Respiratory devices pressure

The underpressure created in the respiratory tract is the driving force for the airflow through an inhalation device. The attainable underpressure and the rate of the airflow both depend on the total resistance in the airways and inhaler. The pressure drop achieved during inhalation is furthermore a function of the anatomy of the lungs, the effort made by the patient, pathological factors and the presence of exacerbations (e.g. in case of asthma). 

COMPASS investigators. In COMPASS, an implantable device that continuously monitors intra-cardiac pressures was shown to be safe and to improve care in patients with chronic heart failure [71]. Some simple measured parameters such as activity of the patient and heart rate and respiratory rate can be plotted over time to determine the patient s level of activity and provide insight into their functional status. 

How should hospitals increase their capacity to provide mechanical ventilation for a surge of patients with acute respiratory failure during a mass casualty event or influenza pandemic Rubinson and colleagues address this issue in a recently published article (Rubinson, Branson, Pesik, Talmor, 2006). Their report is based on an evaluation and assessment of a wide range of positive pressure ventilation (PPV) equipment, with the goal of determining the suitability of each device for mass casualty care. The article provides information useful for determining which types of PPV equipment would be the best choice for hospitals in need of a serviceable alternative to full feature ventilators, which will be in short supply and are too expensive for hospitals to stockpile. 

Most inhalation devices deliver approximately 10% of the administered dose to the lower respiratory tract. A number of devices have been developed to increase lung delivery, and delivery of up to 21% has been reported with a pressurized metered-dose inhaler. Despite these advances, drug delivery via the lung is still inefficient. 

Metered dose inhaler has been the most popular aerosol delivery device for the treatment of respiratory diseases, which is attributable to its portability and simple operation. Although seemingly easy to use, the MDI is a sophisticated device in design. The drug(s) are suspended or dissolved in a liquefied propellant system, which may also contain excipients such as cosolvents or surfactants. The formulation is kept pressurized in a small canister, sealed with a metering valve. Upon actuation through an actuator, the valve opens and the metered dose is dispensed as an aerosol spray from the expansion and vaporization of the propellant under ambient pressure. The inhalers may be used alone or with spacer devices, the electrostatic issues of which are considered in a later section. The present discussion focuses on the inherent charging of particles produced from MDIs. 

An oxygen enrichment device is needed for people with impaired respiratory systems. To design such a device, it is necessary to compute the work needed to produce a stream that contains 50 mol % of oxygen. from air (21 mol % oxygen) at 300 K and I bar. If the exit streams are at the same temperature and pressure as the inlet air, and half of the oxygen in the air is recovered in the enriched oxygen stream, what is the minimum amount of work required to operate whatever device is developed for this process ... 

Wearable technology consists of wearable electronics, a term that mainly includes simple and more complex electronic devices and their embedding within textile structures. A good example of the popularity of the research subject is the current Qualcomm Tricorder X-Prize competition for the best portable, wireless device that monitors and diagnoses health conditions (XPRIZE, 2014). Undoubtedly, as the aim is that the device monitors such elements as blood pressure, respiratory rate, and temperature, some of the sensors of the device will come in the form of textile-embedded electronics. 

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