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US-12616190-B2 - System and method for ventilating an organ

US12616190B2US 12616190 B2US12616190 B2US 12616190B2US-12616190-B2

Abstract

A system and method for maintaining the vitality of an organ through negative pressure ventilation and perfusion. The system includes fluidically coupled components: an organ enclosure, a diaphragm enclosure, an actuator/pump, a perfusion system, and a reservoir. The actuator can displace a precise amount of a working fluid that displaces that precise amount of a sterile support fluid. The sterile fluid travels between the diaphragm enclosure and the organ enclosure, thereby ventilating the organ within the organ chamber. The perfusion system circulates a perfusate through the organ.

Inventors

  • Michael C. Tilley
  • Steven L. Henning
  • Joshua Filgate
  • Stuart A. Jacobson
  • Daniel S. Karol

Assignees

  • DEKA PRODUCTS LIMITED PARTNERSHIP

Dates

Publication Date
20260505
Application Date
20220808

Claims (18)

  1. 1 . A system for negative pressure ventilation of an organ comprising: an actuator configured to cause a first fluid to be displaced by a first volume; a diaphragm enclosure housing a flexible membrane, the flexible membrane having two surfaces, one of the two surfaces fluidically coupled with the first fluid, another of the two surfaces fluidically coupled with a second fluid, the flexible membrane displacing the second fluid by the first volume when the actuator causes the first fluid to be displaced; and an organ enclosure housing the organ, the organ enclosure being fluidically coupled with the diaphragm enclosure, the organ enclosure receiving the second fluid from the diaphragm enclosure when the actuator causes the first fluid to be displaced, wherein displacement of the second fluid enables the negative pressure ventilation of the organ.
  2. 2 . The system as in claim 1 further comprising: at least one sensor configured to collect sensor data.
  3. 3 . The system as in claim 2 wherein the at least one sensor comprises: a tidal volume sensor configured to collect tidal volume sensor data during the negative pressure ventilation; and a pressure sensor configured to sense pressure of the second fluid during the negative pressure ventilation.
  4. 4 . The system as in claim 2 wherein the at least one sensor comprises: a bubble sensor configured to collect bubble sensor data during a priming process.
  5. 5 . The system as in claim 2 further comprising: at least one controller configured to execute instructions, the instructions configured to control the actuator.
  6. 6 . The system as in claim 5 wherein the instructions comprise: receiving the sensor data; and controlling the actuator based at least on the sensor data.
  7. 7 . The system as in claim 5 further comprising: a reservoir holding the second fluid, the reservoir being fluidically coupled with the diaphragm enclosure.
  8. 8 . The system as in claim 7 wherein the instructions comprise: receiving bubble sensor data from a bubble sensor, the bubble sensor being fluidically coupled with the reservoir and the organ enclosure; and moving an amount of the second fluid from the reservoir to the organ enclosure, the amount being based on the bubble sensor data.
  9. 9 . The system as in claim 5 further comprising a perfusion system including: at least one perfusion pump; a gas management system including an enclosure configured to expose perfusate to gas; a thermal management system adjusting a temperature of fluid exiting the gas management system to create thermally-adjusted fluid; and a perfusate reservoir including a fluid enclosure configured to hold the thermally-adjusted fluid destined for the organ, the perfusate reservoir configured to receive perfusate to mix with the thermally-adjusted fluid forming a mixed fluid, the perfusate reservoir including a drain configured to discharge excess thermally-adjusted fluid and/or mixed fluid.
  10. 10 . The system as in claim 9 further comprising a fluid path including: at least one venous sensor configured to determine characteristics of venous fluid; and at least one arterial sensor configured to determine characteristics of arterial fluid, wherein the instructions include controlling the perfusion pump, the gas management system, and the thermal management system, the instructions configured to pump the venous fluid from the organ through the gas management system and the thermal management system and into the organ.
  11. 11 . The system as in claim 9 wherein the perfusion system comprises: at least one venous fluid sample port.
  12. 12 . The system as in claim 9 wherein the perfusion system comprises: at least one venous sensor.
  13. 13 . The system as in claim 9 wherein the perfusion system comprises: at least one arterial fluid sample port.
  14. 14 . The system as in claim 9 wherein the perfusion system comprises: at least one arterial sensor.
  15. 15 . The system as in claim 9 wherein the perfusate is a blood-based fluid.
  16. 16 . The system as in claim 9 wherein the perfusate is oxygen-carrying molecules.
  17. 17 . The system as in claim 1 further comprising: a portable enclosure enclosing the actuator, the flexible membrane, and the organ enclosure; and a portable power supply.
  18. 18 . The system as in claim 9 further comprising: a portable enclosure enclosing the actuator, the flexible membrane, the organ enclosure, and the perfusion system; and a portable power supply.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application Ser. No. 63/260,097, filed Aug. 9, 2021, entitled SYSTEM AND METHOD FOR VENTILATING AN ORGAN which is incorporated herein by reference in its entirety. BACKGROUND This disclosure relates generally to a system for controlling airflow into an organ. To provide airflow to an organ, positive pressure or negative pressure can be used to move the air. When positive pressure is applied, air is moved into the organ, forcing the organ to expand. When negative pressure is applied, the organ is expanded, drawing air into the organ. Negative pressure ventilation (NPV) has been used in vivo as assistive breathing for patients afflicted with, for example, polio. Certain actions on organs require the organs to be situated ex vivo and ventilated for more than a threshold amount of time. These actions include, but are not limited to, laboratory study of the organs and transport/maintenance/monitoring/repairing of organs for transplant. NPV can be performed by, for example, extracting air from a bioreactor holding the organ, forcing the organ to expand and draw in air, simulating inhalation. The process can be reversed, i.e. providing air to the bioreactor, forcing the organ to contract and release the air, simulating exhalation. This two-step process is used as an improvement over using only positive pressure, which can induce injury to the organ. Current NPV systems have limitations including, but not limited to, (1) reacting to changes in compressibility or other material properties of hydraulic fluids during operation (temperature dependency, deterioration/separation), (2) being subject to air bubbles inside either hydraulic fluid chamber, as a result from insufficient system priming, system leaks, or bubble generation during operation, (3) experiencing elasticity of the diaphragm membrane between the hydraulic fluids, along the thickness of the material, (4) experiencing elasticity of a scaffold/tissue (external volume expansion not equal to internal volume expansion), (5) experiencing elasticity/lack of rigidity in the hydraulic system (chambers, tubing), (6) experiencing leaks from improper seals around the hydraulic piston or system fittings, (7) experiencing backlash in the piston linear actuator, (8), experiencing airway restrictions or obstructions, (9) improper or inadequate locations of sensors in hydraulic pathways and airway, and (10) sub-optimal methods and assumptions used to determine parameters if direct measurements are not taken (tidal volume calculated from airway flowrates). The above-described background is merely intended to provide a contextual overview of some current issues, and is not intended to be exhaustive. SUMMARY The system of the present teachings generates cyclic ventilation of an organ through a fluidically-coupled diaphragm. A NPV system controls airflow into and out of the organ. In as aspect, the system of the present teachings measures various pressures, tidal volume, and temperature parameters in order to track and assess organ performance. In an aspect, materials and environments contacting the organ are sterile. The organ is submerged in a sterile support fluid, to provide moisture to the exterior of the organ. The sterile support fluid is coupled to a working hydraulic fluid by way of an elastic, impermeable diaphragm membrane. The working hydraulic fluid is actuated with a low-pressure piston in a pumping chamber. The perfusion loop supplying the organ with a blood perfusate solution is connected to the organ artery and vein. The system can include sensors to measure the parameters such as, but not limited to, support fluid temperature, perfusate temperature, pulmonary flowrate, pulmonary or arterial pressure, inspiratory tidal volume, peak inspiration pressure, (also called peak airway pressure), inspiratory air temperature and humidity, and positive end-expiratory pressure. The system includes the capability to measure these parameters in order to plot the pressure-volume relationships and calculate the dynamic compliance of the organ tissue. All parts can be sterile single use, or there can be a combination of single use and autoclavable parts. The organ bioreactor of the present teachings can include a reservoir chamber and an organ chamber containing sterile support fluid, a working fluid chamber containing working hydraulic fluid, also referred to herein as working fluid, and a diaphragm in a diaphragm chamber separating the sterile support fluid from the working fluid. The reservoir chamber can be used to prepare the system for operational use, for example, for priming the system. The organ bioreactor and actuator can be used to accomplish the ventilation operation. The diaphragm allows the sterile and working fluids to be coupled. For example, as the working fluid is drawn out of the diaphragm chamber by the actuator, the diaphragm deforms and sterile fluid is draw