THE EFFECT OF AEROSOL DRUG DELIVERY ON AIRWAY RESISTANCE THROUGH HEAT-MOISTURE EXCHANGERS (HMEs) By Matthew Hart Introduction: The use of heat moisture exchangers (HMEs) is becoming more popular with many institutions delivering aerosolized medications between the HME and the endotracheal tube of patients being mechanically ventilated. When HMEs become saturated resistance can increase which ca...

Lung function detection in mice is currently most accurately measured by invasive techniques, which are costly, labor intensive, and terminal. This limits their use for large-scale or longitudinal studies. Noninvasive assays are often used instead, but their accuracy for measuring lung function parameters such as resistance and elastance has been questioned in studies involving small numbers of...

bronchial asthma represents an increased airways responsiveness to vari¬ous stimulants, leading to reversible obstruction of expiratory flow and chronic inflammatory changes in airways wall. ketamine has been demonstrated to lower airway resistance and to increase lung compliance in the asthmatic patients. in several studies and case reports it has been used successfully in the management of st...

Introduction: Evaluation of upper airway space is a routine procedure in orthodontic diagnosis and treatment planning. Although limited insofar as they provide two dimensional images of three-dimensional structures, lateral cephalometric radiographs have been used routinely to assess airway space permeability. Cone-Beam Computed Tomography (CBCT) has contributed to orthodontics with information...

In an effort to determine which measure of airway dynamics was the most sensitive to airway obstruction, comparisons were made between a variety of tests. Twenty cigarette smokers were studied both before and immediately after smoking a cigarette. The maximum midexpiratory flow (FEV25-75) and the FEV1/FVC per cent were abnormal in the largest number of cases. Closing volume was abnormal in only...

Increasing lung volume improves upper airway airflow dynamics via passive mechanisms such as reducing upper airway extraluminal tissue pressures (ETP) and increasing longitudinal tension via tracheal displacement. We hypothesized a threshold lung volume for optimal mechanical effects on upper airway airflow dynamics. Seven supine, anesthetized, spontaneously breathing New Zealand White rabbits ...

In patients with severe chronic obstructive pulmonary disease (COPD), lung emptying may be affected by flow limitation. We tested the hypothesis that the airway compression leading to flow limitation can be counteracted by controlling the expiratory flow. The effects of an external resistor on lung emptying were studied in six patients with COPD, who were mechanically ventilated whilst sedated ...

In the airways and lungs, nitric oxide (NO) is produced by epithelial ciliated cells, type II alveolar cells, and neural fibers that innervate the airway smooth muscle cells (SMCs) (Ricciardolo et al., 2004). It has been suggested that the NO released by these cells decreases airway resistance and that NO, released by neural fibers, is a major nonadrenergic, noncholinergic neurotransmitter resp...

Tidal airway closure occurs when the closing volume exceeds the end-expiratory lung volume, and it is commonly observed in general anaesthesia, particularly in obese patients. Animal studies suggest that tidal airway closure causes injury to peripheral airways, characterized histologically by rupture of alveolar-airway attachments, denuded epithelium, disruption of airway smooth muscle and incr...