Negative Pressure Ventilation Research Articles

Numerical Simulation on Particulate Matter Emissions from a Layer House during Summer in Northeast China

Particulate matter (PM) emitted from livestock and poultry production contributes to atmospheric aerosol loading, affecting animal health and the surrounding atmospheric environment. However, developing and optimizing remediation technologies require a better understanding of air pollutant concentrations, the emission plumes, and the mechanism of emission. Previous studies have primarily focused on indoor air pollution research, while outdoor research is relatively rare. Field test research is not only costly but also consumes extensive amounts of time. The application of computational fluid dynamics (CFD) technology can save a lot of measurement time and repetitive labor, in order to better understand the diffusion fundamentals and spatial and temporal distribution differences of PM. This study monitored the PM concentrations of different particle sizes inside and outside a layer house with negative pressure ventilation in Northeast China during the summer of 2021. These data were also used to validate the three-dimensional simulation of the PM concentrations inside and outside of the layer house in various scenarios of wind directions at different times by CFD technology. Through correlation analysis, it is found that temperature was positively correlated with PM1 and PM2.5, and relative humidity and wind speed were negatively correlated with PM, which has a greater impact on PM10 and total suspended particulate (TSP). The particle size was proportional to the diffusion distance and diffusion height, time, and wind direction both have an impact on the spread of PM. Considering the environmental conditions in Northeast China, increasing the height of the fan by 1 m was suggested to reduce the diffusion of PM concentration. In addition, the diffusion patterns and transport paths in this study provide valuable information for improving control measures to minimize the influence of PM on both animal health and air quality.

Normothermic Negative Pressure Ventilation <em>Ex Situ</em> Lung Perfusion: Evaluation of Lung Function and Metabolism

Lung transplantation (LTx) remains the standard of care for end-stage lung disease. A shortage of suitable donor organs and concerns over donor organ quality exacerbated by excessive geographic transportation distance and stringent donor organ acceptance criteria pose limitations to current LTx efforts. Ex situ lung perfusion (ESLP) is an innovative technology that has shown promise in attenuating these limitations. The physiologic ventilation and perfusion of the lungs outside of the inflammatory milieu of the donor body affords ESLP several advantages over traditional cold static preservation (CSP). There is evidence that negative pressure ventilation (NPV) ESLP is superior to positive pressure ventilation (PPV) ESLP, with PPV inducing more significant ventilator-induced lung injury, pro-inflammatory cytokine production, pulmonary edema, and bullae formation. The NPV advantage is perhaps due to the homogenous distribution of intrathoracic pressure across the entire lung surface. The clinical safety and feasibility of a custom NPV-ESLP device have been demonstrated in a recent clinical trial involving extender criteria donor (ECD) human lungs. Herein, the use of this custom device is described in a juvenile porcine model of normothermic NPV-ESLP over a 12 h duration, paying particular attention to management techniques. Pre-surgical preparation, including ESLP software initialization, priming, and de-airing of the ESLP circuit, and the addition of anti-thrombotic, anti-microbial, and anti-inflammatory agents, is specified. The intraoperative techniques of central line insertion, lung biopsy, exsanguination, blood collection, cardiectomy, and pneumonectomy are described. Furthermore, particular focus is paid to anesthetic considerations, with anesthesia induction, maintenance, and dynamic modifications outlined. The protocol also specifies the custom device's initialization, maintenance, and termination of perfusion and ventilation. Dynamic organ management techniques, including alterations in ventilation and metabolic parameters to optimize organ function, are thoroughly described. Finally, the physiological and metabolic assessment of lung function is characterized and depicted in the representative results.

Normothermic Negative Pressure Ventilation Ex Situ Lung Perfusion: Evaluation of Lung Function and Metabolism.

Lung transplantation (LTx) remains the standard of care for end-stage lung disease. A shortage of suitable donor organs and concerns over donor organ quality exacerbated by excessive geographic transportation distance and stringent donor organ acceptance criteria pose limitations to current LTx efforts. Ex situ lung perfusion (ESLP) is an innovative technology that has shown promise in attenuating these limitations. The physiologic ventilation and perfusion of the lungs outside of the inflammatory milieu of the donor body affords ESLP several advantages over traditional cold static preservation (CSP). There is evidence that negative pressure ventilation (NPV) ESLP is superior to positive pressure ventilation (PPV) ESLP, with PPV inducing more significant ventilator-induced lung injury, pro-inflammatory cytokine production, pulmonary edema, and bullae formation. The NPV advantage is perhaps due to the homogenous distribution of intrathoracic pressure across the entire lung surface. The clinical safety and feasibility of a custom NPV-ESLP device have been demonstrated in a recent clinical trial involving extender criteria donor (ECD) human lungs. Herein, the use of this custom device is described in a juvenile porcine model of normothermic NPV-ESLP over a 12 h duration, paying particular attention to management techniques. Pre-surgical preparation, including ESLP software initialization, priming, and de-airing of the ESLP circuit, and the addition of anti-thrombotic, anti-microbial, and anti-inflammatory agents, is specified. The intraoperative techniques of central line insertion, lung biopsy, exsanguination, blood collection, cardiectomy, and pneumonectomy are described. Furthermore, particular focus is paid to anesthetic considerations, with anesthesia induction, maintenance, and dynamic modifications outlined. The protocol also specifies the custom device's initialization, maintenance, and termination of perfusion and ventilation. Dynamic organ management techniques, including alterations in ventilation and metabolic parameters to optimize organ function, are thoroughly described. Finally, the physiological and metabolic assessment of lung function is characterized and depicted in the representative results.

Optimal technology innovation of teaching buildings for primary and middle schools based on compound negative pressure ventilation

Optimal technology innovation of teaching buildings for primary and middle schools based on compound negative pressure ventilation

The effect of air temperature, velocity and humidity on respiration rate and rectal temperature as an expression of heat stress in gestating sows.

Global warming combined with increased production (i.e. more piglets, more milk and consequently more heat) means that sows are more often challenged by heat stress. The objective was to develop an effective temperature (ET) equation to predict how air temperature, velocity and humidity affect the respiration rate (RR), rectal temperature (RT) and skin temperature (ST) as an expression of heat stress in gestating sows in order to elucidate the relationship between the thermal parameters and the sows' perception of the environment. The experimental room was equipped with a negative pressure ventilation system with diffuse air inlet through the ceiling, electrical heaters, steam generators and dehumidifiers. An air distribution unit was constructed to generate vertical air velocity. A total of 16 gestating sows were exposed to three temperatures (25°C, 29°C and 33°C), two levels of relative humidity (30% and 70%) and three levels of air velocity (0.2ms-1, 1ms-1 and 2.5ms-1). The RR, RT and ST were recorded every 30min throughout the three 2-h test periods. The estimated effects of humidity and velocity in relation to effect of temperature was nearly independent of whether it was determined from RR or RT, whereas the effect of humidity was much smaller when determined from ST. High coefficients of determination (>0.97) were found for the second order relationship between the estimated ET and RR, RT and ST. An increase in relative humidity from 50 to 70% corresponded to an increase in ET of 0.9°C, while an increase in air velocity from 0.2 to 1.0ms-1 corresponded to a decrease in ET of 1.2°C. The applied ET equation was useful for expressing the combined effect of temperature, humidity and velocity on animals exposed to heat stress. However, multiplying the effect of velocity by the temperature gradient between the animal and the surrounding air did not improve the estimation.

Impact of the COVID-19 pandemic on catheterization laboratory procedural volumes at a tertiary cardiac centre in a low- & middle-income country in South Asia

BackgroundGlobally, reports have suggested that cardiac catheterization procedures, particularly elective coronary procedures declined as a result of the COVID-19 pandemic. However, there is scarce data on this aspect, in terms of a South Asian low- & middle-income country (LMIC) setting.PurposeWe aimed to evaluate temporal trends and impact of the pandemic on elective and emergency cardiac catheterization procedural volumes at a high-volume tertiary cardiac centre in a LMIC.MethodsData on both emergency and elective catheterization procedures, including coronary angiography, percutaneous coronary intervention (PCI), peripheral angiography, pacing & electrophysiology (EP) were collected from January to December 2020, and compared with corresponding data for the same months in 2019. Data were obtained from hospital's catheterization laboratory database. The difference was expressed as a percentage (%Δ). Data for each quarter were compared using paired t-test. A p value <0.05 was considered significant.ResultsOverall, a significant (32.4%) reduction of cath lab procedures was seen in 2020, as compared with 2019 (p=0.006). There were significantly reduced numbers of coronary angiographies (%Δ −31.4%; p=0.009), PCI (%Δ −32.2%; p=0.008), peripheral procedures (%Δ −69.9%; p=0.001) and pacing & EP procedures (Δ−-48.7%; p=0.001) in 2020, as compared with 2019 (Table 1 & Figure 1). For coronary procedures this was most marked in 2nd and 3rd quarters of 2020 (p<0.05). The greatest deficits for coronary angiographies were observed in April 2020, compared to 2019 (Δ −85.1%); the greatest reductions in PCI (Δ-87.7%) and pacing & EP (Δ −94.7%) were seen in May 2020, coinciding with the nation-wide lockdown measures. Coronary procedures showed a gradually increasing trend since July 2020. Given their elective nature, no peripheral procedures were performed from April to July 2020. In terms of PCI, there was a significant reduction in elective procedures in the 2nd quarter of 2020 (p=0.001), with a steep “catch-up” incline in September (Δ +2.9%) and October 2020 (Δ −8.3%), coinciding with availability of in-hospital COVID19 screening tests (Table 1). Among ad hoc PCI for acute coronary syndrome (ACS), although a 32.3% reduction was seen overall (p=0.108), a significant decrease was only observed in the 2nd quarter. Ad hoc PCI for non-ACS was significantly reduced throughout 2nd to 4th quarters of 2020. In line with national guidelines preferring fibrinolysis as first-line for STEMI, as well as absence of negative pressure ventilation cath labs and unavailability of rapid-screening COVID test kits, no primary PCI procedures were performed since May 2020.ConclusionThe impact of COVID-19 resulted in a significant reduction in all cardiac catheterization procedures in 2020, as compared with 2019. This reduction was most marked for coronary procedures in the 2nd and 3rd quarters of 2020, with a significant reduction in elective procedures.Funding AcknowledgementType of funding sources: None. Table 1

Neuromodulatory Support for Breathing and Cardiovascular Action During Development.

Neonatal survival requires precise control of breathing and cardiovascular action, with fatal consequences or severe injury without support. Prematurity presents multiple opportunities to disrupt cardiorespiratory regulation, leading to expressions of apnea of prematurity, periodic breathing, and inappropriate cardiovascular responses to apnea. Failed breathing control can result from altered breathing drives, typically arising from untimely development of sensory or motor coordination processes. Some drives, such as temperature, are a special concern in neonates with low body mass, enhancing susceptibility to rapid body cooling. Chemical drives, such as pH or CO2 or O2, may be inadequately developed; in some conditions, such as congenital central hypoventilation syndrome (CCHS), breathing responses to CO2 or low O2 may be reduced or absent, and coupling of cardiovascular responses to breathing changes are abolished. Sleep states exert profound influences on both chemical and temperature drives, with rapid eye movement (REM) sleep potentially modifying descending temperature influences, and state transitions significantly altering respiratory responses to chemical stimuli. In addition, neonates spend the majority of time in REM sleep, a state which induces a generalized inhibition of skeletal muscle activity that abolishes muscle tone to upper airway and thoracic wall muscles, enhancing the likelihood for obstructive sleep apnea. Although disrupted regulatory drives can often be replaced by positive (or negative) pressure ventilation, such as continuous positive airway pressure or enhanced by manipulating neurotransmitter action via caffeine, those approaches may exert negative consequences in the long term; the lungs of neonates, especially premature infants, are fragile, and easily injured by positive pressure. The consequences of caffeine use, acting directly on neural receptors, although seemingly innocuous in the near-term, may have long-term concerns and disrupts the integrity of sleep. The developmental breathing field needs improved means to support ventilation when one or more drives to respiration fail, and when the cardiovascular system, depending heavily on interactions with breathing, is compromised. Neuromodulatory procedures which manipulate the vestibular system to stabilize breathing or use tactile or proprioceptive stimuli to activate long-established reflexive mechanisms coupling limb movement with respiratory efforts can provide support for central and obstructive apnea, as well as for periodic breathing and cardiovascular action, particularly during sleep.

Application of Pandemic Intelligence in Dynamic Data in Taiwan.

Taiwan was successful in containing the spread of the novel coronavirus (COVID-19) in 2020. One major factor in this success was the compilation and provision of comprehensive information about the pandemic. The present study proposes a pandemic intelligence system that provides data on the number of epidemic prevention professionals in each county and city, as well as daily confirmed cases, the demographics of the confirmed cases, and available resources (negative-pressure room beds and artificial ventilation apparatuses) in hospitals. Furthermore, the system provides the location of pharmacies selling masks and their current inventories, as well as the distribution of crowds at popular tourist destinations and social-distance monitoring. The most frequently used map layer in the thematic map of the pandemic is that of crowd distribution during the study period from March 2020 until the end of the same year. The case study used in this investigation for applying the system is represented by the 4-day weekend for Tomb-Sweeping Day of 2020. Through the real-time analysis of dynamic data and the integration of intelligence, the system offers a clear insight into changes in relevant information and, thus, enables the preemptive deployment of control measures by the county/city governments regarding pandemic management.

Prevalence of Eimeria sp. in Broiler Poultry Houses with Positive and Negative Pressure Ventilation Systems in Southern Brazil.

Coccidiosis is an enteric disease caused by protozoa of the Eimeria genus and is of great economic relevance in industrial aviculture. The objective of this work was to determine the prevalence of Eimeria sp. in broiler poultry houses with positive (System 1) and negative (System 2) pressure ventilation and assess the associated factors. A transversal study was conducted using 8 random broiler chickens from 64 houses (n = 512) and macroscopic and histologic evaluation of the intestines, as well as PCR for Eimeria sp. The prevalence of Eimeria sp. was 90.6% (95% confidence interval [CI]: 97.8-83.5), with 93.8% (95% CI: 100-85.4) in System 1 and 87.5% (95% CI: 99.0-76.0) in System 2. The most prevalent species was Eimeria acervulina, and the most common combination was Eimeria acervulina, Eimeria maxima, and Eimeria tenella. System 2 and the negative Eimeria subgroup showed the best results for feed conversion and daily weight gain. By evaluating litter treatment, we found that quicklime reduced the risk of presence of Eimeria maxima and Eimeria tenella. In conclusion, Eimeria sp. had a high prevalence in both systems, with a predominance of mixed infections. System 2 and negative flocks showed the best zootechnical results.

Derivation and Validation of the Critical Bronchiolitis Score for the PICU.

To derive and internally validate a bronchiolitis-specific illness severity score (the Critical Bronchiolitis Score) that out-performs mortality-based illness severity scores (e.g., Pediatric Risk of Mortality) in measuring expected duration of respiratory support and PICU length of stay for critically ill children with bronchiolitis. Retrospective database study using the Virtual Pediatric Systems (VPS, LLC; Los Angeles, CA) database. One-hundred twenty-eight North-American PICUs. Fourteen-thousand four-hundred seven children less than 2 years old admitted to a contributing PICU with primary diagnosis of bronchiolitis and use of ICU-level respiratory support (defined as high-flow nasal cannula, noninvasive ventilation, invasive mechanical ventilation, or negative pressure ventilation) at 12 hours after PICU admission. Patient-level variables available at 12 hours from PICU admission, duration of ICU-level respiratory support, and PICU length of stay data were extracted for analysis. After randomly dividing the cohort into derivation and validation groups, patient-level variables that were significantly associated with the study outcomes were selected in a stepwise backward fashion for inclusion in the final score. Score performance in the validation cohort was assessed using root mean squared error and mean absolute error, and performance was compared with that of existing PICU illness severity scores. Twelve commonly available patient-level variables were included in the Critical Bronchiolitis Score. Outcomes calculated with the score were similar to actual outcomes in the validation cohort. The Critical Bronchiolitis Score demonstrated a statistically significantly stronger association with duration of ICU-level respiratory support and PICU length of stay than mortality-based scores as measured by root mean squared error and mean absolute error. The Critical Bronchiolitis Score performed better than PICU mortality-based scores in measuring expected duration of ICU-level respiratory support and ICU length of stay. This score may have utility to enrich interventional trials and adjust for illness severity in observational studies in this very common PICU condition.

RESULTS OF INSPECTION OF THE STATE OF PROVIDING THE MICROCLIMATE IN THE PIG FARM WITH A NEGATIVE PRESSURE VENTILATION SYSTEM

The most popular microclimate system today is based on a negative pressure ventilation system. Because it is easier to use and consumes less energy than any other forced ventilation system. The purpose of the research is to inspect the room for keeping piglets on rearing with a negative pressure ventilation system to identify shortcomings and deviations of the microclimate parameters necessary for further improvement. According to the results of the inspection of the rearing room for piglets, it was found that according to the existing system of negative pressure in the rearing room for piglets, most indicators (air velocity, ammonia, carbon dioxide, hydrogen sulfide, oxygen) are within normal limits. According to the results of the inspection of the room for keeping piglets for rearing with a negative pressure microclimate system, it was found that the air temperature in the room does not meet the recommended limits and reaches 30 °C, while the maximum recommended temperature for piglets for fattening is 20 °C. The air temperature is uneven along the length of the room, which is caused by uneven air supply from the vents. According to the results of the inspection of the room for piglets with a negative pressure microclimate system, it was found that the relative humidity at the height of the animals is higher than the recommended norms and reaches 95%, while the recommended humidity for piglets for fattening is not more than 80%. According to the results of the inspection of the room for keeping piglets for rearing with a negative pressure microclimate system, it can be stated that it is necessary to improve the air cooling system and replan the ventilation ducts of the ventilation system to ensure even air flow.

Effects of mechanical ventilation with expiratory negative airway pressure on porcine pulmonary and systemic circulation: mechano-physiology and potential application

We studied the impact of mechanically regulated, expiratory negative airway pressure (ENAP) ventilation on pulmonary and systemic circulation including its mechanisms and potential applications. Microminipigs weighing about 10 kg were anesthetized (n = 5). First, hemodynamic variables were evaluated without and with ENAP to approximately −16 cmH2O. ENAP significantly increased heart rate and cardiac output, but decreased right atrial, pulmonary arterial and pulmonary capillary wedge pressures. Second, the evaluation was repeated following pharmacological adrenergic blockade, modestly blunting ENAP effects. Third, fluvoxamine (10 mg/kg) was intravenously administered to intentionally induce cardiovascular collapse in the presence of adrenergic blockade. ENAP was started when systolic pressure was < 40 mmHg in the animals assigned to ENAP treatment-group. Fluvoxamine induced cardiovascular collapse within 4 out of 5 animals. ENAP increased systolic pressure to > 50 mmHg (n = 2): both animals fully recovered without neurological deficit, whereas without ENAP both animals died of cardiac arrest (n = 2). ENAP may become an innovative treatment for drug-induced cardiovascular collapse.

Low-frequency Intrapulmonary Percussive Ventilation Increases Aerosol Penetration in a 2-Compartment Physical Model of Fibrotic Lung Disease

In patients with fibrotic pulmonary disease such as idiopathic pulmonary fibrosis (IPF), inhaled aerosols deposit mostly in the les affected region of the lung, resulting in suboptimal pharmacokinetics of airway-delivered treatments. Refinement of aerosol delivery technique requires new models to simulate the major alterations of lung physiology associated with IPF, i.e. heterogeneously reduced lung compliance and increased airway caliber. A novel physical model of the respiratory system was constructed to simulate aerosol drug delivery in spontaneously breathing (negative pressure ventilation) IPF patients. The model comprises upper (Alberta idealized throat) and lower airway (plastic tubing) models and branches into two compartments (Michigan lung model) which differ in compliance and caliber of conducting airway. Aerosol penetration and deposition (using NaF as a model aerosol) in the model was studied in different conditions. The model was able to reproduce the heterogeneous, compliance-dependent reduction in ventilation and aerosol penetration seen in the fibrotic lung regions in IPF. Addition of intrapulmonary percussive ventilation (IPV) induces a 2-3 fold increase in aerosol penetration in the low-complaince/high airway caliber compartment of the model, demonstrating the responsiveness of the model to therapeutic intervention. Thanks to the model, we observed that reduced compliance of target lung regions is a critical determinant of aerosol penetration, and thus presumably of aerosol deposition. This finding underscores the need for techniques specifically tailored to enhance delivery of inhaled aerosols to low compliance regions of lungs. Low-frequency IPV (≤ 3 Hz) pulses may represent an attractive option to increase aerosol deposition in fibrotic lung regions.

Randomized Controlled Trial of Negative Pressure Ventilation: We First Need a National Patient Registry.

Division of Pediatric Critical Care Medicine, Department of Pediatrics, Duke University Medical Center, Durham, NC. Dr. Rotta received funding from Breas US, Vapotherm, and Elsevier. For information regarding this article, E-mail: [email protected]

Randomized Controlled Trial of Negative Pressure Ventilation: We First Need Characterized Physiology

1 Department of Pediatrics, Division of Pediatric Critical Care Medicine, Beatrix Children’s Hospital, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. 2 Critical care, Anesthesiology, Peri-operative & Emergency medicine (CAPE), University of Groningen, Groningen, The Netherlands. Dr. Kneyber received funding from Vyaire. For information regarding this article, E-mail: [email protected]

Multi-omics reveals age-related differences in the diaphragm response to mechanical ventilation: a pilot study

BackgroundOld age is associated with a significantly increased mortality in COVID-19 patients exposed to long-term controlled mechanical ventilation (CMV) and suggested to be due to the hyperinflammatory response associated with the viral infection. However, our understanding of age-related differences in the response to CMV in the absence of a viral infection remains insufficient.MethodsYoung (7–8 months) and old (28–32 months) F344 BN hybrid rats were exposed to the ICU condition for 5 days, i.e., complete immobilization, mechanical ventilation, and extensive monitoring. Transcriptomic (RNA-Seq) and proteomics (Proximity Extension Assay) analyses of the diaphragm and proteomics analysis of plasma were conducted to investigate the molecular differences between young and old rats exposed to the ICU condition.ResultsAccording to multi-omics analyses, significant differences were observed in the diaphragm between young and old rats in response to 5 days CMV and immobilization. In young rats, metabolic pathways were primarily downregulated in response to immobilization (post-synaptic blockade of neuromuscular transmission). In old rats, on the other hand, dramatic immune and inflammatory responses were observed, i.e., an upregulation of specific related pathways such as “IL-17 signaling pathway”, along with a higher level of inflammatory factors and cytokine/chemokine in plasma.ConclusionsThe dramatically increased mortality in old ICU patients with COVID-19-associated hyperinflammation and cytokine storm need not only reflect the viral infection but may also be associated with the ventilator induced diaphragm dysfunction (VIDD) and hyperinflammatory responses induced by long-term CMV per se. Although mechanical ventilation is a life-saving intervention in COVID-19 ICU patients, CMV should be cautiously used especially in old age and other means of respiratory support may be considered, such as negative pressure ventilation.

Facing Disaster During a COVID-19 Outbreak: What Emergency Medicine Experts Should Know?

Context: Since December 2019, the new coronavirus (COVID-19) has been identified as one of the significant challenges in the health systems of countries. Recently, the development and equipping of hospitals and medical centers have been considered as a priority, providing a variety of advanced services in the areas of diagnostic, therapeutic, and supportive services to patients. The present review aimed to shed light on the importance and crucial role of knowledge in the field of emergency medicine during the COVID-19 pandemic and to compare the local and international guidelines. Finally, in addition to the workplace and emergency practitioners’ acts, alongside the especial need to frequently disinfect with appropriate antiseptic materials, negative pressure ventilation should also be in the triage and emergency rooms. Besides, personal protection requirements should be sufficiently accessible, and emergency physicians should be trained to use them properly while adhering to safety principles. It is also recommended to use a cap, gown, appropriate mask, shield, and gloves during treatment, diagnostic and supportive measures, and practice frequent hand washing with antiseptic materials like alcohol solutions, as it reduces the risk of infection transmission. Moreover, it is imperative that nurses and physicians working in emergencies follow all safety principles at the end of the shift before entering their homes. Conclusions: Ultimately, the final goal is to reduce the virus transmission through early detection, supportive, diagnostic, and therapeutic actions, and appropriate follow-up.

“The role of a negative pressure ventilator coupled with oxygen helmet against COVID-19: a review”

BackgroundThe coronavirus (SARS-COV-2) pandemic has provoked the global healthcare industry by potentially affecting more than 20 14 million people across the globe, causing lasting damage to the lungs, notably pneumonia, ARDS (acute respiratory distress 15 syndrome), and sepsis with the rapid spread of infection. To aid the functioning of the lungs and to maintain the blood oxygen 16 saturation (SpO2) in coronavirus patients, ventilator assistance is required.Materials and methodsThe main purpose of this article is to outline the need 17 for the introduction of a non-invasive negative pressure ventilator (NINPV) as a promising alternative to positive pressure 18 ventilator (PPV) by elucidating the cons of non-invasive ventilators in clinical conditions like ARDS. Another motive is to 19 profoundly diminish the rate of infection spread by the employment of oxygen helmets, instead of endotracheal intubation in 20 invasive positive pressure ventilator (IPPV) or non-invasive positive pressure ventilator (NIPPV) like face masks and high-flow 21 nasal cannula (HFNC).Result and conclusionThe integration of oxygen helmet with NPV would result in a number of notable facets including the 22 degree of comfort delivered to patients who are exposed to various ventilator-induced lung injuries (VILI) in the forms of 23 atelectasis, barotrauma, etc. Likewise, preventing the aerosol-generating procedures (AGP) diminishes the rate of nosocomial 24 infections and providing a better environment to both the patients and the healthcare professionals.

Daytime alternatives for non-invasive mechanical ventilation in neuromuscular disorders.

Mechanical ventilation in recent years has benefited from the development of new techniques and interfaces. These developments allowed clinicians to offer increasingly personalised therapies with the combination of different complementary techniques for treating respiratory insufficiency in patients with neuromuscular diseases. The mouthpiece ventilation, intermittent abdominal pressure ventilator and the negative pressure ventilation can offer many patients alternative therapy options when ventilation is required for many hours a day. In this non-systematic review, we will highlight the use of alternative methods to non-invasive mechanical ventilation at positive pressure in neuromuscular patients, to ensure the optimal interface for each patient.

A pilot study of short-term hemodynamic effects of negative pressure ventilation in chronic obstructive pulmonary disease assessed using electrical cardiometry.

BackgroundPulmonary rehabilitation combined with negative pressure ventilation (NPV) demonstrated benefits in patients with chronic obstructive pulmonary disease (COPD). The effect of NPV remains unknown. This study aims to clarify the short‐term response of the hemodynamic outcome of NPV in patients with COPD undergoing pulmonary rehabilitation program by electrical cardiometry.MethodsThis is an observational retrospective study of COPD patients who had been treated in a pulmonary rehabilitation unit with NPV between January 2018 and December 2019 that were enrolled to analyze the hemodynamic outcomes.ResultsThirty patients with COPD that were undergoing a pulmonary rehabilitation program and were regularly receiving NPV were enrolled. Cardiac output (p < .001) and heart rate (p < .001) showed a significant decrease after NPV. Stroke volume did not demonstrate significant change (p = .15). There was a significant decrease in thoracic fluid content (p = .016) and a significant increase in stroke volume variation (p = .038) systemic vascular resistance (p < .001) and left ventricular ejection time (p < .001). Other hemodynamic parameters were all comparable before and after NPV.ConclusionsNegative pressure ventilation demonstrated an impact on hemodynamics in patients with chronic obstructive pulmonary disease undergoing pulmonary rehabilitation. Electrical cardiometry is a feasible method of determining the hemodynamic effects of negative pressure ventilation. Thoracic fluid content significantly decreased immediately after the NPV.