Abstract: A portable osmotic pump, having two pouches (4,3) in pressure-transmitting relationship, the first (4) containing a pumped fluid, such as infusate (5), and the second (3), a driving fluid (36). The driving fluid is created and pressurized by activation of an osmotic pump, and the rate of infusion is controlled by a semipermeable membrane (10). Activation can be by rupturing a seal (11) or by opening a closed tube (58) to permit permeant (2) to contact the semipermeable membrane. Pulses of the pumped fluid can be achieved by delivery pulses of the permeant to the second pouch. The pouches can be designed to resist collapse of the first pouch by external forces on the pumped liquid, such as gravity, movement of the first pouch and negative pressures applied to the pumped liquid. The infusate pouch is manufactured separately and can be stored apart from the rest of the system.

Abstract: An apparatus and method for detecting pressure and occlusion in a fluid line is for use with a fluid line being operated upon by a positive displacement, peristaltic pump having several cam follower fingers pressing against the fluid line fluid through the line peristaltically. A sensor follower finger is mounted to the cam shaft of the pump among the other peristaltic fingers in order to cyclicly press against the fluid line and displace the fluid line by a predetermined amount as the cam shaft rotates. The sensor follower finger includes a strain gauge mounted on the sensor finger to generate a signal indicating the degree of force being applied by the sensor finger against the tubing, and a signal processor which receives this force signal and determines the pressure within the fluid line based upon the signal. The signal processor determines the existence of an occlusion based on the signal and provides an alarm if an occlusion is determined.

Abstract: The negative pressure monitor is intended for use in combination with an IV administration set, for monitoring venous, arterial and other physiological pressure signals. The system provides a coupling mechanism with a sealed vacuum chamber between a fluid chamber in communication with the fluid in line, and the pressure transducer. The vacuum in the coupling mechanism serves not only to communicate pressure changes within the fluid chamber to the pressure transducer, but also functions to maintain the fluid chamber in pressure communication with the pressure transducer.

Abstract: Adhesion of a liquid sample is accomplished by drawing same into a capillary tube, followed by forming an immiscible fluid column at each end of the liquid sample in the tube, pulsing the liquid sample between the fluid columns and determining the portion of the liquid sample which adheres to the tube surface. The procedure may be employed for measuring platelet adhesion for a blood sample.

Abstract: A chamber of a peristaltic pump is described wherein a segment of the stator is removed so that said chamber containing the rotor and resilient tube may be stored with the resilient tube not pinched by the eccentric rotor. When the chamber is to be used, a cap is snapped over the chamber which completes the missing segment of the stator and the rotor is engaged to the motor shaft. When the rotor turns in the stator with all segments snapped together, liquid is conducted from inlet to outlet ports.

Abstract: A material is stirred in a container without contact with the container walls by suspending and stirring the material in a vortex generated in a liquid in the container which liquid is immiscible with and has a density greater than the material.