A digital syringe is used with conventional polymer disposable syringe construction to be practical in the medical environment. Errors associated with the larger volumes of the syringes (which exacerbate minor errors in plunger position) and the flexibility and dimensional variations of the polymer plungers are accommodated by direct measurement of the syringe plunger position rather than indirect measurement of motor position and inference of syringe plunger position. This direct measurement eliminates mechanical tolerances (“stack up”) in the motor, gear train, and lead screw on plunger movement, an effect exacerbated by flexibility of the plunger and changes in syringe resistance and medicament viscosity, for example, with different medicaments or when the syringe is refrigerated. The digital syringe may be combined with the motor unit to provide additional versatility.

In a first embodiment, a ventilator has a housing with a first fixed port and a rotatable shutter configured to cooperate with the housing to enclose an interior of the housing. The shutter has a first orifice at a first radial distance from its axis of rotation. A stationary plate abuts the shutter and includes a first stationary orifice configured to at least partially align with the first orifice of the shutter over a first rotational distance of the shutter. In this way, the first orifice and the first stationary orifice form a first variable port. The stationary plate may have a second stationary orifice and the shutter may have a second orifice configured to at least partially align with the second stationary orifice over a second rotational distance of the shutter.

Devices, systems and methods for controlling, regulating, altering, transforming or otherwise modulating the delivery of a substance to a delivery site. The devices, systems and methods optimize the delivery of the substance to an intended site, such as a vessel, vascular bed, organ and/or other corporeal structures, while reducing inadvertent introduction or reflux substance to other vessels, vascular beds, organs, and/or other structures, including systemic introduction.

Systems and methods for monitoring for an occlusion in an aspiration line during an ophthalmic surgical procedure. An ophthalmic surgical system may include a first aspiration pump located in a handpiece, a second aspiration pump located away from the handpiece such as in a console, and a pressure sensor located between the first aspiration pump and the second aspiration pump. The pressure sensor is adapted to monitor for an occlusion in the aspiration line upstream of the first aspiration pump. The second aspiration pump may be operated at the same flow rate as the first aspiration pump and/or to maintain a constant pressure between the second aspiration pump and the first aspiration pump. Systems and methods as disclosed allow for a handpiece pump located close to the working tip while providing reliable occlusion detection with a pressure sensor located away from the handpiece.

An oxygen concentrator 100 apparatus and a method thereof implement operations control to efficiently release oxygen enriched gas to reduce potential waste. The control methodology may include generating a profile such as a minimum inhalation flow profile of the user. The profile may be based on a size parameter of the user. The method may determine one or more control parameters characterizing a bolus of oxygen enriched gas based on the generated flow profile. The control methodology may then generate a bolus release control signal, such as for a supply valve, according to the determined one or more control parameters. The oxygen concentrator may then, with the control signal, release and deliver a bolus of oxygen enriched gas for a user such as for reducing waste.

A system for delivering a medicinal fluid to a patient includes a variable volume pressure delivery chamber, a variable volume medication chamber, an optional medication reservoir, a movable delivery element, a fixed reference volume chamber, a pressure source, and a control sub-system. The variable volume pressure delivery chamber is configured to store pressure controllably. The variable volume medication chamber is fluidically isolated from the pressure delivery chamber and is configured to store medicinal fluid. The movable delivery element is disposed between the medication chamber and the pressure delivery chamber. The pressure source is coupled to the pressure delivery chamber. The control system is configured to selectively cause the pressure source to deliver pressure to the pressure delivery chamber causing the movable delivery element to apply pressure to the medicinal fluid in the medication chamber thereby causing the medicinal fluid to exit the medication chamber at an outlet along the fluid communication path to the patient.

A multi-night titration (MNT) process to find an optimal single therapeutic pressure of a CPAP device. This single therapeutic pressure can then be used on an on-going basis by the patient after the titration period. The MNT process differs from current auto adjusting processes used for titration (or ongoing use) in that the MNT process does not respond locally by adjusting pressures to individual events. With existing devices, the continuous adjustment of supplied air pressure always responds to one or a small number of events and thus fails to compensate for a patient's adaptation thereto, resulting in the supply of a less than optimal therapeutic pressure to the patient. While auto adjusting processes often capture and respond well to short-term and transient conditions, the MNT process of the current disclosure seeks to capture long term trends and find the most suitable average single pressure for a patient.

The present invention relates to a plurality of ventilation devices, to ventilation devices having visualization apparatuses, and to methods for operating the ventilation devices. The intent is to minimize the energy input into the at least one airway of a patient as a result of the ventilation.

A portable oxygen concentrator retrofit system and method in which an existing portable oxygen concentrator may be retrofitted to output an enriched oxygen gas at a flow rate suitable for use in a patient ventilation system without the need for an external source of compressed gas.

Materials and methods related to blood pump systems are described. These can be used in patients to, for example, monitor arterial pressure, measure blood flow, maintain left ventricular pressure within a particular range, avoid left ventricular collapse, prevent fusion of the aortic valve in a subject having a blood pump, and provide a means to wean a patient from a blood pump.