patients who fail weaning have impaired ability to convert neuromuscular activity into tidal ventilation, highlighting the eff ect of diaphragm weakness on weaning and extubation from mechanical ventilation. However, it is noteworthy that the insuffi cient cough strength greatly contributes to failed extubation in clinical practice as well, particularly in patients with acute cervical cord inju...

Dr KOULOURIS and co-workers [1] found that some patients with chronic obstructive pulmonary disease (COPD) and apparent expiratory flow-limitation during tidal breathing had increased expiratory flow during tidal breathing when negative pressure was applied to the airway. They concluded that flow could not have been limited during control tidal expirations. I thought that the shape of the flow-...

In normal subjects and patients with airway obstruction, flows during a forced vital capacity (FVC) manoeuvre are higher after a fast inspiration without an end-inspiratory pause (manoeuvre 1) as compared to a slow inspiration with an end-expiratory pause of approximately 5 s (manoeuvre 2). In this study, we investigated the influence of these manoeuvres on maximal expiratory volume-time and fl...

The present study was undertaken to gain further insight into the mechanisms responsible for the sustained active expiratory upper airway closure previously observed during high-permeability pulmonary edema in lambs. The experiments were conducted in nonsedated lambs, in which airflow and thyroarytenoid and inferior pharyngeal constrictor muscle electromyographic activity were recorded. We firs...

Current guidelines recommend measurement of pulmonary artery wedge pressure (PAWP) at end-expiration. However, this recommendation is not universally followed and may not be physiologically appropriate. We investigated the performance of end-expiratory PAWP in the evaluation of precapillary pulmonary hypertension patients. 329 spontaneously breathing patients undergoing right heart catheterisat...

The present study investigated how end-expiratory ribcage and abdominal volume regulation during exercise is related to the degree of dynamic chest wall hyperinflation in patients with different spirometric severity of chronic obstructive pulmonary disease (COPD) based on the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification. In total, 42 COPD patients and 11 age-matc...

Introduction: Expiratory upper airway obstruction during bag-mask ventilation is not well characterized. Methods: An audit was done to assess expiratory obstruction in 90 adult surgical patients undergoing bag-mask ventilation during the induction of general anaesthesia. Results: Clinicians experienced difficulty delivering gas to the lungs when the head was neutral in 52 of 90 patients (58%; i...

Our main aim was to determine an appropriate time for lung function measurements in infants, prior to environmental influences upon their respiratory tract. Tidal flow-volume loops, respiratory system compliance (Crs) and resistance (Rrs) (single breath passive occlusion technique) were measured in 24 healthy, awake awake infants, at one hour and on the following four days of life to investigat...

Several types of respiratory reflex actions can be discerned according to the reactions of typical respiratory neurons in the efferent part of the central rhythmogenic structure. Whereas respiration runs closely parallel with inspiratory neuron activity the behaviour of expiratory neurons cannot be derived from the resulting reflex changes of respiration. So expiratory apnoea can be combined wi...

Mice have been widely used in immunologic and other research to study the influence of different diseases on the lungs. However, the respiratory mechanical properties of the mouse are not clear. This study extended the methodology of measuring respiratory mechanics of anesthetized rats and guinea pigs and applied it to the mouse. First, we performed static pressure-volume and maximal expiratory...