Search

EP-4378496-B1 - ARTIFICIAL LUNG SYSTEM AND ITS METHODS OF USE

EP4378496B1EP 4378496 B1EP4378496 B1EP 4378496B1EP-4378496-B1

Inventors

  • WU, ZHONGJUN
  • GRIFFITH, BARTLEY
  • WELLS, DAVID N.

Dates

Publication Date
20260506
Application Date
20151118

Claims (13)

  1. A method for providing gas for blood oxygenation not performed on a living human or animal body, said method comprising: providing an oxygen concentrator having a carbon dioxide scrubber; selectively operating the oxygen concentrator in a first operating mode comprising operating from battery power, and a second operating mode comprising -operating from an external power source; delivering oxygen from the oxygen concentrator without passing through the carbon dioxide scrubber to a blood oxygenator when the oxygen concentrator is operating in a the second operating mode; combining oxygen from the oxygen concentrator with a carbon dioxide-scrubbed oxygen gas stream from the carbon dioxide scrubber and delivering the combined gas stream to the blood oxygenator when the oxygen concentrator is operating in the first operating mode; and replacing the carbon dioxide scrubber when the oxygen concentrator is operating in the second operating mode; and. producing the carbon dioxide-scrubbed oxygen gas stream by scrubbing carbon dioxide from a carbon dioxide elevated gas stream received from the blood oxygenator.
  2. The method of claim 1, wherein the oxygen concentrator delivers a flow in the range from 0.5 LPM to 1 LPM to combine with the carbon dioxide-scrubbed oxygen gas stream.
  3. The method of claim 2, wherein the carbon dioxide scrubbed oxygen gas flow is from 4.5 to 9 LPM.
  4. The method of claim 1, wherein oxygen from the oxygen concentrator without scrubbing the carbon dioxide is delivered at a rate from 2 LPM to 6 LPM.
  5. The method of claim 4, further comprising combining the oxygen from the oxygen concentrator with a carbon dioxide elevated gas stream from the blood oxygenator when the oxygen concentrator is operating in the second operating mode.
  6. The method of claim 4, wherein the carbon dioxide elevated gas stream flows at a rate from 3 LPM to 6 LPM.
  7. An oxygen supply unit for a blood oxygenator which receives an oxygen rich gas flow and generates an elevated carbon dioxide gas flow, said oxygen supply unit comprising: an oxygen concentrator which produces an oxygen rich gas stream from air; a removable carbon dioxide scrubber which removes carbon dioxide from the elevated carbon dioxide gas flow; a power control configured to deliver power in one of at least two operating modes, wherein a first one of said at least two operating modes comprises operating from battery power, and wherein a second one of said at least two operating modes comprises operating from an external power source; and a valved tubing network configured (1) to deliver oxygen rich gas from the oxygen concentrator to a blood oxygenator without scrubbing when the oxygen concentrator is operating in the second one of said at least two operating modes; (2) to combine oxygen from the oxygen concentrator with a carbon dioxide-scrubbed oxygen gas stream and delivering the combined gas stream to the blood oxygenator when the oxygen concentrator is operating in the first one of said at least two operating modes; and (3) to produce the carbon dioxide-scrubbed oxygen gas stream by scrubbing carbon dioxide from the elevated carbon dioxide gas flow received from the blood oxygenator; wherein said oxygen supply unit is configured to enable replacement of said removable carbon dioxide scrubber when said power control is operating in said second one of said two operating modes.
  8. The oxygen supply unit of claim 7, wherein said removable carbon dioxide scrubber is connected to said oxygen supply unit through at least one quick disconnect fitting.
  9. The oxygen supply unit of claim 8, further comprising an enclosure wherein the oxygen concentrator, the carbon dioxide scrubber, the power control, and the valved tubing network are disposed within the enclosure.
  10. The oxygen supply unit of claim 8, wherein the oxygen concentrator comprises a pressure-swing oxygen concentrator having an electronically driven internal compressor.
  11. The oxygen supply unit of claim 8, wherein the carbon dioxide scrubber includes a canister having a scrubbing medium.
  12. The oxygen supply unit of claim 8, wherein the valved tubing network comprises a dehumidifier for removing moisture from the elevated carbon dioxide gas flow prior to passing said flow through the carbon dioxide scrubber.
  13. The oxygen supply unit as in claim 12, wherein the valved tubing network further comprises a pump for flowing the elevated carbon dioxide gas stream, and a bypass line which allows the oxygen rich gas to flow by the carbon dioxide scrubber.

Description

FIELD OF THE INVENTION The present invention generally relates to systems for oxygenating blood. BACKGROUND Lung failure occurs acutely or chronically. Lung disease is the number three killer in the United States and is responsible for one in six deaths. Chronic obstructive pulmonary disease (COPD) is one of the most common lung diseases and is the fourth leading cause of death in the U.S. Adult Respiratory Distress Syndrome (ARDS) is afflicting 190,000 patients yearly and the average survival is between 30-50% (Rubenfeld et al. N Engl J Med 2005;353:1685-93). If lung failure occurs, either mechanical ventilation or extracorporeal membrane oxygenation (ECMO) must be implemented to oxygenate the blood to maintain the oxygen requirements of the body. Mechanical ventilation is effective for short-term support, yet the sustained tidal volumes and airway pressures often used may damage the lungs. ECMO systems are an attractive alternative to mechanical ventilation since they closely simulate physiological gas exchange and extended ECMO support is possible via multiple device exchanges. But in practice, these systems are limited by the complexity of their operation, bleeding, and reduced patient mobility. The patients are often bedridden, resulting in muscular atrophy. Recently, ambulatory ECMO support has been implemented in a number of centers using available pumps and oxygenators, allowing patients to walk around and go outside. They can also eat and exercise. In spite of the benefits that current ECMO systems provide, they are still very bulky. They are also limited for extended use due to the functional lifespan of oxygenators. In consideration of the limitations described above, there is a need in the art for a system and method for providing mechanical oxygenation for an ambulating patient using a portable artificial lung system that is suited for extended use. Patents and published applications relevant to the subject matter of the present invention include US2013296633; US2011040241; US7682327; US6935344; US6503450; US5308320; US4548597; US4610656; and US3927981. DE 197 02 098 relates to a heart-lung machine includes a tubing set and has tube loops for supplying relates to a heart-lung machine including a tubing set and has tube loops for supplying to an artery, and extraction from a vein. The unit also includes an oxygenator, blood pump and oxygen dispenser. An oxygen concentrator dispenses oxygen and has a connected pump drive, with electrical connection supplied from a decentralised supply of electricity having a second connection for a battery. SUMMARY OF THE INVENTION The present invention is defined in the appended independent claims to which reference should be made. Advantageous features are set out in the appended dependent claims. . While the systems of the present invention are particularly suitable as portable systems, they may also be used as or as part of stationary systems. The present invention provides a compact, low-weight oxygen supply unit for a lung-assist oxygenator system that can deliver an oxygen flow rate typically in the range 0.5 to 3 liter per minute using a pressure-swing type oxygen concentrator in combination with a disposable carbon dioxide scrubber unit. The oxygen supply unit can run using battery power ("off-line" operation) or using AC or plug-in current ("on-line" operation). Use of the carbon dioxide scrubber increases battery life since the scrubber requires less power to recycle oxygen than does the oxygenation concentrator to produce oxygen. Not using the carbon dioxide scrubber while the system is powered from an external source, however, is preferable since the power source is unlimited and the life of the carbon dioxide scrubber can be extended (the scrubbing medium is not being consumed), allowing use of a smaller scrubber and/or less frequent scrubber exchange. In this way, the size and weight of the oxygen supply unit can be minimized and the battery operation time maximized. During off-line or battery operation, oxygen-rich gas from the oxygen supply unit enters the blood oxygenator where it exchanges oxygen for carbon dioxide and produces an exhaust gas having an increased carbon dioxide content. The amount of carbon dioxide, however, is not great. Rather than dumping this exhaust gas which still contains a high level of oxygen into the environment, the gas can be returned to the oxygen supply unit where it is scrubbed to remove the carbon dioxide, typically after removing water vapor. The scrubbed gas is recycled back to the blood oxygenator unit with the addition of a small flow of concentrated oxygen from the oxygen concentrator unit sufficient to replace the amount of oxygen which was transferred during the previous passage through the blood oxygenator. In this way, a high oxygen rich gas flow rate, on the order of 5 to 10 liters per minute, can be provided to the oxygenator using only 0.5 to 1 liters per minute of oxygen from the oxygen concentrator