Less Invasive Surfactant Administration (LISA) Versus INSURE Method in Preterm Infants: a Retrospective Study.

Background: Respiratory distress syndrome (RDS) is a major cause of morbidity and mortality in preterm infants. Early nasal CPAP and selective administration of surfactant via the endotracheal tube are widely used in the treatment of RDS in preterm infants. Objective: The aim of this study was to compare the need for intubation and mechanical ventilation after surfactant delivery between LISA-treated and INSURE-treated premature infants with respiratory distress syndrome (RDS). Methods: Retrospective registry-based cohort study enrolled 36 newborns admitted to the neonatal intensive care unit of the "Santa Maria" Hospital of Terni between 2016 and 2023. As a primary outcome, we followed the need for intubation and mechanical ventilation within 72 hours of life, while the secondary outcomes were major neonatal morbidities and death before discharge. Results: The LISA group and the INSURE group included 13 and 23 newborns respectively. Demographic features showed no significant differences between the two groups. The need for mechanical ventilation in the first 72 hours of life was similar in both groups (p >0.99). There were no significant differences in morbidities. Conclusion: LISA and INSURE are equally effective modalities for surfactant administration for the treatment of RDS in preterm infants.

The impact of combined administration of surfactant and intratracheal budesonide compared to surfactant alone on bronchopulmonary dysplasia (BPD) and mortality rate in preterm infants with respiratory distress syndrome: a single-blind randomized clinical trial.

BACKGROUND: Respiratory distress syndrome (RDS) is one of the most important and common disorders among premature infants. OBJECTIVE: This study aimed to compare the effect of the combination of surfactant and budesonide with surfactant alone on Bronchopulmonary dysplasia (BPD) and mortality rate among premature infants with RDS. METHOD: An outcome assessor-blind randomized clinical trial was conducted on 134 premature infants with RDS who were born in Ayatollah Mousavi Hospital, Zanjan, Iran in 2021. The covariate adaptive randomization method was utilized to allocate participants into two groups (surfactant alone and a combination of surfactant and budesonide). The primary outcomes were BPD and Mortality rate from admission to hospital discharge. The data in this study were analyzed using SPSS software version 18. RESULTS: Overall the comparison of mortality rate and BPD between the two groups did not show a significant difference(p > 0.05). The subgroup results showed that administering surfactant with budesonide to infants under 30 weeks of age significantly reduced the number of deaths compared to using surfactant alone (5 vs. 17). Similar positive effects were observed for the occurrence of Pulmonary Hemorrhage, the need for a second dose of surfactant, oxygen index, mean blood pressure and mean arterial pressure (MAP) in infants under 34 weeks of age compared to more than 34 weeks (p < 0.05). CONCLUSION: These findings suggest that the combination therapy of surfactant and budesonide may be beneficial, particularly in preterm infants with less than 34 weeks gestational age and 1500 birth weight. However, further studies with larger sample sizes and longer follow-up periods are needed to confirm these results and assess long-term outcomes. TRIAL REGISTRATION: The study was registered at the Iranian Registry of Clinical Trials website under the code IRCT20201222049802N1. https://en.irct.ir/user/trial/48117/view . REGISTRATION DATE: 28/02/2021. PUBLIC REPOSITORY: DATA SET: This research data set link is displayed on the Zanjan-Iran Medical Sciences website: https://repository.zums.ac.ir/cgi/users/login? target=https%3 A%2 F/repository.zums.ac.ir/id/eprint .

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)

[Clinical value of the implication of extracorporeal carbon dioxide removal in patients with acute respiratory distress syndrome].

Extracorporeal carbon dioxide removal (ECCO2R) is a respiratory support technique based on extra-pulmonary gas exchange, which can effectively remove carbon dioxide generated in-vivo, reducing the requirements of respiratory support from mechanical ventilation. With improvements in extracorporeal life support technologies and increasing clinical experience, ECCO2R has potential value in clinical application with acute respiratory distress syndrome (ARDS). This review article discusses the principles of ECCO2R, its relevant indications for ARDS, clinical evidence, existing issues, and future directions, aiming to provide more references for the application in ARDS.

[The mechanical ventilation guided by electrical impedance tomography in acute respiratory distress syndrome].

Acute respiratory distress syndrome (ARDS) is a common and critical clinical condition characterized by diffuse damage to the lung interstitium, alveoli, and increased permeability of pulmonary blood vessels. CT can be used to assess the imaging features, severity, and prediction of ARDS, but it requires patient transportation to the CT room and is only a static examination. Electrical impedance tomography (EIT) is an increasingly widely used monitoring tool in clinical applications in recent years. It enables continuous real-time assessment of lung ventilation distribution at the bedside and has high clinical value in optimizing mechanical ventilation parameters for critically ill patients. This article introduces the basic principles of EIT and how to better utilize EIT technology to guide mechanical ventilation treatment for ARDS patients.

Opioid versus Benzodiazepine-based Sedation for Mechanically Ventilated Patients in the Internal Medicine Ward.

BACKGROUND: Opioid-base sedation is considered the first line choice in ventilated patients in intensive care units (ICU). Few studies have examined sedation in ventilated patients outside the ICU. A pilot program was initiated in the internal medicine ward A at Meir Hospital in Kfar Saba, Israel. A new sedation protocol was implemented for opioid-based versus benzodiazepine-based sedation in ventilated patients. OBJECTIVES: To compare the rates and intensity of delirium between patients who received opioid-based sedation vs. benzodiazepine-based sedation. To compare parameters related to morbidity and mortality. METHODS: We conducted a retrospective before-after intervention study based on data collection. Patients who were admitted to the internal medicine ward A from January 2020 to January 2021 and required sedation and ventilation were included. Demographic data, medical history data, admission data, Richmond Agitation and Sedation Scale scores, hemodynamic parameters, reports of falls and self-harm, and data regarding unplanned extubation were collected, as well as the need for additional sedative drugs. RESULTS: Chronic hypertension was more common in the opioid group. Delirium intensity tended to be higher in the benzodiazepine group. The number of ventilation days was significantly higher in the benzodiazepine group, as was the number of times adjuvant sedation was required. CONCLUSIONS: Opioid-based sedation outside the ICU was associated with shorter ventilation days, tendency toward lower intensity of delirium, and reduction in requirement of adjuvant sedative drugs compared to benzodiazepine-based sedation. Further studies are required to confirm the findings.

Quantifiable identification of flow-limited ventilator dyssynchrony with the deformed lung ventilator model.

BACKGROUND: Ventilator dyssynchrony (VD) can worsen lung injury and is challenging to detect and quantify due to the complex variability in the dyssynchronous breaths. While machine learning (ML) approaches are useful for automating VD detection from the ventilator waveform data, scalable severity quantification and its association with pathogenesis and ventilator mechanics remain challenging. OBJECTIVE: We develop a systematic framework to quantify pathophysiological features observed in ventilator waveform signals such that they can be used to create feature-based severity stratification of VD breaths. METHODS: A mathematical model was developed to represent the pressure and volume waveforms of individual breaths in a feature-based parametric form. Model estimates of respiratory effort strength were used to assess the severity of flow-limited (FL)-VD breaths compared to normal breaths. A total of 93,007 breath waveforms from 13 patients were analyzed. RESULTS: A novel model-defined continuous severity marker was developed and used to estimate breath phenotypes of FL-VD breaths. The phenotypes had a predictive accuracy of over 97% with respect to the previously developed ML-VD identification algorithm. To understand the incidence of FL-VD breaths and their association with the patient state, these phenotypes were further successfully correlated with ventilator-measured parameters and electronic health records. CONCLUSION: This work provides a computational pipeline to identify and quantify the severity of FL-VD breaths and paves the way for a large-scale study of VD causes and effects. This approach has direct application to clinical practice and in meaningful knowledge extraction from the ventilator waveform data.

Body Positions Alter Hemodynamics and Respiration in Healthy Adults: A Systematic Review and Meta-Analysis.

Objective Different body positions can exert both positive and negative physiological effects on hemodynamics and respiration. This study aims to conduct a literature review and examine hemodynamic and respiratory alterations to different body positions.Methods The study protocol was registered with the International Prospective Registry of Systematic Reviews (register no. CRD42021291464). Two independent reviewers evaluated the methodological quality of all included studies using the Down and Black checklist, while the quality of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluations approach. The overall effects of different body positions were reported from random effects meta-analysis.Results Three studies with low risk of bias and ten with high risk of bias met the eligibility criteria. The supine resulted in the highest cardiac output compared to the 70 deg head-up tilt, sitting, and standing positions (very low- to moderate-quality evidences) and the lowest systemic vascular resistance compared to the 70 deg head-up tilt and standing positions (moderate-quality evidence). Additionally, the supine was associated with the highest total respiratory resistance compared to the 70 deg head-up tilt, left lateral, and standing positions (very low-to moderate-quality evidence) and higher alveolar ventilation than the prone (low-quality evidence).Conclusions The supine position has the most positive association with hemodynamic variables, resulting in the highest cardiac output and the lowest systemic vascular resistance. The upright positions (70 deg head-up tilt and standing positions) has the most positive association with the respiratory variables, resulting in the lowest total respiratory resistance.

The intervention of artificial intelligence to improve the weaning outcomes of patients with mechanical ventilation: Practical applications in the medical intensive care unit and the COVID-19 intensive care unit: A retrospective study.

Patients admitted to intensive care units (ICU) and receiving mechanical ventilation (MV) may experience ventilator-associated adverse events and have prolonged ICU length of stay (LOS). We conducted a survey on adult patients in the medical ICU requiring MV. Utilizing big data and artificial intelligence (AI)/machine learning, we developed a predictive model to determine the optimal timing for weaning success, defined as no reintubation within 48 hours. An interdisciplinary team integrated AI into our MV weaning protocol. The study was divided into 2 parts. The first part compared outcomes before AI (May 1 to Nov 30, 2019) and after AI (May 1 to Nov 30, 2020) implementation in the medical ICU. The second part took place during the COVID-19 pandemic, where patients were divided into control (without AI assistance) and intervention (with AI assistance) groups from Aug 1, 2022, to Apr 30, 2023, and we compared their short-term outcomes. In the first part of the study, the intervention group (with AI, n = 1107) showed a shorter mean MV time (144.3 hours vs 158.7 hours, P = .077), ICU LOS (8.3 days vs 8.8 days, P = .194), and hospital LOS (22.2 days vs 25.7 days, P = .001) compared to the pre-intervention group (without AI, n = 1298). In the second part of the study, the intervention group (with AI, n = 88) exhibited a shorter mean MV time (244.2 hours vs 426.0 hours, P = .011), ICU LOS (11.0 days vs 18.7 days, P = .001), and hospital LOS (23.5 days vs 40.4 days, P < .001) compared to the control group (without AI, n = 43). The integration of AI into the weaning protocol led to improvements in the quality and outcomes of MV patients.

Pressure Support Ventilation Versus T-piece as Spontaneous Breathing Trials for Extubation of Patients with Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Weaning patients with COPD from mechanical ventilation (MV) presents a challenge, as literature on this topic is limited. This study compares PSV and T-piece during spontaneous breathing trials (SBT) in this specific population. METHODS: A search of PubMed, EMBASE, and Cochrane in September 2023 yielded four randomized controlled trials (RCTs) encompassing 560 patients. Among these, 287 (51%) used T-piece during SBTs. RESULTS: The PSV group demonstrated a significant improvement in the successful extubation rate compared to the T-piece (risk ratio [RR] 1.14; 95% confidence interval [CI] 1.03-1.26; p = 0.02). Otherwise, there was no statistically significant difference in the reintubation (RR 1.07; 95% CI 0.79-1.45; p = 0.67) or the ICU mortality rates (RR 0.99; 95% CI 0.63-1.55; p = 0.95). CONCLUSION: Although PSV in SBTs exhibits superior extubation success, consistent weaning protocols warrant further exploration through additional studies.

Machine learning algorithm for ventilator mode selection, pressure and volume control.

Mechanical ventilation techniques are vital for preserving individuals with a serious condition lives in the prolonged hospitalization unit. Nevertheless, an imbalance amid the hospitalized people demands and the respiratory structure could cause to inconsistencies in the patient's inhalation. To tackle this problem, this study presents an Iterative Learning PID Controller (ILC-PID), a unique current cycle feedback type controller that helps in gaining the correct pressure and volume. The paper also offers a clear and complete examination of the primarily efficient neural approach for generating optimal inhalation strategies. Moreover, machine learning-based classifiers are used to evaluate the precision and performance of the ILC-PID controller. These classifiers able to forecast and choose the perfect type for various inhalation modes, eliminating the likelihood that patients will require mechanical ventilation. In pressure control, the suggested accurate neural categorization exhibited an average accuracy rate of 88.2% in continuous positive airway pressure (CPAP) mode and 91.7% in proportional assist ventilation (PAV) mode while comparing with the other classifiers like ensemble classifier has reduced accuracy rate of 69.5% in CPAP mode and also 71.7% in PAV mode. An average accuracy of 78.9% rate in other classifiers compared to neutral network in CPAP. The neural model had an typical range of 81.6% in CPAP mode and 84.59% in PAV mode for 20 cm H2O of volume created by the neural network classifier in the volume investigation. Compared to the other classifiers, an average of 72.17% was in CPAP mode, and 77.83% was in PAV mode in volume control. Different approaches, such as decision trees, optimizable Bayes trees, naive Bayes trees, nearest neighbour trees, and an ensemble of trees, were also evaluated regarding the accuracy by confusion matrix concept, training duration, specificity, sensitivity, and F1 score.

Effect of Ventilator Settings on Mechanical Power During Simulated Mechanical Ventilation of Patients With ARDS.

BACKGROUND: In recent years, mechanical power (MP) has emerged as an important concept that can significantly impact outcomes from mechanical ventilation. Several individual components of ventilatory support such as tidal volume (VT), breathing frequency, and PEEP have been shown to contribute to the extent of MP delivered from a mechanical ventilator to patients in respiratory distress/failure. The aim of this study was to identify which common individual setting of mechanical ventilation is more efficient in maintaining safe and protective levels of MP using different modes of ventilation in simulated subjects with ARDS. METHODS: We used an interactive mathematical model of ventilator output during volume control ventilation (VCV) with either constant inspiratory flow (VCV-CF) or descending ramp inspiratory flow, as well as pressure control ventilation (PCV). MP values were determined for simulated subjects with mild, moderate, and severe ARDS; and whenever MP > 17 J/min, VT, breathing frequency, or PEEP was manipulated independently to bring back MP to ≤ 17 J/min. Finally, the optimum VT-breathing frequency combinations for MP = 17 J/min were determined with all 3 modes of ventilation. RESULTS: VCV-CF always resulted in the lowest MPs while PCV resulted in highest MPs. Reductions in VT were the most efficient for maintaining safer and protective MP. At targeted MPs of 17 J/min and maximized minute ventilation, the optimum VT-breathing frequency combinations were 250-350 mL for VT and 32-35 breaths/min for breathing frequency in mild ARDS, 200-350 mL for VT and 34-40 breaths/min for breathing frequency in moderate ARDS, and 200-300 mL for VT and 37-45 breaths/min for breathing frequency for severe ARDS. CONCLUSIONS: VCV-CF resulted in the lowest MP. VT was the most efficient for maintaining safe and protective MP in a mathematical simulation of subjects with ARDS. In the context of maintaining low and safe MPs, ventilatory strategies with lower-than-normal VT and higher-than-normal breathing frequency will need to be implemented in patients with ARDS.

Impacto de la edad, las comorbilidades y las complicaciones en pacientes con COVID-19 con síndrome de dificultad respiratoria aguda en la ventilación mecánica invasiva. Estudio multicéntrico observacional / Impact of Age, Comorbidities and Complications in COVID-19 Patients with Acute Respiratory Distress Syndrome on Invasive Mechanical Ventilation. An Observational Multicenter Study

Objetivos: Millones de pacientes con COVID-19 fueron internados en terapia intensiva en el mundo, la mitad desarrollaron síndrome de dificultad respiratoria aguda (SDRA) y recibieron ventilación mecánica invasiva (VMI), con una mortalidad del 50%. Analiza-mos cómo edad, comorbilidades y complicaciones, en pacientes con COVID-19 y SDRA que recibieron VMI, se asociaron con el riesgo de morir durante su hospitalización.Métodos: Estudio de cohorte observacional, retrospectivo y multicéntrico realizado en 5 hospitales (tres privados y dos públicos universitarios) de Argentina y Chile, durante el segundo semestre de 2020.Se incluyeron pacientes >18 años con infección por SARS-CoV-2 confirmada RT-PCR, que desarrollaron SDRA y fueron asistidos con VMI durante >48 horas, durante el se-gundo semestre de 2020. Se analizaron los antecedentes, las comorbilidades más fre-cuentes (obesidad, diabetes e hipertensión), y las complicaciones shock, insuficiencia renal aguda (IRA) y neumonía asociada a la ventilación mecánica (NAV), por un lado, y las alteraciones de parámetros clínicos y de laboratorio registrados.Resultados: El 69% era varón. La incidencia de comorbilidades difirió para los diferentes grupos de edad. La mortalidad aumentó significativamente con la edad (p<0,00001). Las comorbilidades, hipertensión y diabetes, y las complicaciones de IRA y shock se asociaron significativamente con la mortalidad. En el análisis multivariado, sólo la edad mayor de 60 años, la IRA y el shock permanecieron asociados con la mortalidad. Conclusiones: El SDRA en COVID-19 es más común entre los mayores. Solo la edad >60 años, el shock y la IRA se asociaron a la mortalidad en el análisis multivariado.

Objectives: Millions of patients with COVID-19 were admitted to intensive care world-wide, half developed acute respiratory distress syndrome (ARDS) and received invasive mechanical ventilation (IMV), with a mortality of 50%. We analyzed how age, comor-bidities and complications in patients with COVID-19 and ARDS who received IMV were associated with the risk of dying during their hospitalization.Methods: Observational, retrospective and multicenter cohort study carried out in 5 hospitals (three private and two public university hospitals) in Argentina and Chile, during the second half of 2020.Patients >18 years of age with SARS-CoV-2 infection confirmed by RT-PCR, who devel-oped ARDS and were assisted with IMV for >48 hours, during the second half of 2020, were included. History, the most frequent comorbidities (obesity, diabetes and hyper-tension) and the complications of shock, acute renal failure (AKI) and pneumonia as-sociated with mechanical ventilation (VAP), on the one hand, and the alterations of re-corded clinical and laboratory parameters, were analyzed.Results: 69% were men. The incidence of comorbidities differed for different age groups. Mortality increased significantly with age (p<0.00001). Comorbidities, hyper-tension and diabetes, and complications of ARF and shock were significantly associat-ed with mortality. In the multivariate analysis, only age over 60 years, ARF and shock remained associated with mortality.Conclusions: ARDS in COVID-19 is more common among the elderly. Only age >60 years, shock and ARF were associated with mortality in the multivariate analysis

Descripción de las intervenciones broncoscópicas en estenosis traqueales posterior a infección por COVID-19 / Description of Bronchoscopic Interventions in Post-COVID Tracheal Stenosis

Introducción: La infección por SARS-CoV-2 puede presentar síndrome de distrés res-piratorio agudo con requerimiento de ventilación mecánica prolongada y retraso en la realización de traqueostomía. Esto trae como consecuencia un incremento en casos de estenosis traqueal y la necesidad de métodos menos invasivos para su abordaje. Métodos: Estudio descriptivo de corte transversal, desde marzo 2020 hasta diciem-bre 2021 en el Hospital Universitario Nacional de Colombia, en adultos con estenosis traqueal postintubación asociado SARS-CoV-2. Se realizó análisis univariado entre los grupos con infección o no por SARS-CoV-2 como control, y reintervención, grado de estenosis, uso de inyección intramucosa con dexametasona intratraqueal o múltiples estenosis como desenlaces de importancia. Se usó test exacto de Fisher, t Student y Man-Whitney según la naturaleza de variables. Se consideró p estadísticamente significativo menor a 0.05.Resultados: Se identificaron 26 pacientes, 20 tenían COVID-19 y 6 no. Se encontraron diferencias en edad (p=0,002), epilepsia (p=0,007) y estenosis múltiple (p= 0,04). En 85% de los casos se utilizó láser blue más dilatación con balón pulmonar, en 35% inyección intramucosa con dexametasona intratraqueal y reintervención en 35%, sin diferencias significativas entre grupos. Conclusiones: Se observó un incremento tres veces mayor de pacientes con estenosis múltiple en el grupo de infección por COVID-19, así mismo se encontró que el método más utilizado en este grupo para la recanalización fue el uso de láser blue más dilatación con balón pulmonar y la innovación en el uso de inyección intramucosa.

Introduction: SARS-CoV-2 infection can lead to acute respiratory distress syndrome with a prolonged need for mechanical ventilation and delayed tracheostomy, resulting in an increase in cases of tracheal stenosis and the necessity for less invasive approaches.Methods: A descriptive cross-sectional study was conducted from March 2020 to December 2021 at the Hospital Universitario Nacional de Colombia, focusing on adults with post-intubation tracheal stenosis associated with SARS-CoV-2. Univariate analysis was performed between groups with or without SARS-CoV-2 infection as a control, considering reintervention, degree of stenosis, use of intratracheal steroids, or multiple stenoses as important outcomes. Fisher's exact test, Student's t-test, and Mann-Whit-ney test were employed based on the nature of variables. A p-value less than 0.05 was considered statistically significant.Results: A total of 26 patients were included, with 20 having COVID-19 and 6 without. Significant differences were found in age (p=0.002), epilepsy (p=0.007), and multiple stenosis (p=0.04). In 85% of cases, laser blue plus balloon pulmonary dilation was used, intratracheal dexamethasone in 35%, and reintervention in 35%, with no significant differences between groups.Conclusions: A threefold increase in subglottic stenosis was observed during the SARS-CoV-2 pandemic, with more instances of multiple stenosis and predominantly the use of laser blue plus balloon pulmonary dilation as a successful recanalization technique. There was a higher use of intratracheal dexamethasone in this group compared to oth-er pathologies causing tracheal stenosis.

[Effect of early pulmonary rehabilitation training on the prognosis of patients with acute respiratory distress syndrome after weaning of invasive mechanical ventilation in the intensive care unit].

OBJECTIVE: To investigate the effect of early pulmonary rehabilitation (PR) training on the improvement of respiratory function in patients with acute respiratory distress syndrome (ARDS) after weaning of invasive mechanical ventilation in the intensive care unit (ICU). METHODS: The retrospective cohort research method was used. The clinical information of adult patients with ARDS receiving invasive mechanical ventilation admitted to the ICU of Qingdao Municipal Hospital from January 2019 to March 2023 was collected. The patients were divided into a control group and an observation group according to off-line training program. The control group received traditional training after weaning, and the observation group received the early PR training after weaning. Other treatments and nursing were implemented according to the routine of the ICU. The scores of the short physical performance battery (SPPB) on day 3-day 6 of the weaning training, respiratory muscle strength, level of interleukin-6 (IL-6), number of aspirations of sputum after weaning, length of stay after weaning, rehospitalization rate within 6 months after discharge, and pulmonary function indicators at discharge and 3 months after discharge [peak expiratory flow (PEF), forced expiratory volume in one second/forced vital capacity ratio (FEV1/FVC), and vital capacity (VC)] of the two groups of patients were compared. The Kaplan-Meier survival curve was drawn to analyze the cumulative survival rate of patients 6 months after discharge. RESULTS: A total of 50 of which 25 cases received the traditional training after weaning, 25 cases received the early PR training after weaning. There was no significant difference in gender, age, acute physiology and chronic health evaluation II (APACHE II), oxygenation index upon admission, etiological diagnosis of ARDS upon admission, time of invasive ventilation, mode of invasive mechanical ventilation, pulmonary function indicators at discharge, and other baseline data of the two groups. The SPPB questionnaire scores and respiratory muscle strength in both groups were increased gradually with the extended offline training time, the serum level of IL-6 in both groups were descend gradually with the extended offline training time, especially in the observation group [SPPB questionnaire score in the observation group were 7.81±0.33, 8.72±0.53, 9.44±0.31, 10.57±0.50, while in the control group were 7.74±0.68, 8.73±0.37, 8.72±0.40, 9.33±0.26, effect of time: F = 192.532, P = 0.000, effect of intervention: F = 88.561, P = 0.000, interaction effect between intervention and time: F = 24.724, P = 0.000; respiratory muscle strength (mmHg, 1 mmHg≈0.133 kPa) in the observation group were 123.20±24.84, 137.00±26.47, 149.00±24.70, 155.40±29.37, while in the control group were 129.00±20.34, 126.00±24.01, 132.20±25.15, 138.60±36.67, effect of time: F = 5.926, P = 0.001, effect of intervention: F = 5.248, P = 0.031, interaction effect between intervention and time: F = 3.033, P = 0.043; serum level of IL-6 in the observation group were 80.05±6.81, 74.76±9.33, 63.66±10.19, 56.95±4.72, while in the control group were 80.18±7.21, 77.23±9.78, 71.79±10.40, 66.51±6.49, effect of time: F = 53.485, P = 0.000, effect of intervention: F = 22.942, P = 0.000, interaction effect between intervention and time: F = 3.266, P = 0.026]. Compared with the control group, the number of aspirations of sputum after weaning of patients in the observation group significantly decreased (number: 22.46±1.76 vs. 27.31±0.90), the length of ICU stay after weaning significantly became shorter (days: 6.93±0.95 vs. 8.52±2.21), and the rehospitalization rate within 6 months after discharge significantly decreased [20.00% (5/25) vs. 48.00% (12/25)]. There were significant differences. The pulmonary function indicators 3 months after discharge of two groups of patients significantly increased compared with those at discharge and those of the observation group were significantly higher than those of the control group [PEF (L/min): 430.20±95.18 vs. 370.00±108.44, FEV1/FVC ratio: 0.88±0.04 vs. 0.82±0.05, VC (L): 3.22±0.72 vs. 2.74±0.37, all P < 0.05]. The Kaplan-Meier survival curve showed that the cumulative survival rate of patients 6 months after discharge of patients in the observation group was significantly higher than that of patients in the control group [76.9% vs. 45.5%, hazard ratio (HR) = 0.344, P = 0.017]. CONCLUSIONS: Early PR training can significantly improve the respiratory function of patients with ARDS after weaning of invasive mechanical ventilation. Continuous active respiratory training after discharge can improve the respiratory function of patients and effectively decrease mortality.

Testing pulmonary physiology in ventilated non-human primates.

BACKGROUND: Animal models of respiratory viral infections are essential for investigating disease pathogenesis and the efficacy of antivirals and vaccine candidates. A major limitation in the research of respiratory diseases in animal models is correlating clinically relevant changes in pulmonary physiology with cellular and molecular mechanistic studies. Few animal models have captured and correlated physiologic changes in lung function and immune response within same experiment, which is critical given the heterogeneous nature of lung disease due to viral infections. In ventilated human patients, pulmonary physiology testing can be used to not only capture oxygenation, ventilation, but also pulmonary mechanics to yield quantitative measures of lung function and scalar tracings of flow-volume and pressure-volume loops. Application of this protocol during mechanical ventilation in non-human (NHP) models would represent a major advance in respiratory viral disease research. METHODS: We have applied and optimized a human pulmonary physiology testing protocol to ventilated pigtail macaques (Macaca nemestrina) at baseline and 5 days after influenza A (IAV) viral inoculation. RESULTS: The NHPs manifested clinical disease with hypothermia and loss of body weight. Declines in lung function were striking with a 66%-81% decline in P/F ratio, a measure of oxygenation reflecting the ratio of partial pressure of oxygen in arterial blood (PaO2 ) to the fraction of inspiratory oxygen concentration (FiO2 ). There was also a 16%-45% decline in lung compliance. CONCLUSION: We describe a new approach to performing pulmonary physiology testing protocol in non-human primates to better capture quantitative correlates of respiratory disease and demonstrate protection by therapeutics and vaccines.