Influences of assisted breathing and mechanical ventilator settings on tidal volume and alveolar pressures in acute respiratory distress syndrome: a bench study.

Objective: To evaluate the influences of respiratory muscle efforts and respiratory rate setting in the ventilator on tidal volume and alveolar distending pressures at end inspiration and expiration in volume-controlled ventilation and pressure-controlled ventilation modes in acute respiratory distress syndrome.

Methods: An active test lung (ASL 5000™) connected to five intensive care unit ventilators was used in a model of acute respiratory distress syndrome. Respiratory muscle efforts (muscle pressure) were configured in three different ways: no effort (muscle pressure: 0cmH2O); inspiratory efforts only (muscle pressure:-5cmH2O, neural inspiratory time of 0.

Acute effects of noninvasive ventilation on sleep physiology in patients with moderate to severe stable chronic obstructive pulmonary disease: a pilot study.

Objective/background: Changes in sleep architecture in patients with Chronic Obstructive Pulmonary Disease (COPD) can be explained by a combination of physiological changes in breathing during sleep, with impairment of respiratory mechanics and reduction of arterial oxygenation. This study aimed to evaluate the acute effects of noninvasive ventilation (NIV) - compared to spontaneous breathing - on sleep latency and stages, and on the occurrence of sleep-related respiratory events, nocturnal hypoxemia, and changes in heart rate (HR) in patients with moderate to severe stable COPD.

Patients/methods: Patients completed two polysomnography (PSG) studies: one during spontaneous breathing and one while receiving NIV in bilevel mode and with backup respiratory rate (RR.

Helping students to understand physiological aspects of regional distribution of ventilation in humans: a experience from the electrical impedance tomography.

Undergraduate biomedical students often have difficulties in understanding basic concepts of respiratory physiology, particularly respiratory mechanics. In this study, we report the use of electrical impedance tomography (EIT) to improve and consolidate the knowledge about physiological aspects of normal regional distribution of ventilation in humans. Initially, we assessed the previous knowledge of a group of medical students ( n = 39) about regional differences in lung ventilation.

Exercise Capacity Impairment Can Predict Postoperative Pulmonary Complications after Liver Transplantation.

Background: Postoperative respiratory complications (PRCs) are common after liver transplantation (LT) and contribute significantly to the related morbidity and mortality.

Objective: The aim of this paper was to determine the incidence of PRCs after LT and the value of simple exercise capacity measures as independent predictors of PRCs.

Methods: We conducted a prospective cohort study of consecutive adults submitted to LT at a University Hospital in Fortaleza Brazil from March 2013 to March 2015.

Assessment of regional lung ventilation by electrical impedance tomography in a patient with unilateral bronchial stenosis and a history of tuberculosis.

Bronchial stenosis can impair regional lung ventilation by causing abnormal, asymmetric airflow limitation. Electrical impedance tomography (EIT) is an imaging technique that allows the assessment of regional lung ventilation and therefore complements the functional assessment of the lungs. We report the case of a patient with left unilateral bronchial stenosis and a history of tuberculosis, in whom regional lung ventilation was assessed by EIT.