摘要:
A method correlates average fiber diameter with performance for a complex filtration media comprising a matrix of fibers having a fibrillated component with a diameter so small (e.g., less than 0.01 microns), that cannot be physically measured with accuracy. The method manufactures a selected matrix, derives the number average diameter of the fibers according to prescribed steps, some of which do not require actual physical measurements, and observes a performance characteristic. The method repeats the foregoing steps for different matrixes, yielding different number average diameters. The method expresses change in the selected performance characteristic as a function of change in number average diameter of the matrices.
摘要:
An intravenous (“IV”) liquid delivery system includes: an IV pump tubing set; a shuttle pump or membrane pump actuator operable with the IV pump tubing set; upstream and downstream valve actuators operable with the IV pump tubing set; the IV pump tubing set including an air removal device; an air detector configured to sense air in the IV pump tubing set; a control unit configured and arranged to (i) open the upstream valve actuator and close the downstream valve actuator to allow the pump actuator to draw liquid into a pump actuation portion of the IV pump tubing set, and (ii) close the upstream valve actuator and open the downstream valve actuator to allow the pump actuator to push liquid out of the pump actuation portion, the system configured to attempt to remove the air via the air removal device while operating the upstream and downstream valve actuators according to (i) and (ii).
摘要:
A priming indicator for a fluid infusion system includes a luer cap or other component of the infusion system having an indicator surface covered by a membrane. The membrane exhibits a first visual characteristic, such as being opaque, when dry and exhibits a second characteristic, such as becoming less opaque, when wet. Once the membrane becomes wet, indicia on the surface, which may be provided on a rod at least partially covered by the membrane, becomes visible, thereby indicating an intravenous tube to which the luer cap is secured has been primed or is nearly primed. The indicator may alternately be employed at an upstream end of an infusion set, such as at the port of a medical bag providing a supply of fluid, to indicate a low level of fluid in the medical bag.
摘要:
A filter for removing leukocytes from blood comprises a filter media enclosed in a housing. The filter media includes a main filter region comprising a porous membrane structure extending between first and second skin surfaces. The porous membrane structure is formed by intersecting cells having a range of diameters. The cells adjacent to the first skin surface have diameters generally smaller than the diameters of the cells adjacent to the second skin surface. The first skin surface includes an open area defined by pores, which are formed by the intersection of cells with the first skin surface. The majority of the open area is defined by pores having a diameter of between about 12 &mgr;m and 28 &mgr;m.
摘要:
A device and method for inactivating pathogens in therapeutic fluids with sterilizing radiation in a continuous thin fluid flow arrangement that exhibits radiation dose uniformity for fluids having high optical densities. Radiation dose uniformity is achieved in part through a “carrying” mechanism that moves or carries the fluid, thereby eliminating a channel flow velocity profile where flow volumes near the channel walls run the risk of overexposure to the radiation due to very large residence times within the channel. The device comprises a relatively flat belt chamber (22) connected to a fluid flow through an inlet (24) and an outlet (26) on the belt chamber (22). The belt chamber (22) has a top surface (28) and a bottom surface (30). A radiation permeable plate (32) is disposed adjacent the top surface (28) of the belt chamber (22) and is in contact with the belt chamber (22). A radiation source (42) is provided adjacent to the plate (32) adjacent to a side opposite the belt chamber (22). A belt (34) having a plurality of flexible vanes (36) is disposed adjacent the bottom surface (30) of the belt chamber (22) such that the vanes (36) make contact with the belt chamber (22). The belt is driven by a roller mechanism (38) in the direction of the fluid flow. As the fluid flows through the belt chamber (22), the flexible vanes (36) provide a squeegee-like mechanism to move the fluid through the belt chamber (22) in discrete packets (40) defined by a pair of vanes (36). As the packets of fluid move through the belt chamber, they are exposed to sterilizing radiation passing through the plate (32).
摘要:
A permeable structure forms a chamber to hold living cells. The structure includes a first permeable region surrounding at least a portion of the chamber having a conformation that, when implanted in host tissue, substantially blocks penetration of host cells into the chamber while permitting solute transport. The structure also includes a second permeable region overlying the first permeable region having a conformation that, when implanted in host tissue, forms a permeable interface with host tissue that permits solute transport. A third permeable region is located between the first and second permeable regions. The third region comprises a solution of polymer material formed in place between the first and second permeable regions. The third permeable region bonds the first and second permeable regions together. The third permeable region also has a conformation that, when implanted in host tissue, permits solute transport between the first and second permeable regions. The third, formed-in-place region bonds the first and second permeable regions together, providing a robust, laminated structure that resists delamination during implantation caused by cellular infiltration into discontinuous spaces between the first and second regions. The third, formed-in-place region can also have a conformation providing an immunoisolation effect. Furthermore, the permeability of the third, formed-in-place membrane is sufficient high that it does not adversely effect the permeability value desired for the overall multiple layer membrane structure.
摘要:
An access device including access site is disclosed for providing access to a medical fluid flow path for the introduction or withdrawal of medical fluids to and from the flow path. The access device includes an indicator for providing a visual indication when the access device has been exposed to an antiseptic agent.
摘要:
The present invention provides a method for preparing submicron-sized particles. The method includes the steps of: (1) providing a multiphase system having an organic phase and an aqueous phase, the organic phase having a pharmaceutically effective compound therein; and (2) sonicating the system to evaporate a portion of the organic phase to cause precipitation of the compound in the aqueous phase and having an average effective particle size of less than about 2 m.
摘要:
Membranes and methods for making membranes are disclosed. The membranes include a polymeric matrix and a particulate material immobilized within the matrix. The membranes may find particular application in methods and apparatus for removing organic compounds from a biological fluid as part of a pathogen inactivation treatment.
摘要:
A device and method for inactivating pathogens in therapeutic fluids with sterilizing radiation in a continuous flow arrangement while exhibiting radiation dose uniformity and narrow residence time distribution of the fluid within the device. The device (10) comprises a radiation permeable cylindrical tube (12) having a concentric cylindrical rotor (14) disposed therein, thereby providing a thin gap (16) therebetween. A top plate (18) having a fluid outlet (26) and a bottom plate (20) having a fluid inlet (24) seal the cylindrical tube (12). The inlet (24) and outlet (26) are both in fluid communication with the thin gap (16). A rotor shaft (36) is disposed axially through the cylindrical rotor (14) and is connected to a motor (30). A pump provides fluid flow through the device (10). A radiation source provides sterilizing radiation to the fluid through the cylindrical tube (12). As the fluid flows, the motor (30) drives the rotor (14) to impart Taylor vortices to the fluid flow, which exchanges the fluid closer to the cylindrical tube (12) with the fluid closer to the rotor (14).