Methods and devices for accurately pumping small quantities of liquid to a patient with a broad range of flow and low cost.

Systems, methods, and apparatuses for regulating the delivery of negative-pressure therapy are described. The system includes a negative-pressure source, an energy source, and a switch. The switch can include a first conductor electrically coupled to the negative-pressure source, a second conductor electrically coupled to the energy source, and a diaphragm having a first position electrically coupling the first conductor to the second conductor and a second position separated from the first conductor and the second conductor. The diaphragm is configured to move between the first position and the second position in response to a differential between a control pressure and a therapy pressure.

A check valve assembly is configured to couple to a first container that retains a first fluid and a second container that retains a second fluid. The check valve includes a fluid inlet housing including a first fluid inlet port defining a first fluid inlet channel, and a second fluid inlet port defining a second fluid inlet channel. A fluid outlet housing is coupled to the fluid inlet housing. The fluid outlet housing includes a fluid outlet port defining a fluid outlet channel. A first diaphragm is seated over the first fluid inlet channel. At least a portion of the first diaphragm is configured to unseat over the first fluid inlet channel to allow the first fluid to pass from the first fluid inlet channel into the fluid outlet channel. A second diaphragm is seated over the second fluid inlet channel. At least a portion of the second diaphragm is configured to unseat over the first fluid inlet channel to allow the second fluid to pass from the second fluid inlet channel into the fluid outlet channel.

A valve with an internal member is disclosed which allows exhaled carbon dioxide to escape from a breathing circuit when the circuit gas pressure drops below a threshold pressure. The valve operates by occluding one or more ports under a relatively high pressure and opening the one or more ports under a relatively low pressure. The internal member is attached to the body of the valve at two or more locations on the internal member. The internal member moves in a direction perpendicular to the gas flow through the valve.

Fluid connector systems including first and second connector portions couplable together to form a fluid pathway therethrough, and can resist fluid flow through the connector when the connector portions are separated from each other. A connector portion can include a connector housing, a luer portion, and a deformable valve member. The deformable valve member is disposed within the connector housing and includes a spherical portion extending partially through a valve opening of the connector housing. The spherical portion defines a slit, and the deformable valve member is configured to selectively prevent fluid flow from the housing volume through the valve opening and to deform to expand the slit and permit fluid flow from the housing volume through the valve opening.

A check valve, including a valve and a valve support surface, to permit a fluid to move through the check valve in a first direction and resist a fluid flow through the valve in a second direction, the valve having a valve diaphragm and an isolating bridge, with a portion of the valve engaging against valve support surface to resist deformation or stretching of the valve when a backflow of fluid into the check valve occurs. The valve support surface having a first surface portion and a second surface portion, and the valve positioned with the valve diaphragm spaced apart from the first surface portion, and the isolating bridge spaced apart from the second surface portion.

A flow regulator for a blood collection assembly includes a housing having an inlet and an outlet, which defines an interior space between the inlet and the outlet. A membrane having a first surface and a second surface is disposed at least partially within the interior space. The membrane has a first position where a flow path between the inlet and the outlet is substantially open, and a second position where the flow path between the inlet and the outlet is at least partially restricted. The membrane is configured to move between the first and second positions in response to a pressure differential acting on the membrane.

The anti-back-flow devices and methods prevent fluid from leaking proximally from a catheter, but allow ready access to the catheter using any male luer device. The devices include proximal surfaces that urge open a valve in response to force from a male luer tip. The valves are associated a female luer hub and adapted to function with standard and typical non-standard male luer fittings.

A pressure compensation valve for a dialysis machine is disclosed. The pressure compensation valve has a valve housing, in which a flow path with fresh dialysate is separated from a flow path with exhausted dialysate by a diaphragm. The diaphragm and the valve housing are configured such that pressure compensation is possible. In addition, the diaphragm is configured such that no vibrations or a reduced amount of vibrations and/or no noise emission or a reduced amount of noise emission will occur during operation. Furthermore, a dialysis machine comprising such a pressure compensation valve is disclosed. The dialysis machine comprises a balancing unit, and the pressure compensation valve is arranged on the outlet side of the balancing unit.

A sheath introducer system including a sheath introducer defining a lumen therethrough and having a proximal valve housing in fluid communication with a distal tubular sheath, wherein a proximal end of the valve housing defines a proximal opening of the lumen of the sheath introducer. A gasket seated within the valve housing has a first surface, a second surface and an outer periphery extending between the first and second surfaces. A first slit is formed into the first surface having an inner surface defining a first gap. A second slit formed into the second surface having an inner surface defining a second gap. A notch extends into the first gap of the first slit forming a bump on the inner surface of the first slit, wherein the second slit intersects the first slit at the notch such that the notch prevents the first and second slits from being in fluid communication.