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Respiratory diseases are among the leading causes of death globally, with the COVID-19 pandemic serving as a prominent example. Issues such as infections affect a large population and, depending on the mode of transmission, can rapidly spread worldwide, impacting thousands of individuals. These diseases manifest in mild and severe forms, with severely affected patients requiring ventilatory support. The air-oxygen blender is a critical component of mechanical ventilators, responsible for mixing air and oxygen in precise proportions to ensure a constant supply. The most commonly used version of this equipment is the analog model, which faces several challenges. These include a lack of precision in adjustments and the inspiratory fraction of oxygen, as well as gas wastage from cylinders as pressure decreases. The research proposes a blender model utilizing only dynamic pressure sensors to calculate oxygen saturation, based on Bernoulli's equation. The model underwent validation through simulation, revealing a linear relationship between pressures and oxygen saturation up to a mixture outlet pressure of 500 cmH2O. Beyond this value, the relationship begins to exhibit non-linearities. However, these non-linearities can be mitigated through a calibration algorithm that adjusts the mathematical model. This research represents a relevant advancement in the field, addressing the scarcity of work focused on this essential equipment crucial for saving lives.

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OBJECTIVES: Ventilator dyssynchrony may be associated with increased delivered tidal volumes (V t s) and dynamic transpulmonary pressure (ΔP L,dyn ), surrogate markers of lung stress and strain, despite low V t ventilation. However, it is unknown which types of ventilator dyssynchrony are most likely to increase these metrics or if specific ventilation or sedation strategies can mitigate this potential. DESIGN: A prospective cohort analysis to delineate the association between ten types of breaths and delivered V t , ΔP L,dyn , and transpulmonary mechanical energy. SETTING: Patients admitted to the medical ICU. PATIENTS: Over 580,000 breaths from 35 patients with acute respiratory distress syndrome (ARDS) or ARDS risk factors. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients received continuous esophageal manometry. Ventilator dyssynchrony was identified using a machine learning algorithm. Mixed-effect models predicted V t , ΔP L,dyn , and transpulmonary mechanical energy for each type of ventilator dyssynchrony while controlling for repeated measures. Finally, we described how V t , positive end-expiratory pressure (PEEP), and sedation (Richmond Agitation-Sedation Scale) strategies modify ventilator dyssynchrony's association with these surrogate markers of lung stress and strain. Double-triggered breaths were associated with the most significant increase in V t , ΔP L,dyn , and transpulmonary mechanical energy. However, flow-limited, early reverse-triggered, and early ventilator-terminated breaths were also associated with significant increases in V t , ΔP L,dyn , and energy. The potential of a ventilator dyssynchrony type to increase V t , ΔP L,dyn , or energy clustered similarly. Increasing set V t may be associated with a disproportionate increase in high-volume and high-energy ventilation from double-triggered breaths, but PEEP and sedation do not clinically modify the interaction between ventilator dyssynchrony and surrogate markers of lung stress and strain. CONCLUSIONS: Double-triggered, flow-limited, early reverse-triggered, and early ventilator-terminated breaths are associated with increases in V t , ΔP L,dyn , and energy. As flow-limited breaths are more than twice as common as double-triggered breaths, further work is needed to determine the interaction of ventilator dyssynchrony frequency to cause clinically meaningful changes in patient outcomes.

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OBJECTIVE: To evaluate the agreement between the Tafonius large animal ventilator-integrated volumetric capnography (vCap) software and the Respironics NICO noninvasive cardiac output monitor reference system. ANIMALS: Data were collected from 56 healthy adult horses undergoing general anesthesia. METHODS: Animals were placed under general anesthesia and connected to the Tafonius large animal ventilator circle system. A flow partitioning device with CO2 and flow sensors was utilized to couple the endotracheal tube to the NICO monitor. Tafonius CO2 and flow sensors are incorporated into the Y-piece of the breathing circuit. Arterial blood samples were collected to determine the partial pressure of arterial carbon dioxide (PaCO2) immediately before data collection. The PaCO2 was input into the Tafonius and NICO monitor, and dead space ventilation (%Vd), end-tidal CO2 partial pressure (ETco2), mixed-expired CO2 partial pressure (Peco2), and expired tidal volume (Vt) were calculated over a single breath. Multiple measurements were completed for each patient, with a total of 200 paired data points collected for analysis. Data were assessed for normality, and Bland-Altman analysis was performed. Bias and 95% limits of agreement were calculated. RESULTS: The limits of agreement for %Vd of the ventilator-derived measurements fell within ± 10% of the NICO monitor reference method. CLINICAL RELEVANCE: Our results indicate that, when compared to the NICO monitor method, the Tafonius-integrated vCap software provides clinically acceptable values of Peco2, Vt, and %Vd in healthy adult horses.

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BACKGROUND: Ventilation configurations are of great clinical importance for adequate outcomes in mechanically ventilated patients, and they may even be used as specific physical therapy techniques. OBJECTIVES: To compare the effectiveness of lung hyperinflation through mechanical ventilation (HMV) with HMV plus flow bias optimization regarding respiratory mechanics, hemodynamics, and volume of secretion. METHODS: Patients mechanically ventilated > 24 h were included in this randomized crossover clinical trial. The following techniques were applied: HMV alone (control group) and HMV plus flow bias optimization (intervention group). RESULTS: The 20 included patients underwent both techniques, totaling 40 collections. A total of 52 % were women, the mean age was 60.8 (SD, 15.7) years, and the mean mechanical ventilation time was 4.3 (SD, 3.0) days. The main cause of mechanical ventilation was sepsis (44 %). Expiratory flow bias in optimized HMV was higher. than conventional HMV (p < 0.001). The volume of tracheal secretions collected was higher during optimized than conventional HMV. (p = 0.012). Significant differences in peak flow occurred at the beginning of the technique and a there was a significant decrease in respiratory system resistance immediately and 30 min after applying the technique in the intervention group. CONCLUSIONS: The volume of tracheal secretions collected was higher during optimized HMV, and, HMV with flow bias optimization resulted in lower respiratory system resistance and flow peaks and produced expiratory flow bias.

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OBJECTIVE: To evaluate whether a high cumulative dose of systemic hydrocortisone affects brain development compared with placebo when initiated between 7 and 14 days after birth in ventilated infants born preterm. STUDY DESIGN: A double-blind, placebo-controlled, randomized trial was conducted in 16 neonatal intensive care units among infants born at <30 weeks of gestation or with a birth weight of <1250 g who were ventilator-dependent in the second week after birth. Three centers performed MRI at term-equivalent age. Brain injury was assessed on MRI using the Kidokoro scoring system and compared between the 2 treatment groups. Both total and regional brain volumes were calculated using an automatic segmentation method and compared using multivariable regression analysis adjusted for baseline variables. RESULTS: From the 3 centers, 78 infants participated in the study and 59 had acceptable MRI scans (hydrocortisone group, n = 31; placebo group, n = 28). Analyses of the median global brain abnormality score of the Kidokoro score showed no difference between the hydrocortisone and placebo groups (median, 7; IQR, 5-9 vs median, 8, IQR, 4-10, respectively; P = .92). In 39 infants, brain tissue volumes were measured, showing no differences in the adjusted mean total brain tissue volumes, at 352 ± 32 mL in the hydrocortisone group and 364 ± 51 mL in the placebo group (P = .80). CONCLUSIONS: Systemic hydrocortisone started in the second week after birth in ventilator-dependent infants born very preterm was not found to be associated with significant differences in brain development compared with placebo treatment. TRIAL REGISTRATION: The SToP-BPD study was registered with the Netherlands Trial Register (NTR2768; registered on 17 February 2011; https://www.trialregister.nl/trial/2640) and the European Union Clinical Trials Register (EudraCT, 2010-023777-19; registered on 2 November 2010; https://www.clinicaltrialsregister.eu/ctr-search/trial/2010-023777-19/NL).

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Introdução: Pacientes com câncer apresentaram risco de desenvolver quadros respiratórios graves quando acometidos por covid-19, com necessidade de suporte intensivo e de ventilação mecânica invasiva (VMI). Objetivo: Avaliar os fatores associados ao óbito em pacientes oncológicos que tiveram covid-19 e evoluíram com insuficiência respiratória e necessidade de VMI. Método: Estudo de coorte retrospectivo de pacientes com câncer em uma unidade de terapia intensiva (UTI) oncológica, com covid-19 e em VMI de abril de 2020 a dezembro de 2021. Foram incluídos de forma sequencial todos os pacientes com câncer admitidos na UTI em VMI ou que evoluíram com VMI por agravamento da covid-19, sendo excluídos aqueles em controle da doença oncológica há mais de cinco anos. Para a análise estatística, foram utilizadas medidas de tendência central e dispersão, assim como frequências absolutas e relativas. A regressão logística múltipla foi aplicada para a avaliação dos fatores associados à mortalidade, considerando estatisticamente significantes valores de p < 0,05. Resultados: Foram incluídos no estudo 85 pacientes. O óbito foi maior entre os pacientes com tumores sólidos (OR = 3,64; IC 95%: 1,06-12,52; p = 0,04), entre os que necessitaram de suporte renal durante a internação na UTI (OR = 6,88; IC 95%: 1,82-25,98; p = 0,004), os que não puderam ser extubados (OR = 8,00; IC 95%: 2,16-29,67; p = 0,002) e os que apresentaram o valor de pressão de distensão alveolar maior do que 15cmH2O por pelo menos um dia (OR = 5,9; IC 95%: 1,76-19,80; p = 0,004). Conclusão: Características clínicas e de VMI estavam associadas à morte de pacientes oncológicos com covid-19 e em VMI.

Los pacientes con cáncer corrían riesgo de desarrollar afecciones respiratorias graves al ser afectados por la COVID-19, requiriendo soporte intensivo y ventilación mecánica invasiva (VMI). Objetivo: Evaluar los factores asociados a la muerte en pacientes con cáncer que tuvieron COVID-19 y que desarrollaron insuficiencia respiratoria y necesidad de VMI. Método: Estudio de cohorte retrospectivo en pacientes oncológicos internados en una unidad de cuidados intensivos (UCI) de oncología, con COVID-19 y en VMI de abril de 2020 a diciembre de 2021. Se incluyeron secuencialmente todos los pacientes con cáncer ingresados en UCI con VMI o que necesitaron VMI por empeoramiento de la COVID-19, excluyendo a aquellos que llevaban más de cinco años bajo control de la enfermedad oncológica. Para el análisis estadístico se utilizaron medidas de tendencia central y dispersión, así como frecuencias absolutas y relativas. Se aplicó regresión logística múltiple para evaluar los factores asociados a la mortalidad, considerando valores de p<0,05 estadísticamente significativos. Resultados: Se incluyeron en el estudio 85 pacientes. La muerte fue mayor entre los pacientes con tumores sólidos (OR= 3,64; IC 95%, 1,06-12,52; p=0,04), entre los que requirieron soporte renal durante la estancia en UCI (OR = 6,88; IC 95%, 1,82-25,98; p= 0,004), entre los que no pudieron ser extubados (OR= 8,00; IC 95%, 2,16-29,67; p= 0,002) y entre los que presentaron un valor de presión de distensión alveolar mayor a 15cmH2O durante al menos un día (OR = 5,9; IC 95%, 1,76-19,80; p=0,004). Conclusión: Las características clínicas y de VMI se asociaron con la muerte en pacientes oncológicos con COVID-19 y en VMI.

Cancer patients were at risk of developing severe respiratory conditions when affected by COVID-19, requiring intensive support and invasive mechanical ventilation (IMV). Objective: Evaluate the factors associated with death of cancer patients by COVID-19 who developed respiratory failure and need of IMV. Method: Retrospective cohort study of cancer patients in an oncology intensive care unit (ICU), with COVID-19 and on IMV was carried out from April 2020 to December 2021. All patients with cancer admitted to the ICU on IMV or who developed IMV due to worsening of COVID-19 were sequentially included, excluding those who had been in follow-up of the oncological disease for more than five years. For statistical analysis, measures of central tendency and dispersion were used, as well as absolute and relative frequencies. Multiple logistic regression was applied to evaluate factors associated with mortality, considering statistically significant values of p < 0.05. Results: 85 patients were included in the study. Death was higher for patients with solid tumors (OR= 3.64; 95% CI, 1.06-12.52; p = 0.04), in addition to those who required renal support while in ICU (OR = 6.88; 95% CI, 1.82-25.98; p = 0.004), those who could not be extubated (OR= 8.00; 95% CI, 2.16-29.67; p = 0.002) and who presented an alveolar distension pressure value greater than 15cmH2O for at least one day (OR= 5.9; 95% CI, 1.76-19.80; p = 0.004). Conclusion:Clinical and IMV characteristics were associated with death in cancer patients with COVID-19 and IMV

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This paper presents a practical application of health technology assessment for 21 mechanical ventilators, located at a secondary care Hospital in the State of Mexico, Mexico. A global indicator is obtained, by using a mathematical tool, which involves 14 variables grouped into three partial indicators: technical, clinical and economic. The final aim of this approach is to provide evidence for decision-making, in order to prioritize the replacement of medical equipment, taking into consideration its performance features, the needs of demand for care, and the economic implications for the Hospital.Clinical Relevance-Invasive Mechanical Ventilation (IMV), is a clinical procedure which implies a total or partial replacement of lung function. Given the life support implications, it is important to assure security and reliability in medical equipment intended for this therapy. Therefore, in order to keep updated the IMV devices, in addition to requiring preventive maintenance programs, medical technology replacement programs are necessary.

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INTRODUCTION: Certain criteria for ventilator-associated events (VAE) definition might influence the type of an event, its detection rate and consequently the resource expenditure in intensive care unit. The Impact of Infections by Antimicrobial-Resistant Microorganisms - Ventilator-Associated Pneumonia (IMPACTO MR-PAV) aims to evaluate the incidence and diagnostic accuracy of ventilator-associated pneumonia (VAP) using the current criteria for VAP surveillance in Brazil versus the VAE criteria defined by the US National Healthcare Safety Network-Center for Diseases Control and Prevention (CDC) criteria. METHODS AND ANALYSIS: The study will be conducted in around 15 centres across Brazil from October 2022 to December 2023. Trained healthcare professionals will collect data and compare the incidence of VAP using both the current criteria for VAP surveillance in Brazil and the VAE criteria defined by the CDC. The accuracy of the two criteria for identifying VAP will also be analysed. It will also characterise other events associated with mechanical ventilation (ventilator-associated condition, infection-related ventilator-associated complication) and adjudicate VAP reported to the Brazilian Health Regulatory Agency (ANVISA) using current epidemiological diagnostic criteria. ETHICS AND DISSEMINATION: This study was approved by the Institutional Review Board under the number 52354721.0.1001.0070. The study's primary outcome measure will be the incidence of VAP using the two different surveillance criteria, and the secondary outcome measures will be the accuracy of the two criteria for identifying VAP and the adjudication of VAP reported to ANVISA. The results will contribute to the improvement of VAP surveillance in Brazil and may have implications for other countries that use similar criteria. TRIAL REGISTRATION NUMBER: NCT05589727; Clinicaltrials.gov.

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The viscoelastic properties of the lung have important implications during respiratory mechanics in terms of lung movement or work of breathing, for example. However, this property has not been well characterized due to several reasons, such as the complex nature of the lung, difficulty accessing its tissues, and the lack of physical simulators that represent viscoelastic effects. This research proposes an electropneumatic system and a method to simulate the viscoelastic effect from temporary forces generated by the opposition of magnetic poles. The study was tested in a mechanical ventilation scenario with inspiratory pause, using a Hamilton-S1 mechanical ventilator (Hamilton Medical) and a simulator of the human respiratory system (SAMI-SII). The implemented system was able to simulate the stress relaxation response of a Standard Linear Solid model in the Maxwell form and showed the capacity to control elastic and viscous parameters independently. To the best of our knowledge, this is the first system incorporated into a physical lung simulator that represents the viscoelastic effect in a mechanical ventilation scenario.

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