Baxter Travenol Laboratories, Inc.

Baxter International Inc.

Michael O Pekkarinen

Paul R Prince

Shmuel Sternberg

David Bellamy, Jr

Herbert Mittleman

James H Brauker

Ludwig Wolf, Jr

Norm Shim

Walker P Woodworth

Robert Assenheimer

A porous three dimensional structure for implantation in a host animal capable of producing an inflammatory foreign body response. The structure includes first and second layers spaced by a plurality of posts having a predetermined length connecting the first and second layers. Each of the layers has a plurality of openings of a predetermined size permitting fluids and inflammatory cells of the animal to pass through the openings and migrate into an interior volume defined by the first and second layers. The size of the openings and length of the posts promote a non-flattened morphology of the cells. The structure promotes vascularization adjacent to the structure when implanted into the animal.

Porous three dimensional structure

A method and apparatus for filtering suspensions of medical and biological fluids, one aspect of which is separating a suspension comprising at least two types of particles which are differently sized or shaped and in which the first type of particle may be deformable at a relatively lower force and/or faster rate than the second type of particle. A filter member is provided having substantially precisely dimensioned pore sizes, with the pores being dimensioned to allow passage of the first type of suspended particle without distortion or only minimal distortion and passage of the second type of particle only with substantial distortion. Because the filter membrane has precisely dimensioned pores, with spacing between the pores being maintained despite the smaller interval between the pores, the porosity of the membrane may be much greater than nominal pore size membranes, allowing faster filtration rates and/or smaller membranes for a given filtration rate, while reducing the exposure time of the cells within the shear environment, and consequently reducing particle damage. Various methods for preventing clogging of the membrane are also disclosed.

Method and apparatus for filtering suspensions of medical and biological fluids or the like

An apparatus is disclosed for separating a suspension comprising at least two types of particles which are differently sized or shaped and in which the first type of particle may be deformable at a relatively lower force or faster rate than the second type of particle. A housing is provided having a generally cylindrical inner surface in which is mounted a rotor having a generally cylindrical outer surface. The outer surface of the rotor is spaced from the inner surface of the housing to define a suspension processing gap. A filter membrane is provided on the surface of the rotor or the housing that has pores with substantially precisely dimensioned shapes and sizes to correspond substantially to the shape of the first type of particle, thus allowing passage of the first type of particle and blocking passage of the second type of particle. A suspension is directed into the processing gap for either a selected residence time in contact with the filter membrane and/or at a selected force.

Method and apparatus for filtering suspension of medical and biological fluids or the like

The present invention provides an accurate method and apparatus for monitoring the drop flow rate from a fluid source. The drops are indirectly sensed by piezoelectric means mounted on a drip chamber when the drops impinge on a fluid surface in the chamber. The chamber can include a second differential piezoelectric sensing element, which provides a noise reference signal which can be subtracted from the drop sensing signal. The volume of the fluid drops sensed can be determined. The sensing element can be incorporated in open and closed loop disposable chamber modules which can include both monitoring and occlusion valving functions integral therewith.

Indirect piezoelectric drop counter and method

The present invention provides an accurate method and apparatus for sensing and monitoring any buildup in the downline tubing pressure in a fluid infusion system. The initial fluid pressure as indicated by the tubing location is sensed after a delay period and is utilized as a base pressure if it is within allowable limits. The infusion tubing location or pressure is then monitored and compared with the base location or pressure. The system will alarm if a preset differential location or pressure change is exceeded.

Differential occlusion sensing method and apparatus

A system for infusing fluids into the human body includes a peristaltic-type metering apparatus which controls the flow of fluid through a disposable administration set at a preset rate. A compensating circuit within the metering apparatus automatically varies the operating rate of the metering apparatus to compensate for dimensional variations in the apparatus and the tubing.

Metering apparatus having rate compensation circuit

An injection site is provided which is molded inside out with inwardly extending rings. The rings have a smaller internal diameter than the external diameter of the tubular member to which the injection site is to be connected. The injection site has a central portion for receiving a needle therethrough, and a first, cylindrical portion which is extended into the tubular member. After such insertion, the portion with the attached rings is folded back onto the tubular member. The rings become positioned on the outside of the assembly and are in the compressed state squeezing tightly against the tubular member.

Injection site

A gas humidifier set is provided which includes a solution bottle containing a sterile water solution, a cap seal providing a sterile seal for the solution bottle, a connector assembly for penetrating the seal at the time of use and coupling the solution bottle to a gas supply and a covering cap for covering the connector assembly and maintaining it in sterile condition prior to use. The connector assembly includes gas inlet and outlet members. To use the device, the covering cap is removed and the connector assembly is turned thereby causing piercing of the cap seal and communication between the sterile water solution and the gas inlet and outlet members.

Growing community of inventors

Lincolnshire, IL, United States of America

Michael O Pekkarinen