A method of dispensing fluid includes three processes. A first one of these processes includes pumping fluid into a resilient variable-volume dispensing chamber. The dispensing chamber is in series with a normally present finite fluid impedance and an output. The impedance is sufficient so as to cause expansion of the dispensing chamber as it receives pumped fluid even while some fluid flows through the output. Another one of these processes includes repeatedly measuring a parameter related to volume of the dispensing chamber over time. A third one of these processes includes controlling the pumping of fluid based on repeated measurements of the parameter to produce a desired fluid flow through the output. A corresponding system for dispensing fluid implements these processes.

This invention relates to a surgical smoke evacuation system for use in removing gases and smoke created in surgical procedures form within an insufflated surgical cavity. Such a system comprises a discharge assembly adapted to form a gases path, and having an end which in use is located within said surgical cavity so that gases and/or surgical smoke inside said cavity can pass out of said cavity and through said discharge assembly along said gases path, a flexible discharge limb having an operational site end and an outlet end, and a self-supporting wall defining a gases flow passage between said operational site end and said outlet end, in use said open operational site end sealingly connected to said discharge assembly so that said gases and/or surgical smoke can pass out of said discharge assembly and into said discharge limb, a filter connected in use to the outlet end of the discharge limb, at least part of said wall of the discharge limb formed from a breathable material, said breathable material allowing the passage of water vapour through the wall of the discharge limb without allowing the passage of liquid water or surgical smoke or other gases.

This invention relates to a surgical smoke evacuation system for use in removing gases and smoke created in surgical procedures form within an insufflated surgical cavity. Such a system comprises a discharge assembly adapted to form a gases path, and having an end which in use is located within said surgical cavity so that gases and/or surgical smoke inside said cavity can pass out of said cavity and through said discharge assembly along said gases path, a flexible discharge limb having an operational site end and an outlet end, and a self-supporting wall defining a gases flow passage between said operational site end and said outlet end, in use said open operational site end sealingly connected to said discharge assembly so that said gases and/or surgical smoke can pass out of said discharge assembly and into said discharge limb, a filter connected in use to the outlet end of the discharge limb, at least part of said wall of the discharge limb formed from a breathable material, said breathable material allowing the passage of water vapour through the wall of the discharge limb without allowing the passage of liquid water or surgical smoke or other gases.

Fluid introduction into the patient during surgery can be tracked more accurately. For example, saline is often introduced to a patient to clean an operating site. The saline is taken from a sterile bucket and introduced to the patient. In one described approach, the system senses the volume or weight of fluid in the sterile bucket and determines any decrease in the volume or weight to be an introduction of fluid to the patient. If, however, additional saline is added to the bucket, that addition is not counted in the fluid tracking and the further decrements from that new fluid amount is what is used to track fluid addition to the patient.

Fluid introduction into the patient during surgery can be tracked more accurately. For example, saline is often introduced to a patient to clean an operating site. The saline is taken from a sterile bucket and introduced to the patient. In one described approach, the system senses the volume or weight of fluid in the sterile bucket and determines any decrease in the volume or weight to be an introduction of fluid to the patient. If, however, additional saline is added to the bucket, that addition is not counted in the fluid tracking and the further decrements from that new fluid amount is what is used to track fluid addition to the patient.

A residual gas volume measuring device for measuring volume of residual gas in a container filled with liquid. The device includes: a puncture member having a first communication path and a second communication path formed therein and connecting a penetrating portion and a coupling portion together, the penetrating portion being located inside the container and the coupling portion being located outside the container when the puncture member is in a penetrating position where an end of the puncture member penetrates into the container; an injection section coupled to the first communication path at the coupling portion and configured to inject a liquid into the container; a discharging section coupled to the second communication path at the coupling portion and configured to discharge the residual gas purged by the injected liquid; and a measurement section configured to measure the volume of the residual gas discharged by the discharging section.

An air extracting device (2) at least includes a processor (21), a motor (23), an air-extracting unit (24), and a wireless transmitting unit (25), and a method of the air extracting device (2) for calculating remaining time required for extracting action includes following steps: activating the motor (23) after the air extracting device (2) and a sealed bag (1) are jointed together; driving the air-extracting unit (24) to execute an extracting action by the activated motor (23) for extracting air from the sealed bag (1); monitoring load current of the motor (23) by the processor (21) while executing the extracting action; calculating a remaining time required for the extracting action by the processor (21) according to a variation of the load current; and, transmitting the remaining time required for the extracting action to a mobile device (4) through the wireless transmitting unit (25) for displaying thereon.

A method for optimizing pressure exchange includes providing a first pressure exchange system comprising an energy recovery device (ERD). A second system supplies high-pressure fluid, energized by a positive displacement pump, to the ERD. A third system supplies low-pressure fluid to the ERD. The first system energizes the low-pressure fluid with the high-pressure fluid to form a high-pressure fracking fluid, which is delivered from the first system to a well-head. A rate of required flow is input into a control system, which determines a rate of flow of the high-pressure fluid, a rate of flow of the low-pressure fluid, and an actual rate of flow of the fracking fluid at the well-head. The control system then adjusts to equilibrium: the rate of flow of the high-pressure fluid based on the actual rate of flow; and the rate of flow of the low-pressure fluid based on the actual rate of flow.

A method for optimizing pressure exchange includes providing a first pressure exchange system comprising an energy recovery device (ERD). A second system supplies high-pressure fluid, energized by a positive displacement pump, to the ERD. A third system supplies low-pressure fluid to the ERD. The first system energizes the low-pressure fluid with the high-pressure fluid to form a high-pressure fracking fluid, which is delivered from the first system to a well-head. A rate of required flow is input into a control system, which determines a rate of flow of the high-pressure fluid, a rate of flow of the low-pressure fluid, and an actual rate of flow of the fracking fluid at the well-head. The control system then adjusts to equilibrium: the rate of flow of the high-pressure fluid based on the actual rate of flow; and the rate of flow of the low-pressure fluid based on the actual rate of flow.

Provided are systems and methods for line volume calibration, and measurement of fluid samples delivered to an interrogation point. In various embodiments, a known fluid volume comprising a sample line fluid and a secondary fluid is delivered to a fluid boundary sensor. The fluid boundary sensor assists in determining the position of the boundaries between the various fluids, and the positions of these boundaries are used to determine the sample line fluid volume.