WO1992019161A1

WO1992019161A1 - Vascular probe

Info

Publication number: WO1992019161A1
Application number: PCT/US1992/000800
Authority: WO
Inventors: Francis Robicsek
Original assignee: Bio Vascular Inc
Current assignee: Bio Vascular Inc
Priority date: 1991-04-30
Filing date: 1992-01-31
Publication date: 1992-11-12
Anticipated expiration: 1993-10-30

Abstract

A vascular probe (10) having a flexible stem (12) and a pair of bulbous tips (14, 16), one at each end of the stem, is disclosed. According to one embodiment of the present invention, there is provided a combined vascular probe and retractror. This combination probe and retractor can be inserted within the vascular system by cardiac, vascular and cardiovascular surgeons during a cardiac or a vascular surgical procedure. It is used to calibrate blood vessels, occlude bloods vessels, and identify stenotic lesions remote from the site of an anastomosis. The device features a disposable, flexible polyurethane coated acrylic shaft having a calibrated occluder bulb at each end, although other base materials such as radiopaque metal are useful. It is coated with a material such as polyurethane to reduce friction upon contact with a vessel wall and is available in a variety of tip sizes.

Description

VASCULAR PROBE

BACKGROUND OF THE INVENTION

I. Field of the Invention

This invention relates generally to the design of surgical instruments and devices and more particularly to a combination vascular probe and retractor. This vascular probe is inserted within the vascular system by cardiac, vascular and cardiovascular surgeons during cardiac or vascular surgery. It is used for medical procedures such as calibrating blood vessels, occluding blood vessels, and identifying stenotic lesions remote from the site of an anastomosis, among others.

II. Description of the Prior Art

Surgical instruments for the separation or obturation of tissue or ducts typically feature a generally blunt or conical tip, often mounted on a shaft, and generally having a discrete handle portion for grasping by the surgeon.

U.S. Patent 4,959,067, issued on September 25, 1990 to George H. Muller, for example, discloses a tissue separating bulbous tip on a flexible stem. This device is intended for use in separating tissue and features a straight, elongated shaft having a handle portion at one end. An associated flexible stem extending from this shaft provides controlled flexibility. The stem terminates in a spherical tip which is designed to snap onto the end of the stem and held there by an adhesive. Alternatively, this stem and tip may be integrally molded. The handle and tips are preferably luminescent and colored to provide a visual indication of their positions when submerged in tissue.

U.S. Patent No. 4,168,708, issued to Lepley, Jr., et al. on September 25, 1979, discloses a T-shaped blood vessel occluder suitable for use in anastomosis procedures. The device has a main stem with a bar at one end. The bar is formed by a pair of opposing arms. A solid bulb is positioned at each end of the bar. The bulbs are generally conical or bullet shaped and are intended to be inserted within a coronary artery through an incision made at the location where a bypass graft is to be affixed. In use, an incision is prepared in the wall of a blood vessel which is approximately equivalent in length to one arm of the bar. This arm is urged along inside the vessel until the main stem contacts the edge of the incision. The other bulb is then urged into the vessel. The device is thus positioned to block the flow of blood to the anastomosis site. The graft is then sutured into place, the occluder being removed just prior to final suturing of the graft. U.S. Patent No. 3,366,927, issued to Gerald Klebanoff on August 22, 1967, discloses a surgical probe for bile duct explorations. The probe includes a filiform which is detachably secured to an olive by a threaded connection. The olive is attached via a flexible shaft to a handle. The handle assists in manipulation within the duct. The device can be formed in a variety of shapes which enable the instrument to be moved axially or rotated about its own axis by the surgeon. This patent also describes alternative olives having either a stone scoop or a scalpel trough.

A duct dilator is disclosed in U.S. Patent No. 3,196,876, issued to Maurice M. Miller on July 27, 1965. This device has two portions, each terminating in a bulbous region. The substantially rigid handle portion is approximately ten inches long, while the attached malleable probe portion is about five inches long. The malleable probe portion terminates in an enlarged oval tip. A sleeve dilator having a central bore extends over the probe portion. The sleeve dilators are dimensioned slightly larger than the diameter of the malleable probe, yet slightly smaller than the diameter of the enlarged oval tip. Thus, the sleeve is pushed down over the handle and progressed forward over the entire length of the malleable probe until its tip reaches and is stopped by the probe's enlarged oval tip. The sleeve dilators are available in a variety of signs wherein the tip end of each is also oval shaped and slightly enlarged. The diameter of the tip of the first sleeve is about one millimeter larger than the diameter of the probe tip. The probe tip is approximately three millimeters in diameter. The various sleeves may thus be progressively introduced until an appropriate dilation is attained.

U.S. Patent No. 2,221,138, issued on November 12, 1940 to F. C. Hendrickson, describes a tapered bougie for exploring and treating strictures. It has a tapered metal core formed of a plurality of fine wires. The number of these wires present within succeeding sections is reduced along the length of the device so as to give it a taper. The tapered wires are comprised of a combination of spring wire and soft annealed wire in order to lend a memory property. This device can be attached to the end of another instrument and used as a dilator.

The use of graduated coronary probes while performing the distal anastomosis of an aorto-coronary bypass procedure is described in "Graduated Probes for Coronary Bypass Surgery" by Victor Parsonnet, Lawrence Gilbert, and Isaac Gielchinsky in the Journal of Thoracic and Cardiovascular Surgery, Vol 68, No. 3, pp. 424-427, September 1974. The probes described in this article are intended as a substitute for prior art coronary dilators. These probes are useful in maintaining accuracy of suture placement, maintenance of a dry operative field (prevent retrograde/antegrade bleeding into an anastomotic site) , calibration of the internal diameter of an artery, localization and calibration of stenotic lesions remote from the anastomotic site, dilatation of stenotic areas, dilatation of the corners of anastomoses, clear identification of the lumen of a vessel, prevention of coronary air embolism, identification of the course of an artery and localization of major tributaries, and avoidance of trauma to an artery by obviating the need for tourniquets or clamps to occlude flow. The probes described have a cylindrical, 45 cm long shaft with a blunt end design for receiving a removable, stainless steel stylet insert at one end and a smooth olive tip at the other end. A selection of sizes is available for the olive tips, graduated in outer diameter from 1.0 to 3.5 mm. The shafts are either 1.0 or 1.55 mm in diameter. They are constructed of a reinforced fiber (Dacron) covered by polyurethane. The tips of these probes are elongated and somewhat pointed. To further avoid trauma to an artery, a tip having a more rounded design is desirable. SUMMARY OF THE INVENTION As indicated above, medical probes of various types are well known in the prior art. However, none of these probes provide a truly effective way to calibrate blood vessels during vascular or cardiac surgical procedures. Similarly, in some situations even very effective probes, like the ones disclosed in the Lepley, Jr. *708 Patent, cannot be conveniently used to occlude the blood vessels. Also, the nature of the handle design in some of these prior art probes makes it difficult to use the probe to discover the exact location of a stenotic lesion remote from an anastomosis site. The present invention was developed to specifically resolve these limitations inherent in prior art probes, as well as provide a low- cost device.

According to one embodiment of the present invention, there is provided a combined vascular probe and retractor. This combination probe and retractor can be inserted within the vascular system by cardiac, vascular and cardiovascular surgeons during a cardiac or a vascular surgical procedure. It is used to calibrate, retract or occlude blood vessels, identify stenotic lesions remote from the site of an anastomosis, and maintain a dry surgical field. The device features a disposable, flexible, coated shaft having a calibrated occluder bulb at each end. It is comprised of a flexible material such as an acrylic substrate and is coated with a material such as polyurethane to reduce friction as it is advanced within the lumen of a blood vessel. It is available in a variety of tip sizes.

It is accordingly a principal object of the present invention to provide a new and improved method and apparatus for calibrating blood vessels during cardiac or vascular surgical procedures. Another object of the present invention is to provide a new and improved method and apparatus for occlusion of blood vessels during such procedures.

It is yet another object of the present invention to provide a new and improved method and apparatus for probing to discover the exact location of stenotic lesions remote from the site of an anastomosis.

A further object of the present invention is to provide a new and improved method and apparatus for such probing within a vessel using a device that is more flexible than those available in the prior art.

A still further object of the present invention is to provide a new and improved method and apparatus for introducing a probe into a vessel that minimizes the size of the hole in a vessel wall required for such procedures and does not require stretching or pulling of the vessel wall to accomplish such introduction.

Yet another object of the present invention is to provide a new and improved method and apparatus which will enable movement of the probe upstream or downstream within a vessel without requiring that the surgeon remove the device and reinsert it through an additional hole in the vessel wall.

Other objects of the present invention and many of its attendant advantages will be more readily appreciated as the invention becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout. DESCRIPTION OF THE DRAWINGS Figure 1 depicts a plan view of a preferred embodiment of the present invention;

Figure 2 depicts an enlarged, partial, side cut-away view of the embodiment of Figure 1; and

Figures 3A, 3B and 3C depict the preferred embodiment in situ.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A preferred embodiment of the combined vascular probe and retractor is shown in Figure 1. Generally depicted as

10, the vascular probe of the present invention features a generally cylindrical shaft 12 having bulbous heads 14 and 16 disposed at opposing ends of the cylindrical shaft 12. The shaft 12 is dimensioned to enable the probe to be bent without breaking and component materials have been selected accordingly, as described more fully hereinafter. The vascular probe 10 is of unitary construction. The components have a base coated with a polyurethane plastic. The polyurethane coating is advantageous to reduce friction between the probe 10 and an internal wall of the vessel being treated. The preferred length of the flexible, cylindrical shaft 12 can vary. A suggested range for the length of the shaft 12 is from approximately 4 cm to 90 cm. Shafts having lengths of 80 mm (3.150") or 45 cm (17") would, for example, be appropriate. The diameter of the shaft preferably falls within a range between 0.5 mm and 1.0 mm.

Each of the bulbous heads 14 and 16 are dimensioned to fit within the vessel in which the device is to be used. Their exteriors are smooth and unencumbered by edges which might tear the vascular wall. A variety of vascular probes 10 having differing head sizes is preferably made available to the surgeon so that the surgeon can select the size best suited for the particular application. Color coding can be used to help the surgeon differentiate between the various sizes offered. An appropriate assortment of probes 10 would include heads 14 and 16 of varying diameters and lengths. Suitable diameters generally fall in the range of 1.0 mm (0.039") to 2.5 mm (0.098"). Suitable lengths generally fall in the range of 3.91 mm (0.154") to 5.36 mm (0.211"). Also, to provide the surgeon with a greater range of options, the vascular probe 10 can be made so that the heads 12 and 14 are of different sizes. This reduces the likelihood of needing to open a second sterilized package containing a probe, due to an inappropriate size selection. Thus, for example, an 80 mm (3.150") shaft 12 may be coupled at one end with a bulb 14 having a diameter of 1.0 mm (0.039") and a length of 3.91 mm (0.154") and coupled at its other end with a bulb having a length of 5.00 mm (0.197") and a diameter of 1.50 mm (0.059"). A similar probe may be fitted at one end with a 2.00 mm (0.079") diameter, 5.00 mm (0.197") length bulb and at the other end with a 2.50 mm (0.098") diameter, and 5.36 mm (0.211") length bulb. As previously stated, the shaft 12 to which these bulbs are attached may be either 80.0 mm (3.150") or 450.0 mm (17.72"). The particular combination of sizes to be used during a procedure is selected on the basis of the internal diameter of the host vessel and the length of shaft required for easy manipulation by the surgeon. An additional feature of the present invention is the inclusion of a marking pattern 18 in the form of a premeasured scale inscribed along the length of the shaft 12. Such a scale provides the surgeon with a means for determining the precise distance from the insertion hole in a vessel wall to either tip of the probe. The marking pattern 18 extends the full length of the shaft 12 from bulbous tip 14 to bulbous tip 16.

Figure 2 shows a partial, enlarged, side cut-away view of the vascular probe of the present invention. This view illustrates the base 20 of the bulb 14 and stem 12. This base 20 may be acrylic or other flexible material, but one of radiopaque material such as titanium, nickel, or any precious metal may be preferred for some applications. A coating such as polyurethane plastic coating 22 provides a smooth, biocompatible surface over the entire probe 10. An example of the preferred coating material is Estane^® Polymer, available from the thermoplastics group of BF Goodrich's Specialty Polymers and Chemical Division, located in Brecksville, Ohio. The Estane^® is particularly desirable for this application, since it has a tensile strength rated at 7300 psi and a Shore hardness of 46D.

Figures 3A, 3B and 3C depict various placements of the vascular probe within a vessel. During a medical procedure, the surgeon grasps the vascular probe 10 along the shaft 12 and inserts the bulb (14 or 16) of choice through an incision 24 that has been prepared in a vessel wall 26. The appropriate bulb size is selected on the basis of the internal diameter of the host vessel. The bulb is urged forward along the interior lumen of the vessel 26. When used as a probe, as in Figure 3A, the shaft 12 is advanced within the vessel lumen until it encounters the resistance of an occlusion 28. Reference to the scale 18 on the shaft 12 gives an indication of the precise distance between the occlusion 26 and the incision 24. It can further be used to determine that a newly formed anastomosis of a bypass vessel 30 is, in fact, distal to the occlusion 28.

The probe 10 can also be used as either a stent or a retractor, as shown in Figure 3B. During the creation of the anastomosis, its bulb 14 may be manipulated to assist in suturing a graft, such as vessel 30, to ensure proper attachment. Flexion of the shaft 12 causes the bulb 14 to exert pressure on the wall of vessel 26. This pressure alters the conformation of the incision 24 by pulling at its edges. The vessel 30, such as the saphenous vein, is then more easily matched to the incision in the vessel 26, such as the coronary artery. Suture material 32 is looped through the adjoining edges of vessels 26 and 30 and pulled taut. Figure 3C depicts the positioning of the probe 10 just prior to completion of the anastomosis and withdrawal of shaft 12 and bulb 14 from the incision 24 in vessel 26 at the point of junction with vessel 30. During this part of the procedure, easy withdrawal of the bulb 14 from the vessel 26 indicates that the distal anastomic lumen is of an appropriate dimension. Double armed suture material 32 is used to close the remainder of the anastomosis after the bulb 14 is withdrawn. Additionally, the bulbs on the probe 10 can be used as vessel occluders. When a sufficiently sized bulb is placed upstream to a surgical site (not shown) , it may totally occlude the lumen of the vessel and thus allow maintenance of a dry surgical field. When similarly placed at the site of a graft then removed, it may be used to confirm the adequacy of a newly created anastomosis. Finally, by testing which bulbous tips may be inserted within the vessel, the bulb may be used to measure the internal diameter of the vessel. Thus, it may be seen that the vascular probe of the present invention may be used for a variety of broad applications, such as vessel occlusion, measurement and retraction, in addition to its utility as a probe.

This invention has been described herein in considerable detail in order to comply with the Patent Statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices and that various modifications, both as to equipment details and operating procedures, can be accomplished without departing from the scope of the invention itself. What is claimed is:

Claims

1. A surgical probe to be inserted through an incision prepared in the wall of a vessel or duct comprising: a bendable stem portion having a first end and a second end; a first smooth bulbous head unencumbered by edges affixed to said first end of said stem; and a second smooth bulbous head unencumbered by edges affixed to said second end of said stem; said stem, said first smooth bulbous head, said second smooth bulbous head all including a base covered by a coating which reduces friction between the probe and the wall of the vessel.

2. The surgical probe of Claim 1, wherein said flexible stem portion has a length falling in a range from 4 cm to 90 cm.

3. The surgical probe of Claim 2, wherein said flexible stem portion has a diameter falling in a range from 0.5 mm to 1.0 mm.

4. The surgical probe of Claim 1, wherein said first smooth bulbous head has a diameter in the range of 1.0 mm through 2.5 mm.

5. The surgical probe of Claim 1, wherein said first smooth bulbous head has a length in the range of 3.91 mm through 5.36 mm.

6. The surgical probe of Claim 1, wherein said second smooth bulbous head has a diameter in the range of 1.0 mm through 2.5 mm.

7. The surgical probe of Claim 1, wherein said second smooth bulbous head has a length in the range of 3.91 mm through 5.36 mm.

8. The surgical probe of Claim 1, wherein said base is acrylic.

9. The surgical probe of Claim 1, wherein said base is a metal.

10. The surgical probe of Claim 9, wherein said metal base is among the group of titanium, nickel and precious metal.

11. The surgical probe of Claim 1, wherein said coating is a polyurethane.

12. The surgical probe of Claim 1, wherein said first and second smooth bulbous heads have different diameters.

13. The surgical probe of Claim 1, wherein said first and second smooth bulbous heads have different lengths.

14. The surgical probe of Claim 1, wherein said shaft is marked with a measuring scale.

15. A surgical probe to be inserted through an incision prepared in the wall of a vessel or duct comprising: a bendable stem portion having a first end and a second end; a first smooth bulbous head unencumbered by edges affixed to said first end of said stem; a second smooth bulbous head unencumbered by edges affixed to said second end of said stem; said stem having a length falling in a range from 4 cm to 90 cm and said first and second smooth bulbous heads each having a length in the range of 3.91 mm to 5.36 mm and a diameter in the range of 1.00 mm to 2.5 mm.

16. The surgical probe of Claim 12, wherein the stem and first and second smooth bulbous heads each have a base covered by a coating which reduces friction between the probe and the wall of the vessel.

17. The surgical probe of Claim 15, wherein said base is acrylic.

18. The surgical probe of Claim 15, wherein said base is a metal.

19. The surgical probe of Claim 18, wherein said metal base is comprised of material from among the group of titanium, nickel and precious metal.

20. The surgical probe of Claim 15, wherein said coating is a polyurethane.

21. The surgical probe of Claim 15, wherein said shaft is marked with a measuring scale.

22. A method of identifying the site of an occlusion in a blood vessel comprising the steps of: cutting an incision into the wall of a blood vessel; introducing a probe through said incision to rest within the lumen of said blood vessel, said probe including a shaft labeled with a measuring scale and having a pair of ends, a first smooth bulbous head attached to one end of the shaft, and a second smooth bulbous head attached to the other end of the shaft; extending said probe through said vessel until movement is arrested by contact of the first smooth bulbous head with said occlusion; and using said measuring scale on said stem of said probe to measure a distance from said incision to said occlusion.

23. A method of occluding blood vessels comprising the steps of: cutting an incision into the wall of a blood vessel; introducing a probe through said incision to rest within said blood vessel, said probe including a shaft having a pair of ends, a first smooth bulbous head attached to one end of the shaft, and a second smooth bulbous head attached to the other end of the shaft; and positioning said probe within said vessel until the passage of blood within said vessel is blocked by at least one of the first and second smooth bulbous heads.

24. A method of calibrating blood vessels through the use of a plurality of probes, each probe having a stem with a smooth bulbous head of a known diameter attached to each end of the stem, said method comprising the steps of: cutting an incision into the wall of a blood vessel; introducing a probe through said incision; and repeating said introduction of such probes having smooth bulbous heads of differing known diameters, if necessary, until a head is introduced which significantly reduces the flow of blood within said vessel.