Abstract: A flow-velocity sensor probe includes a thermistor for generating heat which is placed in a fluid, and a waterproof resin and a metal piece for easily radiating the heat generated by the thermistor. The flow velocity of the fluid is measured continuously from a change of temperature in the thermistor, and the thermistor is provided in close proximity to the metal piece for transmitting the heat to the fluid.

Abstract: A multi-luminal catheter is characterized in that the cross-sectional shape of each lumen at a connection portion for an extension tube is molded in accordance with the outer shape of the extension tube to be connected. Accordingly, smooth and hermetic connection between a catheter body and the extension tube, that has not been accomplished in the past, can be obtained, and the formation of steps of the lumen which increases fluid resistance can be prevented. This mult-luminal catheter can be produced by pressing a core metal having substantially the same shape as that of the outer shape of the extension tube into each lumen of the catheter body at the connection portion for the extension tube and inserting the connection portion for the extension tube into a molding die while heating it.

Abstract: A catheter accommodating an electrical wire in the longitudinal direction thereof, wherein an enlargement is provided in at least part of its cavity, and an excess length of wire respect to the catheter in the unstretched state is accommodated slack in the enlargement.

Abstract: An apparatus for measuring cardiac output designed to prevent measurement errors by eliminating the need for a manufacture step of examining a temperature sensing element during manufacture of the same and, hence, the need for a probe circuit or the like which is a means for effecting correction according to the characteristics of the temperature sensing element.

Abstract: A balloon catheter is provided, which comprises a catheter body made of a flexible tube provided with at least one inner channel and with an annular groove formed on an outer surface near the distal end portion of the tube, and a balloon covering the annular groove in such a manner that the outer diameter of the balloon is equal to or smaller than a maximum diameter of the distal end portion of the tube, the balloon being expanded or shrunk through another inner channel. A method of manufacturing the balloon catheter which comprises the steps of reducnig an outer diameter of a distal end portion of the catheter body while keeping a desired inner channel undamaged, mounting a tubular heat-resistant member to a prospective balloon mounting portion of the reduced diameter portion, molding a reduced diameter portion extruded from the heat-resistant member into a spherical shape, and mounting an inflatable balloon to the balloon mounting portion after removing the heat-resistant member.

Abstract: A multi-luminal catheter of this invention is characterized in that the cross-sectional shape of each lumen at a connection portion for an extension tube is molded in accordance with the outer shape of the extension tube to be connected. Accordingly, smooth and hermetic connection between a catheter body and the extension tube, that has not been accomplished in the past, can be obtained, and the formation of steps of the lumen which increases fluid resistance can be prevented. This multi-luminal catheter can be produced by pressing a core metal having substantially the same shape as that of the outer shape of the extension tube into each lumen of the catheter body at the connection portion for the extension tube and inserting the connection portion for the extension tube into a molding die while heating it.

Abstract: Disclosed are a cardiac output measurement method and a system for the application of the same, which perform the calibration of cardiac output by employing a blood flow velocity measurement method and perform continuous measurement of cardiac output. The system includes a blood temperature sensing element for sensing blood temperature, a blood temperature measurement circuit for generating a blood temperature signal indicative of the sensed blood temperature, an equilibrium temperature obtaining element capable of sensing cooling temperature of blood flow being heated, and an equilibrium temperature measurement circuit for generating an equilibrium temperature signal indicative of the sensed cooling temperature of blood flow heated.