Prediction and simulation of PEEP setting effects with machine learning models / Predicción y simulación de los efectos de la configuración de la PEEP con modelos de aprendizaje automático

Objective To establish a new machine learning-based method to adjust positive end-expiratory pressure (PEEP) using only already routinely measured data. Design Retrospective observational study. Setting Intensive care unit (ICU). Patients or participants 51811 mechanically ventilated patients in multiple ICUs in the USA (data from MIMIC-III and eICU databases). Interventions No interventions. Main variables of interest Success parameters of ventilation (arterial partial pressures of oxygen and carbon dioxide and respiratory system compliance). Results The multi-tasking neural network model performed significantly best for all target tasks in the primary test set. The model predicts arterial partial pressures of oxygen and carbon dioxide and respiratory system compliance about 45 min into the future with mean absolute percentage errors of about 21.7%, 10.0% and 15.8%, respectively. The proposed use of the model was demonstrated in case scenarios, where we simulated possible effects of PEEP adjustments for individual cases. Conclusions Our study implies that machine learning approach to PEEP titration is a promising new method which comes with no extra cost once the infrastructure is in place. Availability of databases with most recent ICU patient data is crucial for the refinement of prediction performance. (AU)

Objetivo Establecer un nuevo método basado en el aprendizaje automático para ajustar la presión positiva al final de la espiración (PEEP según sus siglas en inglés) utilizando únicamente datos ya obtenidos de forma rutinaria. Diseño Estudio retrospectivo de observación. Ámbito Unidad de cuidados intesivos (UCI) Pacientes o participantes 51811 pacientes ventilados mecánicamente en múltiples UCIs de EE.UU. (tomados de las bases de datos MIMIC-III y eICU). Intervenciones Sin intervenciones. Variables de interés principales Parametros de éxito de la ventilación (presiones parciales arteriales de oxígeno y dióxido de carbono y distensibilidad del sistema respiratorio). Resultados El modelo de red neuronal multitarea obtuvo los mejores resultados en todos los objetivos del conjunto de pruebas primario. El modelo predice las presiones parciales arteriales de oxígeno y dióxido de carbono así como la distensibilidad del sistema respiratorio con aproximadamente 45 minutos de anticipación, mostrando errores porcentuales absolutos medios de aproximadamente 21.7%, 10.0% y 15.8%, respectivamente. El uso propuesto del modelo se demostró en situaciones hipotéticas en las que se simularon los posibles efectos de los ajustes de PEEP para casos individuales. Conclusiones Nuestro estudio implica que el enfoque de aprendizaje automático para el ajuste de la PEEP es un método nuevo y prometedor que no supone ningún coste adicional una vez que se dispone de la infraestructura necesaria. La disponibilidad de bases de datos con información de pacientes de UCI más recientes es crucial para perfeccionar el rendimiento de la predicción. (AU)

Evaluation of an automatized AMBU ESSI-1 INC designed at the Instituto Nacional de Cardiología Ignacio Chávez.

OBJECTIVE: The objectives of this study were to evaluate an automated device for ventilatory support based on AMBU manufactured in March 2020. METHODS: The ESSI-1 INC was evaluated through pulmonary mechanics and physiology parameters through compensatory spirometer tests (TISSOTs), and an artificial lung Model5600i Dual Adult PNEU VIEW SYSTEM; it was also compared to the anesthetic ventilatory support equipment (AEONMED 7500) in porcine models, measuring ventilatory, hemodynamic and gasometric parameters. RESULTS: This equipment (ESSI-1 INC) was successfully tested by mechanical and biological models, such as pigs in which its performance was evaluated in terms of variability of tidal volume, ventilation frequency, and I/E relationship versus the manual performance of two medical interns. All the results turned out as expected and were satisfactory. CONCLUSIONS: It is safe and effective equipment and should be tested and used in diverse clinical conditions to standardize the ventilatory safety and care of patients who require it.

OBJETIVO: Evaluar un dispositivo automatizado para la asistencia ventilatoria basado en un AMBU manufacturado en Marzo del 2020. MÉTODOS: El ESSI-1 INC fue evaluado por medio de parámetros fisiológicos y mecánica pulmonar a través de pruebas de espirómetro compensatorios (TISSOT); pulmón artificial (Modelo 5600i Dual Adult PNEU VIEW SYSTEM); así como su desempeño comparado a la máquina de anestesia (AEONMED 7500) en modelos porcinos, midiendo criterios ventilatorios, hemodinámicos y gasométricos. RESULTADOS: Este equipo (ESSI-1 INC) fue exitosamente probado por modelos mecánicos y biológicos, tales como cerdos donde su desempeño fue evaluado en términos de la variabilidad del volumen tidal, frecuencia ventilatoria, y relación I/E versus el desempeño manual de dos médicos. Todos los resultados finalizaron como se esperaba de forma satisfactoria. CONCLUSIONES: Es un equipo seguro y efectivo, el cual debería ser probado y usado en distintas condiciones clínicas para estandarizar la seguridad ventilatoria y cuidado de pacientes que lo requieran.

Comparação de desfechos clínicos e correlação entre funcionalidade e tempo de ventilação mecânica de pacientes em uti / Comparison of clinical outcomes and correlation between functionality and time of mechanical ventilation in icu patients / Comparación de los resultados clínicos y correlación entre la funcionalidad y el tiempo de ventilación mecánica de los pacientes en uti

O objetivo deste estudo foi comparar os desfechos clínicos dos pacientes em suporte ventilatório invasivo por período curto e prolongado e correlacionar funcionalidade e tempo de ventilação mecânica (VM). Estudo documental retrospectivo, realizado na UTI neurocirúrgica de um hospital escola. Dos prontuários clínicos foram coletados: idade, sexo, hipótese diagnóstica de internação, tempo de internação e de VM em dias, o desfecho sucesso ou falha da extubação e o nível de funcionalidade. Os prontuários foram divididos em grupo um (GI): pacientes em VM por até três dias e grupo dois (GII): pacientes em VM por mais de três dias. Foram analisados 210 prontuários, 73% dos pacientes permaneceram menos de três dias em VM. A idade média de GI foi 51,8±15,5 anos e GII 48,7±16,3 anos (p=0,20), prevalência do sexo masculino em GI (59%) e GII (68%). O acidente vascular cerebral foi o diagnóstico mais prevalente no GI (18%) e o tumor cerebral no GII (21%) e hipertensão arterial, a comorbidade mais prevalente em GI (28%) e GII (25%). O GII permaneceu maior tempo (p<0,0001) em VM e internação na UTI que o GI e percentual de sucesso no desmame/extubação menor (p=0,01) que o GI. Não houve correlação significativa entre funcionalidade e tempo de VM em GI e GII (p>0,05). Os pacientes em suporte ventilatório invasivo por período prolongado evoluíram com maior permanência em VM, maior tempo de internação na UTI e menor taxa de sucesso no desmame/extubação. O tempo de permanência em suporte ventilatório invasivo não interferiu na funcionalidade desses pacientes.

The aim of this study was to compare the clinical outcomes of patients on short- and long-term invasive ventilatory support and to correlate functionality and duration of mechanical ventilation (MV). Retrospective documental study, carried out in the neurosurgical ICU of a teaching hospital. The following were collected from the clinical records: age, gender, diagnostic hypothesis of hospitalization, length of hospital stay and MV in days, the outcome of success or failure of extubation and the level of functionality. The medical records were divided into group one (GI): patients on MV for up to three days and group two (GII): patients on MV for more than three days. A total of 210 medical records were analyzed, 73% of the patients remained on MV for less than three days. The mean age of GI was 51.8±15.5 years and GII 48.7±16.3 years (p=0.20), male prevalence in GI (59%) and GII (68%). Stroke was the most prevalent diagnosis in GI (18%) and brain tumor in GII (21%) and hypertension was the most prevalent comorbidity in GI (28%) and GII (25%). GII remained longer (p<0.0001) in MV and ICU admission than GI and the percentage of success in weaning/extubation was lower (p=0.01) than GI. There was no significant correlation between functionality and time on MV in GI and GII (p>0.05). Patients on invasive ventilatory support for a long period evolved with longer MV stays, longer ICU stays and lower weaning/extubation success rates. The length of stay on invasive ventilatory support did not interfere with the functionality of these patients.

El objetivo de este estudio fue comparar los resultados clínicos de los pacientes con soporte ventilatorio invasivo a corto y largo plazo y correlacionar la funcionalidad y el tiempo de ventilación mecánica (VM). Se trata de un estudio documental retrospectivo, realizado en la UCI neuroquirúrgica de un hospital universitario. Se recogieron los siguientes datos de las historias clínicas: edad, sexo, hipótesis diagnóstica, duración de la estancia y tiempo de VM en días, el resultado éxito o fracaso de la extubación y el nivel de funcionalidad. Las historias clínicas se dividieron en el grupo uno (GI): pacientes bajo VM hasta tres días y el grupo dos (GII): pacientes bajo VM durante más de tres días. Se analizaron 210 historias clínicas, el 73% de los pacientes permanecieron menos de tres días con VM. La edad media de GI fue de 51,8±15,5 años y la de GII de 48,7±16,3 años (p=0,20), con prevalencia masculina en GI (59%) y GII (68%). El ictus fue el diagnóstico más prevalente en GI (18%) y el tumor cerebral en GII (21%) y la hipertensión, la comorbilidad más prevalente en GI (28%) y GII (25%). El GII permaneció más tiempo (p<0,0001) en la VM y la estancia en la UCI que el GI y el porcentaje de éxito en el destete/extubación fue menor (p=0,01) que el GI. No hubo correlación significativa entre la funcionalidad y el tiempo de VM en GI y GII (p>0,05). Los pacientes con soporte ventilatorio invasivo a largo plazo evolucionaron con una mayor estancia en la VM, una mayor estancia en la UCI y una menor tasa de éxito de destete/extubación. La duración de la estancia con soporte ventilatorio invasivo no interfirió en la funcionalidad de estos pacientes.

Biological evaluation of a mechanical ventilator that operates by controlling an automated manual resuscitator. A descriptive study in swine.

The Covid-19 outbreak challenged health systems around the world to design and implement cost-effective devices produced locally to meet the increased demand of mechanical ventilators worldwide. This study evaluates the physiological responses of healthy swine maintained under volume- or pressure-controlled mechanical ventilation by a mechanical ventilator implemented to bring life-support by automating a resuscitation bag and closely controlling ventilatory parameters. Physiological parameters were monitored in eight sedated animals (t0) prior to inducing deep anaesthesia, and during the next six hours of mechanical ventilation (t1-7). Hemodynamic conditions were monitored periodically using a portable gas analyser machine (i.e. BEecf, carbonate, SaO2, lactate, pH, PaO2, PaCO2) and a capnometer (i.e. ETCO2). Electrocardiogram, echocardiography and lung ultrasonography were performed to detect in vivo alterations in these vital organs and pathological findings from necropsy were reported. The mechanical ventilator properly controlled physiological levels of blood biochemistry such as oxygenation parameters (PaO2, PaCO2, SaO2, ETCO2), acid-base equilibrium (pH, carbonate, BEecf), and perfusion of tissues (lactate levels). In addition, histopathological analysis showed no evidence of acute tissue damage in lung, heart, liver, kidney, or brain. All animals were able to breathe spontaneously after undergoing mechanical ventilation. These preclinical data, supports the biological safety of the medical device to move forward to further evaluation in clinical studies.

OxVent: Design and evaluation of a rapidly-manufactured Covid-19 ventilator.

BACKGROUND: The manufacturing of any standard mechanical ventilator cannot rapidly be upscaled to several thousand units per week, largely due to supply chain limitations. The aim of this study was to design, verify and perform a pre-clinical evaluation of a mechanical ventilator based on components not required for standard ventilators, and that met the specifications provided by the Medicines and Healthcare Products Regulatory Agency (MHRA) for rapidly-manufactured ventilator systems (RMVS). METHODS: The design utilises closed-loop negative feedback control, with real-time monitoring and alarms. Using a standard test lung, we determined the difference between delivered and target tidal volume (VT) at respiratory rates between 20 and 29 breaths per minute, and the ventilator's ability to deliver consistent VT during continuous operation for >14 days (RMVS specification). Additionally, four anaesthetised domestic pigs (3 male-1 female) were studied before and after lung injury to provide evidence of the ventilator's functionality, and ability to support spontaneous breathing. FINDINGS: Continuous operation lasted 23 days, when the greatest difference between delivered and target VT was 10% at inspiratory flow rates >825 mL/s. In the pre-clinical evaluation, the VT difference was -1 (-90 to 88) mL [mean (LoA)], and positive end-expiratory pressure (PEEP) difference was -2 (-8 to 4) cmH2O. VT delivery being triggered by pressures below PEEP demonstrated spontaneous ventilation support. INTERPRETATION: The mechanical ventilator presented meets the MHRA therapy standards for RMVS and, being based on largely available components, can be manufactured at scale. FUNDING: Work supported by Wellcome/EPSRC Centre for Medical Engineering,King's Together Fund and Oxford University.

Tocilizumab in critically ill COVID-19 patients: An observational study.

Tocilizumab decreases inflammatory response in the cytokine storm which is one of the mechanisms behind the development of ARDS in COVID-19 patients. The objective of our study was to determine response of tocilizumab in patients suffering from COVID-19 by analyzing clinical parameters and inflammatory markers. A single-arm observational retrospective study was conducted from March 15, 2020 to March 15, 2021. Clinical outcomes in terms of mortality, weaning from mechanical ventilator, improvement in laboratory parameters including inflammatory cytokines, and length of hospital stay were documented. Reduction in values of inflammatory markers, and patients discharged home in stable condition were defined as an improvement after tocilizumab administration. A total of 514 patients received tocilizumab, majority of whom were critically sick 333 (64.8%). Out of the total sample 363 (70.6%) patients were discharged home in stable condition. Overall mean length of stay was 11.50 ± 8.4 days. There was significant difference in length of stay of patients who required invasive mechanical ventilation as compared to those who were kept only on supplemental oxygen (p < 0.05). Patients who were discharged home showed significant improvement in inflammatory markers and neutrophil to lymphocyte ratio as compared to those who expired (p < 0.05). A total of 21 (4.1%) patients had positive blood culture while 57 (11.1%) had positive culture of tracheal aspirate. Hence, tocilizumab is found to be a reasonable therapeutic option for worsening COVID-19 pneumonia by decreasing the need for mechanical ventilation. However, it is associated with adverse events including bacterial and fungal infections.

Comparison of two devices for automated oxygen control in preterm infants: a randomised crossover trial.

OBJECTIVE: To compare the effect of two different automated oxygen control devices on target range (TR) time and occurrence of hypoxaemic and hyperoxaemic episodes. DESIGN: Randomised cross-over study. SETTING: Tertiary level neonatal unit in the Netherlands. PATIENTS: Preterm infants (n=15) born between 24+0 and 29+6 days of gestation, receiving invasive or non-invasive respiratory support with oxygen saturation (SpO2) TR of 91%-95%. Median gestational age 26 weeks and 4 days (IQR 25 weeks 3 days-27 weeks 6 days) and postnatal age 19 (IQR 17-24) days. INTERVENTIONS: Inspired oxygen concentration was titrated by the OxyGenie controller (SLE6000 ventilator) and the CLiO2 controller (AVEA ventilator) for 24 hours each, in a random sequence, with the respiratory support mode kept constant. MAIN OUTCOME MEASURES: Time spent within set SpO2 TR (91%-95% with supplemental oxygen and 91%-100% without supplemental oxygen). RESULTS: Time spent within the SpO2 TR was higher during OxyGenie control (80.2 (72.6-82.4)% vs 68.5 (56.7-79.3)%, p<0.005). Less time was spent above TR while in supplemental oxygen (6.3 (5.1-9.9)% vs 15.9 (11.5-30.7)%, p<0.005) but more time spent below TR during OxyGenie control (14.7 (11.8%-17.2%) vs 9.3 (8.2-12.6)%, p<0.05). There was no significant difference in time with SpO2 <80% (0.5 (0.1-1.0)% vs 0.2 (0.1-0.4)%, p=0.061). Long-lasting SpO2 deviations occurred less frequently during OxyGenie control. CONCLUSIONS: The OxyGenie control algorithm was more effective in keeping the oxygen saturation within TR and preventing hyperoxaemia and equally effective in preventing hypoxaemia (SpO2 <80%), although at the cost of a small increase in mild hypoxaemia. TRIAL REGISTRY NUMBER: NCT03877198.

Fluid Balance and Ventilator-Associated Events Among Patients Admitted to ICUs in China: A Nested Case-Control Study.

OBJECTIVES: Fluid therapy is an important component of intensive care management, however, optimal fluid management is unknown. The relationship between fluid balance and ventilator-associated events has not been well established. This study investigated the dose-response relationship between fluid balance and ventilator-associated events. DESIGN: Nested case-control study. SETTING: The study was based on a well-established, research-oriented registry of healthcare-associated infections at ICUs of West China Hospital system (Chengdu, China). PATIENTS: A total of 1,528 ventilator-associated event cases with 3,038 matched controls, who consistently underwent mechanical ventilation for at least 4 days from April 1, 2015, to December 31, 2018, were included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We calculated cumulative fluid balance within 4 days prior to ventilator-associated event occurrence. A weighted Cox proportional hazards model with restricted cubic splines was used to evaluate the dose-response relationship. A nonlinear relationship between fluid balance and all three tiers of ventilator-associated events, patients with fluid balance between -1 and 0 L had the lowest risk (p < 0.05 for nonlinear test). The risk of ventilator-associated event was significantly higher in patients with positive fluid balance (4 d cumulative fluid balance: 1 L: 1.19; 3 L: 1.92; 5 L: 2.58; 7 L: 3.24), but not in those with negative fluid balance (-5 L: 1.34; -3 L: 1.14; -1 L: 0.98). CONCLUSIONS: There was nonlinear relationship between fluid balance and all three tiers of ventilator-associated event, with an fluid balance between -1 and 0 L corresponding to the lowest risk. Positive but not negative fluid balance increased the risk of ventilator-associated events, with higher positive fluid balance more likely to lead to ventilator-associated events.

RAM cannula with Cannulaide versus Hudson prongs for delivery of nasal continuous positive airway pressure in preterm infants: an RCT.

Nasal continuous positive airway pressure (nCPAP) is the standard non-invasive respiratory support for newborns with respiratory distress. Nasal injury is a common problem with the interfaces used. To compare the incidence and severity of nasal injury in neonates with respiratory distress and supported on nCPAP with Hudson prong or RAM cannula with Cannulaide, a semipermeable membrane. This is an open-label, parallel-arm, gestational age-stratified, bi-centric, randomized control trial including neonates between 28 and 34 weeks gestational age and birth weight > 1000 g needing nCPAP. The size of the interface was chosen as per the manufacturer's recommendation. Of the 229 neonates enrolled, 112 were randomized to RAM cannula with Cannulaide and 117 to Hudson prong. The baseline characteristics were similar. Any nasal injury at CPAP removal was significantly lower in the RAM cannula with Cannulaide group [6 (5.4%) vs. 31 (26.4%); risk ratio-0.77 (95% CI 0.69-0.87); p = 0.0001]. The incidence of moderate to severe nasal injury, need for mechanical ventilation within 72 h of age, duration of oxygen, and requirement of nCPAP for > 3 days were similar. For preterm infants on nCPAP, RAM cannula with Cannulaide, compared to Hudson prongs, decreases nasal injury without increasing the need for mechanical ventilation.Trail registration: CTRI/2019/03/018333, http://www.ctri.nic.in .

Modos ventilatorios usados en pacientes críticos con covid-19 en la región de Lombardía, Italia / Ventilation modes used in critical patient with COVID-19 in the region of Lombardy, Italy

RESUMEN Introducción: la covid-19 es una enfermedad donde la ventilación mecánica artificial cobra vital importancia. Se estima que el 50 % de los casos graves o críticos que requieren manejo en unidades de cuidados intensivos fallecen. Objetivos: se evaluó el impacto de los modos ventilatorios usados en pacientes con covid-19 en Lombardía, Italia, en la oxigenación, la hemodinámica y la mortalidad. Materiales y métodos: se realizó un estudio analítico longitudinal retrospectivo en 86 pacientes críticos con covid-19, en el Hospital Mayor de Crema, en Lombardía, Italia, desde el 1 de abril al 20 de mayo de 2020. Se realizaron análisis no paramétrico y de la varianza. Resultados: Hubo una supervivencia del 76,7 %. El modo utilizado tuvo igual comportamiento en occisos (BiPAP-3, PCV-4, VCRP-4, APRV-5, VCV-4) y en vivos (BiPAP-10, PCV-17, VCRP-14, APRV-15, VCV-10); test de x2 = 0,59; test de análisis de la varianza media índice PO2/FIO2 (PCV = 132), (BiPAP = 132) (VCV = 115) p = 0,924. La presión de final de espiración positiva (BiPAP-12, PCV-13, VCRP-13, APRV-13, VCV-14) con p = 0,205. PCO2 (BiPAP-55, PCV-52, VCRP-57, APRV-59, VCV-57) con p = 0,512. La tensión arterial media (BiPAP-84, PCV-83, VCRP-84, APRV-82, VCV-83) con p = 0,988. Modelos de cálculo de la presión de final de espiración positiva, según modo ventilatorio: BiPAP: PEEP = -0,0331 (índice PO2/FiO2) +18,215; PCV: PEEP = -0,0047 (índice PO2/FiO2) +13,717; VCRP: PEEP = -0,0204 (índice PO2/FiO2) +15,678; APRV: PEEP = -0,0092 (índice PO2/FiO2) +14,889. Conclusiones: la evolución del paciente crítico con covid-19 está determinada en gran medida por la ventilación mecánica invasiva; sin embargo, no existió suficiente evidencia para recomendar una u otra modalidad ventilatoria. El éxito está en conocer con exactitud las características del respirador, su modalidad y el paciente en cuestión. (AU)

ABSTRACT Introduction: COVID-19 is a disease in which mechanical ventilation acquires vital importance. It is estimated that 50 % of the serious and critical patients requiring management in intensive care units die. Objectives: to assess the impact of the ventilation modes used in patients with COVID-19 in Lombardy, Italy, on oxygenation, hemodynamics and mortality. Materials and methods: a retrospective, longitudinal, analytic study was carried out in 86 critical patients with COVID-19 who entered the Main Hospital of Crema, in Lombardy, Italy, from April 1st to May 20, 2020. Results: the survival was 76.7 %. The used mode showed the same behavior in deceased patients (BiPAP-3, PCV-4, VCRP-4, APRV-5, VCV-4) and in alive patients (BiPAP-10, PCV-17, VCRP-14, APRV-15, VCV-10). X2 = 0.59. ANOVA test index PO2/FIO2 (PCV = 132), (BiPAP = 132) (VCV=115) p = 0.924. PEEP (BiPAP-12, PCV-13, VCRP-13, APRV-13, VCV-14) p = 0.205. PCO2 (BiPAP-55, PCV-52, VCRP-57, APRV-59, VCV-57) p = 0.512. Average blood pressure (BiPAP-84, PCV-83, VCRP-84, APRV-82, VCV-83) p = 0.988. PEEP models according to ventilation mode: BiPAP: PEEP = -0.0331 (PO2/FiO2 index) +18.215. PCV: PEEP = -0.0047 (PO2/FiO2 index) + 13.717; VCRP: PEEP = -0.0204 (PO2/FiO2 index) + 15.678; APRV: PEEP = -0.0092 (PO2/FiO2 index) +14.889. Conclusion: the evolution of the critical patient with COVID-19 is determined mostly by the invasive mechanical ventilation; but we did not find evidence enough to recommend one or the other ventilation mode. The success stands in knowing accurately the characteristics of the ventilator, the ventilation modes and the patient (AU).

Removal of a catheter mount and heat-and-moisture exchanger improves hypercapnia in patients with acute respiratory distress syndrome: A retrospective observational study.

ABSTRACT: To avoid ventilator-associated lung injury in acute respiratory distress syndrome (ARDS) treatment, respiratory management should be performed at a low tidal volume of 6 to 8 mL/kg and plateau pressure of ≤30 cmH2O. However, such lung-protective ventilation often results in hypercapnia, which is a risk factor for poor outcomes. The purpose of this study was to retrospectively evaluate the effectiveness and safety of the removal of a catheter mount (CM) and using heated humidifiers (HH) instead of a heat-and-moisture exchanger (HME) for reducing the mechanical dead space created by the CM and HME, which may improve hypercapnia in patients with ARDS.This retrospective observational study included adult patients with ARDS, who developed hypercapnia (PaCO2 > 45 mm Hg) during mechanical ventilation, with target tidal volumes between 6 and 8 mL/kg and a plateau pressure of ≤30 cmH2O, and underwent stepwise removal of CM and HME (replaced with HH). The PaCO2 values were measured at 3 points: ventilator circuit with CM and HME (CM + HME) use, with HME (HME), and with HH (HH), and the overall number of accidental extubations was evaluated. Ventilator values (tidal volume, respiratory rate, minutes volume) were evaluated at the same points.A total of 21 patients with mild-to-moderate ARDS who were treated under deep sedation were included. The values of PaCO2 at HME (52.7 ±â€Š7.4 mm Hg, P < .0001) and HH (46.3 ±â€Š6.8 mm Hg, P < .0001) were significantly lower than those at CM + HME (55.9 ±â€Š7.9 mm Hg). Measured ventilator values were similar at CM + HME, HME, and HH. There were no cases of reintubation due to accidental extubation after the removal of CM.The removal of CM and HME reduced PaCO2 values without changing the ventilator settings in deeply sedated patients with mild-to-moderate ARDS on lung-protective ventilation. Caution should be exercised, as the removal of a CM may result in circuit disconnection or accidental extubation. Nevertheless, this intervention may improve hypercapnia and promote lung-protective ventilation.

An automatic water-occluding device to enable laryngectomee participation in water activities.

Individuals with a laryngectomy face a host of challenges ranging from restricted vocal communication to significant lifestyle modifications associated with breathing through a stoma. Although there are significant mental and physical health benefits achieved by returning to recreational pursuits that were enjoyed pre-surgery, there can be significant obstacles in doing so. One particular challenge arises during participation in water activities (e.g, fishing, boating, etc.) where accidental submersion poses a significant risk of drowning. This manuscript describes a proof-of-concept device that protects the airway from accidental incursion of water into the airway during unanticipated submersion in water, thereby allowing laryngectomees to return to participation in water activities. The device is designed to be worn comfortably for long periods of time, while not interfering with the common methods of replacement speech that are utilized post-laryngectomy.

Cuidados de enfermagem na prevenção da pneumonia associada à ventilação mecânica / Nursing care in preventing pneumonia associated with mechanical ventilationt / Atención de enfermería en la prevención de la neumonía associada a la ventilación mecânica

Introdução:A ventilação mecânica invasiva é um recurso terapêutico artificial, que possui a finalidade de equilíbrio da ventilação e/ou oxigenação de pacientes com insuficiência respiratória, entre as complicações desta intervenção, destaca-se a pneumonia. Nesse âmbito, o enfermeiro tem um papel primordial na criação de programas de prevenção das infecções, sobretudo na precaução da pneumonia associada à ventilação mecânica nas unidades de terapia intensiva. Objetivo:Descrever as ações de enfermagem para prevenção da pneumonia associada à ventilação mecânica invasiva na Unidade de Terapia Intensiva. Metodologia:Trata-se de um estudo do tipo revisão integrativa da literatura, para qual, definiu-se como ambiente de pesquisa as bases de dados BDENF, LILACS e MEDLINE. Elencou-se artigos publicados nos idiomas português, inglês e espanhol no período entre 2015 a 2019. Explorou-se os artigos a partir dos parâmetros estabelecidos pelo guia PRISMA, verificação dos títulos, resumos e texto completo, considerando os estudos que estivessem de acordo com o objetivo proposto, sendo selecionados 7 artigos para compor esta revisão. Resultados:Observou-se nos artigos analisadosa importância da adesão de ferramentas de ações no processo de cuidado, como os protocolos e bundles (um conjunto de medidas e intervenções) de prevenção da pneumonia associada à ventilação mecânica, para quais compreendem práticas como a verificação da pressão do cuff, elevação da cabeceira, aspiração de secreção, higiene oral, validade dos artigos médicos, lavagens das mãos e a interrupção da infusão de sedativos. Conclusões:Preconiza-se a adesão de medidas preventivas da pneumonia associada à ventilação mecânica nas unidades de terapia intensiva, as quais precisam ser praticadas rigorosamente pelos profissionais de enfermagem, por serem representantes do cuidado. Ressalta-se a necessidade de atualizações e construções de protocolos com medidas que possam prevenir as infecções de trato respiratório oriundas do uso da ventilação mecânica invasiva (AU).

Introduction:Invasive mechanical ventilation is an artificial therapeutic resource, which aims to balance ventilation and / or oxygenation of patients with respiratory failure, among the complications of this intervention, pneumonia stands out. In this context, the nurse has a primary role in creating infection prevention programs, especially in the prevention of pneumonia associated with mechanical ventilation in intensive care units. Objective:To describe nursing actions to prevent pneumonia associated with invasivemechanical ventilation in the Intensive Care Unit.Methodology:This is a bibliographic study, of the type integrative literature review, for which the databases BDENF, LILACS and MEDLINE were defined as a research environment. Articles published in Portuguese, English and Spanish from 2015 to 2019 were listed. Articles were explored using the parameters established by the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guide, verification of titles, abstracts and full text, considering studies that were in accordance with the proposed objective, with 7 articles selected to compose this review. Results: It was observed in the analyzed articles the importance of adhering to action tools in the care process, such as protocols and bundles (a set of measures and interventions) for preventing pneumonia associated with mechanical ventilation, for which they comprise practices such as checking the cuff pressure, elevating the headboard, secretion aspiration , oral hygiene, validity of medical articles, hand washing and stopping the infusion of sedatives. Conclusions:Adherence to preventive measures for pneumonia associated with mechanical ventilation in intensive care units is recommended, which must be strictly practiced by nursing professionals, as they are representatives of care. The need to update and build protocols with measures that can prevent respiratory tract infections arising from the use of invasive mechanical ventilation is emphasized (AU).

Introducción:La ventilación mecánica invasiva es un recurso terapéutico artificial, con la finalidad de equilibrar la ventilación y / u oxigenación enpacientes con insuficiencia respiratoria, entre las complicaciones de esta intervención se destaca la neumonía. En este contexto, la enfermera es fundamental en la creación de programas de prevención de infecciones, especialmente en neumonía asociada a ventilador en unidades de cuidados intensivos. Objetivo:Describir las acciones de enfermería para prevenir la neumonía asociada a la ventilación mecánica invasiva en la Unidad de Cuidados Intensivos. Metodología:Se trata de una revisión integradora de la literatura, realizada a través de las bases de datos BDENF, LILACS y MEDLINE. Se enumeraron los artículos publicados en portugués, inglés y español en el período comprendido entre 2015 y 2019. Los artículos fueron explorados en base a los parámetros establecidos por la guía Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA), verificación de títulos, resúmenes y texto completo.,considerando los estudios que estaban de acuerdo con el objetivo propuesto, seleccionándose 7 artículos. Resultados:Se observó la importancia de la adherencia a herramientas de acción en el proceso de atención, como protocolos y paquetes (conjunto de medidas e intervenciones) para la prevención de la neumonía asociada al ventilador, que incluyen prácticas comoel control de la presión del paciente. manguito, elevación de la cabeza, aspiración de secreciones, higiene bucal, vigencia de artículos médicos, lavado de manos e interrupción de la infusión de sedantes. Conclusiones:Se recomienda la adherencia a las medidas preventivas, las cuales deben ser practicadas con rigor por los profesionales de enfermería, por ser representantes del cuidado. Se destaca la necesidad de actualización y construcción de protocolos con medidas que puedan prevenir las infecciones deltracto respiratorio derivadas del uso de ventilación mecánica invasiva (AU).

Evaluation of a mechanical lung model to test small animal whole body plethysmography.

Whole-body plethysmography (WBP) is an established method to determine physiological parameters and pathophysiological alteration of breathing in animals and animal models of a variety of diseases. Although frequently used, there is ongoing debate about what exactly is measured by whole-body-plethysmography and how reliable the data derived from this method are. Here, we designed an artificial lung model that enables a thorough evaluation of different predictions about and around whole-body plethysmography. Using our lung model, we confirmed that during WBP two components contribute to the pressure changes detected in the chamber: (1) the increase in the pressure due to heating and moistening of the air during inspiration, termed conditioning; (2) changes in the chamber pressure that depend on airway resistance. Both components overlap and contribute to the temporal pressure-profile measured in the chamber or across the wall of the chamber, respectively. Our data showed that a precise measurement of the breathing volume appears to be hindered by at least two factors: (1) the unknown relative contribution of each of these two components; (2) not only the air in the inspired volume is conditioned during inspiration, but also air within the residual volume and dead space that is recruited during inspiration. Moreover, our data suggest that the expiratory negative pressure peak that is used to determine the enhanced pause (Penh) parameter is not a measure for airway resistance as such but rather a consequence of the animal's response to the airway resistance, using forced or active expiration to overcome the resistance by a higher thoracic pressure.