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A versatile hydraulically operated respiratory servo system for ventilation and lung function testing.

M Meyer·H Slama
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Abstract

A description is given of the design and performance of a microcomputer-controlled respiratory servo system that incorporates the characteristics of a mechanical ventilator and also allows the performance of a multitude of test procedures required for assessment of pulmonary function in paralyzed animals. The device consists of a hydraulically operated cylinder-piston assembly and solenoid valves that direct inspiratory and expiratory gas flow and also enable switching to different test gas sources. The system operates as a volume-flow-preset ventilator but may be switched to other operational cycling modes. Gas flow rates may be constant or variable. The system operates as an assister-controller and, combined with a gas analyzer, can function as a "demand" ventilator allowing for set-point control of end-tidal PCO2 and PO2. Complex breathing maneuvers for a variety of single- and multiple-breath lung function tests are automatically performed. Because of the flexibility in selection and timing of respiratory parameters, the system is particularly suitable for respiratory gas studies.

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Lung Volume MeasurementsMicrocomputersPositive-Pressure RespirationRespiration, ArtificialRespiratory Function TestsJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

M Meyer, H Slama. 1983. A versatile hydraulically operated respiratory servo system for ventilation and lung function testing.. https://doi.org/10.1152/jappl.1983.55.3.1023

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