and no significant differences in other vital signs. Compared with open sputum suction, bacteria from the hands of suction staffs and the surrounding environment of the endotracheal tube were barely detected in closed suction. A questionnaire survey of sputum suction nurses suggested that the satisfaction with use and protective effect of the closed suction were better than open suction. In addition, bronchoscopy can be successfully completed with the assistance of this device, which is not possible for other breathing tubes. This closed sputum suction device has little effect on the oxygen saturation of patients but has excellent protective effects for medical staff against cross-infection. It has a unique advantage that can assist in completing the fiberoptic bronchoscopy with continuous ventilator-assisted breathing.

Using head-mounted eye trackers to explore children's color preferences and perceptions of toys with different color gradients.

This study investigated how color gradients affect the attraction and visual comfort of children aged 4 to 7 years. We analyzed 108 eye-tracking datasets, including the color attraction index (COI), visual comfort index (PUI), and saccade rate (SR). The findings revealed that children are more attracted to colors as saturation decreases and brightness increases within a specific range. Beyond this range, reduced saturation diminishes color appeal. Moderate brightness and contrast enhance visual comfort during play, while extremely low contrast hinders concentration. Warm colors (red, orange, and yellow) slightly dominate preferences; however, the roles of hue, saturation, and brightness in children's color preferences remain inconclusive. These insights have practical implications for age-appropriate toy design and marketing. Future research should explore age-specific color preferences for more targeted design strategies.

INVESTIGATION THE MAGNETIC PROPERTIES OF CsyCo1-0.5yFe2O4 NANOPARTICLES AT LOW MOLAR RATIO VARIATION

The effect of substitution ferrite by previously not used elements to control magnetic properties is of great interest to researchers. This study illustrates the effect of low substitution of Cs, with molar ratios of y of 0.0, 0.05, 0.15, and 0.25 on the structural and magnetic properties of CsyCo1-0.5yFe2O4nanoparticles. The synthesizing method was the co-precipitation method. The metal chlorides were used to perform the reaction in the distilled water using NaOH to reach a pH of 10. The X-ray diffraction, Field Emission Scanning Electron Microscopy, Electron Dispersive X-ray and Vibrating Sample Magnetometry analyses were conducted for all samples. All samples had the patternsof the spinel structure coincide to a high degree with the Co ferrite pattern. There was a general increase in the lattice constant with the increase in the Cs content, while the crystallite size decreased from about 18 to 12.2 nm as the molar ratio increased from 0 to 0.25. The Electron Microscopy investigation showed that all samples owing spherical nanoparticles with no other shapes. The average particle sizes were between 40 to 60nm, which increased Cs1+content. The magnetic parameters mainly showed a relatively high coercivity (wide loops) and a decrease in magnetization saturation (down to 50.43emu/g), crystalline anisotropic constant, and thesquareness ratio

Wicking-controlled interfacial water content for highly efficient solar desalination

Solar-driven interfacial evaporation offers a potential solution to address global freshwater scarcity. However, the water-thermal-vapor-salt imbalance issue severely affects the operating efficiency of the evaporator. This research examines the correlation among water supply height, spontaneous wicking rate, and interfacial water content. Subsequently, an engineering strategy is proposed to control the water concentration gradient within a two-dimensional solar absorber with vertical water supply channels. The results demonstrate that the hydrophilicity and internal structure of the material exert a crucial influence on the transport of bulk water. Specifically, longitudinal stripes within the water-conducting material promote a faster wicking rate and higher wicking height. This phenomenon occurs due to the combined effects of capillary forces and gravity, leading to a gradual decrease in liquid saturation along the capillary direction within the water-conducting material. By optimizing the water supply height and rate, the evaporation interface achieves a remarkable water evaporation rate of 1.50 kg m−2h−1. Building on this success, a novel configuration for a flow desalination evaporator is proposed, capable of sustaining the same evaporation rate even when operating continuously for 9 h in saltwater with a mass concentration of 20 %. Overall, this study emphasizes the importance of water and heat balance at the evaporative interface, reconciling conflicting requirements of interface flow and evaporation rate. These findings contribute to the development of highly efficient and reliable evaporators for sustainable freshwater generation.

Cushing syndrome in a 55-year-old case of small-cell lung cancer

Lung cancer is one of the most fatal types of cancer and paraneoplastic syndromes are commonly associated with lung cancer. Paraneoplastic Cushing can be associated with different types of tumors, especially small cell lung cancer (SCLC). The aim of this report was to describe the status of a patient presenting with progressive weakness, who did not have a previous medical history. Clinical examination revealed bilateral edema of the lower limbs. Lab results exhibited severe hypokalemia and metabolic alkalosis. physical examination showed elevated blood pressure. Imaging revealed a large mass with necrosis. Bronchoscopy was done and biopsy pathology showed SCLC. The patient underwent chemotherapy with cisplatin and etoposide. Following SCLC, the patient developed a type of paraneoplastic syndrome called Cushing syndrome. He experienced a severe decrease in saturation in the second session of chemotherapy and eventually died. With respect to the fact that most paraneoplastic syndromes are associated with poor response to treatment, high clinical suspicion is essential for the rapid diagnosis of these syndromes to improve outcomes.

Effect of Confining Pressure on CO2-Brine Relative Permeability Characteristics of Sandstone in Ordos Basin

CO2-brine relative permeability significantly impacts CO2 injection and is a key parameter for carbon dioxide storage simulation in saline aquifers. In the study of relative permeability, factors such as temperature, pressure, and reservoir rock physical properties play a crucial role. To better understand the impact of confining pressure on the CO2-brine relative permeability characteristics of sandstone in the Ordos Basin, five sets of CO2-brine relative permeability data were obtained through unsteady-state displacement tests conducted at various confining pressures ranging from 12 to 20 MPa. The research findings indicate that with an increase in confining pressure there is a slight decrease in irreducible brine saturation. Furthermore, the CO2 relative permeability in the irreducible brine state decreased by 57% as the pressure increased from 12 MPa to 20 MPa. The study demonstrates notable differences in the CO2-brine relative permeability curves under varying confining pressure conditions. As the confining pressure increases, the CO2 relative permeability curve decreases, while the brine relative permeability increases. The change in brine relative permeability is not as pronounced as that of CO2. These experimental results offer essential support for subsequent numerical calculations and practical applications in engineering. Experimental research holds significant importance in the assessment of storage potential and the prediction of the evolutionary patterns of CO2 migration.

Evaluating Airway Management in Patients With Trisomy 21 in the PICU and Cardiac ICU: A Retrospective Cohort Study.

Children with trisomy 21 often have anatomic and physiologic features that may complicate tracheal intubation (TI). TI in critically ill children with trisomy 21 is not well described. We hypothesize that in children with trisomy 21, TI is associated with greater odds of adverse airway outcomes (AAOs), including TI-associated events (TIAEs), and peri-intubation hypoxemia (defined as > 20% decrease in pulse oximetry saturation [Sp o2 ]). Retrospective database study using the National Emergency Airway Registry for Children (NEAR4KIDS). Registry data from 16 North American PICUs and cardiac ICUs (CICUs), from January 2014 to December 2020. A cohort of children under 18 years old who underwent TI in the PICU or CICU from in a NEAR4KIDS center. We identified patients with trisomy 21 and selected matched cohorts within the registry. None. We included 8401 TIs in the registry dataset. Children with trisomy 21 accounted for 274 (3.3%) TIs. Among those with trisomy 21, 84% had congenital heart disease and 4% had atlantoaxial instability. Cervical spine protection was used in 6%. The diagnosis of trisomy 21 (vs. without) was associated with lower median weight 7.8 (interquartile range [IQR] 4.5-14.7) kg versus 10.6 (IQR 5.2-25) kg ( p < 0.001), and more higher percentage undergoing TI for oxygenation (46% vs. 32%, p < 0.001) and ventilation failure (41% vs. 35%, p = 0.04). Trisomy 21 patients had more difficult airway features (35% vs. 25%, p = 0.001), including upper airway obstruction (14% vs. 8%, p = 0.001). In addition, a greater percentage of trisomy 21 patients received atropine (34% vs. 26%, p = 0.004); and, lower percentage were intubated with video laryngoscopy (30% vs. 37%, p = 0.023). After 1:10 (trisomy 21:controls) propensity-score matching, we failed to identify an association difference in AAO rates (absolute risk difference -0.6% [95% CI -6.1 to 4.9], p = 0.822). Despite differences in airway risks and TI approaches, we have not identified an association between the diagnosis of trisomy 21 and higher AAOs.

Tolerability of an Individualized Physical Rehabilitation Program in Patients Dependent on Inotropic Support With End-Stage Chronic Heart Failure

Aim To assess the tolerability of an individualized physical rehabilitation program (PRP) in inotrope-dependent patients with end-stage chronic heart failure (CHF).Material and methods This prospective randomized study included 120 men aged 18-65 years with left ventricular ejection fraction ≤30 % and blood pressure ≥90 / 60 mm Hg. Patients who have received dobutamine or dopamine for ≥2 weeks were randomized into two groups: group 1, 40 patients who participated in the PRP and group 2, 40 patients who did not participate in the PRP. Group 3 included 40 patients without inotropic support who participated in the PRP.Results Patients of groups 1 and 3 attended &gt;80 % of the scheduled classes without developing life-threatening adverse events (AEs) associated with exercise (E). After 6 months of the study, the exercising patients achieved a comparable (average) E intensity: 44 [35; 50]% and 45 [40;52]% of heart rate reserve and Borg scale scores 14 [12; 14] and 13 [11; 14] in groups 1 and 3, respectively (p&gt;0.05). Initially, after 3 and 6 months at the peak of physical activity in groups 1 and 3, there was no decrease in arterial blood oxygen saturation according to pulse oximetry (SpO2) &lt;93 %. At baseline, lactate levels in central venous blood at rest were normal in all groups. After 6 months, the lactate concentration was 1.1 mmol / l in group 1, 2.3 mmol / l in group 2, and 1.4 mmol / l in group 3 (р1-2=0.005; p2-3=0.008, respectively). At the E peak at baseline, after 3 and 6 months, comparable increases in lactate not exceeding 3 mmol / l were detected in groups 1 and 3.Conclusion The study allowed assessment of the tolerability of individualized PRP performed at the aerobic level of energy supply, in inotropic-dependent patients with CHF. Individualized 6-month PRP in inotropic-dependent patients with end-stage CHF, provided safety criteria are met, is well tolerated and does not increase the number of AEs associated with CHF and physical rehabilitation (PR). Continued inotropic support with dopamine or dobutamine should not be considered as a contraindication to PR in patients with CHF in the absence of E intolerance or life-threatening AEs.

Prospective clinical validation of the Empatica EmbracePlus wristband as a reflective pulse oximeter.

Respiratory diseases such as chronic obstructive pulmonary disease, obstructive sleep apnea syndrome, and COVID-19 may cause a decrease in arterial oxygen saturation (SaO2). The continuous monitoring of oxygen levels may be beneficial for the early detection of hypoxemia and timely intervention. Wearable non-invasive pulse oximetry devices measuring peripheral oxygen saturation (SpO2) have been garnering increasing popularity. However, there is still a strong need for extended and robust clinical validation of such devices, especially to address topical concerns about disparities in performances across racial groups. This prospective clinical validation aimed to assess the accuracy of the reflective pulse oximeter function of the EmbracePlus wristband during a controlled hypoxia study in accordance with the ISO 80601-2-61:2017 standard and the Food & Drug Administration (FDA) guidance. Healthy adult participants were recruited in a controlled desaturation protocol to reproduce mild, moderate, and severe hypoxic conditions with SaO2 ranging from 100% to 70% (ClinicalTrials.gov registration #NCT04964609). The SpO2 level was estimated with an EmbracePlus device placed on the participant's wrist and the reference SaO2 was obtained from blood samples analyzed with a multiwavelength co-oximeter. The controlled hypoxia study yielded 373 conclusive measurements on 15 subjects, including 30% of participants with dark skin pigmentation (V-VI on the Fitzpatrick scale). The accuracy root mean square (Arms) error was found to be 2.4%, within the 3.5% limit recommended by the FDA. A strong positive correlation between the wristband SpO2 and the reference SaO2 was observed (r = 0.96, P < 0.001), and a good concordance was found with Bland-Altman analysis (bias, 0.05%; standard deviation, 1.66; lower limit, -4.7%; and upper limit, 4.8%). Moreover, acceptable accuracy was observed when stratifying data points by skin pigmentation (Arms 2.2% in Fitzpatrick V-VI, 2.5% in Fitzpatrick I-IV), and sex (Arms 1.9% in females, and 2.9% in males). This study demonstrates that the EmbracePlus wristband could be used to assess SpO2 with clinically acceptable accuracy under no-motion and high perfusion conditions for individuals of different ethnicities across the claimed range. This study paves the way for further accuracy evaluations on unhealthy subjects and during prolonged use in ambulatory settings.

Understanding the role of the mitochondrial AD risk gene LACTB in myeloid cells.

AbstractBackgroundAlthough powerful evidence points out the importance of myeloid cells in Alzheimer’s Disease (AD), the relevance of immunometabolism requires further exploration. Our analysis integrating AD genetics and myeloid cell genomics reported that lower LACTB expression is protective for AD, and proteomics studies have confirmed it (Wingo et al., 2021). LACTB is a mitochondrial serin protein that may influence mitochondrial morphology and bioenergetics. LACTB levels are associated with succinyl‐carnitine levels (Ghazalpour et al., 2014, Suhre et al., 2011), a metabolite that has been linked to AD risk (unpublished). LACTB has also been nominated as a tumor‐related and an obesity gene, but its function is not well defined.MethodsTHP1 cells were treated for 6 days with small‐interfering RNA to reduce LACTB expression. iPS cells were CRISPR‐edited to obtain LACTB knock‐out (KO) lines and differentiated into microglial cells (iMGLs). Functional experiments were performed. Collected samples were outsourced for RNAseq, metabolomic and lipidomic analysis.Resultswe characterized, for the first time, the role of LACTB in myeloid cells. We observed that LACTB expression is increased upon differentiation (in iMGLs compared to iPSC, and in THP1 macrophages compared to monocytes) and LPS stimulation. The downregulation of LACTB in THP1 led to an increase in succinyl‐carnitine (predicted to be protective for AD), and in histone succinylation, which may modify the cell epigenetics. Transcriptomics revealed an increase in the oxidative phosphorylation, which was validated by Seahorse experiments, and in the immune response to interferon and virus. In addition, LACTB knock‐down polarized THP1 macrophages towards a DAM‐like state. Lipidomics reported significant changes in specific lipid classes and a decrease in chain saturation. These experiments will be repeated in iMGLs.ConclusionLACTB may play a role in cell differentiation and response to stimulus in myeloid cells by modifying mitochondrial respiration and lipid metabolism. As future directions, iMGLs will be xenotransplanted in WT and 5xFAD mice to study LACTB role in vivo. Unlike other AD risk genes, LACTB encodes an enzyme, reduced expression is protective, and succinyl‐carnitine can be used as a biomarker, which highlights it as a promising AD therapeutic target.

A Working Definition of Acute Chest Syndrome without the Requirement of Chest X-Rays

Introduction:Sickle Cell Disease (SCD) is a rare genetic disease in high-income countries where most of the cited literature used to guide clinical management emanate from. One of the most serious and potentially fatal complications of SCD is acute chest syndrome (ACS) which requires immediate medical attention. Approximately 50% of individuals with SCD will eventually develop ACS ( Blood 84, 643-649 (1994)). Despite the high frequency of ACS and its associated risk of death, no consensus diagnosis has been established that applies to children and adults living in low-middle income countries, where 95% of the children born with SCD are found. To create a uniform definition of ACS in both low, middle, and high-income countries, we propose using a new ACS definition that does not require a chest X-ray. Additionally, the new ACS definition should have a quantifiable and reproducible physical examination and clinical findings to allow for the reproducibility of the definition in all settings. This definition was developed over several years at Korle Bu Teaching Hospital, Accra Ghana, in pregnant women with SCD. Before we started the multidisciplinary team care in pregnant women with SCD, ACS was the most common cause of maternal death. Subsequently, based on the new ACS definition that did not require a chest X-ray, we developed strategies to prevent, aid early diagnosis, and treat ACS resulting in an 89% relative risk reduction of death. We refer to this new definition as the Korle Bu Teaching Hospital (KBTH)-ACS definition. In this study, we compare the ACS definition in the top 20 cited ACS articles as of July 2023 with our proposed KBTH-ACS definition. Methods:Using Google Scholar, we identified the top 20 cited articles with ACS in children or adults with SCD as primary or secondary outcomes. Each article was reviewed for the presence of the following criteria: chest x-ray, vitals, hemoglobin oxygen saturation, and lung physical exam findings. We compared the definition of ACS in the top 20 cited ACS articles to the KBTH-ACS definition that included the following features: “abnormal findings on lung auscultation and the presence of at least 2 of the following criteria: 1) temperature ≥ 38.0°C, 2) increased respiratory rate greater than the 90th percentile for age, positive chest pain or pulmonary auscultatory findings, 3) hemoglobin oxygen saturation decrease by ≥3% from a documented steady-state value on room air, and 4) a new radiodensity on chest roentgenogram. A diagnosis of pneumonia was considered an ACS episode.”. Results:The 20 most cited ACS articles required radiographical criteria to diagnose ACS. Fourteen of twenty articles included fever in their ACS definition. However, only 4 articles specified any temperature and all specified ≥ 38.5 ºC. A total of 17 articles mentioned the presence of lung or respiratory findings, but only 12 articles specifically identified the pulmonary findings. Among the 12 articles that specified lung findings, 5 included increased respiratory rate (tachypnea) without a specific definition, 2 included abnormal auscultatory findings, and 3 included hypoxemia/hypoxia in their definition. However. One study defined hypoxemia/hypoxia as “transcutaneous oxygen saturation &amp;lt;85% despite supplemental oxygen.”. Another article included “SpO2 of ≥ 3% compared to baseline steady-state values.”. In addition, among the twelve studies that specified respiratory findings, the following were present or absent features: chest pain (n=12), wheezing (n=3), coughing(n=3), and respiratory distress without a formal definition (n=3). No article included pneumonia in the ACS definition nor defined a threshold for tachypnea that was age-adjusted. None of the articles would allow for a direct comparison with the KBTH-ACS definition. Conclusion: All the 20 most cited ACS articles required a chest X-ray with various clinical and physical examination findings. Many of the ACS definitions in these studies were based on clinical impressions that were not quantifiable or reproducible. We propose using the KBTH-ACS definition in future ACS studies to improve generalizability, reproducibility, and genotype and phenotype studies designed to elucidate the genetic variation of lung disease in children and adults with SCD.

Evaluation of Leading Smartwatches for the Detection of Hypoxemia: Comparison to Reference Oximeter.

Although smartwatches are not considered medical devices, experimental validation of their accuracy in detecting hypoxemia is necessary due to their potential use in monitoring conditions manifested by a prolonged decrease in peripheral blood oxygen saturation (SpO2), such as chronic obstructive pulmonary disease, sleep apnea syndrome, and COVID-19, or at high altitudes, e.g., during sport climbing, where the use of finger-sensor-based pulse oximeters may be limited. The aim of this study was to experimentally compare the accuracy of SpO2 measurement of popular smartwatches with a clinically used pulse oximeter according to the requirements of ISO 80601-2-61. Each of the 18 young and healthy participants underwent the experimental assessment three times in randomized order-wearing Apple Watch 8, Samsung Galaxy Watch 5, or Withings ScanWatch-resulting in 54 individual experimental assessments and complete datasets. The accuracy of the SpO2 measurements was compared to that of the Radical-7 (Masimo Corporation, Irvine, CA, USA) during short-term hypoxemia induced by consecutive inhalation of three prepared gas mixtures with reduced oxygen concentrations (14%, 12%, and 10%). All three smartwatch models met the maximum acceptable root-mean-square deviation (≤4%) from the reference measurement at both normal oxygen levels and induced desaturation with SpO2 less than 90%. Apple Watch 8 reached the highest reliability due to its lowest mean bias and root-mean-square deviation, highest Pearson correlation coefficient, and accuracy in detecting hypoxemia. Our findings support the use of smartwatches to reliably detect hypoxemia in situations where the use of standard finger pulse oximeters may be limited.

Treatment of severe symptomatic aortic valve stenosis using non-invasive ultrasound therapy: a cohort study

Calcific aortic stenosis is commonly treated using surgical or transcatheter aortic valve replacement; however, many patients are not considered suitable candidates for these interventions due to severe comorbidities and limited life expectancy. As such, non-invasive therapies might offer alternative therapeutic possibilities in these patients. This study aimed to assess the safety of non-invasive ultrasound therapy and its ability to improve valvular function by softening calcified valve tissue. This prospective, multicentre, single-arm series enrolled 40 adult patients with severe symptomatic aortic valve stenosis at three hospitals in France, the Netherlands, and Serbia between March 13, 2019, and May 8, 2022. Patients were treated with transthoracically delivered non-invasive ultrasound therapy. Follow-ups were scheduled at 1, 3, 6, 12, and 24 months. The primary endpoints were procedure-related deaths within 30 days and improved valve function. We report the 6-month data. This study is registered at ClinicalTrials.gov, NCT03779620 and NCT04665596. 40 high-risk patients with a mean Society of Thoracic Surgeons score of 5·6% (SD 4·4) and multiple severe comorbidities were included. The primary endpoint, procedure-related mortality, did not occur; furthermore, no life-threatening or cerebrovascular events were reported. Improved valve function was confirmed up to 6 months, reflected by a 10% increase in mean aortic valve area from 0·58 cm2 (SD 0·19) at baseline to 0·64 cm2 (0·21) at follow-up (p=0·0088), and a 7% decrease in mean pressure gradient from 41·9 mm Hg (20·1) to 38·8 mm Hg (17·8; p=0·024). At 6 months, the New York Heart Association score had improved or stabilised in 24 (96%) of 25 patients, and the mean Kansas City Cardiomyopathy Questionnaire score had improved by 33%, from 48·5 (SD 22·6) to 64·5 (21·0). One serious procedure-related adverse event occurred in a patient who presented with a transient decrease in peripheral oxygen saturation. Non-serious adverse events included pain, discomfort during treatment, and transient arrhythmias. This novel, non-invasive ultrasound therapy for calcified aortic stenosis proved to be safe and feasible. Cardiawave.

Effects of COVID-19 infection in patients with autoimmune pulmonary alveolar proteinosis: a single-center study

BackgroundAutoimmune pulmonary alveolar proteinosis (aPAP) is a rare interstitial lung disease. COVID-19 is associated with worse prognosis in previous lung diseases patients. But the prognosis of aPAP patients after infection with COVID-19 is unclear. In December 2022, China experienced a large-scale outbreak of Omicron variant of the SARS-CoV-2. In this study, we aim to explore the clinical outcomes of aPAP patients infected with COVID-19.ResultsA total of 39 aPAP patients were included in this study. 30.77% patients had a decrease in oxygen saturation after COVID-19 infection. We compared the two groups of patients with or without decreased oxygen saturation after COVID-19 infection and found that patients who had previous oxygen therapy (decreased oxygen saturation vs. non decreased oxygen saturation: 6/12 vs. 4/27, P = 0.043), with lower baseline arterial oxygen partial pressure (74.50 ± 13.61 mmHg vs. 86.49 ± 11.92 mmHg, P = 0.009), lower baseline DLCO/VA% [77.0 (74.3, 93.6) % vs. 89.5 (78.2, 97.4) %, P = 0.036], shorter baseline 6MWD [464 (406, 538) m vs. 532 (470, 575) m, P = 0.028], higher disease severity score (P = 0.017), were more likely to have decreased oxygen saturation after COVID-19 infection.ConclusionaPAP patients with poor baseline respiration have a higher probability of hypoxia after COVID-19 infection, but fatal events were rare.

Sleep-Disordered Breathing, Hypoxia, and Pulmonary Physiologic Influences in Atrial Fibrillation.

Background We leverage a large clinical cohort to elucidate sleep-disordered breathing and sleep-related hypoxia in incident atrial fibrillation (AF) development given the yet unclear contributions of sleep-related hypoxia and pulmonary physiology in sleep-disordered breathing and AF. Methods and Results Patients who underwent sleep studies at Cleveland Clinic January 2, 2000, to December 30, 2015, comprised this retrospective cohort. Cox proportional hazards models were used to examine apnea hypopnea index, percentage time oxygen saturation <90%, minimum and mean oxygen saturation, and maximum end-tidal carbon dioxide on incident AF adjusted for age, sex, race, body mass index, cardiopulmonary disease and risk factors, antiarrhythmic medications, and positive airway pressure. Those with spirometry were additionally adjusted for forced expiratory volume in 1 second, forced vital capacity, and forced expiratory volume in 1 second/forced vital capacity. This cohort (n=42 057) was 50.7±14.1 years, 51.3% men, 74.1% White individuals, had median body mass index 33.2 kg/m2, and 1947 (4.6%) developed AF over 5 years. A 10-unit apnea hypopnea index increase was associated with 2% higher AF risk (hazard ratio [HR], 1.02 [95% CI, 1.00-1.03]). A 10-unit increase in percentage time oxygen saturation <90% and 10-unit decreases in mean and minimum oxygen saturation were associated with 6% (HR, 1.06 [95% CI, 1.04-1.08]), 30% (HR, 1.30 [95% CI, 1.18-1.42]), and 9% (HR, 1.09 [95% CI, 1.03-1.15]) higher AF risk, respectively. After adjustment for spirometry (n=9683 with available data), only hypoxia remained significantly associated with incident AF, although all coefficients were stable. Conclusions Sleep-related hypoxia was associated with incident AF in this clinical cohort, consistent across 3 measures of hypoxia, persistent after adjustment for pulmonary physiologic impairment. Findings identify a strong role for sleep-related hypoxia in AF development without pulmonary physiologic interdependence.

Реакція на дозовану гіпоксію у жінок, що перебували у стані хронічного стресу, зумовленого війною

Military stress has a traumatic effect on mental and physical health, and disrupts the adaptive capabilities of the body, in particular, its ability to adequately respond to hypoxia. However, the specifics of the reaction of the cardiorespiratory system to dosed hypoxia in individuals who experiencing warrelated chronic stress (WRCS) have not yet been elucidated. The peculiarities of the reaction of the cardiorespiratory system to dosed hypoxia in women experiencing WRCS were clarified. It was shown that during breathing of atmospheric air, the blood saturation level, lung ventilation indicators, and hemodynamics did not differ significantly between women exposed to WRCS and those not exposed to it. However, during a controlled hypoxic test (breathing a gas mixture with 12% oxygen for 20 min), women experiencing WRCS experienced a more significant decrease in blood saturation, indicating a lower tolerance to hypoxia. This is also evidenced by a reduced lung ventilation response to controlled hypoxia in the WRCS group, where the increase in ventilation primarily occurred due to an elevation in breathing rate rather than tidal volume. At the same time, the hemodynamic response to hypoxia in women with WRCS was characterized by a more substantial increase in heart rate and systolic arterial pressure. Thus, it was established that in women who were in the state of HCV, the body’s resistance to the effects of hypoxia decreases. At the same time, in conditions of hypoxia, the nature of their breathing changes, and the compensatory growth of pulmonary ventilation decreases, but the growth of hemodynamic indicators increases.

Effects of phenylephrine on systemic and cerebral circulations in humans: a systematic review with mechanistic explanations.

We conducted a systematic review of the literature reporting phenylephrine-induced changes in blood pressure, cardiac output, cerebral blood flow and cerebral tissue oxygen saturation as measured by near-infrared spectroscopy in humans. We used the proportion change of the group mean values reported by the original studies in our analysis. Phenylephrine elevates blood pressure whilst concurrently inducing a reduction in cardiac output. Furthermore, despite increasing cerebral blood flow, it decreases cerebral tissue oxygen saturation. The extent of phenylephrine's influence on cardiac output (r = -0.54 and p = 0.09 in awake humans; r = -0.55 and p = 0.007 in anaesthetised humans), cerebral blood flow (r = 0.65 and p = 0.002 in awake humans; r = 0.80 and p = 0.003 in anaesthetised humans) and cerebral tissue oxygen saturation (r = -0.72 and p = 0.03 in awake humans; r = -0.24 and p = 0.48 in anaesthetised humans) appears closely linked to the magnitude of phenylephrine-induced blood pressure changes. When comparing the effects of phenylephrine in awake and anaesthetised humans, we found no evidence of a significant difference in cardiac output, cerebral blood flow or cerebral tissue oxygen saturation. There was also no evidence of a significant difference in effect on systemic and cerebral circulations whether phenylephrine was given by bolus or infusion. We explore the underlying mechanisms driving the phenylephrine-induced cardiac output reduction, cerebral blood flow increase and cerebral tissue oxygen saturation decrease. Individualised treatment approaches, close monitoring and consideration of potential risks and benefits remain vital to the safe and effective use of phenylephrine in acute care.