Systems and method for delivery of therapeutic gas to patients, in need thereof, receiving breathing gas from a ventilator that varies at least pressure and/or flow using enhanced therapeutic gas (NO) flow measurement

Inventors

Acker, Jaron M. • Tolmie, Craig R.

Assignees

Mallinckrodt Pharma IP Trading DAC • Therakos Inc • INO Therapeutics LLC • Mallinckrodt Critical Care Finance Inc

Abstract

The present disclosure generally relates to systems and methods for delivery of therapeutic gas to patients, in need thereof, receiving breathing gas from a high frequency ventilator using at least enhanced therapeutic gas (e.g., nitric oxide, NO, etc.) flow measurement. At least some of these enhanced therapeutic gas flow measurements can be used to address some surprising phenomenon that may, at times, occur when wild stream blending therapeutic gas into breathing gas a patient receives from a breathing circuit affiliated with a high frequency ventilator. Utilizing at least some of these enhanced therapeutic gas flow measurements the dose of therapeutic gas wild stream blended into breathing gas that the patient receives can at least be more accurate and/or under delivery of therapeutic gas into the breathing gas can be avoided and/or reduced.

Core Innovation

The disclosure relates to a nitric oxide delivery system for delivering therapeutic gas into breathing gas in the inspiratory limb of a patient breathing circuit affiliated with a high frequency ventilator or ventilation techniques which provide reverse and/or oscillations in inspiratory pressure or flow. During wild stream proportional blending, rapid oscillatory/vibrational effects can cause a false NO flow phenomenon, where NO flow sensors indicate NO flow even when NO is not truly flowing, resulting in underdosing and dose inaccuracies, including under-delivery.

To address this, the system includes at least one control valve providing a flow of therapeutic gas, an injector module coupled to the inspiratory limb, and a therapeutic gas inlet configured to receive and inject therapeutic gas into the injector module and into patient breathing gas. At least one NO flow sensor is provided in fluid communication with the therapeutic gas inlet, and a control system receives flow information from the NO flow sensor.

The control system detects use of the high frequency ventilator and compensates for false NO flow phenomenon by treating flow information generated by the high frequency ventilator as noise and filtering the noise out and/or using noise reduction techniques. The control system further compensates by identifying flow information as missing and interpolating missing flow information, and/or identifying flow information as reverse flow and inverting the value of the flow information. A variant specifies at least one bi-directional NO flow sensor capable of measuring flow in a forward direction and in a reverse direction, providing bi-directional flow information for the control system.

Claims Coverage

Independent claim coverage includes two independent claims. The claims share a common core architecture and add specific inventive control actions to detect high frequency ventilator conditions and compensate for false NO flow phenomenon using noise filtering, interpolation of missing flow information, and inversion for reverse flow; one claim further emphasizes bi-directional NO flow sensing with forward and reverse flow information.

The independent claims cover an NO delivery system that uses NO flow sensing in the inspiratory limb injection path together with a control system that detects high frequency ventilator use and compensates for false NO flow phenomenon through noise reduction, interpolation of missing flow, and inversion for reverse flow. A related independent claim specifies bi-directional NO flow sensing to provide forward and reverse flow information to the control system.

Stated Advantages

Documented Applications