Patent attributes
In an example, a ventilator includes an outer container containing liquid, an inverted container submerged in the liquid to provide inverted container space between a closed top and an inner container liquid level; gas supply line to supply breathing gas to the inverted container space; and inhalation line having an inlet in the inverted container space to provide breathing gas to patient. The inverted container moves upward from a preset minimum elevation when the inverted container space reaches a hydrostatic delivery pressure and volume of the inverted container space increases. The inverted container stops moving upward and the gas supply line stops supplying when the inverted container reaches a preset maximum elevation. Based on a breath demand signal or preset timing, the inhalation line opens to permit flow of breathing gas to the patient at the hydrostatic delivery pressure, lowering the inverted container due to lost buoyancy resulting in sinkage.
