Abstract: Methods and apparatus for concentration determination using polarized light. The apparatus includes a first polarized light source having a first light source polarization axis and a second polarized light source having a second light source polarization axis generally perpendicular to the first light source polarization axis. Also, a first polarized light receiver having a first polarized light receiver polarization axis and configured to measure an intensity of light transmitted from the first light receiver polarizer and a second polarized light receiver having a second polarized light receiver polarization axis substantially perpendicular to the first light receiver polarization axis and configured to measure an intensity of light transmitted from the second light receiver polarizer, wherein the first and second light receiver polarization axes are generally +/?45 degrees relative to the first and second light source polarization axes.

Abstract: Components for a medical infusion fluid handling system, such as an APD system, in which one or more lines (30) (such as solution lines), spikes (160) or other connection ports may be automatically capped and/or de-capped. This feature may provide advantages, such as a reduced likelihood of contamination since no human interaction is required to de-cap and connect the lines, spikes or other connections. For example, a fluid handling cassette (24) may include one or more caps (63) that cover a corresponding spike (160) and include a raised and/or recessed feature to assist in removal of the cap from the cassette. A solution line cap (31) may include a hole and recess, groove or other feature to engage with a spike cap enable removal of the cap.

Abstract: A medical infusion fluid handling system, such as an APD system, may be arranged to de-cap and connect one or more lines (30) (such as solution lines) with one or more spikes (160) or other connection ports on a fluid handling cassette (24). This feature may reduce a likelihood of contamination since no human interaction is required to de-cap and connect the lines and spikes. For example, an APD system may include a carriage (146) arranged to receive a plurality of solution lines (30) each having a connector end (31a) and a cap (31). The carriage may move along a first direction so as to move the connector ends of the solution lines along the first direction, and a cap stripper (149) may be arranged to engage with caps on the solution lines on the carriage. The cap stripper may move in a second direction transverse to the first direction, as well as to move with the carriage along the first direction.

Abstract: An occluder (147), and methods for occlusion, that employs first and second opposed occluding members (165) associated with each other, a tube contacting member (161) connected to, or comprising at least a portion of, at least one of the first and second occluding members, and a force actuator (166) constructed and positioned to apply a force to at least one of the first and second occluding members. Application of the force by the force actuator may cause the tube contacting member to move between a tube occluding and an open position. A release member (169) may be configured and positioned to enable an operator to manually move the tube contacting member from the tube occluding position to the open position even with no force applied to the occluding member by the force actuator.

Abstract: A fluid handling cassette (24), such as that useable with an APD cycler device or other infusion apparatus, may include a generally planar body having at least one pump chamber (181) formed as a depression in a first side of the body and a plurality of flowpaths for fluid that includes a channel. A patient line port may be arranged for connection to a patient line (34) and be in fluid communication with the at least one pump chamber via at least one flowpath, and an optional membrane (15) may be attached to the first side of the body over the at least one pump chamber. In one embodiment, the membrane may have a pump chamber portion (151) with an unstressed shape that generally conforms to the pump chamber depression in the body and is arranged to be movable for movement of fluid in the useable space of the pump chamber. One or more spacers (50) may be provided in the pump chamber to prevent a pump membrane from contacting an inner wall of the pump chamber.

Abstract: Methods and apparatus for concentration determination using polarized light. The apparatus includes a first polarized light source having a first light source polarization axis and a second polarized light source having a second light source polarization axis generally perpendicular to the first light source polarization axis. Also, a first polarized light receiver having a first polarized light receiver polarization axis and configured to measure an intensity of light transmitted from the first light receiver polarizer and a second polarized light receiver having a second polarized light receiver polarization axis substantially perpendicular to the first light receiver polarization axis and configured to measure an intensity of light transmitted from the second light receiver polarizer, wherein the first and second light receiver polarization axes are generally +/?45 degrees relative to the first and second light source polarization axes.

Abstract: Methods and apparatus for concentration determination using polarized light. The apparatus includes a first polarized light source having a first light source polarization axis and a second polarized light source having a second light source polarization axis generally perpendicular to the first light source polarization axis. Also, a first polarized light receiver having a first polarized light receiver polarization axis and configured to measure an intensity of light transmitted from the first light receiver polarizer and a second polarized light receiver having a second polarized light receiver polarization axis substantially perpendicular to the first light receiver polarization axis and configured to measure an intensity of light transmitted from the second light receiver polarizer, wherein the first and second light receiver polarization axes are generally +/?45 degrees relative to the first and second light source polarization axes.