A device for determining the access flow rate of a patient when connected to a blood treatment machine performs a measurement phase (40), in which the blood treatment machine is caused (41, 43) to operate in first and second operating states, wherein the second operating state at least differs from the first operating state by a change of flow direction of blood or treatment fluid through a dialyzer of the blood treatment machine. Based on sensor values representing a fluid property (42, 44) of the treatment fluid in the first and second operating states, the device computes (45) a measurement value of comparison parameter (e.g. a ratio or a difference) that compares treatment efficiency in the first operating state to treatment efficiency in the second operating state, and determines (46), based on the measurement value, an estimated value of the access flow rate.

Provided is a chamber configuration for a reverse flow centrifuge, and a reverse flow centrifuge system configured for low fluid volume and small radius rotation. The compact reverse flow centrifuge system has a reusable subsystem and a single use replaceable subsystem. The replaceable subsystem comprises a separation chamber, fluid delivery manifold and rotational mounting connecting the separation chamber to the fluid manifold. The single use replaceable subsystem provides a closed environment for execution of reverse flow centrifugation processes. The separation chamber has a substantially conical fluid enclosure portion connected to a neck portion, and a dip tube extends centrally through the conical fluid enclosure to provide a fluid path to the tip of the conical fluid enclosure.

A device is disclosed for determining an access flow rate of a patient when connected to a blood treatment machine. The device performs a measurement phase in which the blood treatment machine is caused to operate in first and second operating states, where the second operating state at least differs from the first operating state by a change of flow direction of blood or treatment fluid through a dialyzer of the blood treatment machine. Based on sensor values representing a fluid property of the treatment fluid in the first and second operating states, the device computes a measurement value of comparison parameter (e.g. a ratio or a difference) that compares treatment efficiency in the first operating state to treatment efficiency in the second operating state, and determines, based on the measurement value, an estimated value of the access flow rate.

A system for perfusing a localized site within a body includes a catheter assembly having a venous access line that is adapted to deliver perfusate to the localized site, a venous or arterial drainage line adapted to drain perfusate from the localized site, and an occlusion device adapted to prevent some or substantially all physiological blood flow between the localized site and the systemic circulation of the body during and in the course of perfusing and draining perfusate to and from the localized site. The system may include a blood circuit associated with the catheter assembly to facilitate blood conditioning for use as the perfusate, in the course of a controlled perfusion and/or drainage of untreated, treated, or inactivated treated blood to and from the localized site. A delivery machine may control the blood circuit and catheter assembly in order to both deliver perfusate to, and drain some or all perfusate from, the localized site in a manner that provides perfusate to substantially only the localized site.

A system for perfusing a localized site within a body includes a catheter assembly having a venous access line that is adapted to deliver perfusate to the localized site, a venous or arterial drainage line adapted to drain perfusate from the localized site, and an occlusion device adapted to prevent some or substantially all physiological blood flow between the localized site and the systemic circulation of the body during and in the course of perfusing and draining perfusate to and from the localized site. The system may include a blood circuit associated with the catheter assembly to facilitate blood conditioning for use as the perfusate, in the course of a controlled perfusion and/or drainage of untreated, treated, or inactivated treated blood to and from the localized site. A delivery machine may control the blood circuit and catheter assembly in order to both deliver perfusate to, and drain some or all perfusate from, the localized site in a manner that provides perfusate to substantially only the localized site.

Provided is a chamber configuration for a reverse flow centrifuge, and a reverse flow centrifuge system configured for low fluid volume and small radius rotation. The compact reverse flow centrifuge system has a reusable subsystem and a single use replaceable subsystem. The replaceable subsystem comprises a separation chamber, fluid delivery manifold and rotational mounting connecting the separation chamber to the fluid manifold. The single use replaceable subsystem provides a closed environment for execution of reverse flow centrifugation processes. The separation chamber has a substantially conical fluid enclosure portion connected to a neck portion, and a dip tube extends centrally through the conical fluid enclosure to provide a fluid path to the tip of the conical fluid enclosure.

An ambulatory ultrafiltration device includes a blood filter that has a blood side or fluid communication with the vascular system of the subject, an ultrafiltrate side, and a semipermeable membrane disposed between the blood side and the ultrafiltrate side. The ambulatory ultrafiltration also includes a buffer vessel in fluid communication with the blood side of the blood filter, and a blood pump. The blood pump is controlled to alternate between a withdrawal phase and a return phase. In the withdrawal phase, blood is withdrawn on a blood path from the subject via the blood filter to the buffer vessel. In the return phase, blood is returned from the buffer vessel to the subject on the blood path. The blood filter is arranged to remove ultrafiltrate from the blood during at least one of the withdrawal and return phases.

A fluid management system may include a fluid pump capable of generating a pulsatile flow of fluid, a fluid pathway for transporting the pulsatile flow of fluid from a fluid source through the fluid pump to a medical device, a dampening element in fluid communication with the fluid pathway and operably independent of the fluid pump, the dampening element comprising one or more barrels, each barrel including a movable seal member disposed within the barrel and a biasing member disposed within the barrel and engaged with the movable seal member, the dampening element being responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations, and a fluid flow sensor disposed along the fluid pathway between the dampening element and the medical device to measure a flow rate of the smoothened pulsatile fluid flow in both flow directions.

A fluid management system may include a fluid pump capable of generating a pulsatile flow of fluid, a fluid pathway for transporting the pulsatile flow of fluid from a fluid source through the fluid pump to a medical device, a dampening element in fluid communication with the fluid pathway and operably independent of the fluid pump, the dampening element comprising one or more barrels, each barrel including a movable seal member disposed within the barrel and a biasing member disposed within the barrel and engaged with the movable seal member, the dampening element being responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations, and a fluid flow sensor disposed along the fluid pathway between the dampening element and the medical device to measure a flow rate of the smoothened pulsatile fluid flow in both flow directions.