Build Rev 2Adding 100% oxygen to the air supply tubing
In most situations of emergency respiratory ventilation, whether invasive or non-invasive, it is desirable to be able to blend 100% oxygen with room air to facilitate respiratory gas exchange and oxygenation of a patient’s tissues. Although this capability was added to the prototype, none of the valves used in the prototype were oxygen cleaned; and we had not yet added O2 pressure regulation. With Rev2, we substituted oxygen cleaned solenoid valves (with much better service life rating); and used appropriate detergent cleaners on the check valves. We also added the Olsen oxygen pressure regulator to the parts list and an air “Bypass line” to better control FiO2. Pick up a medical low pressure gage that reads cm H2O or millibars to evaluate port pressure at the point of patient circuit attachment. Although it adds cost to the unit, it may be advisable to add an inline oxygen meter to the manifold supply line downstream of the blend location to measure FiO2 directly (e.g. may want to evaluate Model MO-200 Oxygen meter and inline sensor by Apogee Instruments, Inc., in Utah).
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