Percentage Of Oxygen Saturation Research Articles

Theoretical Evaluation of Simultaneous Optical Measurement Method for Hemoglobin Concentration, Oxygen Saturation, and Water Percentage in Blood Based on Multi-parameter Optimization

Theoretical Evaluation of Simultaneous Optical Measurement Method for Hemoglobin Concentration, Oxygen Saturation, and Water Percentage in Blood Based on Multi-parameter Optimization

A Study of how the Serum Levels of Inflammatory Markers Correlate with Hemoglobin Oxygen Saturation Percentage and the Type of Respiratory Support Received by Covid-19 Patients Hospitalized in Intensive Care Units

Aim This study aimed to shed light on how serum levels of interleukin-6 (IL-6), lactate dehydrogenase (LDH), and C-reactive protein (CRP) correlate with hemoglobin oxygen saturation percentage (SpO2) and the type of respiratory support received among COVID-19 patients hospitalized in COVID-19 intensive care units. Background The clinical care of patients who suffer from COVID-19 requires knowledge of laboratory findings and the way these findings are linked with the type of respiratory support. Methods This descriptive-analytical study was conducted using data from the clinical records of 31 patients hospitalized in the intensive care unit at 22nd-Bahman Hospital in Khaf, Eastern Iran, during the first half of 2021. The study utilized a checklist developed by the researcher for data collection. The data were analyzed with Kolmogorov-Smirnov, independent t, one-way analysis of variance, and Tukey's post hoc statistical tests in the SPSS-22 statistical package. The significance level was established at p <0.05. Results The mean CRP, LDH, and serum levels of IL-6 were significantly higher in COVID-19 patients with SpO2 <93 than in patients with SpO2 ≥93 (p <0.05). Patients receiving intubation and non-invasive respiratory support exhibited significantly greater serum levels of IL-6, CRP, and LDH than patients receiving other respiratory support (p <0.05). The mean CRP, serum levels of IL-6, and LDH were significantly lower among survivors than those who died (p <0.01). Conclusion Understanding the relationship between the serum levels of IL-6, CRP, LDH, and SPO2 and the type of respiratory support can help predict the management of acute respiratory patients, but this decision-making method based on serum levels should be further investigated. and to be compared with the current methods of management of treatment of acute respiratory patients.

Effect of Thiamethoxam Insecticide on Productive Performance of Nile tilapia as well as Water Quality of Fish Tanks

Thiamethoxam (TMX) is a highly toxic systemic neonicotinoid pesticide and its entry into water bodies can greatly endanger human health and aquatic ecosystems. Little is known about the effect of thiamethoxam on Nile Tilapia. Particularly so this experiment was scheduled for three weeks to evaluate the toxic effects of thiamethoxam on productive performance of fish as well as water quality. The used insecticide was Actara 25 WG manufactured by Sygenta, Egypt and it was purchased from Egyptian Company for Seeds and Agricultural Chemicals. It composed of 250 g/kg Thiamethoxam. A total of 200 Oreochromis niloticus with an average initial weight of 15 ± 5 g have been obtained from a commercial fish farm in Kafr Elsheikh province, Egypt. Fish were randomly allotted to five replicated treatments and they were kept at a density of 10 fish / aquaria. Four different concentrations of the insecticide were tested with three replicates of fish for each treatment beside a control group where with no insecticide were used. Tested concentrations of studied insecticide was selected according to lethal concentration 50 (LC50) for Thiamethoxam was 500 mg/l. Statistical analysis of the recorded data clarified that the levels of pH, dissolved oxygen levels (DO), oxygen saturation percentage (DO%) and salinity were significantly different between thiamethoxam treated groups and the control group. In addition, there was a significant difference in final weight and weight gain of fish under experiment in all treatments when compared with the control group. In addition, the lowest significance in the final weight and weight gain was observed at the high chronic dose. Finally, there were no significant differences in mortalities between various treatment groups and the control group with exception to high subacute dose that showed the highest significance of all groups and it was clear that mortalities were increased with increasing thiamethoxam dose as no mortalities were observed in the control group. The present trial clearly showed the toxic effects of thiamethoxam on water quality of fish tank as well as performance and mortality rate in Nile tilapia fish that were live for three weeks in polluted water. Moreover, the result of the present study is of great public health importance because of thiamethoxam residue effects on human health.

The Effect of Oral Montelukast in Controlling Asthma Attacks in Children; A Randomized Double-blind Placebo Control Study

Oral Montelukast is recommended as maintenance therapy for persistent asthma, but there is controversy regarding its effectiveness in controlling asthma attacks. The present study was conducted to investigate the clinical efficacy of oral Montelukast for asthma attacks in children.
 This study was conducted as a double-blind placebo-controlled clinical trial on 80 children aged 1-14 years with asthma who were admitted to the emergency department of Bahrami Children's Hospital (Tehran, Iran) during one year. Patients were randomly divided into case and control groups. In addition to the standard asthma attack treatment, Montelukast was prescribed in the case group and placebo in the control group for one week. Patients were evaluated in terms of asthma attack severity score and oxygen saturation percentage (SpO2) in room air as primary outcomes 1, 4, 8, 24 and 48 hours after admission.
 In the first 48 hours, there was no significant difference in the score of asthma attack severity and SpO2 between the case and control groups. There was no significant difference between the groups in terms of length of hospitalization or number of admissions to the intensive care unit. None of the patients were re-hospitalized after discharge.
 The results of this study showed that the use of Montelukast along with the standard treatment of asthma attacks in children has no added benefit.

Vaccine effectiveness against the B.1.617.2 in the intensive care unit.

Severe acute respiratory syndrome-coronavirus 2 and its variants are still a concern for the World. The effectiveness of the BioNTech and Sinovac vaccines against the B.1.617.2 variant, particularly in the intensive care unit, has been unclear. This study aimed to investigate the vaccine effectiveness of BioNTech and Sinovac vaccines in reducing severe disease, intubation, and mortality rates in B.1.617.2 infected patients followed in the intensive care unit. The data of 208 unvaccinated and 234 vaccinated B.1.617.2 variants were retrospectively reviewed. Severe disease status, complaints, the percent oxygen saturation in the blood at the first admission, and other clinical information during follow-up were recorded. With the BioNTech and Sinovac vaccines being the most common in the region, mortality rate, severe disease, and intubation were more frequent in the unvaccinated group. As for survival rates, 58.5 (137) of the vaccinated and 35.1 % (73) of the unvaccinated survived. In the vaccinated group, 64.3 % (27) of vaccinated with 3 Sinovac, 80 % (16) of 2 Sinovac and 1 BioNTech, and 71.7 % of 2 BioNTech survived. Vaccination with 2 doses of BioNTech and 3 doses of Sinovac reduces mortality. Furthermore, 2 doses of Sinovac and 1 dose of BioNTech are more protective.

Evaluation of functional aerobic exercise capacity among chronic e-cigarette users compared to combustible cigarette smokers and non-smokers: a comparative study

BackgroundElectronic cigarettes or e-cigarettes have gained significant popularity as an alternative to traditional combustible tobacco smoking particularly among the youth. Although there is a growing prevalence of e-cigarette usage, the effects on cardiovascular function and physical capacity have not been adequately studied. The toxic products in combustible tobacco cigarettes negatively impact functional exercise capacity. However, the available data regarding the effect of e-cigarette use on functional exercise capacity are scarce. Thus, in the current study, we aimed to evaluate the functional aerobic exercise capacity among chronic e-cigarette users compared to combustible cigarette smokers and non-smokers.ResultsThis comparative, cross-sectional study was conducted on 105 healthy volunteers. Participants were assigned into three study groups each consisting of 35 participants: chronic e-cigarette users, combustible cigarette smokers, and a non-smoker control group. Basal demographic and clinical data were similar in all groups. Mean heart rates and respiratory rates were significantly higher among e-cigarette smokers and combustible cigarette smokers compared to non-smoker controls (p < 0.001). Chronic e-cigarette users and combustible cigarette smokers had shorter 6-MWT distances compared to non-smokers (508.3, 488, and 616.6 m, respectively, p < 0.001). Borg scale scores after performing the six-minute walking test were significantly higher in chronic e-cigarette users and combustible cigarette smokers groups compared to non-smokers, where perceived exertion (4.9, 5.5, 2.1, respectively, p < 0.001), dyspnea (5.7, 6.5, 0.1, respectively, p < 0.001) and leg fatigue (4.2, 5.4, 1.4, respectively, p < 0.001).ConclusionIn this cross-sectional study, significant evidence demonstrates that e-cigarette use is not harmless. This was particularly presented in apparently healthy e-cigarette users in comparison to the healthy non-smoker control group. Chronic e-cigarette use is associated with reduced functional capacity compared to non-smoker controls. This was signified by decreased 6MWT walking distances, higher Borg scale scores, and lower oxygen saturation percentages among the chronic electronic cigarette users as compared to non-smoker controls after performing the six-minute walking test. All the evaluated parameters in the current study were similarly reduced among both the e-cigarette users group and the combustible cigarette smokers group compared to non-smokers with no statistically significant differences between both smoker groups.

Six-minute walk test and factors affecting exercise capacity in children with cystic fibrosis.

This study aimed to compare the result of the six-minute walk test (6MWT) in patients with cystic fibrosis (CF) aged < 20 years old and individuals without CF. In this cross-sectional study, 50 children and adolescents with CF and 20 children and adolescents without CF underwent the 6MWT. Vital signs before and immediately after the 6MWT and six-minute walk distance (6MWD) were evaluated. The mean change in heart rate, percentage of peripheral oxygen saturation (SpO2%), systolic blood pressure, respiratory rate, and dyspnea severity during the 6MWT was significantly higher in patients with CF. In the case group, 6MWD was associated with regular chest physical therapy (CPT) and forced expiratory volume (FEV)> 80%. Patients with CF receiving regular CPT or mechanical vibration and with FEV in the first second > 80% showed better physical capacity during the 6MWT (smaller Sp02% decline and lower dyspnea perception). Children and adolescents with CF have lower physical capacity compared to individuals without CF. CPT and mechanical vibration could be used to increase physical capacity in this population.

The Effect of Breathing Exercises on Respiratory Condition After Coronary Artery Bypass Surgery

Background: Respiratory complications are prevalent in coronary artery bypass graft (CABG) surgery. Breathing exercises are efficient and cost-effective techniques to eliminate this problem. Objectives: This study investigated the effect of simultaneous breathing exercises on patients' respiratory condition after CABG surgery. Methods: In a randomized controlled clinical trial, 52 CABG candidates were allocated to two intervention and control groups. The control group received routine breathing exercises (incentive spirometry and vibration). Besides routine exercises, the intervention group performed exercises such as pursed-lip breathing, diaphragmatic breathing, incentive spirometry, and effective coughing for three days after the surgery. The incidence of atelectasis, oxygen saturation, lung auscultation, and the patients' satisfaction with the respiratory function was measured and recorded before and after the surgery in both groups. The collected data were analyzed in SPSS v. 22 at a significance level of &lt; 0.05. Results: The patients' mean age was 60.9 ± 9.5 years, and 26 (51%) were male. There was no significant difference between the patients in underlying parameters. None of the patients in the two groups had atelectasis before the surgery. However, four days after the surgery, 40% of the patients in the control group and 23% of those in the intervention group suffered from atelectasis complications. The visual analog scale (VAS) score increased after surgery in the intervention group, although the difference was insignificant. Moreover, the arterial oxygen saturation percentage and breathing rate increased in the intervention group. No significant difference was observed between the two groups regarding crackles at different hours after surgery, although they were relatively less in the intervention group. Conclusions: Breathing exercises, especially combined breathing exercises, improve respiratory function after open heart surgery.

Predicting acute pulmonary embolism in COVID-19.

Acute pulmonary embolism (PE) is a life-threatening condition in patients with Coronavirus disease-2019 (COVID-19). Computed tomography pulmonary angiography is the preferred test to confirm the diagnosis. However, computed tomography pulmonary angiography is expensive and is not available in every clinic. This study aimed to determine whether clinical findings, symptoms, and parameters that are cost-effective and available in many clinics such as C-reactive protein (CRP) lymphocyte ratio (CLR), and ferritin CRP ratio (FCR) can be used in the diagnosis of PE in patients with COVID-19. Out of the reviewed files, 127 patients were diagnosed with PE, whereas 105 patients had no PE. At the first admission, laboratory parameters, complaints, respiratory rate, and percent oxygen saturation in the blood (SpO2) with a pulse oximeter were recorded for each patient. Eosinophil levels remained lower, whereas ferritin lymphocyte ratio and CLR were higher in the PE group. Patients with more elevated ferritin, CRP, and CLR had an increased mortality risk. Shortness of breath and tiredness was more common in the PE group. A decrease in eosinophil levels, whereas an increase in CLR, D-dimer, and CRP may predict PE. Elevated CLR is highly predictive of PE and is associated with increased mortality risk. COVID-19 patients with a CLR level above 81 should be investigated for PE.

Oxygen saturation profile in traumatic brain injury animal model after propofol administration.

Traumatic brain injury (TBI) is a traumatic that often leads to death due to untreatable cerebral hypoxia, indicated by oxygen saturation of <90%. Cerebral hypoxia is rarely monitored and thereby often overlooked as a cause of mortality and monitoring oxygen saturation is an accurate method to detect the condition. Propofol, an anesthetic agent, is commonly used in the management of TBI; however, its effect on brain tissue and cerebral hypoxia in TBI cases is not well understood. The aim of this study was to evaluate the profile of oxygen saturation in TBI animal model after propofol administration. A laboratory experimental study was conducted, involving 18 male Rattus novergicus rats (aged 4-8 weeks with weight between 150-200 grams) divided into three different treatment groups (non-TBI, TBI without propofol, and TBI with propofol). Oxygen saturation was measured regularly from day 1 to day 8 using pulse oximetry. The oxygen saturation percentages were compared between the TBI rats with and without propofol administration using independent Student t-rest. The results revealed significant reductions of oxygen saturation levels of animals within propofol-treated TBI group compared to that of the untreated-TBI group (p<0.05), with the average oxygen saturation ranging from 80.8%±6.96% vs 86.8%±5.48%. This finding suggests a reducing effect of propofol administration on oxygen saturation levels in rats with TBI and this potentially causes cerebral hypoxia.

Regular practice of Kung Fu and Taekwondo improve Chilean adults’ health and quality of life during the COVID-19

PurposeThis study aims to investigate the impact of regular Kung Fu and Taekwondo practice on the health and quality of life among elderly individuals in the Maule region, Chile.Design/methodology/approachThe authors designed a 12-week Kung Fu and Taekwondo workshop with activities suitable for their age. Through semistructured interviews (at the beginning and the end of the workshop), along with periodic monitoring of vital signs and cardiovascular components, the authors observed an improvement in participants’ physical (strength, speed of reaction and flexibility) and psychological conditions (self-esteem and resilience), quality of life (relationships with family and friends and ability to deal with stressful events in working life) and health (waist circumference, percentage of oxygen saturation in blood, blood pressure, among other values).FindingsFrom these results, the authors affirm that this workshop improves health and physical condition and helps the participants develop the coping capacity to deal with stressful situations and complicated interpersonal relationships. In this sense, the authors conclude that Kung Fu and Taekwondo as regular sports activities can benefit senior citizens’ aging process.Originality/valueThis research is based on an original study project.

Using the 6-min walk test to assess the clinical response to mepolizumab and conventional therapy in severe eosinophilic asthma.

Severe asthma limits exercise to avoid respiratory symptoms. The objective of the present study was to investigate the role of the 6-min walk test (6MWT) in severe asthma. Consecutive patients with severe eosinophilic asthma were enrolled. A 6MWT was performed before and after 12 months. Inhaled therapy dose, oral corticosteroids dose, pulmonary function tests, eosinophil blood count, fractional exhaled nitric oxide (FeNO), Asthma Control Test (ACT) score and responses to the Asthma Quality of Life Questionnaire (AQLQ) were also recorded. Of the 22 patients enrolled, 13 were treated with mepolizumab 100 mg every 4 weeks in addition to conventional therapy and nine with conventional therapy only. The majority of the patients were treated with high-dose inhaled corticosteroids/long-acting β-agonists/long-acting muscarinic receptor antagonists, while approximately half were on continuous oral corticosteroids. After 12 months, the mepolizumab group only showed a significant improvement in pulmonary function tests (percentage forced expiratory volume in 1 s and percentage forced expiratory flow at 25-75% forced vital capacity (FEF25-75%), both p<0.001; percentage forced vital capacity, p<0.01) and clinical laboratory parameters (eosinophil count, FeNO measured at a flow rate of 50 mL·s-1, ACT and AQLQ, p<0.001). No significant changes in the proportion of patients using continuous oral corticosteroids and high-dose inhaled corticosteroids/long-acting β-agonists/long-acting muscarinic receptor antagonists were observed in either group (p>0.05). By paired comparisons, statistically significant improvements of the mean 6-min walk distance (6MWD) were observed in the mepolizumab (p<0.001) and conventional therapy (p<0.01) groups, while no improvement was seen in dyspnoea Borg scale, heart rate, percentage oxygen saturation or systolic and diastolic blood pressure. 6MWD showed significant direct correlations with ACT (r=0.5998, p<0.001), AQLQ (r=0.3978, p=0.009) and FEF25-75% (r=0.3589, p=0.017). The 6MWT could complement severe asthma assessment and be relevant in evaluating the objective response to treatment, including biological therapies like mepolizumab.

Evaluation of the Role of Hemoperfusion on Mortality and Morbidity in Patients with Severe Coronavirus Disease 2019 (COVID- 19)

Background: Cytokine storm in severe Covid-19 disease is one of the leading causes of death in these patients. Hemoperfusion is a method used to purify the blood from toxins and inflammatory factors. The aim of this study was to evaluate the effect of hemoperfusion on mortality and morbidity in patients with severe Covid - 19 disease.&#x0D; Methods: This was a retrospective study which performed by reviewing the files of 30 patients with severe Covid-19 disease referred to Sina Hospital affiliated to Tehran University of Medical Sciences in 2020. Thirty patients with severe covid-19 disease and positive PCR participated in the study. All patients received routine treatment protocol for covid-19. Hemoperfusion was used for 15 patients in addition to receiving routine care. The remaining 15 patients were included in the control group. Patients in the hemoperfusion group underwent four sessions of hemoperfusion using continuous renal replacement therapy with continuous venovenous hemofiltration.&#x0D; Results: the ICU length of stay in the control and hemoperfusion groups was 3.40 ± 11.40 and 9.65 ± 16.33 days, respectively (P= 0.075). 8 patients died and 7 patients were discharged in the control group, but 11 patients died and 4 patients were discharged in the hemoperfusion group (P= 0.256). The respiratory rate of patients in the control and hemoperfusion groups decreased from 7.43 ± 29.40 to 4.03 ± 24.60 and from 6.11 ± 31.60 to 5.04 ± 24.46, respectively (P &lt; 0.001). The percentage of arterial blood oxygen saturation in the control and hemoperfusion groups increased from 90.86 ± 5.61 to 93.06 30 4.30 and from 92.33 26 3.26 to 92.06 31 5.31, respectively (P= 0.456).&#x0D; Conclusion: Hemoperfusion could not prevent the mortality of patients and finally out of 15 patients, 11 patients died and 4 patients were discharged. Also, no significant difference was observed between the two groups in terms of arterial blood oxygen saturation.

BLOCK OF THE ANGIOTENSIN PATHWAYS EFFECTS FLOW-VOLUME SPIROMETRY IN PATIENTS WITH SARS-COV-2 INFECTION

Objective: Angiotensin Converting Enzyme 2 (ACE2) pathways inhibitors have been first evaluated in COVID-19 patients for the risk of poor prognosis. Pulmonary function tests (PFTs) are the main diagnostic tools for most respiratory diseases. Few data are present in follow-up PFTs according to hypertension or treatment. We evaluated patients that are hypertensives and not and the role of ACE2i/ARB through flow-volume spirometry in follow-up after infection recovery. Design and method: We evaluated 112 Caucasian patients 3-6 months after Covid-19 disease, i.e. after the date of negative molecular/antigenic nasopharyngeal swab. The series of patients showed a great variability due to a wide spectrum of age, the severity of disease manifestations, hospitalization, invasive/non-invasive ventilation, comorbidities, the presence/absence of a previous pneumological diagnosis, and the variants of the virus. Patients were divided into those who were hypertensives (Group1, 18 females and 30 males, aged 63.47±14.24), and who were not (Group2, 32 females and 32 males, aged 53.03±16.66). Group1 was further analysed according to treatment: patients in ACEi/ARB treatment (Group1A, 23 females and 12 males, aged 63.63±10.40) and those who not (Group1B, 6 females and 7 males, aged 53.03±16.66). Distal airflow obstruction (DAO) was evaluate as forced expiratory flow (FEF) at 25%, 50% and 75% of total flow. PFTs values were related to age, sex and BMI before comparison. Results: Group1 presented lower peripheral oxygen saturation percentage (SpO2) vs Group2 (p&lt;0.05). Spirometry data were worst in Group1: Forced expiratory volume at first minute (FEV1) (p&lt;0.05), Forced vital capacity (FVC) (p&lt;0.05), and Tiffenau Index (p&lt;0.05). There was a DAO in Group1. In Group 1, we found also a reduction in FEF 25 (p&lt;0.05), FEF 50 (p&lt;0.05), and FEF 25-75 (p&lt;0.05), and in FEF 75 (p&lt;0.05). There was no difference in those parameters comparing Group1A vs Group1B. Conclusions: In hypertensives the indexes of respiratory function were shifted towards the lower limits (albeit within normal limits). These parameters were significantly reduced compared to controls. Treatment with ACEi/ARB didn’t affect PFTs at follow-up evaluation after recovery. Thus, COVID-19 is not only a pulmonary, but also a vascular disease worsening when a previous CV comorbidity.

COVID-19: Maternal deaths in the tertiary health care center

The maternal mortality rate is increasing due to associated complications of labor, the severity of infection, and co-morbidities. The impact of COVID-19 infection on pregnant women data is insufficient in the literature, so in the present study, we are evaluating the rate of maternal mortality due to COVID-19 infection in McGANN Teaching District Hospital a tertiary health care center.The objective: to evaluate the rate of maternal mortality due to COVID-19 infection.Materials and methods. This is a single-center retro-prospective study, which included all maternal mortalities with COVID-19 infection admitted to the department of obstetrics and gynecology, McGANN teaching district hospital a tertiary health care center from June 2020 to October 2021. COVID-19 infected 15 pregnant women who died during hospitalization, treatment, labor, and after labor due to various complications. Data were collected from the medical record section and presented in an excel sheet and analyzed using SPSS software.Results. In the study period, maternal mortality due to COVID-19 infection was found to be more in the less than 30 years age group (73.3 %). Nearly all cases were admitted with complaints of fever (40 %), cough (53.3 %), abdominal pain (13.3 %), and breathlessness (80 %). Out of 15 maternal deaths, most of the cases are found to be primiparous (46.7 %), and the time from delivery to a death varies from 1-14 days. Nearly 66.7 % of cases had a gestational period of fewer than 36 weeks. Pulse rate, respiration rate, inflammatory markers, prothrombin time, liver enzymes, and blood glucose levels were elevated. The total protein hemoglobin and oxygen saturation percentage declined in the cases. The known co-morbidity present in the cases associated with maternal mortality was hypertension (20 %), diabetic mellitus (13.3 %), valvular heart disease (6.7 %), and pre-eclampsia (6.7 %). The most cause of death was acute respiratory distress syndrome (80 %).Conclusions. In this study the severe infection with co-morbidities showed an increased risk of severe morbidity and mortality.

Future climate-induced changes in mixing and deep oxygen content of a caldera lake with hydrothermal heat and salt inputs

Vertical profiles of temperature, salinity and dissolved oxygen in Crater Lake, a caldera lake in the Oregon Cascade Range that receives hydrothermal inputs of heat and salt, were simulated with a 1-dimensional model. Twelve Global Circulation Models and two Representative Concentration Pathways (RCPs) were used to develop boundary conditions from 1950 to 2099. The model simulated the ventilation of deep water initiated by reverse stratification and subsequent thermobaric instability. All models predicted a reduction in the frequency of deep ventilation events, from an ensemble median frequency of 5.4 winters decade−1 during 1950–2005 to 4.3 (RCP4.5) or 2.5 (RCP8.5) winters decade−1 during 2045–2099. Favorable conditions for thermobaric instability-induced mixing currently occur infrequently and will become rare in the future. The salinity gradient resulting from hydrothermal inputs presents an additional barrier to thermobaric instability that will continue through 2099. A redistribution of salt to the deep lake may prevent ventilation all the way to the bottom in the future. Hypolimnetic dissolved oxygen percent saturation remained above 75% within the 21st century, consistent with oligotrophy and very small oxygen demands. The rate of change in all variables accelerated approaching 2099, coincident with elimination of winter reverse stratification. Historically, about half of the hydrothermal heat added to Crater Lake has been vented to the atmosphere. In the RCP8.5 scenario, the hydrothermal heat will cease to be vented to the atmosphere by the end of the 21st century, and then the temperature of the deep waters will increase rapidly.

T cell receptor repertoire as a novel indicator for identification and immune surveillance of patients with severe obstructive sleep apnea.

Obstructive sleep apnea (OSA) is the most prevalent sleep disturbance that affects approximately 936 million people worldwide and leads to extensively increased incidence of cardiovascular disease, metabolic syndrome, neurological disorders, and traffic accidents. Severe OSA patients suffer a significantly higher risk of complications and worse comorbidity outcomes. Notwithstanding, with inadequate access to contact diagnosis based on polysomnography (PSG), numerous patients with severe sleep apnea have not been diagnosed, especially during the pandemic. Moreover, how the T cell immunity is impaired in OSA remains largely unknown. We primarily investigated the T cell receptor (TCR) repertoires of 50 patients with severe OSA, 23 patients with mild-to-moderate OSA, 23 patients without OSA, and 157 healthy individuals, from their peripheral blood. Firstly, we compared the clinical characteristics, blood cell counts, the ratio of neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR), and CD4+/CD8+T cell count between groups. Then, we compared the diversity, clonotypes, unique VJ alleles in patients with different disease severity. Furthermore, by identifying a series of disease-associated amino acid sequences, we employed a repeated hold-out machine learning strategy to explore the optimal algorithm for calculating the TCR repertoire characteristic Index (OSA-TCI). We further confirmed its relation with clinical features by linear regression analysis. Moreover, in followup of severe OSA patients who accepted adherent non-invasive ventilation, we assessed the changes of TCR repertoires, OSA-TCI, ESS, NLR, PLR, and CD4+/CD8+T after therapy. We found an unexpected increase in diversity and clonotypes in the TCR repertoire of OSA patients. Furthermore, we successfully developed a novel indicator termed OSA-TCI to summarize the unique repertoire alteration, which provided 90% of sensitivity and 87% of specificity in distinguishing severe OSA. In rationalization, OSA-TCI was found correlated to AHI, BMI, hemoglobin, N1, N2 percentage of sleep, snoring, smoking and lowest oxygen saturation, but only independently related to AHI (R=0.603) and smoking (R=0.22). Finally, we observed OSA-TCI in the eight severe patients decreased significantly after home noninvasive ventilation for three months during follow-up, consistently in line with the TCR repertoire improvement. In contrast, NLR, PLR, and the ratio of CD4+/CD8+T cell count were found useless to diagnose and therapeutic surveillance of severe OSA. Our study is the first to unveil the TCR repertoire alteration in OSA, indicates possible insidious autoimmune mechanisms underlying OSA, and suggests that TCR repertoires serve as a convenient peripheral blood biomarker for OSA assessment without long-time contact and facility/instrument occupation. It may shed light on future diagnostic, immunological, pathophysiological, and prognostic research on OSA.

320 Oxygenated Peritoneal Perfluorodecalin Improves Response to Normobaric Hypoxic Exposure in Swine

OBJECTIVES/GOALS: Patients suffering from respiratory failure have few options to support oxygenation and carbon dioxide removal aside from mechanical ventilation. Our objective was to test a novel extrapulmonary mechanism of gas exchange via peritoneal oxygenated perfluorocarbon (PFC) in a large animal model. METHODS/STUDY POPULATION: Using two 50 kg swine, hypoxia was modeled with subatmospheric oxygen and hypercarbia induced with acute hypoventilation. Through a midline laparotomy, cannulas were placed into the peritoneal space to allow for PFC infusion and circulation. After abdominal closure, these cannulas were connected to a device capable of draining, oxygenating, and infusing PFC. One animal was subjected to acute hypoxia (12% FiO2) and another animal to acute hypoventilation (4 breaths per minute). Primary outcomes were times for SpO2 to reach 75 mmHg, respectively. Trials were performed without PFC and with PFC dwelling or circulating through the peritoneal space, during which abdominal and bladder pressures were monitored and maintained under 20 mmHg by regulation of the PFC volume contained in the animal. RESULTS/ANTICIPATED RESULTS: In the animal subjected to acute hypoxia (12% FiO2), survival time improved from 5:55 to 20:00 (min:sec) after 2.5 liters of oxygenated PFC was instilled in the peritoneal space. Oxygen percent saturation of PFC before and after dwelling in the peritoneal space was measured at 100% before and 70% after dwelling in the animal during this hypoxic period corresponding with a gas transfer of 300 mL of oxygen over the 20-minute trial (i.e., 15 mL/min). Continual PFC circulation did not further extend the survival time during hypoxic conditions over PFC dwelling in the abdomen. In the animal that was acutely hypoventilated, there were no detectable differences in the rate of CO2 accumulation as measured by EtCO2 or direct blood pCO2 measurements with PFC dwelling or circulating through the peritoneal space. DISCUSSION/SIGNIFICANCE: Oxygenated PFC dwelling in the peritoneal space increased the duration of systemic arterial blood saturation remaining greater than 50% during normobaric hypoxic (12% FiO2) conditions but did not appreciably clear blood carbon dioxide during hypoventilation. Future experiments will focus on maximizing the rate of systemic oxygen uptake.

Interventional Effect of Quiet Time Protocol on the Physiological Parameters of Premature Neonates Admitted to the Neonatal Intensive Care Unit

Background: Premature neonates are a group of high-risk patients who need intensive medical care and hospitalization in the neonatal intensive care unit (NICU) for their survival. In the NICU environment, there are highly stressful stimuli that have a negative effect on the physiological parameters of premature neonates. One of the interventions that improve the physiological parameters of neonates is the implementation of the quiet time protocol. Objectives: The present study aimed to investigate the effect of the quiet time protocol intervention on the physiological parameters of premature neonates admitted to the NICU. Methods: This quasi-experimental study was performed on 62 premature neonates selected through a convenient sampling method out of the neonates admitted to the NICU. First, the samples of the control group were collected. A demographic data questionnaire was employed. Neonates in the two groups were examined for 60 min during three phases before, during, and after the intervention in the evening shift of 15 - 17 o’clock. Data were analyzed using the SPSS software version 22 by the chi-squared test, repeated measures analysis of variance (ANOVA), and t-test. P-value &lt; 0.05 was considered statistically significant. Results: The results of repeated measures ANOVA regarding arterial blood oxygen saturation (SaO2) percentage showed that changes over time were significant (P &lt; 0.001). There was also a significant difference between the groups in terms of intervention effect (P = 0.004). In other words, the changes in SaO2 percentage were not the same in the two groups, and the changes in the score of the intervention group were higher than the control group. The results of repeated measures ANOVA showed that the changes in the heart rate and respiratory rate over time were significant (P &lt; 0.001). Conclusions: The quiet time protocol is effective in reducing environmental stimuli and improving physiological parameters. Therefore, the implementation of these procedures during each 8-hour shift, that includes a specific period which light, sound, and bedside stimulation is controllably reduced, is recommended as a standard of care to reduce stress and improve the growth and development of premature neonates in the NICU.

Geographical and seasonal patterns in the carbonate chemistry of Narragansett Bay, RI

This study examined geographical and seasonal patterns in carbonate chemistry and will facilitate assessment of acidification conditions and the current state of the seawater carbonate chemistry system in Narragansett Bay. Direct measurements of total alkalinity, dissolved inorganic carbon, dissolved oxygen percent saturation, water temperature, salinity and pressure were performed during monthly sampling cruises carried out over three years. These measurements were used to calculate the following biologically relevant carbonate system parameters: total pH (pHT), the partial pressure of carbon dioxide in the gas phase (pCO2), and the aragonite saturation state (ΩA). The information provided by carbonate chemistry analysis allowed for the characterization of acidification events which have the potential to disrupt the species composition and ecological functioning of coastal biological communities and threaten commercially important aquatic life. We found very robust relationships between salinity and total alkalinity (Radjusted2=0.82) and between salinity and dissolved inorganic carbon (Radjusted2=0.81) that persisted through all regions, seasons, and depth–layers with mixing of coastal waters with freshwater entering in the upper bay being an important driver on alkalinity and dissolved inorganic carbon distributions. We compared the metabolically linked calculated carbonate system parameters with dissolved oxygen (DO) saturation and found high correlation, with DO percent saturation exhibiting robust correlation with the calculated carbonate system parameters total pH (r=0.70) and with partial pressure of carbon dioxide in the gas phase (r=−0.71). Using a statistical model to correct for the confounded effects of time and space that are a common challenge in marine survey design, we found that acidification events occurred in the Northern Region of the bay, primarily during the Summer and Fall, and likely due to a combination of microbial respiration and stratification. These acidification events, especially in the Northern Region, have the potential to adversely impact aquatic life.