Investigation of the Use of Underground Cold in a Tunnel-type Ventilation System

The article analyzed the main factors affecting the productivity of birds, indicating the importance of poultry production, and also studied the widespread use of two storage systems in poultry farming. As a result of the conducted analyses, the task was set to study the optimal parameters and operating modes of the installation providing tunnel-type ventilation as a working hypothesis for warm climatic zones. The aim of the study was to increase the reliability of the cooling effect inside the building in tunnel-type ventilation installations. Based on the existing methodology, an experiment was conducted and positive results were obtained. The obtained methods have shown that it is not possible to provide the treated moisture inside the building with normal ventilation. Cooling systems ensure normal humidity. But here the use of an underground cooling channel has a wider range of redundancy. In the experimental version, egg production increased by an average of 1.26%, and the weight of eggs increased by 1.5%, and the losses of birds for 5 months of the warm period were 21 heads less.

Association of Ventilatory Disorders with Respiratory Symptoms, Physical Activity, and Quality of Life in Subjects with Prior Tuberculosis: A National Database Study in Korea

Tuberculosis (TB) survivors experience post-TB lung damage and ventilatory function disorders. However, the proportions of obstructive and restrictive ventilatory disorders as well as normal ventilation among subjects with prior TB are unknown. In addition, the impacts of ventilatory disorder and its severity on respiratory symptoms, physical activity limitations, and the quality of life in subjects with prior TB remain unclear. Subjects who participated in the Korean National Health and Nutritional Examination Survey 2007–2016 were enrolled in this study. We evaluated the impact of each ventilatory disorder and its severity on respiratory symptoms, physical activity limitations, and quality of life (measured by the EuroQoL five dimensions questionnaire [EQ-5D] index values) in subjects with prior TB. Among 1466 subjects with prior TB, 29% and 16% had obstructive ventilatory disorders and restrictive ventilatory disorders, respectively. Mild and moderate obstructive ventilatory disorders were not associated with respiratory symptoms, physical activity limitations, or EQ-5D index value compared with normal ventilation; however, severe obstructive ventilatory disorders were associated with more respiratory symptoms (adjusted odds ratio [aOR] = 13.62, 95% confidence interval [CI] = 4.64–39.99), more physical activity limitation (aOR = 218.58, 95% CI = 26.82–1781.12), and decreased EQ-5D index (adjusted coefficient = −0.06, 95% CI = (−0.12–−0.10) compared with normal ventilation. Mild restrictive ventilatory disorders were associated with more respiratory symptoms (aOR = 2.10, 95% CI = 1.07–4.14) compared with normal ventilation, while moderate (aOR = 5.71, 95% CI = 1.14–28.62) and severe restrictive ventilatory disorders (aOR = 9.17, 95% CI = 1.02–82.22) were associated with physical activity limitation compared with normal ventilation. In conclusion, among subjects with prior TB, 29% and 16% developed obstructive and restrictive ventilatory disorders, respectively. Severe obstructive ventilatory disorder was associated with more respiratory symptoms, more physical activity limitation, and poorer quality of life, while severe restrictive ventilatory disorder was associated with more physical activity limitations.

RAPID MAXILLARY EXPANSION AS THE DEFINITIVE OPTION FOR THE TREATMENT OF SLEEP APNEA / HYPOAPNEA SYNDROME IN CHILDREN. LITERATURE REVIEW

Obstructive Sleep Apnea / Hypoapnea Syndrome (OSAHS) has been described as a respiratory sleep disorder, characterized by partial or total obstruction of the upper airway, which distorts normal ventilation during sleep and 1 normal sleep patterns .Its most frequent etiology in children 2,3,4 is adenotonsillary hypertrophy , but other causes associated with syndromes and dentomaxillary anomalies are also recognized,such as maxillary compression.

The comfort parameters in indoor air of sports facilities with different ventilation regimes

Introduction: In Portugal, during COVID19pandemic, sport and fitness facilities were closed. When lockdown has been lifted, in order to prevent the spread of infection, indoor sport facilities were subject to specific regulations that limited indoor occupancy as well as manner of air ventilation. This study aims to analyze the impacts of these ventilation restrictions on indoor air comfort parameters in sport fitness facilities. Methodology: Temperature (T; ºC), relative humidity (RH; %), and carbon dioxide (CO2) were continuously monitored (41 days; spring and autumn) in four fitness centers situated in Oporto metropolitan area: two of them under normal ventilation conditions (i.e. before lockdown; NV1 and NV2) and two of them under temporary restrictions for indoor ventilations and occupancy (RV1 and RV2). Results and Discussion: Under normal ventilation conditions, T in fitness centers slightly varied (in NV1:22-25 ºC; NV2: 20-23 ºC) but in both clubs the comfort recommendations (18-25 ºC) were fulfilled. On contrary, RH were below guideline values (55-75%) in NV1 (47-54%) whereas at NV2 (66-73%) it fulfilled the recommendations. When specific health regulations took place, mean T ranges were similar in both clubs (RV1: 21-23 ºC; RV2:21-23 ºC) but they both exceeded recommended comfort levels (16-21 ºC). Mean RH were in accordance with the legislative values, but the very high temporal maxima (up to 75 and 89%) indicate the possible discomforts the that exercisers might have experienced. Concerning the CO2, the obtained results showed that indoorlevels decreased when specific health restrictions were in force (11-121%) most likely due imposed guidelines for human occupancy. Conclusions: The restrictions for ventilation and human occupancy positively impacted indoor levels of CO2. However, T and RH were on several occasions outside the recommended comfort levels, especially during group activity classes. As regular exercising in environmental conditions, such as elevated T and increased RH can cause health discomforts, these parameters should be carefully maintained within the recommended ranges even under restricted ventilation scenarios.

Impact of Ventilatory Disorders on Respiratory Symptoms, Physical Activity, and Quality of Life in Post-Tuberculosis Subjects: A National Database Study in Korea

BackgroundTuberculosis (TB) survivors experience post-TB lung damage and ventilatory function disorders. However, the proportions of obstructive and restrictive ventilatory disorders as well as normal ventilation among post-TB subjects are unknown. In addition, the impacts of ventilatory disorder and its severity on respiratory symptoms, physical activity limitations, and the quality of life in post-TB subjects remain unclear.MethodsSubjects who participated in the Korean National Health and Nutritional Examination Survey 2007–2016 were enrolled in this study. We evaluated the impact of each ventilatory disorder and its severity on respiratory symptoms, physical activity limitations, and quality of life (measured by the EuroQoL five dimensions questionnaire [EQ-5D] index values) in post-TB subjects.Results Among 1,466 post-TB subjects, 29% and 16% had obstructive ventilatory disorders and restrictive ventilatory disorders, respectively. Mild and moderate obstructive ventilatory disorders were not associated with respiratory symptoms, physical activity limitation, or EQ-5D index value compared with normal ventilation; however, severe obstructive ventilatory disorders were associated with more respiratory symptoms (adjusted odds ratio [aOR] = 5.82, 95% confidence interval [CI] = 2.80–12.10), more physical activity limitation (aOR = 92.20, 95% CI = 16.33–520.62), and decreased EQ-5D index (adjusted coefficient = -0.055, 95% CI = -0.096 – -0.013) compared with normal ventilation. Mild restrictive ventilatory disorders were associated with more respiratory symptoms (aOR = 1.95, 95% CI = 1.07–3.56) compared with normal ventilation, while moderate (aOR = 9.17, 95% CI = 1.02–82.22) and severe restrictive symptoms (aOR = 9.17, 95% CI = 1.02–82.22) were associated with physical activity limitation compared with normal ventilation.ConclusionAmong post-TB subjects, 29% and 16% developed obstructive and restrictive ventilatory disorders, respectively. Severe obstructive ventilatory disorder was associated with more respiratory symptoms, more physical activity limitation, and poorer quality of life, while severe restrictive ventilatory disorder was associated with more physical activity limitations.

The differing physiology of nitrogen and tracer gas multiple-breath washout techniques

BackgroundMultiple-breath washout techniques are increasingly being used to assess lung function. The principal statistic obtained is the lung clearance index (LCI), but values obtained for LCI using the N2-washout technique are higher than those obtained using an exogenous tracer gas such as SF6. This study explored whether the pure O2 used for the N2 washout could underlie these higher values.MethodsA model of a homogenous, reciprocally-ventilated acinus was constructed. Perfusion was kept constant, and ventilation adjusted by varying the swept volume during the breathing cycle. The blood supplying the acinus had a standard mixed-venous composition. CO2 and O2 exchange between the blood and acinar gas proceeded to equilibrium. The model was initialised with either air or air plus tracer gas as the inspirate. Washouts were conducted with pure O2 for the N2 washout or with air for the tracer gas washout.ResultsAt normal ventilation-perfusion (V̇/Q̇) ratios, the rate of washout of N2 and exogenous tracer gas was almost indistinguishable. At low V̇/Q̇, the N2 washout lagged the tracer gas washout. At very low V̇/Q̇, N2 became trapped in the acinus. Under low V̇/Q̇ conditions, breathing pure O2 introduced a marked asymmetry between the inspiratory and expiratory gas flow rates that was not present when breathing air.DiscussionThe use of pure O2 to washout N2 increases O2 uptake in low V̇/Q̇ units. This generates a background gas flow into the acinus that opposes flow out of the acinus during expiration, and so delays the washout of N2.

Accelerated ethanol elimination via the lungs

Ethanol poisoning is endemic the world over. Morbidity and mortality depend on blood ethanol levels which in turn depend on the balance between its rates of absorption and clearance. Clearance of ethanol is mostly at a constant rate via enzymatic metabolism. We hypothesized that isocapnic hyperpnea (IH), previously shown to be effective in acceleration of clearance of vapour anesthetics and carbon monoxide, would also accelerate the clearance of ethanol. In this proof-of-concept pilot study, five healthy male subjects were brought to a mildly elevated blood ethanol concentration (~ 0.1%) and ethanol clearance monitored during normal ventilation and IH on different days. IH increased elimination rate of ethanol in proportion to blood levels, increasing the elimination rate more than three-fold. Increased veno-arterial ethanol concentration differences during IH verified the efficacy of ethanol clearance via the lung. These data indicate that IH is a nonpharmacologic means to accelerate the elimination of ethanol by superimposing first order elimination kinetics on underlying zero order liver metabolism. Such kinetics may prove useful in treating acute severe ethanol intoxication.

Interference of SARS-CoV-2 with the Homeostasis of Ventilation and Perfusion in the Lung

A growing number of studies suggest that SARS-CoV-2 could interfere with homeostatic mechanisms in the lung but the implications of this possible interference have not been fully explored in the literature. In this work, we examine the consequences that can be drawn from this hypothesis according to currently available knowledge. We suggest that one such consequence is the potential disruption of normal ventilation and perfusion of lung regions that may be distant from the infection sites. Loss of ventilation might result in local alveolar hypoxia and contribute to hypoxemia, which in turn could trigger homeostatic responses that enhance blood oxygenation by redistributing pulmonary blood circulation. Sudden changes in perfusion might then lead to the development of hydrostatic edema and eventually to vascular remodeling and inflammation. Therefore, the immune response might not be the only source of the substantial inflammation observed in lung tissues of patients with severe COVID-19, as is often assumed in the literature. The balance between the homeostatic and the immune reaction in each patient could account for the observed heterogeneity of the clinical manifestations of COVID-19.

Association of infected probability of COVID-19 with ventilation rates in confined spaces: a Wells-Riley equation based investigation

BackgroundA growing number of epidemiological cases are proving the possibility of airborne transmission of coronavirus disease 2019 (COVID-19). Ensuring adequate ventilation rate is essential to reduce the risk of infection in confined spaces.MethodsWe obtained the quantum generation rate by a COVID-19 infector with a reproductive number based fitting approach, and then estimated the association between infected probability and ventilation rate with the Wells-Riley equation.ResultsThe estimated quantum generation rate of COVID-19 is 14-48 /h. To ensure infected probabolity less than 1%, ventilation rate lareger than common values (100-350 m3/h and 1200-4000 m3/h for 15 minutes and 3 hours exposure, respectively) is required. If both the infector and susceptibles wear masks, the ventilation rate ensuring less than 1% infected probability is reduced to 50-180 m3/h and 600-2000 m3/h correspondingly, which is easier to be achieved by normal ventilation mode applied in some typical scenarios, including offices, classrooms, buses and aircraft cabins.InterpretationThe risk of potential airborne transmission in confined spaces cannot be ignored. Strict preventive measures that have been widely adopted should be effective in reducing the risk of airborne transmitted infection.

Combined Xenon and Epidural Anesthesia During Surgical Correction of Joint Deformities in the Lower Extremities of Children with Cerebral Palsy

Objectives. The objective of this study is to compare different methods of combination general and regional anesthesia based on xenon.Materials and methods. Xenon anesthesia combined with epidural block was performed in 50 children with cerebral palsy aged 3–17 years. In 30 patients xenon was used to maintain anesthesia, in 20 children xenon was combined with sevoflurane. We compared the process of anesthesia, the intraoperative hemodynamic parameters and cognitive status before surgery and after it.Results. The use of xenon in all studied anesthesia methods increased the cardiac performance and was associated with a stable hemodynamic profile at all stages of anesthesia despite the depressive effect of epidural blockade on hemodynamics. Psychological testing revealed that xenon anesthesia has no negative effect on cognitive functions in children with cerebral palsy.Conclusion. Xenon anesthesia is a promising trend in anesthesia care for children with cerebral palsy. Xenon can compensate the hemodynamic depression caused by epidural anesthesia due to its cardiac stimulant property, with no neurotoxicity being a significant benefit for children with initial damage of CNS. However, anesthesia with xenon turned out to have some disadvantages. In our study, xenon showed insufficient analgesic properties, had emetic properties and was associated with spirometric abnormalities. It was more difficult to maintain normal ventilation parameters in young children when using xenon. Several adverse events were noted in the recovery period. These disadvantages can be partially reduced by using a combination of xenon and sevoflurane.