Reduction In Airflow Research Articles

A preliminary study on the relationship between sleep, depression and cardiovascular dysfunction in a 4 sample population

BackgroundMajor Depressive Disorder (MDD) has been linked in the literature to poorer prognosis in patients with cardiovascular dysfunction, although the mechanisms of this relationship remain unclear. Underlying Sleep Disordered Breathing (SDB) serves as a potential candidate to explain this effect due to its downstream effects on inflammatory activation and decreased nitric oxide (NO) bioavailability, both of which have been shown to contribute to the pathophysiology of both MDD and cardiovascular disease (CVD).MethodsThis study utilizes overnight polysomnography and an inflammation panel to examine the links between cardiovascular dysfunction and sleep difficulties in control participants and patients diagnosed with SDB only, MDD only, and both SDB and MDD.ResultsResults demonstrate a strong positive relationship between sleep dysfunction and the nitric oxide synthesis inhibitor Symmetric Dimethyl Arginine (SDMA) in the MDD-only cohort, suggesting a link between SDMA-mediated NO dysregulation and CVD pathogenesis in individuals with MDD. Additionally, hypopneas, a form of sleep impairment characterized by partial reduction of airflow, were found to play a significant role in the relationship between SDB and cardiovascular dysfunction in MDD-only patients.ConclusionsResults of this study demonstrate the need for widespread screening for SDB in MDD populations to detect predisposition to CVD, and also offer SDMA as a new potential target for CVD treatment in individuals with MDD.

Effect of septal deviation on nasomaxillary shape: A geometric morphometric study.

Nasal cavities in their primitive stage communicate with the oral cavity until the 8th week of intrauterine life where the posterior palate initiates its development. Hence, starting from the initial growth phases, a significant connection lays between the nasal structures and the maxillary bone and witnessing key functional roles, among which the respiration. Proper nasal breathing has been proven to be a crucial factor for the maturity of the craniofacial complex, and obstruction of the respiratory airway due to nasal septum deviation can generate clinically significant reduction of the nasal airflow. This situation will imply irreversible repercussions that hinders the harmonious development of the craniofacial complex. In order to understand such potential impacts of septal deviation, our first objective was to materialize the relation between septum deviation, and both nasal cavity and maxillary structures. For the second objective, we used Procrustes analysis to assess the shape variation of these two anatomical regions, the bivariate plots of Principal Components to evaluate their shape space, and a two-block Partial Least Square (PLS) to explore their covariation. We analysed, in this cross-sectional study, 62 posteroanterior cephalometric radiographs of adult subjects from both sexes (23males, 39 females; mean age 25.3years) collected from the database of the Department of Orthodontics at Lebanese University. Landmarks were plotted and variables were calculated and divided into nasal septum, nasal cavity and maxillary ones. The sample was further divided into two groups based on septal deviation severity (a septal deviation is considered minor if <6). The results suggested that nasal septum deviation was correlated to reduced nasal cavity area and a reduced maxillary area. Moreover, the comparison of the two groups concluded that the difference between all variables was statistically significant with higher scores in the minor septal deviation group. These findings were corroborated with the shape analysis where the mean centroid size of nasal cavity and that of the maxilla in the group of reduced septal deviation were significantly greater than those of the group with increased angle of deviation. Results of PLS analysis concluded to a strong covariation between nasal septum and nasomaxillary complex. These conclusions support the early septoplasty in growing patients as a solution to redirect the normal course of growth and re-establish a good function of the nasomaxillary complex.

Nasal Mucociliary Clearance in Prolonged Tracheostomy Patients: A Prospective Case-Control Study.

Prolonged tracheostomy bypasses the upper airways leading to absence or reduction of nasal airflow. This altered nasal physiology not only impairs olfaction but also may cause mucociliary dysfunction and consequent nasal crusting and rhinosinusitis.To objectively evaluate the extent of nasal mucociliary impairment in patients with prolonged duration of tracheostomy.This is a prospective case-control study done in a tertiary care center wherein the nasal mucocilary function was assessed by saccharin test in patients who were tracheostomized for a period of more than 4weeks and the saccharin transit time (time taken to appreciate the sweet taste after endoscopic insertion of saccharin pellet on anterior end of inferior turbinate) was compared by the same test in age and sex matched healthy individuals. The saccharin transit time in the two groups was statistically analyzed using student t-test. Mean saccharin transit time in 30 patients with prolonged tracheostomy was 934.97s with a standard deviation of 75.95s whereas in 30 controls, the meantime was 447.4s with a standard deviation of 63.22s, which was statistically significant (p < 0.001). Conclusion Prolonged duration of tracheostomy leads to impaired nasal mucociliary clearance, which in turn could cause chronic rhinosinusitis.

The Efficacy of Lingual Laser Frenectomy in Pediatric OSAS: A Randomized Double-Blinded and Controlled Clinical Study.

This randomized, double-blind and controlled clinical trial investigates how a diode laser lingual frenectomy can improve obstructive sleep apnea syndrome (OSAS) in pediatric patients. Background: Several authors have shown that a short lingual frenulum causes a reduction in incoming air flow and the relationship between OSAS and a short lingual frenulum. Methods: Thirty-two pediatric patients were equally randomly divided into a Study Group (SG) and a Control Group (CG). On each SG patient a polysomnography 1 (PSG1) and a lingual frenectomy were performed using a diode laser via Doctor Smile Wiser technology, power 7 W. After three months, a new polysomnography (PSG2) was performed to evaluate the lingual frenectomy efficacy in pediatric patients. The pain was assessed by a numerical rating scale (NRS) before and after surgery. The CG followed the same protocol without a lingual frenectomy but myofunctional and speech therapy were conducted to qualitatively and quantitatively improve the lingual functionality. In the SG, eight subjects (50%) had severe OSAS and eight had moderate (50%) while in the CG, three subjects had severe OSAS (18.8%) and thirteen had moderate (81.2%). Results: In the SG, 93.8% were classified as mild OSAS and 6.2% as moderate. In contrast, in the CG, 18.75% were classified as mild OSAS, 62.5% as moderate and 18.75% as severe. Conclusion: The study demonstrates how a lingual laser frenectomy can improve OSAS in pediatric patients.

Novel antimicrobial materials designed for the 3D printing of medical devices used during the COVID-19 crisis

Purpose This study aims to describe the preparation of antimicrobial material usable in 3D printing of medical devices. Despite the wealth of technological progress at the time of the crisis caused by SARS-CoV-2 virus: Virus that causes current Pandemic situation (COVID-19), the global population had long been exposed beforehand to an acute absence of essential medical devices. As a response, a new type of composite materials intended for rapid prototyping, based on layered silicate saponite (Sap), antimicrobial dye phloxine B (PhB) and thermoplastics, has been recently developed. Design/methodology/approach Sap was modified with a cationic surfactant and subsequently functionalized with PhB. The hybrid material in powder form was then grounded with polyethylene terephthalate-glycol (PETG) or polylactic acid (PLA) in a precisely defined weight ratio and extruded into printing filaments. The stability and level of cytotoxicity of these materials in various physiological environments simulating the human body have been studied. The applicability of these materials in bacteria and a yeast-infected environment was evaluated. Findings Ideal content of the hybrid material, with respect to thermoplastic, was 15 weight %. Optimal printing temperature and speed, with respect to maintaining antimicrobial activity of the prepared materials, were T = 215°C at 50 mm/s for PETG/SapPhB and T = 230°C at 40 mm/s for PLA/SapPhB. 3 D-printed air filters made of these materials could keep inner air flow at 63.5% and 76.8% of the original value for the PLA/SapPhB and PETG/SapPhB, respectively, whereas the same components made without PhB had a 100% reduction of airflow. Practical implications The designed materials can be used for rapid prototyping of medical devices. Originality/value The new materials have been immediately used in the construction of an emergency lung ventilator, Q-vent, which has been used in different countries during the COVID-19 crisis.

434 Precision Oral Appliance Therapy: The Prime-Time Treatment for OSA

Abstract Introduction CPAP was previously considered the “gold standard” due to its high efficacy in eliminating obstructive events. Despite improvements in technology, the “effectiveness” of CPAP has been compromised by poor real-world compliance. Technological improvements have improved the “effectiveness” of Oral Appliances. This study reports the efficacy of a novel, precision engineered Oral Appliance for the primary treatment of all severities of OSA. Methods Digital scans and digital bite registrations were recorded with a George Gauge utilizing a a 3mm bite fork. Initial protrusion was set at 40–60% and varied according to the degree of overbite and overjet, the severity of OSA, and the presence or absence of TMJ symptoms. All patients were fitted with a ProSomnus (IA) MAD and titrated according to their subjective symptoms. An efficacy study was obtained with a HST after titration and compared to the initial PSG or HST. Results Outcome data on 85 patients (37 female, 48 males, aged 56.7 +/1 10.2 years) was retrospectively reviewed. The patients were consecutively ordered for follow up data, many patients did not return for follow ups. The pre-treatment AHI was 24.5 +/- 19.1 with 36 patients Mild, 26 Moderate and 23 Severe patients. O2 Nadir was 84.1% +/- 5.5%. Post treatment AHI was 5.5 +/- 4.9 with an AHI reduction of 71.6% +/- 20.3%. 59% of the patients scored &amp;lt;5, 31% 10 on the outcome AHI data. O2 Nadir improved to 88.2% overall. 31 patients had RERA’s (RDI-AHI) &amp;gt;10 with an average of 16.7 +/- 7.5, of these patients 27 saw a reduction of RERA’s of 54.4% from 16.9 to 7.1. Conclusion The data shows that a precision oral appliance is capable of successfully treating patients with all levels of severity, with the majority of patients treated to an AHI&amp;lt;5. 23 severe patients with an average AHI of 49.7 were treated to a final average of 8.6, 4 of the patients scored above 10. Additionally, patients successfully saw a reduction in upper airway resistance airflow as evidenced by a reduction of RERA’s of 54.5%, showing that a precision oral appliance can have a significant impact on the upper airway. Support (if any) None

Paediatrics: how to manage obstructive sleep apnoea syndrome.

Obstructive sleep apnoea syndrome (OSAS) is defined as the intermittent reduction or cessation of airflow due to partial or complete obstruction of the upper airway during sleep. Paediatric OSAS has specific contributing factors, presenting symptoms and management strategies in various age groups. Untreated OSAS can lead to detrimental effects on neurocognitive development and cardiovascular and metabolic functions of a growing child. In the past decade, practice guidelines have been developed to guide the evaluation and management of OSAS. This article provides a narrative review on the current diagnostic and treatment options for paediatric OSAS. Alternative diagnostic tools other than the standard polysomnography are discussed. Adenotonsillectomy is considered the first-line therapy yet it is not suitable for treatment of all OSAS cases. Nocturnal non-invasive positive airway pressure ventilation is effective and could be the priority treatment for patients with complex comorbidities, residual OSAS post-adenotonsillectomy or obesity. However, intolerance and non-adherence are major challenges of positive airway pressure therapy especially in young children. There is increasing evidence for watchful waiting and other gentler alternative treatment options in mild OSAS. The role of anti-inflammatory drugs as the primary or adjunctive treatment is discussed. Other treatment options, including weight reduction, orthodontic procedures and myofunctional therapy, are indicated for selected patients. Nevertheless, the successful management of paediatric OSAS often requires a multidisciplinary team approach.

Evaluation and Management of Adults with Obstructive Sleep Apnea Syndrome.

Obstructive sleep apnea syndrome (OSAS) is a common and underdiagnosed medical condition characterized by recurrent sleep-dependent pauses and reductions in airflow. While a narrow, collapsible oropharynx plays a central role in the pathophysiology of OSAS, there are other equally important nonanatomic factors including sleep-stage dependent muscle tone, arousal threshold, and loop gain that drive obstructive apneas and hypopneas. Through mechanisms of intermittent hypoxemia, arousal-related sleep fragmentation, and intrathoracic pressure changes, OSAS impacts multiple organ systems. Risk factors for OSAS include obesity, male sex, age, specific craniofacial features, and ethnicity. The prevalence of OSAS is rising due to increasing obesity rates and improved sensitivity in the tools used for diagnosis. Validated questionnaires have an important but limited role in the identification of patients that would benefit from formal testing for OSA. While an in-laboratory polysomnography remains the gold standard for diagnosis, the widespread availability and accuracy of home sleep apnea testing modalities increase access and ease of OSAS diagnosis for many patients. In adults, the most common treatment involves the application of positive airway pressure (PAP), but compliance continues to be a challenge. Alternative treatments including mandibular advancement device, hypoglossal nerve stimulator, positional therapies, and surgical options coupled with weight loss and exercise offer possibilities of an individualized personal approach to OSAS. Treatment of symptomatic patients with OSAS has been found to be beneficial with regard to sleep-related quality of life, sleepiness, and motor vehicle accidents. The benefit of treating asymptomatic OSA patients, particularly with regard to cardiovascular outcomes, is controversial and more data are needed.

Inferior meatus augmentation procedure (IMAP) normalizes nasal airflow patterns in empty nose syndrome patients via computational fluid dynamics (CFD) modeling.

Empty nose syndrome (ENS) is a controversial upper airway disorder most commonly associated with tissue loss from the inferior turbinates. The inferior meatus augmentation procedure (IMAP) has been shown to effectively reduce ENS symptoms in a durable manner, but the precise mechanisms that may govern this symptomatic improvement remain unknown. Five patients with ENS who underwent bilateral IMAP via submucosal costal cartilage implant were assessed. Pre-implant and 6 months post-implant computed tomography (CT) imaging for each ENS patient was analyzed in a blinded fashion using computational fluid dynamics (CFD) modeling to investigate intrapatient changes in airflow parameters. Following surgery, ENS patients have significantly improved symptoms as indexed by Empty Nose Syndrome 6-Item Questionnaire (ENS6Q) scoring (pre-implant: 14.00 ± 4.06 [mean ± standard deviation]; 95% confidence interval [CI], 10.44 to 17.56; post-implant: 4.8 ± 2.77; 95% CI, 2.37 to 7.23; Cohen's d = 2.64; p = 0.02). Using CFD, a significant shift in nasal airflow patterns was observed, where airflow deviates away from the middle meatus upon hitting the implant (pre-implant: 67.13% ± 11.14%; 95% CI, 60.22% to 74.04%; post-implant: 46.18% ± 12.81%; 95% CI, 38.23% to 54.12%; d = 1.74; p < 0.05) toward the inferior meatus (pre-implant: 30.55% ± 11.29%; 95% CI, 23.55% to 37.55%; post-implant: 42.59% ± 9.60%; 95% CI, 36.63 to 48.54%; d = 1.14; p < 0.05). No significant changes were found in nasal resistance (pre-implant: 0.102 ± 0.015; 95% CI, 0.092 to 0.112 Pa*s/mL; post-implant: 0.105 ± 0.041; 95% CI, 0.081 to 0.130 Pa*s/mL). In addition, the improvement of ENS6Q scoring significantly correlated with percent reduction in aberrant airflow through the middle meatus (R2 = 0.60, p = 0.04). This study supports our prior working hypothesis that disordered vectors of nasal airflow congregate in the middle meatus contribute to ENS symptoms, not nasal resistance. Moreover, these data illuminate a paradoxical, but consistent, restoration of nasal airflow to the inferior meatus following the replacement of turbinate tissue volume in the inferior meatus via IMAP surgery, potentially due to the Coandă effect.

Impact of aquatic sports on the evolution of obstructive sleep apnea and snoring and other breathing disorders

Obstructive sleep apnea (OSA) is a clinical syndrome characterized by periodic reduction (hypopnea) or cessation (apnea) of airflow through the nose/mouth during sleep due to collapse of the upper respiratory tract lasting 10 seconds or more. Severe snoring, hypoxemia and micro-awakenings occur, leading to sleep fragmentation, daytime fatigue and drowsiness. One of the key factors for the development of OSA is obesity. Excessive alcohol consumption, smoking, and presence of relatives with sleep apnea are risk-increasing factors. The gold standard in diagnosis is polysomnographic examination.Various values and indices are monitored, the most important of which is the apnea/hypopnea index. Treatment includes control of risk factors and removal of breathing obstacles. In patients with more severe obstructive sleep apnea syndrome, the gold standard of treatment remains constant positive pressure ventilation during sleep. Water sports have been part of programs for prevention of breathing disorders during sleep for many years. Our goal is to confirm whether after active sea treatment, water sports and weight loss of patients symptoms of obstructive sleep apnea and snoring would be favorably affected, as well as to actively promote and educate our patients about a more active sports (and aquatic) life. Results from our studies on patients with problems with the upper respiratory tract and OSA show that more than half did not practice sport. Some have common diseases, incl. allergic conditions. The influence of bad habits and the hereditary factor were confirmed as well. Obstructive sleep apnea and snoring syndrome is a serious disease with consequences for patients and other people. Screening of at-risk patients should be continued and studies should be conducted on the effectiveness of current and new methods for diagnosing and treating the syndrome.

Selective serotonin reuptake inhibitor use is associated with worse sleep-related breathing disturbances in individuals with depressive disorders and sleep complaints: a retrospective study.

The effects of serotonergic agents on respiration neuromodulation may vary according to differences in the serotonin system, such as those linked to depression. This study investigated how sleep-related respiratory disturbances relate to depression and the use of medications commonly prescribed for depression. Retrospective polysomnography was collated for all 363 individuals who met selection criteria out of 2,528 consecutive individuals referred to a specialized sleep clinic (Ottawa, Canada) between 2006 and 2016. The apnea-hypopnea index (AHI), oxygen saturation nadir, and oxygen desaturation index during REM and NREM sleep were analyzed using mixed analyses of covariance comparing 3 main groups: (1) medicated individuals with depressive disorders (antidepressant group; subdivided into the selective serotonin reuptake inhibitor and norepinephrine-dopamine reuptake inhibitor subgroups), (2) non-medicated individuals with depressive disorders (non-medicated group), and (3) mentally healthy control patients (control group). Individuals with depressive disorders (on antidepressants or not) had significantly higher AHIs compared to control patients (both P ≤ .007). The antidepressant group had a lower NREM sleep oxygen saturation nadir and a higher NREM sleep oxygen desaturation index than the control and non-medicated groups (all P ≤ .009). Within individuals with depressive disorders, independent of depression severity, the selective serotonin reuptake inhibitor group had a lower oxygen saturation nadir and a higher oxygen desaturation index during NREM sleep than the norepinephrine-dopamine reuptake inhibitor (both P ≤ .045) and non-medicated groups (both P < .001) and a higher NREM sleep AHI than the non-medicated group (P = .014). These findings suggest that the use of selective serotonin reuptake inhibitors may be associated with impaired breathing and worse nocturnal oxygen saturation in individuals with depressive disorders and sleep complaints, but this needs to be confirmed by prospective studies.

Non-intrusive reduced order model of urban airflow with dynamic boundary conditions

To address the problem that urban wind field simulations are limited by high computational requirements, a supervised machine learning framework for the non-intrusive model order reduction of urban airflow is proposed to provide fast predictions with dynamic boundary conditions. An integrated atmospheric modeling system is established by coupling the Parallelized LES Model (PALM) with the Urban Canopy Model (UCM) which embedded in the Weather Research and Forecasting (WRF) model to simulate the high-resolution urban wind field. Within this machine learning framework, encoders and decoders are trained to compress and reproduce the full-order airflow data. The eXtreme Gradient Boost regression models (XGBoost) are trained to map the boundary conditions to the latent vectors in the encoders and decoders. Thus, high resolution urban airflow can be predicted rapidly by the XGBoost-decoder models with the input of boundary conditions. By comparing four types of encoding-decoding models (i.e., the proper orthogonal decomposition models, autoencoders with linear/nonlinear fully connected neural networks and autoencoders with Convolutional Neural Network (AE-CNN)), we find that the AE-CNN model with advantages of portable model size and convenient updating procedure is capable for high resolution simulations of urban airflow with dynamic boundary conditions at a low computational cost.

Impact of Filtration Conditions on Air Quality in an Operating Room

The aim of this study was to assess the impact of ventilation and filtration conditions on particle concentrations in an orthopedic operating room. Total particle, viable particle, and CO2 concentration were measured under three different situations, namely before air filter replacement, after air filter replacement, and in an operating room with a new air conditioning system. Before air filter replacement, the mean values of airflow, total particle concentration, and viable particle concentration were 706 m3/h, 15.0 × 106 ± 4.0 × 106 particles/m3, and 57 CFU/m3, respectively. After replacement, the airflow increased to 1954 m3/h, and total and viable particle concentrations decreased to 0.4 × 106 ± 0.2 × 106 particles/m3 and 24 CFU/m3, respectively. In the room with a new air conditioning system, the airflow was 2051 m3/h, and total and viable particle concentrations were 0.3 × 106. ± 0.1 × 106 particles/m3 and 15 CFU/m3, respectively. The CO2 levels were 663 ppm (before), 659 ppm (after), and 574 ppm (new room). The results showed that inappropriate or no maintenance of filters in an air conditioning system had significant negative effects on indoor air quality in operating rooms. Air conditioning systems operating with saturated filters can be affected by pressure drop, which can lead to a reduction in airflow, thereby resulting in an increase in the average total particle and viable particle concentrations and the risk of infection in operating rooms. However, the results showed that the CO2 concentration was not affected by the filter replacement.

16S Metagenomics Reveals Dysbiosis of Nasal Core Microbiota in Children With Chronic Nasal Inflammation: Role of Adenoid Hypertrophy and Allergic Rhinitis.

Allergic rhinitis (AR) and adenoid hypertrophy (AH) are, in children, the main cause of partial or complete upper airway obstruction and reduction in airflow. However, limited data exist about the impact of the increased resistance to airflow, on the nasal microbial composition of children with AR end AH. Allergic rhinitis (AR) as well as adenoid hypertrophy (AH), represent extremely common pathologies in this population. Their known inflammatory obstruction is amplified when both pathologies coexist. In our study, the microbiota of anterior nares of 75 pediatric subjects with AR, AH or both conditions, was explored by 16S rRNA-based metagenomic approach. Our data show for the first time, that in children, the inflammatory state is associated to similar changes in the microbiota composition of AR and AH subjects respect to the healthy condition. Together with such alterations, we observed a reduced variability in the between-subject biodiversity on the other hand, these same alterations resulted amplified by the nasal obstruction that could constitute a secondary risk factor for dysbiosis. Significant differences in the relative abundance of specific microbial groups were found between diseased phenotypes and the controls. Most of these taxa belonged to a stable and quantitatively dominating component of the nasal microbiota and showed marked potentials in discriminating the controls from diseased subjects. A pauperization of the nasal microbial network was observed in diseased status in respect to the number of involved taxa and connectivity. Finally, while stable co-occurrence relationships were observed within both control- and diseases-associated microbial groups, only negative correlations were present between them, suggesting that microbial subgroups potentially act as maintainer of the eubiosis state in the nasal ecosystem. In the nasal ecosystem, inflammation-associated shifts seem to impact the more intimate component of the microbiota rather than representing the mere loss of microbial diversity. The discriminatory potential showed by differentially abundant taxa provide a starting point for future research with the potential to improve patient outcomes. Overall, our results underline the association of AH and AR with the impairment of the microbial interplay leading to unbalanced ecosystems.

Investigation the Integration of Heliostat Solar Receiver to Gas and Combined Cycles by Energy, Exergy, and Economic Point of Views

Due to the high amount of natural gas resources in Iran, the gas cycle as one of the main important power production system is used to produce electricity. The gas cycle has some disadvantages such as power consumption of air compressors, which is a major part of gas turbine electrical production and a considerable reduction in electrical power production by increasing the environment temperature due to a reduction in air density and constant volumetric airflow through a gas cycle. To overcome these weaknesses, several methods are applied such as cooling the inlet air of the system by different methods and integration heat recovery steam generator (HRSG) with the gas cycle. In this paper, using a heliostat solar receiver (HSR) in gas and combined cycles are investigated by energy, exergy, and economic analyses in Tehran city. The heliostat solar receiver is used to heat the pressurized exhaust air from the air compressor in gas and combined cycles. The key parameter of the three mentioned analyses was calculated and compared by writing computer code in MATLAB software. Results showed the use of HSR in gas and combined cycles increase the annual average energy efficiency from 28.4% and 48.5% to 44% and 76.5%, respectively. Additionally, for exergy efficiency, these increases are from 29.2% and 49.8% to 45.2% and 78.5%, respectively. However, from an economic point of view, adding the HRSG increases the payback period (PP) and it decreases the net present value (NPV) and internal rate of return (IRR).

Behavioral responses of Diaphorina citri to host plant volatiles in multiple-choice olfactometers are affected in interpretable ways by effects of background colors and airflows.

In several phytophagous hemipterans, behavior appears to be mediated by both visual and chemical cues. For the Asian citrus psyllid (ACP) Diaphorina citri (Hemiptera: Liviidae), olfactometric assays are generally difficult to interpret owing to the low proportion of individuals responding to odors (~30–40%), which compromises the efficiency and reliability of the results of behavioral tests. In the present study, the ACP behavioral response to emitted odors from sweet orange (Citrus sinensis L. Osbeck) flushes in a 4-arm olfactometer using different colors (four white-, two white- and two yellow- on opposite sides, or four yellow-colored fields), and the role of the airflow in the concentration of volatile organic compounds (VOCs) were assessed at two airflows [0.4 and 0.1 L/min (LPM)]. Exposure to ‘Pera’ sweet orange or clean air in treatments with four yellow-colored-fields increased the response rate of ACP females to the odor sources compared with exposure to ‘Pera’ sweet orange or clean air in treatments with four white-colored-fields, independently of the odor source and airflow tested. For the assays using two white- and two yellow-colored fields on opposite sides and 0.4 or 0.1 LPM airflow, the residence time of ACP females to odors (‘Pera’ sweet orange or clean air) was similar or higher in treatments using yellow- than those using white-colored fields. For both assays (VOCs and olfactometric behavioral parameters), the reduction in airflow from 0.4 to 0.1 LPM greatly changed the airborne concentration and ACP behavior. Quantitative chemical analyses revelead that the concentration of most compounds emitted by ‘Pera’ sweet orange flushes for the headspace using 0.1 LPM airflow were greater than the concentrations measured using 0.4 LPM airflow. Therefore, this treatment design provides an useful tool to assess the ACP behavioral response to the odors from citrus plants, and it can also help in the discrimination of dose-response screenings for VOCs or conspecific insects.

0555 The Relationship Between Sleep Efficiency and Apnoea Hypopnoea Index (AHI) in Adult Obese Males

Abstract Introduction Prevalence of obesity is increasing worldwide. According to OECD 2017, the prevalence of obesity is 19.5% worldwide. Obesity leads to disturbed sleep due to complete or partial obstruction of upper airways i.e. obstructive sleep apnoea. This disturbed sleep leads to increased sympathetic discharge &amp; further obesity and thus forms a vicious cycle of obesity disturbing sleep and sleep disturbance increasing obesity. The purpose of the present study was to correlate the sleep efficiency with apnoea hypopnea index (AHI) in adult obese males. Methods Nineteen adult obese males (26 years- 60 years), non-smokers were recruited for this cross-sectional study. The obesity criteria was taken as BMI ≥ 25 kg/m2. They underwent an overnight polysomnographic examination with total 68 channels and 32 EEG inputs. The episodes of apnea were defined as complete cessation of airflow for ≥10 s, and hypopnea consisted of a ≥30% reduction in oronasal airflow accompanied by a reduction in oxygen saturation measured by pulse oximetry of at least 4%. AHI was determined by the frequency of these events per hour during sleep time based on the results of the overnight polysomnography. Sleep efficiency index was calculated by dividing total duration of sleep stages (N1+ N2+ N3+ REM) by total time in bed. Results We tested for normality through Shapiro Wilk test and our data was found to be non-parametric. Hence Spearman correlation between sleep efficiency and AHI was performed. The correlation was non- significant with p value 0.1245 and r = - 0.365. The correlation of BMI with sleep efficiency was significant (p= 0.0195) with r value= -0.5303. Conclusion The results conclude that the sleep efficiency worsens with obesity. Although the correlation between AHI and sleep efficiency was not found significant, a negative r value indicates that the sleep efficiency decreases with increased obstructive events during sleep. Support All India Institute of Medical Sciences Jodhpur

PATIENTS PROFILE AT THE SLEEP APNEA OUTPATIENT CLINIC AT A UNIVERSITY HOSPITAL

Introduction: Obstructive sleep apnea syndrome (OSAS) is characterized by recurrent collapses of the pharyngeal region during sleep, resulting in a substantial reduction in airflow (apnea and hypopnea), despite respiratory efforts. Objective: To report the profile of patients referred to the Sleep Apnea Outpatient Clinic of Hospital Universitário Onofre Lopes (HUOL), emphasizing on the main risk factors associated with OSAS. Methodology: It is retrospective study, cross-sectional, in which data obtained by reviewing medical records of patients seen at the sleep apnea outpatient clinic between 2017 and 2019 were used. Results: Medical records of 43 patients were evaluated, being (62, 8%) male and (37.2%) female. All patients underwent previous screening before polysomnography, being divided into three groups: Group I - with mild OSAS: 8 patients (18.6%); Group II - with moderate OSAS: 18 patients (41.8%); Group III - with severe OSAS: 17 patients (39.5%). Conclusion: Sleep apnea syndrome is commonly correlated with metabolic syndrome.

Expiratory airflow obstruction due to tracheostomy tube: A spirometric study in 50 patients

Tracheostomy is commonly used in intensive care units and in head and neck departments. Airway obstruction due to occluded cuffless tracheostomy tubes themselves remains unknown, although capping trials are commonly used before decannulation. The aim of this study was to evaluate the extent to which airway obstruction can be caused by occluded cuffless tubes in patients who underwent head and neck surgery. Prospective Research Outcome. University teaching hospital. Fifty patients requiring transient tracheostomy after head and neck surgery. A flow-volume loop (FVL) through the mouth using a portable spirometer, with the occluded fenestrated cuffless tube, was measured before and immediately after decannulation, by obstructing the orifice of tracheostomy tube. The measurement of FVL recorded the forced vital capacity (FVC), forced expiratory volume in 1second (FEV1 ), peak expiratory flow (PEF), forced expiratory flow at 50% of FVC, peak inspiratory flow (PIF) and forced inspiratory flow at 50% of FVC. A statistically significant difference between all spirometric parameters was found. Mean PEF and PIF, respectively, increased from 2.8 to 4.5L/s (P<.0001) and 2.3 to 2.7L/s (P<.01) before and after decannulation, with a strong positive correlation (r=0.7; P<.05). A mean expiratory (34%) and inspiratory (9%) airflow reduction was observed due to cannula. Occluded cuffless tracheostomy tubes cause a dramatic airflow obstruction, mainly in the expiratory phase of FVL. This should be taken into account during capping trials.

Surgical and Clinical Reactivation for Elective Procedures during the COVID-19 Era: A Global Perspective

Surgical and Clinical Reactivation for Elective Procedures during the COVID-19 Era: A Global Perspective