Patent ID: 12245841

DETAILED DESCRIPTION OF THE INVENTION

The presently preferred embodiments of the described invention will be best understood by reference to the Figures, wherein like parts are designated by like numerals throughout. It will be readily understood that the components of the present invention, as generally described and illustrated in the Figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the cannula locator device, cannula locator system, and associated methods, as represented inFIGS.1through8, is not intended to limit the scope of the invention, as claimed, but is merely representative of some embodiments of the invention.

Generally, this application relates to optical fiber sensors. In particular, the present disclosure relates to devices, systems, and associated methods to detect a position of a cannula and/or a catheter tube using an optical fiber sensor. Detecting the position of a distal tip of the cannula and/or the catheter tube may allow a clinician to appropriately position the distal tip of the cannula during a medical procedure, such as, for example, an intravenous infusion, blood draw, spinal tap, or epidural.

FIGS.1A-1Bare cross-sectional views of a portion of an optical fiber10disposed within a cannula12, according to some embodiments. In some embodiments, the cannula may include a distal tip14, an elongated tubular shaft16, and an inner lumen18formed by the elongated tubular shaft16. In some embodiments, the optical fiber10may be disposed within the inner lumen18of the cannula12. In some embodiments, the optical fiber10may include a first end20, a second end22, and a U-shaped portion24disposed between the first end20and the second end22. In some embodiments, the U-shaped portion24may be disposed at least proximate the distal tip14. In some embodiments, the first end20of the optical fiber10may be coupled with a light emitter (not illustrated inFIGS.1A-1B). In some embodiments, the second end22of the optical fiber10may be coupled with a light receiver (not illustrated inFIGS.1A-1B). One of ordinary skill in the art will appreciate that the first end20may be coupled with the light receiver, and the second end22may be coupled with the light emitter, in some embodiments.

In some embodiments, a decrease in an intensity of light received at the light receiver may occur in response to the optical fiber10contacting blood or another medium when distal tip14of the cannula12is inserted into the blood vessel. For example, the light emitter may emit light, which may be transmitted from the first end20to the second end22of the optical fiber. The intensity of light received at the light receiver may be monitored by an electronic processor (not illustrated inFIGS.1A-1B). In some embodiments, when the distal tip14of the cannula12enters the blood vessel, blood within the blood vessel may travel into the distal tip14and contact the optical fiber10, which may result in an increase in light lost from the optical fiber10due to refraction. In further detail, as illustrated inFIG.1A, before the optical fiber10contacts blood, the optical fiber10may contact air or another medium inside the cannula12, which may have a lower refractive index than blood. Before the optical fiber10contacts blood, total internal reflection or increased internal reflection may occur as light is transmitted through the optical fiber. Because a refractive index of blood may be higher than a refractive index of air and closer than the refractive index of air to a refractive index of the optical fiber10, when blood contacts the optical fiber10, as illustrated inFIG.1B, more light may be lost from the optical fiber10due to refraction and the optical fiber10may become less efficient. Thus, less light may return to the light detector than in an absence of blood.

In some embodiments, the optical fiber10may be configured to contact blood when the cannula12is inserted in the blood vessel. In particular, in some embodiments, the U-shaped portion24of the optical fiber may be configured to contact blood first when the cannula12is inserted in the blood vessel. In some embodiments, prior to insertion of the cannula12in the blood vessel, all or a portion of the optical fiber10may contact air. In some embodiments, when the cannula12is inserted into the blood vessel, blood may surround or immerse the optical fiber10. In some embodiments, the U-shaped portion24may be disposed at least proximate the distal tip14of the cannula12. In some embodiments, a distal most portion of the U-shaped portion24may be disposed proximal to a beveled edge26of the distal tip14, which may increase a likelihood that the beveled edge26is fully inserted in the blood vessel when the decrease in the intensity of light is detected and/or protect the optical fiber as the cannula12is inserted through the skin, fat, tissue, etc. of the patient.

In some embodiments, the optical fiber10may be a homogeneous optical fiber. In these and other embodiments, the optical fiber10may be without cladding so as to let light escape axially from the optical fiber10, which may facilitate measurement of the decrease in the intensity of light when the optical fiber10is exposed to blood.

In some embodiments, the optical fiber10may be planar, as illustrated inFIGS.1A-1B. In further detail, in some embodiments, the U-shaped portion24, the first end20, and the second end22may be disposed within a same plane. In some embodiments, the first end20and the second end22may be parallel to each other, as illustrated inFIGS.1A-1B.

Referring now toFIGS.2A-2B, in some embodiments, the first end20and the second end22may be twisted with respect to each other. For example, the first end20and the second end22may be twisted with respect to each other one, two, three, or more times to form a helical shape. The first end20and the second end22may be twisted with respect to each other to form a crossing portion23at which the optical fiber10crosses itself. The optical fiber10may include two opposing portions25a,25bbetween the U-shaped portion24and the crossing portion23. The two opposing portions25a,25bmay be spaced apart by a portion27of the inner lumen18.FIG.2Aillustrates the first end20and the second end22twisted with respect to each other one time to form the helical shape.FIG.2Billustrates the first end20and the second end22twisted with respect to each other two times to form the helical shape. The helical shape of the optical fiber10may increase a length and surface area of the sensitive section of the optical fiber10that contacts blood, which may result in increased or continuous loss of light as light is transmitted through the optical fiber10in contact with blood as blood flows in the proximal direction within the cannula12. Thus, the helical shape may provide an improved or continuous indication of the location or position of the cannula12.

For example, when a medium contacting the optical fiber10changes from a first medium, for example air, to a second medium, for example blood, a loss in the intensity of light received by the light receiver may occur. A contact area between the optical fiber10and the second medium may increase due to the helical shape, and the loss in the intensity of light may occur along the contact area. If the first medium and the second medium have similar refractive indexes, a movement from the first medium to the second medium may be more easily detected when the optical fiber includes the helical shape. The first end20and/or the second end22may be bent and/or twisted in any number of ways that may serve to increase the surface area of the optical fiber10that contacts blood.

The cannula12may include any cannula that may be used with the optical fiber10described in the present disclosure, including, but not limited to, a hypodermic needle, such as an intravenous catheter (IV) introducer needle, a peripheral intravenous catheter (PIVC) introducer needle, an epidural introducer needle, a spinal tap needle, etc.

Referring now toFIG.3, in some embodiments, a system28may include an optical fiber sensor device29. In some embodiments, the optical fiber sensor device29may include the cannula12and/or the optical fiber10. The optical fiber sensor device29may correspond to any number of devices that include the optical fiber10. In some embodiments, the optical fiber sensor device29may include a catheter device, as will be discussed further with respect toFIG.4. In some embodiments, the system28may include a light emitter30, which may be coupled with the first end20of the optical fiber10. In some embodiments, the system28may include a light receiver32, which may be coupled with the second end22of the optical fiber10. In some embodiments, the light receiver32may be configured to convert light into an electrical signal.

In some embodiments, the system28may also include an electronic processor34, which may be coupled with the light receiver32. In some embodiments, the electronic processor34may be configured to receive the electrical signal from the light receiver32and monitor an intensity of light received at the light receiver32. In some embodiments, the electronic processor34may be configured to detect a change in the intensity of light received at the light receiver32based on the electrical signal. In particular, in some embodiments, the electronic processor34may be configured to detect the decrease in the intensity of light received at the light receiver32, which may occur in response to the optical fiber10contacting blood, for example.

In some embodiments, the system28may include an alarm36. In some embodiments, the electronic processor34may be configured to initiate the alarm36, which may produce an audible sound, a flashing light, etc. In some embodiments, the electronic processor34may initiate the alarm in response to the electronic processor34detecting the decrease in the intensity of the light received at the light receiver32. In some embodiments, the alarm36may be configured to sound in response to the detection of the decrease in the intensity of the light received at the light receiver32.

In some embodiments, the alarm36may be reusable. In some embodiments, a monitoring unit38may include one or more the following: the light emitter30, the light receiver32, the electronic processor34, and the alarm36. In some embodiments, one or more of the following elements may be selectively coupled to the optical fiber10: the light emitter30, the light receiver32, the electronic processor34, the alarm36, and the monitoring unit38. In some embodiments, an optical connector40may selectively couple the optical fiber10to one or more of the elements. Thus, one or more of the elements may be uncoupled from the optical fiber10via the optical connector4, and the optical fiber10, the cannula12, and/or the optical fiber sensor device29may be disposed of while the one or more elements may be reusable. In some embodiments, the first end20and the second end22may be coupled with a proximal end of the optical connector40, as illustrated inFIG.3. In some embodiments, the light emitter30may be coupled with the first end20and/or the light receiver32may be coupled with the second end22via the optical connector40.

The optical connector40may be disposed in any number of locations. In some embodiments, the optical connector40may be disposed at a proximal end of the optical fiber sensor device29that includes the cannula12. In these and other embodiments, the optical connector40may be disposed within the optical fiber sensor device29. In some embodiments, the optical connector40may be eliminated and the optical fiber sensor device29may be directly coupled to the monitoring unit.

Referring now toFIG.4, in some embodiments, the optical fiber sensor device29may include or correspond to a catheter device42, an example of which is illustrated inFIG.4. The catheter device42may include any number of catheter devices. Exemplary catheter devices may include both straight and ported intravenous catheter devices, such as the AUTOGUARD™ shielded catheter device commercially available from Becton, Dickinson, and Company, integrated peripheral intravenous catheter devices, winged catheter devices, catheter devices with safety mechanisms, catheter devices with needle shields, blood collection sets, IV access sets such as the BD NEXIVA™ Closed Intravenous (IV) Catheter system available from Becton, Dickinson, and Company, etc.

In some embodiments, the catheter device42may include a catheter adapter44having a catheter tube46. In some embodiments, the cannula12of the catheter device42may include an introducer needle. In some embodiments, the catheter device42may include a needle hub48, which may be coupled with a proximal end50of the cannula12. In some embodiments, the needle hub48may be coupled with the catheter adapter44. In some embodiments, the first end20and the second end22of the optical fiber10may extend through all or a portion of the catheter device42, as illustrated inFIG.4.

In some instances, because the catheter tube46may be proximal to the distal tip14of the cannula12when the cannula12is inserted in the blood vessel of the patient, the catheter tube46may still be outside the blood vessel when the cannula12is within the blood vessel. Referring now toFIG.5, in some embodiments, the optical fiber10may be disposed within an outer wall of the catheter tube46such that the optical fiber10contacts blood when the catheter tube46is inserted in the blood vessel of the patient. Thus, the optical fiber10may improve detection of a position of the catheter tube46.

The optical fiber10may be disposed within the outer wall of the catheter tube46in any number of ways. For example, the optical fiber10may be inserted, molded, or co-extruded into the catheter tube46. In some embodiments, the optical fiber10may extend to a distal tapered portion of the catheter tube46and/or may be planar, as illustrated inFIG.5. In some embodiments, the optical fiber10may extend to a distal edge of the catheter tube46.

In some embodiments, the optical fiber10may be disposed within an inner wall of the catheter tube46or another portion of the catheter device42(not illustrated inFIG.5). The optical fiber10may be disposed within the inner wall in any number of ways. For example, the optical fiber10may be inserted, molded, or co-extruded into the inner wall. In some embodiments, the cannula12may include a notch feature, which may define an opening in the elongated shaft16(not illustrated inFIG.5). In some embodiments, the notch feature may be configured to allow blood to flow between the distal tip14and the notch feature. In some embodiments, the blood may then flow out of the notch feature and into a portion of the catheter device, such as the catheter tube46and/or a body of the catheter adapter44, where the blood may contact the optical fiber10disposed within the inner wall.

The optical fiber10illustrated inFIG.5may include or correspond to the optical fiber10described in the previous figures. For example, in some embodiments, the first end20and the second end22of the optical fiber10may be twisted with respect to each other.

FIG.6illustrates a block diagram of an example method100to detect the position of the cannula12and/or a catheter tube46, according to some embodiments. The method100may begin at block102in which the cannula12and/or the catheter tube46is provided. In some embodiments, the cannula12may include the distal tip14, the elongated tubular shaft16, and the inner lumen18formed by the elongated tubular shaft16. Block102may be followed by block104.

At block104, the optical fiber10may be provided. The optical fiber10may be disposed within the inner lumen18of the cannula12, the outer wall of the catheter tube46, and/or the inner wall of the catheter tube46. In some embodiments, the optical fiber may include the first end20, the second end22, and the U-shaped portion24disposed between the first end20and the second end22. In some embodiments, the optical fiber10may be disposed at least proximate the distal tip14. Block104may be followed by block106.

At block106, the light emitter30may be provided. Block106may be followed by block108.

At block108, the light receiver32may be provided. In some embodiments, the light receiver32may be coupled with the second end22of the optical fiber10. In some embodiments, the light receiver32may be configured to convert light into an electrical signal. Block108may be followed by block110. Block108may be followed by block110.

At block110, the electronic processor34may be provided. In some embodiments, the electronic processor34may be coupled with the light receiver32. Block110may be followed by block112.

At block112, an intensity of the light received at the light receiver may be detected.

Although illustrated as discrete blocks, various blocks may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. In some embodiments, the method100may include additional blocks. For example, in some embodiments, the method100may include inserting the cannula12into a blood vessel and detecting the decrease in the intensity of light received at the light receiver32, which may occur in response to the optical fiber10contacting blood in the blood vessel. As another example, in some embodiments, the method100may include sounding the alarm36in response to detecting the decrease in the intensity of the light received at the light receiver32.

In addition to the previously described embodiments of the optical fiber10, the optical fiber10may be modified in any suitable manner that allows it to fulfill its intended purpose. Further, the optical fiber10may be used in any suitable manner. Also, in addition to the previously described embodiments of the system28, the system28may be modified in any suitable manner that allows it to fulfill its intended purpose. By way of non-limiting illustration, the system28may not include the alarm36. Further, in addition to the previously described embodiments of the catheter device42, the catheter device42may be modified in any suitable manner that allows it to fulfill its intended purpose.

The present invention may be embodied in other specific forms without departing from its structures, methods, or other essential characteristics as broadly described herein and claimed hereinafter. The described embodiments and examples are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.