Abstract: This invention relates to an improved guarded surgical scalpel having a movable guard that can be retracted to expose the blade and that can be extended to cover the sharp cutting edge of the blade. The guard is telescopically mounted inside the blade handle and includes a deflectable top wall portion that holds a detent pin. This detent pin engages a slot having upturned ends that is formed in at least one side wall of the blade handle. The detent pin is biased upwardly into the upturned ends to hold the guard in the retracted or extended position.

Abstract: A needle and a cover with a needle having an elongate shank and a tip with a sharpened point. The cover is coaxially associated with the elongate shank for movement therealong toward the tip and includes a part for extending beyond the sharpened point when the cover is positioned near the tip. A lock associated with the needle and cover cooperates with and holds the cover to prevent axial movement relative to the needle tip after positioning the cover near the tip. A retaining member on the adapter and on the cover releasably attach the cover to the adapter while on the elongate shank of the needle allowing the needle and cover to be disengaged from the catheter and adapter after placement.

Abstract: This invention relates to a process of making a shaped tip on a catheter. In this process, a lubricant solution is placed on a catheter, the catheter is placed on a mandrel, the catheter is heated, and the mandrel is engaged with a die to form a shaped tip on the catheter. The tipping lubricant of this invention comprises water as the solvent. The lubricant is a silicone surfactant, which is non-ionic and which is a good lubricating fluid. The lubricant solution into which the catheter is dipped includes low percentages of a solution stabilizer and an antimicrobial agent to clarify the solution and to inhibit microbial growth in the water solution. Vitamin E or its derivative may also be used in the lubrication solution.

Abstract: A needle point guard assembly includes inner and outer housings disposed in nested relationship to one another to permit relative rotation therebetween. The proximal end walls of the inner and outer housings have apertures each of which is dimensioned to slidably receive a needle. The apertures are disposed in the housings such that they are registered in one rotational orientation of the housings relative to one another to define a first opening that allows a needle to pass therethrough. The needle point guard assembly further includes a spring for rotatably driving the housings relative to one another and a trigger for selectively holding the inner housing with respect to the outer housing in a rotational orientation where the apertures define the first opening. The trigger moves out of interfering relationship between the inner housing and the outer housing when the sharp distal tip of the needle is withdrawn into the needle point guard assembly.

Abstract: A needle point guard having a movable collet to lock the needle in place in the shielded position is provided. The needle point guard of this invention includes a housing, a collet, a rotary ram, a threaded cam fixed to the rotary ram, a spring disposed between the rotary ram and the housing and a trigger catch to hold the threaded cam in place against the force of the spring. The spring is wound when the needle is in the unshielded position. When the needle is withdrawn into the needle point guard, the trigger catch pivots to allow the spring to rotate the threaded cam. This rotation is translated into axial motion by the treads on the threaded cam and threads formed on the inside of the housing. This axial motion forces an annular flange on the collet to bite down on the needle, to thus hold the needle in place in the shielded position.

Abstract: Leakage of blood from the insertion set, during and after safety-needle retraction, is suppressed by components that receive and retain flash blood for viewing--notwithstanding forces developed within the device in retraction. One preferred such system includes a flash chamber that moves with the retracting needle, within a hollow handle, carrying a relatively high flow-impedance element which allows air exhaust from the chamber into the handle to admit flash blood--but isolates blood in the chamber from retraction-generated increase in air pressure in the handle. Energy-absorbing components control or compensate for retraction speed, to provide quiet smooth retraction--while yet enabling use of ample retraction force to make retraction reliable. Among several energy absorbing systems disclosed is a preferred one that includes a viscous material introduced within the hollow handle to damp the retracting motion; and an injection port to facilitate introduction of the viscous material.

Abstract: An interface circuit for interfacing a semiconductor transducer sensor to a patient vital signs monitor is disclosed. In one embodiment, the interface circuit includes a power supply circuit that receives an excitation power signal generated by the patient monitor, and derives therefrom unregulated and regulated supply voltages for use by the electrical components on the interface circuit. Also generated by the power supply circuit is an appropriate sensor excitation signal for the semiconductor transducer. In another embodiment, the interface circuit further includes receiving circuitry for receiving a sensor output signal generated by the transducer sensor. A scaling circuit then scales that signal into a parameter signal that is proportional to the physiological condition detected by the sensor, and that is also proportional to the excitation power signal generated by the patient monitor.

Abstract: A needle and a cover with a needle having an elongate shank and a tip with a sharpened point. The cover is coaxially associated with the elongate shank for movement therealong toward the tip and includes a part for extending beyond the sharpened point when the cover is positioned near the tip. A lock associated with the needle and cover cooperates and holds the cover to prevent axially movement relative to the needle tip after positioning the cover near the tip. The needle and cover may be a part of a catheter assembly having a catheter and an adapter connected to one another for fluid communication and carried coaxially about the needle and hub. The catheter has a bore therethrough sized to surround the elongate shank for movement therewith during insertion and therealong during placement.

Abstract: This invention is an improved flashback vent. A thin piece of biocompatible material is affixed over the open proximal end of a flashback chamber or a plug in the flashback chamber. This material has a plurality of holes formed therein. Thus, where the flashback chamber is used with an IV catheter introducer needle, blood can enter the flashback chamber and allow air to be vented therefrom without blood leaking from the flashback chamber.

Abstract: A safety stop push button mechanism is disclosed that prevents unwanted activation of the push button. The safety stop push button has particular applicability to a catheter and spring activated safety introducer needle assembly. A projection extending from the activation latch engages the catheter hub to prevent inadvertent activation of the safety mechanism until the catheter has been at least partially advanced distally over the needle.

Abstract: An elastic plug assembly is provided for selective penetration by a needle. The elastic plug assembly comprises an elastic plug that is retained in a radially compressed state by a rigid plug retainer. The combined elastic plug and rigid plug retainer may be secured in a housing formed from an elastomeric material. The elastic plug may be penetrated by a needle. Upon removal of the needle, the radially compressed elastic plug will be urged toward its compressed condition with the space that had been occupied by the needle being completely filled to effectively achieve the sealing function of the plug. Needles may repeatedly be penetrated through the plug and removed as necessary, and the plug will efficiently return to its substantially solid sealed state after each successive needle removal.

Abstract: A surgical needle is disclosed which is made up of two concentric tubes. The inner tube has a sharp tip like a conventional hypodermic or intravenous needle. The inner tube can be retracted into the outer tube after use. In one embodiment, the needle forms part of a catheter assembly. A catheter is mounted coaxially around the both tubes. The inner tube has a latching member attached to the end without the sharp tip. The latching member engages detents on a housing to hold the sharp tip in an extended position or a retracted position. The latching member is provided with a porous plug to assist in venting gases during catheter introduction.

Abstract: A filter for rezeroing an in-vivo pressure sensor is disclosed. The filter operates in a signal mode and a rezero mode. In the signal mode, the filter is a low pass filter which filters out noise. In the rezero mode, the filter is a low pass filter which filters out the dynamic components of an in-vivo pressure signal caused by the rezeroing of the pressure sensor. The filter is switchable between the signal and rezero modes. The filter is implemented by means of an active two pole RC filter with a Butterworth response. A circuit is provided to shorten the time in which the filter reaches its final response characteristic. Also disclosed is a method for processing an output from an in vivo pressure transducer, the output signal comprising noise, a mean pressure signal and a dynamic pressure signal.

Abstract: A surgical scalpel having a handle with a blade carrying carriage that can be slid from an intermediate position where the blade is within the handle to an extended position where the blade extends beyond the distal end of the handle and is exposed for use. After use, the blade can then be slid back to the intermediate position to cover the blade when being passed between operating room personnel or can be slid to a permanently locked position where the blade is permanently covered permitting the scalpel to be disposed of. In addition, means are provided for securely latching the blade in the extended position and the intermediate position to prevent inadvertent movement of the blade and means are provided for indicating that the blade is in the permanently locked position for disposal.

Abstract: A combination surgical blade holder allows simple insertion sequentially of a plurality of blades, each blade having an opening for receiving a cleat and/or an abutment in a blade receiving area on the holder. The holder includes a fixed portion and a rotatable portion that pivot relative to one another in the same longitudinal plane around a pivot point positioned adjacent the blade receiving area and lock together to securely hold the blade in the blade receiving area. While the fixed portion of the holder is gripped in one hand, the thumb or finger of the same hand is used to unlock and rotate the rotatable portion to release and eject the blade singlehandedly, without touching the blade. The fixed portion of the holder includes a cleat and/or an abutment that mate with an opening in the blade. Alternatively, the blade includes a tab that mates with a depression in the blade receiving area to lock the blade in the holder.

Abstract: A winged catheter introducer is disclosed. The catheter introducer has a catheter, a robe attached to the catheter and a winged intermediate member between the catheter and the robe. Within the catheter and the robe is a needle with a stylet attached to it. The stylet is attached to a hub which facilitates the pulling of the needle out of the catheter and through the robe. Attached to the robe is an adapter with a septum attached to it. The needle is provided with an opening extending from the needle wall to the needle lumen. A shielding device is provided which is attached to the adapter. The shielding device includes a needle container which is designed to trap the needle. A needle shield is provided inside the needle container. The needle is provided with an area of enlarged diameter. This area of enlarged diameter interacts with the needle shield when the needle is withdrawn from the catheter and robe and into the needle container.