AIM To determine the ability of intrapulmonary percussive ventilation (IPV) to promote airway clearance in spontaneously breathing patients and those on mechanical ventilation. METHODS An artificial lung was used to simulate a spontaneously breathing patient (Group 1), and was then connected to a mechanical ventilator to simulate a patient on mechanical ventilation (Group 2). An 8.5 mm endotr...

BACKGROUND A novel double-lumen endotracheal tube, the Papworth BiVent tube, has been designed to allow the rapid passage of a blocker into either main bronchus, without fibreoptic endoscopic guidance. METHODS The feasibility of lung isolation and one-lung ventilation (OLV) in human cadavers is examined, along with displacement of the bronchus blocker during head and neck movement. RESULTS ...

CORRESPONDENCE THE LARYNGEAL MASK FOR INTRAOCULAR SURGERY Sir,—Ripart, Cohendy and Eledjam [1], in commenting upon the article by Lamb, James and Janicki [2], described two untoward incidents associated with the use of the laryngcal mask airway (LMA) for controlled ventilation during intraocular surgery. As a result, they have abandoned the technique. They have done so without relating the inci...

UNLABELLED As people spend most of their time in an indoor environment, it is important to predict indoor pollutant level in order to assess health risks. As particles are an important pollutant indoors, it is of great interest to study the airflow pattern and particle dispersion in buildings. This study uses large eddy simulation (LES) to predict three-dimensional and transient turbulent flows...

PURPOSE To quantify the dosimetric impact of four-dimensional computed tomography (4D-CT) pulmonary ventilation imaging-based functional treatment planning that avoids high-functional lung regions. METHODS AND MATERIALS 4D-CT ventilation images were created from 15 non-small-cell lung cancer patients using deformable image registration and quantitative analysis of the resultant displacement v...

An imaging-based computational framework for simulation of airflow in subject specific breathing human lungs is established. The three-dimensional (3D) airways of up to 9 generations and lobes are segmented and reconstructed from computed tomography (CT) images. Beyond the CT-resolved 3D airways, a volume filling method is applied to generate the one-dimensional (1D) conducting airway tree that...

Gill O2 uptake, CO2 excretion, ventilation and blood respiratory/acid­base variables were evaluated in control and softwater-acclimated trout (Oncorhynchus mykiss) to test the hypothesis that gill chloride cell (CC) proliferation, elicited by 2 weeks of softwater exposure, impairs the diffusion of respiratory gases across the gill. The proliferation of CCs in softwater fish was verified usi...

Most indoor airflows are mixed convection. In order to simulate mixed convection accurately and efficiently, this paper uses a two-layer turbulence model. The two-layer model combines a one-equation model for near wall flow together with the standard k-epsilon model for outer-wall flow. The model has been used to predict the mixed convection by displacement ventilation in an office. The compute...

Gas exchange in human lungs is established by several flow mechanisms. In the present study, the features of gas displacement in the distal bronchioles of a human lung are investigated by both numerical calculation and experimental observation with particle image velocimetry. The effect of respiration frequency is considered, such as high frequency oscillatory ventilation. By comparing the obta...