[Invasive mechanical ventilation in COPD and asthma]

Factors associated with prolonged mechanical ventilation in children with pulmonary failure: Cohort study from the LARed Network registry

OBJECTIVES

To identify factors associated with prolonged mechanical ventilation (pMV) in pediatric patients in pediatric intensive care units (PICUs).

DESIGN

Secondary analysis of a prospective cohort.

SETTING

PICUs in centers that are part of the LARed Network between April 2017 and January 2022.

PARTICIPANTS

Pediatric patients on mechanical ventilation (IMV) due to respiratory causes. We defined IMV time greater than the 75th percentile of the global cohort.

INTERVENTIONS

None.

MAIN VARIABLES OF INTEREST

Demographic data, diagnoses, severity scores, therapies, complications, length of stay, morbidity, and mortality.

RESULTS

1698 children with MV of 8±7 days were included, and pIMV was defined as 9 days. Factors related to admission were age under 6 months (OR 1.61, 95% CI 1.17-2.22), bronchopulmonary dysplasia (OR 3.71, 95% CI 1.87-7.36), and fungal infections (OR 6.66, 95% CI 1.87-23.74), while patients with asthma had a lower risk of pIMV (OR 0.30, 95% CI 0.12-0.78). Regarding evolution and length of stay in the PICU, it was related to ventilation-associated pneumonia (OR 4.27, 95% CI 1.79-10.20), need for tracheostomy (OR 2.91, 95% CI 1.89-4.48), transfusions (OR 2.94, 95% CI 2.18-3.96), neuromuscular blockade (OR 2.08, 95% CI 1.48-2.93), high-frequency ventilation (OR 2.91, 95% CI 1.89-4.48), and longer PICU stay (OR 1.13, 95% CI 1.10-1.16). In addition, mean airway pressure greater than 13cmH2O was associated with pIMV (OR 1.57, 95% CI 1.12-2.21).

CONCLUSIONS

Factors related to IMV duration greater than 9 days in pediatric patients in PICUs were identified in terms of admission, evolution, and length of stay.

Diaphragm Dysfunction and Rehabilitation Strategy in Patients With Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) affects the whole body and causes many extrapulmonary adverse effects, amongst which diaphragm dysfunction is one of the prominent manifestations. Diaphragm dysfunction in patients with COPD is manifested as structural changes, such as diaphragm atrophy, single-fibre dysfunction, sarcomere injury and fibre type transformation, and functional changes such as muscle strength decline, endurance change, diaphragm fatigue, decreased diaphragm mobility, etc. Diaphragm dysfunction directly affects the respiratory efficiency of patients and is one of the important pathological mechanisms leading to progressive exacerbation of COPD and respiratory failure, which is closely related to disease mortality. At present, the possible mechanisms of diaphragm dysfunction in patients with COPD include systemic inflammation, oxidative stress, hyperinflation, chronic hypoxia and malnutrition. However, the specific mechanism of diaphragm dysfunction in COPD is still unclear, which, to some extent, increases the difficulty of treatment and rehabilitation. Therefore, on the basis of the review of changes in the structure and function of COPD diaphragm, the potential mechanism of diaphragm dysfunction in COPD was discussed, the current effective rehabilitation methods were also summarised in this paper. In order to provide direction reference and new ideas for the mechanism research and rehabilitation treatment of diaphragm dysfunction in COPD.

Negative results for ketamine use in severe acute bronchospasm: a randomised controlled trial

BACKGROUND

Ketamine has bronchodilation properties. The aim of the single-centre, evaluator-blinded, randomised clinical trial study was to evaluate whether continuous infusion of ketamine is associated with improvement in respiratory mechanics correlated with bronchospasm relief, as compared with continuous infusion of fentanyl.

METHODS

Adult patients submitted to invasive mechanical ventilation were included if they had an acute severe bronchospasm, due to status asthmaticus or COPD exacerbation. They were randomised to ketamine or a standard IV analgesia with fentanyl, both in bolus and continuous infusion. Measurements of respiratory mechanics (airway resistance - Rsmax, dynamic compliance - Cdyn and intrinsic PEEP - PEEPi) both at baseline and 3 and 24 h after randomisation were performed. The main outcome of this study was to evaluate the improvement of Rsmax in 3 h of continuous infusion of the study drugs.

RESULTS

Ketamine use was not associated with greater reduction in Rsmax when compared with fentanyl, either after 3 h (0 cm H2O L-1 s-1 ± 6 vs. -3 cm H2O L-1 s-1 ± 7.7, respectively; P = 0.16) or after 24 h (-3 cm H2O L-1 s-1 ± 17 vs. -3.5 cm H2O L-1 s-1 ± 13.7, respectively; P = 0.73). Patients randomized to the ketamine group did not have better improvements in delta PEEPi as compared with fentanyl in 3 h (P = 0.77) or in 24 h (P = 0.72).

CONCLUSIONS

In this study, ketamine use was not associated with improvement in ventilatory variables associated with bronchospasm.

The optimum timing to wean invasive ventilation for patients with AECOPD or COPD with pulmonary infection

COPD is characterized by a progressive decline in lung function and mental and physical comorbidities. It is a significant burden worldwide due to its growing prevalence, comorbidities, and mortality. Complication by bronchial-pulmonary infection causes 50%-90% of acute exacerbations of COPD (AECOPD), which may lead to the aggregation of COPD symptoms and the development of acute respiratory failure. Non-invasive or invasive ventilation (IV) is usually implemented to treat acute respiratory failure. However, ventilatory support (mainly IV) should be discarded as soon as possible to prevent the onset of time-dependent complications. To withdraw IV, an optimum timing has to be selected based on weaning assessment and spontaneous breathing trial or replacement of IV by non-IV at pulmonary infection control window. The former method is more suitable for patients with AECOPD without significant bronchial-pulmonary infection while the latter method is more suitable for patients with AECOPD with acute significant bronchial-pulmonary infection.

Mechanical ventilation in patients with chronic obstructive pulmonary disease and bronchial asthma

Chronic obstructive pulmonary disease (COPD) and bronchial asthma often complicate the surgical patients, leading to post-operative morbidity and mortality. Many authors have tried to predict post-operative pulmonary complications but not specifically in COPD. The aim of this review is to provide recent evidence-based guidelines regarding predictors and ventilatory strategies for mechanical ventilation in COPD and bronchial asthma patients. Using Google search for indexing databases, a search for articles published was performed using various combinations of the following search terms: ‘Predictors’; ‘mechanical ventilation’; COPD’; ‘COPD’; ‘bronchial asthma’; ‘recent strategies’. Additional sources were also identified by exploring the primary reference list.

Brazilian recommendations of mechanical ventilation 2013. Part I

Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumonia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

Brazilian recommendations of mechanical ventilation 2013. Part I

Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

Effectiveness and safety of a protocolized mechanical ventilation and weaning strategy of COPD patients by respiratory therapists

INTRODUCTION

Prior researches have showed that weaning protocols may decrease the duration of mechanical ventilation. The effect of these protocols on chronic obstructive pulmonary disease (COPD) patients is unknown. The purpose of this study was to evaluate the impact of an extensive mechanical ventilation protocol including weaning applied by a respiratory therapist (RT) on the duration of mechanical ventilation and intensive care unit (ICU) stay in COPD patients.

MATERIALS AND METHODS

A novel mechanical ventilation protocol including weaning was developed and initiated for all intubated COPD patients by a respiratory therapist. Outcomes of patients treated using this protocol during a 6-month period were compared to those of patients treated by physicians without a protocol during the preceding 6 months.

RESULTS

A total of 170 patients were enrolled. Extubation success was significantly higher (98% vs. 78%, P=0.014) and median durations of weaning, mechanical ventilation and ICU stay compared with time to event analysis were significantly shorter in the protocol based group (2 vs. 26 hours, log rank P<0.001, 3.1 vs. 5 days, log rank P<0.001 and 6 vs. 12 days, log rank P<0.001, respectively). Patients who were successfully extubated and patients in the protocol based group were more likely to have shorter ventilation duration [HR: 1.87, 95% confidence intervals (CI): 1.13-3.08, P=0.015 and HR: 2.08, 95% CI: 1.40-3.10, P<0.001 respectively].

CONCLUSIONS

In our center, a protocolized mechanical ventilation and weaning strategy improved weaning success and shortened the total duration of mechanical ventilation and ICU stay in COPD patients requiring mechanical ventilation.