Respiratory Muscle Strength in Patients after Covid-19

Respiratory muscles (RM) are a very important part of the respiratory system that enables pulmonary ventilation. This study aimed to assess the post-COVID-19 strength of RM by estimating maximum static inspiratory (MIP or PImax) and expiratory (MEP or PEmax) pressures and to identify the relationship between MIP and MEP and the parameters of lung function. We analyzed the data of 36 patients (72% male;median age 47 years) who underwent spirometry, and body plethysmography, diffusion test for carbon monoxide (DLCO) and measurement of MIP and MEF. The median time between the examinations and onset of COVID-19 was 142 days. The patients were divided into two subgroups. In subgroup 1, as registered with computed tomography, the median of the maximum lung tissue damage volume in the acute period was 27%, in subgroup 2 it reached 76%. The most common functional impairment was decreased DLCO, detected in 20 (55%) patients. Decreased MIP and MEP were observed in 5 and 11 patients, respectively. The subgroups did not differ significantly in MIP and MEP values, but decreased MIP was registered in the second subgroup more often (18%). There were identified no significant dependencies between MIP/MEP and the parameters of ventilation and pulmonary gas exchange. Thus, in patients after COVID-19, MIP and MEP were reduced in 14 and 31% of cases, respectively. It is reasonable to add RM tests to the COVID-19 patient examination plan in order to check them for dysfunction and carry out medical rehabilitation.Copyright © 2022 Obstetrics, Gynecology and Reproduction. All rights reserved.

The inspiratory activity of respiratory center and respiratory muscles strength after COVID-19.

The respiratory pump that provides pulmonary ventilation includes the respiratory center, peripheral nervous system, chest and respiratory muscles. The aim of this study was to evaluate the activity of the respiratory center and the respiratory muscles strength after COVID-19 (COronaVIrus Disease 2019). Methods. The observational retrospective cross-sectional study included 74 post-COVID-19 patients (56 (76%) men, median age - 48 years). Spirometry, body plethysmography, measurement of lung diffusing capacity (DLCO), maximal inspiratory and expiratory pressures (MIP and MEP), and airway occlusion pressure after 0.1 sec (P0.1) were performed. In addition, dyspnea was assessed in 31 patients using the mMRC scale and muscle strength was assessed in 27 of those patients using MRC Weakness scale. Results. The median time from the COVID-19 onset to pulmonary function tests (PFTs) was 120 days. The total sample was divided into 2 subgroups: 1 - P0.1 <= 0.15 kPa (norm), 2 - > 0.15 kPa. The lung volumes, airway resistance, MIP, and MEP were within normal values in most patients, whereas DLCO was reduced in 59% of cases in both the total sample and the subgroups. Mild dyspnea and a slight decrease in muscle strength were also detected. Statistically significant differences between the subgroups were found in the lung volumes (lower) and airway resistance (higher) in subgroup 2. Correlation analysis revealed moderate negative correlations between P0.1 and ventilation parameters. Conclusion. Measurement of P0.1 is a simple and non-invasive method for assessing pulmonary function. In our study, an increase in P0.1 was detected in 45% of post-COVID-19 cases, possibly due to impaired pulmonary mechanics despite the preserved pulmonary ventilation as well as normal MIP and MEP values.Copyright © Savushkina O.I. et al., 2023.

Clinical Uses of Cuffless Blood Pressure Monitoring Devices Using Photoplethysmography as a Promising Ambulatory Telemonitoring Tool: A Systematic Review and Meta-Analysis

Introduction: As check-ups in healthcare facilities are much arduous during the pandemic including blood pressure (BP) control, an alternative is urgently needed to replace the use of disturbing cuff-based office and ambulatory BP monitoring (BPM) devices. With the advancement of telemedicine, real-time checking and reporting of blood pressure may be potentially achieved using photoplethysmography (PPG) technology in cuffless devices. Therefore, this study evaluated the accuracy of these devices compared to the cuff-based BPM devices. Method(s): This systematic review and meta-analysis was conducted based on the PRISMA 2020 guideline through multiple databases using Rayyan according to the prearranged inclusion and exclusion criteria, yielding six clinical studies to be included in the final review and analysis. Result(s): Overall fixed-effect meta-analysis of all studies (total of 319 subjects) presented small differences between cuffless and cuff-based devices, showing promising accuracy according to the current medical instrumentation guideline both in measuring systolic BP (SMD: 0.23 mmHg [95% CI: 0.07-0.39], p = 0.004;I2= 0%, p = 0.55) and diastolic BP (SMD: 0.27 mmHg [95% CI: 0.11-0.43], p = 0.0007;I2= 39%, p = 0.14). Discussion(s): PPG itself is a noninvasive technology, consisting of an infrared-emitting light source and a photodetector to measure the blood-reflected light intensity. Despite its ease in equipment, it measures BP accurately without being influenced by various positions and activities. Moreover, the data can be accessed real-time by both users and healthcare providers. Conclusion(s): In summary, cuffless PPG BPM devices have the potential in becoming a telemonitoring device for ambulatory patients for its accuracy. Its presence may be the answer to current restriction towards healthcare access during the COVID-19 pandemic. Therefore, in order to further confirm our findings, more clinical studies with various settings are encouraged to be held.

The inspiratory activity of respiratory center and respiratory muscles strength after COVID-19.

The respiratory pump that provides pulmonary ventilation includes the respiratory center, peripheral nervous system, chest and respiratory muscles. The aim of this study was to evaluate the activity of the respiratory center and the respiratory muscles strength after COVID-19 (COronaVIrus Disease 2019). Methods. The observational retrospective cross-sectional study included 74 post-COVID-19 patients (56 (76%) men, median age - 48 years). Spirometry, body plethysmography, measurement of lung diffusing capacity (DLCO), maximal inspiratory and expiratory pressures (MIP and MEP), and airway occlusion pressure after 0.1 sec (P0.1) were performed. In addition, dyspnea was assessed in 31 patients using the mMRC scale and muscle strength was assessed in 27 of those patients using MRC Weakness scale. Results. The median time from the COVID-19 onset to pulmonary function tests (PFTs) was 120 days. The total sample was divided into 2 subgroups: 1 - P0.1 <= 0.15 kPa (norm), 2 - > 0.15 kPa. The lung volumes, airway resistance, MIP, and MEP were within normal values in most patients, whereas DLCO was reduced in 59% of cases in both the total sample and the subgroups. Mild dyspnea and a slight decrease in muscle strength were also detected. Statistically significant differences between the subgroups were found in the lung volumes (lower) and airway resistance (higher) in subgroup 2. Correlation analysis revealed moderate negative correlations between P0.1 and ventilation parameters. Conclusion. Measurement of P0.1 is a simple and non-invasive method for assessing pulmonary function. In our study, an increase in P0.1 was detected in 45% of post-COVID-19 cases, possibly due to impaired pulmonary mechanics despite the preserved pulmonary ventilation as well as normal MIP and MEP values.Copyright © Savushkina O.I. et al., 2023.

Respiratory function and symptoms after acute COVID-19 infection in children and adolescents

Introduction/Aim: Significant long-term effects on both symptomatology and respiratory function have been recognised in adult populations after COVID-19 infection, termed 'Long COVID'. These have caused loss of productivity and increased need for healthcare services. This study aimed to measure symptoms and lung function in children and adolescents after acute COVID-19 infection Methods: Between June 1 and 31 October 2021 there were 144 children admitted to hospital across the Sydney Children's Hospital Network, Australia. Of these, 63 children were referred to the respiratory clinic with symptoms of ongoing cough, shortness of breath and fatigue, 3-6 months post COVID infection. 20 of these children performed reliable lung function. For these children, body plethysmography and double diffusion testing were performed within 3-6 months of their infection. The Liverpool respiratory questionnaire and PROMIS paediatric sleep questionnaires were also administered. Result(s): Of the 20 patients tested, 7 had COVID pneumonitis requiring hospitalisation during the acute illness. 6 of the 20 patients had significant persistent symptoms as measured by the Liverpool respiratory questionnaire, while none of the children had any significant sleep symptoms. All children had preserved spirometry within normal limits. Of note, 2 children with persistent respiratory symptoms had DLNO/DLCO ratio >1.15, suggesting pulmonary vascular disease. The same two children who had elevated DLNO / DLCO had high ventilator equivalents on CPET testing suggesting increased physiological dead space ventilation. Despite this, their peak aerobic capacity was within normal limits. There were no significant differences between the alpha and delta cohorts or between children treated at home vs those requiring hospitalisation during their infection. Conclusion(s): COVID-19 may cause long-lasting effects in children. In this cohort, all children maintained spirometry results within normal limits despite significant symptoms impacting daily activities. Double diffusion testing may shed some light on lung changes leading to persistent symptomatology after COVID infection.

Evaluation of lung inflammation using Exhaled breath condensate in patients with post-COVID syndrome

Introduction: The term "post-COVID syndrome" encompasses a wide range of clinical conditions following SARSCOV2 infection. Whether post-COVID syndrome can be associated with a prolonged inflammatory and immune response is still unknown. Exhaled Breath Condensate (EBC) pH has been recognized as a robust marker of lung inflammation in various diseases (Kharitonov et al. Chest 2006;130(5):1541-46). However, evidences on the role of EBC pH in diagnosing lung inflammation in post-COVID syndrome are still lacking. Aims and objectives: We aimed to investigate EBC pH in patients suffering from post-COVID syndrome. Method(s): We enrolled 10 patients hospitalized with acute respiratory failure and COVID-19 pneumonia. We performed a complete follow up after 3 months (T1) and 6 months (T2) from discharge. Each visit included routine blood tests, arterial blood gas analysis, 6 minute walking test and body plethysmography. Finally, bronchial and alveolar EBC pH were collected at the end of each visit. Result(s): Alveolar EBC pH was significantly lower at T1 compared with T2 samples (p= 0.0007). Moreover, in T1 analysis, we found a less acid pH in bronchial EBC compared to the alveolar one (p=0.003). Alveolar and bronchial EBC did not differ at T2, as well as bronchial EBC from T1 to T2. Serum inflammatory biomarkers did not differ from T1 to T2 analysis. Finally, alveolar EBC was directly correlated with Neutrophil-Lymphocyte ratio (R=0.71, p=0.02). Conclusion(s): Alveolar EBC pH is a useful non-invasive tool to characterize and monitor lung inflammation in patients with post-COVID syndrome. Furthermore, no other serum biomarker seems to be sensitive enough to identify residual phlogosis after COVID-19 disease.

Respiratory function and symptoms after acute COVID-19 infection in children and adolescents

Introduction: Significant long-term effects on both symptomatology and respiratory function have been recognised in adult populations after COVID-19 infection, termed 'Long COVID'. These have caused loss of productivity and increased need for healthcare services. This study aimed to measure symptoms and lung function in children and adolescents after acute COVID-19 infection. Method(s): Clinical follow up, body plethysmography, and double diffusion testing were performed on 18 children and adolescents (age 7-17 years) within 3-6 months of their infection. The Liverpool respiratory questionnaire and PROMIS paediatric sleep questionnaires were also administered. 5 patients were infected with the alpha variant, while 13 had the delta variant. Of those with the delta variant, 7 had COVID pneumonitis requiring hospitalisation during their acute illness. None had been vaccinated against COVID-19. Result(s): Most children recovered well with minimal residual symptoms, and maintained lung function within normal limits. However, 3 of the 18 children had ongoing symptoms that impacted their day-to-day activities. These included fatigue, exercise limitation, sleep impairment and persistent post-viral cough. Of these, 2 children had abnormalities on double diffusion testing, despite normal spirometry. There were no significant differences between the alpha and delta cohorts or between children treated at home vs those requiring hospitalisation. Conclusion(s): 'Long COVID' also affects paediatric populations, particularly in terms of ongoing fatigue and exercise limitation. Double diffusion testing may shed some light on lung changes leading to persistent symptomatology after COVID infection.

Role of 1-minute sit-to-stand in the diagnosis of Long COVID

Introduction: Current literature on 1-minute sit-to-stand (1-STS) role in COVID-19 focuses on its ability to predict need for hospitalization or home discharge, but not Long COVID diagnosis where gaps in knowledge are recognized in NICE Long COVID guidelines. Aim(s): Assess 1-STS role in Long COVID definition. Method(s): Prospective ongoing cohort of post COVID-19 patients referred to body plethysmography at a university tertiary hospital. Result(s): Thirty-two patients were analyzed (53.1% male, mean 54 years-old), of whom 15 (46.9%) fulfilled Long COVID criteria. Of these, the most common symptoms were insomnia and/or excessive fatigue (n=8, 53.3%) and dyspnea (n=4, 26.7%). Long COVID patients had higher body mass index (29.7+/-6.0 vs 26.2+/-3.3Kg/m2;p=0.043). Patients with and without Long COVID were similar regarding age (p=0.827), hospitalization due to COVID-19 (p=0.811) or smoking history (p=0.234). Parameters of the 1-STS most associated with Long COVID were lower heart rate (HR) at 30' (89.1+/-14.0 in Long COVID vs 105.9+/-14.3bpm for no Long COVID criteria;p=0.002) and at 60' (99.3+/-24.0 vs 120.8+/-13.9bpm;p=0.004), as well as lower SpO at 60' (94.5+/-4.4 vs 97.1+/-1.6%;p=0.046). The parameter with the highest predictive power for Long COVID was HR at 60'(AUC=0.808;p=0.003), and when <80bpm revealed 90% sensitivity and 99% specificity in this study population. Decline of SpO during 1-STS was tendentially greater in those with Long COVID, yet without significance (-2.7+/-4.4 vs -0.8+/-1.4%;p=0.093). Conclusion(s): Lower final SpO and HR on 1-STS, as well as 30' HR, were associated with the occurrence of Long COVID. Final HR<80 bpm in a post COVID-19 setting might be the best 1-STS predictor of Long COVID.

Standardized 3- and 12-months imaging and clinicalfunctional pulmonary follow-up in patients hospitalized for COVID-19

Introduction: Natural history of COVID-19 is yet unknown. A standardized follow-up may allow evaluating different patterns of COVID-19 evolution. AIM: To describe imaging and clinical-functional pulmonary data at 3- (T3) and 12-months (T12) follow-up in COVID19 patients. Method(s): COVID-19 patients discharged from Pisa University Hospital, Italy, from March to September 2020 were evaluated. Expert radiologists qualitatively assessed the evolution of COVID-19 pneumonia CT signs (PS) (baseline acute disease vs. T3) by using an original coding system. A chest CT at T12 was performed only in patients who had persistent PS at T3. Both at T3 and T12, all the patients underwent spirometry, plethysmography, DLCO and pulmonary visit. Result(s): Among 307 discharged patients, 57% and 44.3% were followed up at T3 and T12, respectively, while 12.4% died within T3. Followed patient's characteristics were: 62.9% men;median age 60.3 yrs;11.3% smokers and 30.6% ex-smokers;mean BMI 29.1 kg/mq;43.8% had 1+ comorbidities;median hospitalization 15 days;17.4% stayed 3+ days in ICU. At T3, 52.1% of patients showed resolution of PS, 82.8% had normal spirometry and 76.7% normal DLCO. Among patients with persistent PS at T3 (47.9%), 59.4% showed stability or improvement and 39.1% resolution of PS at T12. 31.6% had persistent PS at T12. An increased proportion of patients with normal lung function was observed at T12, but 5.6% and 20.4% had a restrictive pattern and reduced DLCO, respectively. Conclusion(s): About a third of patients show persistence of PS and about a fifth has DLCO abnormalities at 12- months from the acute COVID-19. Further follow-up is planned for these patients.

Phenotyping dyspnea in patients suffering from postCOVID syndrome

Introduction: Post COVID dyspnea is considered one of the most troublesome symptoms, even after the acute phase of COVID-19 disease. Few data are currently available describing features post-COVD dyspnea. Aims and objectives: To phenoype dyspnea in patients with post-COVID syndrome. Method(s): We enrolled 309 patients who suffered from COVID-19 disease. All patients were screened with a complete blood workup, body plethysmography, arterial blood gas analysis and 6 minute walking test (6MWT). Moreover, 80 patients underwent chest Computed Tomography (CT) according to their clinical status. Result(s): Half of the enrolled patients (51.8%) reported residual dyspnea, both at rest and during their daily activities. Among them, 56.7% of patients had also dyspnea as the first symptom at COVID-19 onset (p=0.04). Patients referring dyspnea showed a lower PaO2 (p=0.02) and an increased pre-post test BORG scale difference (p<0.0001), without significant desaturations (>=3%) during the 6MWT. We also found a decreased 6 minute walking distance in these patients (p=0.004), as well as a reduction in diffusing capacity (DLCO, p=0.0005). After performing a multivariate logistic regression, only DLCO resulted to be statistically significant (OR=0.97, p=0.03). Moreover, among our patients who performed chest CT, 76.2% of them were found to have residual abnormalities such as ground glass opacities (50%), lung scars (26.2%) and parenchymal consolidations (12.5%). Conclusion(s): DLCO reduction is the most influencing factor for the development of post-COVID dyspnea. Moreover, PaO2, 6MWT parameters and chest CT alterations can also increase the breathing discomfort in these patients.

Distribution of sequelae in post-covid patients according to previous need of respiratory support

Introduction: "Long COVID" is defined by the persistence of symptoms after 4-12 weeks from COVID-19 disease. Data comparing different clinical phenotypes according to COVID-19 severity are still scanty. Aims and objectives: We aimed to identify different clinical phenotypes of post-COVID syndrome according to the level of respiratory support used. Method(s): We enrolled 309 patients who previously suffered from COVID-19 disease. All patients performed routine blood tests, arterial blood gas analysis, 6 minute walking test and body plethysmography. Then, we assigned each patient to a "severity group" according to the respiratory support needed during COVID-19 disease. Severity group 0: no respiratory support needed Severity group 1: oxygen only Severity group 2: positive airway pressure (CPAP or NIV) Severity group 3: Invasive Mechanical Ventilation (IMV) Results: Patients belonging to Group 0 experienced less fatigue (p=0.004) and mood disorders (p=0.007) compared to the other groups. Group 0 and 3 reported less frequently insomnia (p<0.0001). Hospitalized patients developed sleep and mood disorders during hospitalization due to several factors (fear, acoustic/visual triggers ect.). Patients who underwent IMV, instead, were completely sedated for the entire course of the acute phase of the disease, not being exposed to these triggers. Among blood markers, only Galectin-3 (p=0.004) and IL6 (p=0.004) had significant lower serum concentrations in patients belonging to Group 0, confirming their lower inflammatory status Conclusion(s): Awake hospitalization seems to deeply affect post-COVID sequelae in several patients.

Lung function variability in one year after COVID-19 pneumonia

The SARS-CoV-2 virus causes pneumonia which can result in lung function (LF) impairment. Impaired LF shortly after the disease is not commonly observed, but the LF substantially fluctuates even when its value remains within the limits of the norm. The aim of the study was to determine the variability scope of LF during the first year after COVID-19 pneumonia. Material(s) and Method(s): LF measurements (spirometry, body-plethysmography, transfer factor) were conducted up to 1 month, 3, 6, and 12 months after hospitalization in a group of consecutive patients recovered from moderate to severe COVID-19 pneumonia requiring hospitalization. The coefficient of variation (CV) was calculated to assess the stability of LF. Result(s): 113 patients were included, with a lung involvement median of 40% (IQR:30-60%). Shortly after hospitalization, we detected 3.5% airway obstructions, 12.4% restrictions, and 26.5% lung transfer factor impairments. During one year significant changes were observed in lung volumes but not flow indices. The most pronounced improvements were observed in lung transfer factor (TLco) and they were associated with volume changes (VA), but not Kco improvements (figure 1). Stable LF (CV<4%) was observed only in 21% of patients. Conclusion(s): Impaired LF shortly after COVID-19 was detected in a quarter of patients with significant improvement in the next months. However, lung function remained unstable in the majority of examined patients.

ALPINE: Improving Remote Heart Rate Estimation using Contrastive Learning

Heart rate (HR) is a crucial physiological indicator of human health and can be used to detect cardiovascular disorders. The traditional HR estimation methods, such as electrocardiograms (ECG) and photoplethysmographs, require skin contact. Due to the increased risk of viral in- fection from skin contact, these approaches are avoided in the ongoing COVID-19 pandemic. Alternatively, one can use the non-contact HR estimation technique, remote photo- plethysmography (rPPG), wherein HR is estimated from the facial videos of a person. Unfortunately, the existing rPPG methods perform poorly in the presence of facial deformations. Recently, there has been a proliferation of deep learning networks for rPPG. However, these networks require large-scale labelled data for better generalization. To alleviate these shortcomings, we propose a method ALPINE, that is, A noveL rPPG technique for Improving the remote heart rate estimatioN using contrastive lEarning. ALPINE utilizes the contrastive learning framework during training to address the issue of limited labelled data and introduces diversity in the data samples for better network generalization. Additionally, we introduce a novel hybrid loss comprising contrastive loss, signal-to-noise ratio (SNR) loss and data fidelity loss. Our novel contrastive loss maximizes the similarity between the rPPG information from different facial regions, thereby minimizing the effect of local noise. The SNR loss improves the quality of temporal signals, and the data fidelity loss ensures that the correct rPPG signal is extracted. Our extensive experiments on publicly available datasets demonstrate that the proposed method, ALPINE outperforms the previous well-known rPPG methods. © 2023 IEEE.

Stress Data Collection and Analysis Using 'Mind Scale' with the Post-Covid World

In this paper, stress data collection and analysis using 'Mind Scale™' is proposed. A fingertip pulse wave sensor module is utilized along a smartphone application. Biological signals such as pulse, voice and facial expression are analyzed with questionnaire and managed in the cloud. With the post-covid world, this system helps us to detect our mental health condition for new lifestyle. © 2023 IEEE.

Respiratory functions in the follow-up of children with COVID-19 infection

Introduction or Background: The long-term effects of COVID-19 infection on the respiratory system in children are not yet known. Aims and Objectives: To determine the long-term effects of COVID-19 infection on the respiratory system of children by evaluating pulmonary function tests. Method(s): In this multicenter study, COVID-19 PCR positive children(>=6years) were evaluated prospectively with pulmonary function tests(spirometry, plethysmography and CO diffusion) at 3rd and 6th months follow-up. The results were evaluated retrospectively based on clinical symptoms, physical examination findings, radiological and laboratory tests of the patients in the acute phase of the infection. Result(s): At 3rd month evaluation of 270 COVID-19 PCR positive pediatric patients, mean FEV1 96.85+/-16.84%,FVC 96.06+/-16.84% were found;at 6th month, mean FEV1 100,03+/-15.98%,FVC 100.62+/-16.87. At the 3rd month, statistically significant differences were found between FEV1<80%(n:28),FEV1>80%(n:242) groups due to the presence of additional diseases(p<0.001),having respiratory(p=0.006) and cardiovascular(p=0.004) system pathological examination findings, interlobular septal thickening(p=0.020) on thorax CT, high level of CRP(p=0.032),IL6(p=0.048),ferritin(p=0,020) during the infection period. Having COVID-19 pneumonia was found to be non-effective on spirometric test results. No difference was found between the 3rd and 6th month spirometry results of the same patient. Conclusion(s): After recovery of COVID-19 infection, children who have additional diseases, and pathological examination and radiological findings during the infection period, may have functional respiratory changes;so they should be monitored with pulmonary function tests.

A V/Q SPECT/CT Study on Whether Persistent Reduction in Lung Diffusion Capacity after COVID-19 is Related to Restrictive or Vascular Lung Disease?

Aim/Introduction: Many patients have reduced pulmonary diffusion capacity (DLco) after COVID-19. We assessed whether this is due to a post-COVID restrictive lung disease and/or pulmonary vascular disease. Material(s) and Method(s): In total 67 patients diagnosed with COVID-19 at our hospital in 2020 were included across three severity groups: 12 mild - not admitted to hospital, 40 moderate - admitted to hospital without intensive care unit (ICU) admission, and 15 severe - with ICU admission. At 5-months followup after SARS-CoV-2 diagnosis, lung function (spirometry, body plethysmography, DLco), high-resolution CT of the lungs (HRCT), and ventilation/perfusion (V/Q) SPECT/CT were conducted. Result(s): DLco was reduced in 42% of the patients (mild 17%, moderate 40% and severe 71%);both prevalence and degree depended on clinical severity group and was usually part of a restrictive pattern with reduced TLC. Reduced DLco was associated with ground-glass opacification and pulmonary fibrosis found on HRCT and matched V/Q SPECT defects, but not with mismatched perfusion defects on V/Q SPECT/CT. Conclusion(s): The severity-dependent decline in DLco observed 5 months after COVID-19 is related to restrictive lung disease but not to pulmonary vascular disease.

Contactless blood oxygen estimation from face videos: A multi-model fusion method based on deep learning.

Blood Oxygen ( SpO 2 ), a key indicator of respiratory function, has received increasing attention during the COVID-19 pandemic. Clinical results show that patients with COVID-19 likely have distinct lower SpO 2 before the onset of significant symptoms. Aiming at the shortcomings of current methods for monitoring SpO 2 by face videos, this paper proposes a novel multi-model fusion method based on deep learning for SpO 2 estimation. The method includes the feature extraction network named Residuals and Coordinate Attention (RCA) and the multi-model fusion SpO 2 estimation module. The RCA network uses the residual block cascade and coordinate attention mechanism to focus on the correlation between feature channels and the location information of feature space. The multi-model fusion module includes the Color Channel Model (CCM) and the Network-Based Model(NBM). To fully use the color feature information in face videos, an image generator is constructed in the CCM to calculate SpO 2 by reconstructing the red and blue channel signals. Besides, to reduce the disturbance of other physiological signals, a novel two-part loss function is designed in the NBM. Given the complementarity of the features and models that CCM and NBM focus on, a Multi-Model Fusion Model(MMFM) is constructed. The experimental results on the PURE and VIPL-HR datasets show that three models meet the clinical requirement(the mean absolute error ⩽ 2%) and demonstrate that the multi-model fusion can fully exploit the SpO 2 features of face videos and improve the SpO 2 estimation performance. Our research achievements will facilitate applications in remote medicine and home health.

Functional and quantitative computed tomographic changes in the bronchopulmonary system in patients who have undergone COVID-19

Introduction. COVID-19 is a highly contagious infectious disease caused by the novel coronavirus SARS-CoV-2. After the acute phase and discharge from the hospital, convalescent people continue to have respiratory symptoms, changes in pulmonary function (PF) and indicators of chest computed tomography (CT). Aim. To evaluate changes in PF and quantitative CT data in patients after severe coronavirus pneumonia. Materials and methods. A cross-sectional observational study was conducted: 55 patients (including 28 men, aged 32–78 years) with a diagnosis of “lung interstitial process due to a coronavirus infection” were examined. All patients underwent a study of PF (spirometry, body plethysmography, measurement of the diffusion lung capacity: DLCO ) in the interval of 24–305 days after discharge from the hospital. CT scan of the chest was performed simultaneously with the functional examination (±30 days), the parameters were calculated: ground glass areas, functional lung tissue volume (FV), affected tissue volume (AV), CovidQ (AV/FV ratio). Results. A decrease in DLCO was found in 28 patients. Restrictive disorders – in 13 patients, obstructive disorders – in 2 patients. At the time of the CT examination, all patients had residual changes in both lungs of varying severity. Functional parameters (FVC, TLC and DLCO ) were statistically significantly correlated with the CT data. Conclusion. During the recovery period in patients after COVID-19, lung structural changes, according to CT scans, persist for at least 3 months. Pulmonary ventilation indicators in most patients normalize during this time, half of the patients retained a decrease in diffusion lung capacity. © 2022, Remedium Group Ltd. All rights reserved.

Adenosine A2A Receptor (A2AR) Agonist Apadenoson Promotes Survival in K28-hACE2 Mice and Syrian Hamsters Infected with Sars-CoV-2

Purpose: To determine if Apadenoson or Regadenoson has a therapeutic effect in attenuating hyper-inflammation and improving survival rate in K18-hACE2mice or Syrian hamsters infected with SARS-CoV-2. Method(s): 6-8 weeks old male K18-hACE2mice were divided into Control group that received vehicle;Test group 1 that received the drug (Apadenoson or Regadenoson) 24hrs prior to challenge with SARS-CoV-2;and Test Group 2 (Drug-delay), that received the drug with a 5 hr delay post-viral infection (n=6/grp). Viral dose was 1250 PfuHong Kong/VM20001061/2020 delivered via intranasal route. Drug was delivered subcutaneously using 1007D ALZET pumps. 6 weeks old Syrian hamsters were divided into Control group that received Vehicle and Virus (n=4) and 2 test groups (n=5/group) that received Apadenoson+Virus and Regadenoson+Virus. Drugs were delivered by 2ML2 ALZET pumps (4ug/kg/hr). Hamsters were inoculated intratracheally with 750PFU SARS-CoV-2 WA1 strain prior to treatment. Mice were weighed and clinical scores recorded daily. Bronchoalveolar lavage fluid (BALF) and serum were collected along with lungs. Plethysmography was done on days 0, 2, 4 and 7. Result(s): Apadenoson administered post-infection was efficacious in decreasing weight loss, improving clinical score, and increasing the survival rate in K18-hACE2 mice, i.e. 50% survival was observed at Day 5 and at Day 7 post-infection for drug given before or after infection respectively. Apadenoson given post-infection improved the histopathology that was observed in the vehicle control group, decreased pro-inflammatory IL-6, IFN-gamma, MCCP-1, MIP-1beta, IP-10, and Rantes in serum, increased anti-inflammatory Ang1-7 levels, and decreased monocytes in BALF. 42% of mice that received Regadenoson pre-challenge survived infection compared to 6.25% in the vehicle or Drug delay (drug given post-infection) groups. Viral titers in the lungs of Regadenoson-treated mice were found decreased. Treatment also significantly decreased CD4+, CD8+T cells, eosinophils, and neutrophils in BALF. Plethysmography, in hamsters, showed significant improvement of pulmonary function parameters, Rpef and PenH, following treatment with Apadenoson given post-infection. Apadenoson cleared the virus from BALF and maintained Ang1-7 levels. Both drugs decreased plasma IFN-gamma levels. Conclusion(s): Treatment with Apadenoson attenuated inflammation, improved pulmonary function, decreased weight loss, and enhanced survival rate following infection with SARS-CoV-2 virus. The results demonstrate the translational significance of Apadenoson in the treatment of COVID-19.

RESPIRATORY FUNCTION IN PATIENTS WITH HIV POSTINFECTION BY COVID-19

SESSION TITLE: Post-COVID-19 Outcomes SESSION TYPE: Rapid Fire Original Inv PRESENTED ON: 10/19/2022 11:15 am - 12:15 pm PURPOSE: Alterations in lung function may occur in patients with HIV and who were infected with SARSCoV2. In order to describe this characteristics we created the following groups: Group (1) HIV (+) SARS-COV-2 (+), Group (2) HIV (+) SARS-COV-2 (-), Group (3) HIV (-) SARS-COV2 (+), Group (4) HIV (-) SARS-COV-2 (-). METHODS: In this prospective, longitudinal cohort we included patients with infection with SARS-CoV-2 ( RT- PCR test o Antigen Testing positive) who agreed to participate in the study. Spirometry, diffusing capacity of carbon monoxide (DLCO), body plethysmography, and 6-minute walk test (6MWT) were performed to assess lung function 3 to 6 months after SARS-CoV2 infection, clinical and laboratory characteristics were assesed. We performed descriptive statistics including means and standar deviations for normally distributed continous variables, medians and interquartile ranges for non-parametric distributions, and proportions for categorical variables. The comparisons between groups were made using Fisher´s exact test and Mann-Whitney U for categorical and continous variables respectively. RESULTS: During the between April 2021-February 2022, a total of 104 patients were included. Group (1)44 patients (14 were hospitalized), Group (2)19 patients, Group (3)26 patients (16 were hospitalized), Group (4)15 patients. Hypertension was higher in the Group HIV (-) SARS-COV-2 (+). We didn´t find differences in lung pulmonary function (Spirometry, DLCO, body plethysmography or 6MWT between groups). Spirometry results: FEV1/FVC % Predicted Group 1: 58.0 [25.5, 74.0], Group 2:42.5 [19.5, 65.5], Group 3: 55.0 [38.5, 80.5], Group 4: 35.0 [19.0, 68.5], HIV(+)/HIV(-) p-value: 0.43. DLCO% predicted Group 1: 82.7 [71.5, 90.0], Group 2: 86.7 [76.8, 96.3], Group 3: 85.6 [76.8, 91.6], Group 4: 88.3 [85.7, 98.6], p: 0.199. Total lung capacity (TLC) % of predicted, Group 1: 101 [88.8, 109], Group 2: 99.5 [97.0, 112], Group 3: 102 [94.3, 112], Group 4: 111 [103, 115], p: 0.105. 6MWT: Group 1: 566 [529, 604], Group 2: 595 [548, 622], Group 3: 548 [493, 604], Group 4: 593 [547, 630], p: 0.702. CONCLUSIONS: To our knowledge, this is the first study to characterize pulmonary function in ill COVID-19 survivors with HIV. Our results suggest not difference between the lung function tests performed in patients coinfected with HIV and SARS-CoV 2 compared to patients infected with SARS-CoV2 HIV (-). Limitations, not pre-testing pulmonary function. Inclusion of a greater number of HIV (-) patients who required hospitalization. CLINICAL IMPLICATIONS: Beyond the effects of SARS-CoV2 on HIV outcomes, it is essential to examine whether HIV has an impact on susceptibility to COVID-19 or if it will generate changes that lead to increased sequelae in these patients. It is well known that patients with HIV may be at increased risk of lung function test abnormalities due to the infection itself, as well as some additional exposures. DISCLOSURES: No relevant relationships by Olivia Briceño No relevant relationships by GUSTAVO CASAS no disclosure on file for Mauricio Gonzalez Navarro;No relevant relationships by Alejandro Juárez Díaz No relevant relationships by William C. Lara-Vazquez No relevant relationships by María Isabel León Rodríguez No relevant relationships by JOSE CHRISTIAN RODRIGUEZ HERNANDEZ No relevant relationships by Gonzalo Salgado