[abstract] USE OF DRAGER - OXYLOG VENTILATOR IN THE MULTIPLACE CHAMBER

Abstract

BACKGROUND: A low-cost ventilatory support for critical patients is an important according the conditions of every region and medical center. We tested, in the chamber, the OXYLOG ventilator, often used in Europe and Brazil for critical patients transportation (including aeromedical). METHODS: With a Standard Test Lung (Michingan-TTL) connected to the ventilator, with a typical endotracheal tube (#9), we checked the flow with a calibrated Wright respirometer and the tube pressure with a water column. Oxygen was delivered with a supply line pressure of 6 kg/cm2. We made the tests up to 3 atm abs. Temperature and humidity were continuously checked. The pressurization and depressurization was made using 0.2 atm steps. RESULTS: The protocol standard was to keep a tidal volume of 700 ml and a RF between 14-16 breaths/minute, with an airway pressure of 22 mbar, the TTL compliance in this conditions was 200 ml/cmH2O. The typical equipment response during compression was linear (see table): decrease of tidal volume and airway pressure followed by an increase in the frequency - in decompression was the opposite - we made a standard correction rule: Correct the minute volume to achieve the correct airway, correct the frequency control to set the proper frequency. CONCLUSION: With or w/o an exhaust valve (Scott) connected in expiratory circuit, a PEEP of 2-3 cm/H2O was noticed. With a flowmeter and a digital cronometer the corrections are easy and stable. It is mandatory to have an overpressure valve. A minimum restriction in expiratory flow made the airway pressure increase highly and quickly. Tidal volumes smaller than 300 ml/min could not be corrected appropriately.