Monitoring and controlling output pressue of pump associated with perfusion of liquids through organs/tissue; organ transport and transplantation; decreasing reperfusion injuries

Inventors

Millis, Roger • Foley, John • Schein, Doug • Brassil, John

Assignees

Organ Recovery Systems Inc

Abstract

A method for controlling a pump for delivery of liquid to an organ over a series of fixed-length time intervals f, each interval f comprising a time t1 and a time t2 wherein t1+t2 equals the length of interval f. The method comprises allowing output pressure of the pump to decrease over time t1, increasing output pressure of the pump over time t2, comparing achieved pump output pressure to a predetermined pressure at about the end of interval f, and at least one of (i) adjusting t1 and t2 if necessary so the predetermined pressure is approximated by the output pressure at the end of the next interval f, and (ii) adjusting a rate of change of the output pressure during at least one of t1 and t2 if necessary so the predetermined pressure is approximated by the output pressure at the end of the next interval f.

Core Innovation

The document describes a computer-executable method and corresponding apparatus for controlling a pump that delivers a liquid to an organ or tissue over a repeated series of fixed-length time intervals f. Each interval f includes a time t1 and a time t2 such that t1+t2 equals the length of interval f. During t1, the output pressure of the pump decreases over time t1, and during t2, the output pressure increases over time t2.

For each interval f, the method compares the achieved pump output pressure to a predetermined pressure at about the end of interval f. Based on the comparison, the method determines whether it is necessary to adjust t1 and t2 and/or adjust a rate of change of the output pressure during at least one of t1 and t2. The purpose of the adjustments is so that the predetermined pressure is approximated by the output pressure at the end of the next interval f.

The document further provides that at least one of adjusting t1 and t2 if necessary, and adjusting a rate of change of the output pressure during at least one of t1 and t2 if necessary, is performed based on the determination. In the apparatus implementations, a microprocessor and corresponding controller means perform the pressure decrease, pressure increase, comparison, determining, and performing steps, including implementations in which decreasing and increasing pressure are carried out by activating and deactivating the pump.

Claims Coverage

The provided claim set contains three independent claims: clm-00001, clm-00018, and clm-00019, with additional independent coverage indicated for clm-00029 as well. Across these independent claims, the inventive features focus on closed-loop pump output pressure control using repeated fixed-length intervals f split into t1 and t2, with comparison to a predetermined pressure at about the end of each interval and interval-to-interval adjustment of t1/t2 and/or a rate of pressure change so that the predetermined pressure is approximated at the end of the next interval.

Across the independent claims, the coverage centers on interval-based pump output pressure control in which pressure is decreased during t1 and increased during t2 within repeated fixed-length intervals f. The system compares achieved pump output pressure to a predetermined pressure at about the end of each interval, determines whether adjustments are necessary to approximate that predetermined pressure at the end of the next interval, and performs adjustments by modifying t1 and/or the rate of change of the output pressure. Apparatus claims implement these functions using a microprocessor/controller or corresponding means, including implementations where pressure decrease/increase is effected by activating/deactivating the pump.

Stated Advantages

Documented Applications

No documented applications found