US3636943A - Ultrasonic cauterization - Google Patents

Abstract

The method and apparatus of the invention use ultrasonic energy in the form of mechanical vibrations transmitted by a tool member to close off small severed blood vessels, such as in humans, by the formation of closures at the terminal portions thereof, and stop what is called ''''ooze,'''' that requires constant mopping or cleansing techniques during an operation. This tool member may be in the form of a knife ultrasonically vibrated to simultaneously sever and close off respective terminal portions of the severed blood vessels while performing surgical procedures. The tool member, of a proper configuration, may also join together layers of tissue, including the walls of unsevered blood vessels, and with respect to the latter is foreseen as replacing the ''''tying off'''' of arteries and veins currently necessary in surgery.

Description

Zg-ZnA AU 335 EX ---wvuvwulyvfl n'atclll Balamuth 1 Jan. 25, 1972 [54] ULTRASONIC CAUTERIZATION 2,730,103 l/l956 Mackta 128/305 2,888,928 6/1959 Seiger ..l28/303.17 [72] Balammh New 3,058,470 10/1962 Seeliger et al..... ..128/303.l7 x [73] Assignee: Ultrasonic Systems, Inc., Farmingdale, 3,086,288 4/1963 Balamuth et a1. ..l28/305 UX NY. 3,308,003 3/1967 Deans v.128/305 X [22] Filed on. 27 1967 3,433,226 3/1969 Boyd ..128/3O5 [21] App]. No.: 678,649 Primary Examiner-Richard C. Pinkham Assistant Examiner-Richard J Apley An -L d W. S ff 52 us. c1. ..l28/24 A, 128/303.17. 128/305, omey 156/73 57 ABSTRACT [51] Int. Cl. ..A6lb17/36, A61b 17/32, A61h 23/00, l [58] Field ofSeaT-ch ..128/2.1,24.05,30313-30319, The method and pp us of t e n ention use ultrasonic 123/305, 24 156/73 energy in the form of mechanical vibrations transmitted by a I tool member to close off small severed blood vessels, such as [56] Rd Cit d in humans, by the formation of closures at the terminal portions thereof, and stop what is called ooze," that requires UNITED STATES PATENTS constant mopping or cleansing techniques during an opera- 2 985 954 5/1961 Jones at al 156/73 UX tion. This tool member may be in the form ofaknife ultrasonil4 2/1962 Bodine Jr 156/73 cally vibrated to simultaneously sever and close off respective 3l84354 5/1965 Stwthe'r "156/73 terminal portions of the severed blood vessels while perform- 3l93'424 7/965 Scott ing surgical procedures. The tool member, of a proper con- 3'49'447 12/1968 "56/73 figuration, may alsojoin together layers of tissue, including l586'645 6/1926 17 the walls of unsevered blood vessels, and with respect to thel'sslzso 10/1932 Tomlinso; "us/303' latter is foreseen as replacing the tying off" of arterres and 2:714:890 8/1955 Vang .3................::::.....128/305 "einscummly necessary in PE AK TOOL- 20 Claims, 29 Drawing Figures VELOCITY FREQUENCY OF 2. MECHANICAL VIBRATION VIBRATION ENERGYPRESSURE ABSORPTION 3. APPLIED WITH IN TISSUE TOOL T1$5UE 4- TOOL WORKING CLOSURE SURFACE on 301mm.

5 currme EDGE FRICTIONAL Ruaamo TOOLHEAT 6TEMPERATURE 1 DEVELOPMENT INT1ssuE 7 OXYGEN FOR CLOTTlNG PATENTED JMSWZ 3.636.943

SHEET 1 OF 5 PEAK TOOL VELOCITY FREQUENCY OF MECHANICAL VIBRA 0N VIBRATION ENERGY PRESSURE ABSORPTION APPLIED WITH T'SSUE TOOL TOOL WORKING T'SSUE c osu SURFACE L RE 0R JOINING CUTTING EDGE E- .E.h

FRICTIONAL RUBBING TOOL C op T TEMPERATURE DE IN TISSUE OXYGEN FOR CLOT TING LEWIS EA LI- MIJH PATENIED JANZS I972 F/G.3 B

SHEET 3 OF 5 28a wawzsa PATENTEDJANZSEII'Z 3.636.943

saw u or 5 FIG. 6 62! 564 25 1 LEWIS BALMMT,

HY W MM ULTRASONIC CAUTERIZATION BACKGROUND AND SUMMARY OF THE INVENTION The present invention relates generally to improvements in surgical procedures whereby ultrasonic energy is utilized and more particularly to methods and apparatus for closing off the terminal portions of severed blood vessels to stop or prevent the flow of blood therefrom during the surgical procedure and the joining of layers of tissue in biological organisms such as humans.

The outstanding and unexpected results obtained by the.

practice of the method and apparatus of the present invention, are attained by a series of features, steps and elements, working together in interrelated combination, and may be applied to biological organisms in general and particularly humans, and hence will be so illustrated and described with respect to humans. 7

Applicant has already participated in earlier developments which led to US. Pat. No. 3,086,288 covering the use of an ultrasonically vibrating scalpel or knife. The aim of that invention was to increase the ease with which a surgical knife could be used to cut organic tissues.

We are concerned in the present invention with new discoveries by applicant which allow dramatic improvements in the operation of high-frequency vibrated knives, and also extend the use of the side area or working surface of a knife to perform a useful function, especially in relation to preventing or stopping bleeding.

Before proceeding to the details of the invention, let us first review briefly generally known facts of bleeding. The blood or circulatory system of the body (for warm blooded animals and humans) is comprised of two great and complex systems of arteries and veins. The arteries carry blood from the heart and these arteries divide in a complex network of smaller arteries or arterials, which in their turn connect to an extraordinarily complex network of very fine blood carrying tubes called capillaries. These capillaries are in communication with all the cells of the body and they provide the nutrients needed to feed these cells and they also supply the white blood cells needed to dispose of wastes and, in general, to police the cells and their environment in respect to unwanted substances and agents. After doing their job, the blood cells find their way back to the heart by means of a similar network of capillaries which join up to veinules or small veins, which in turn connect to veins which ultimately bring the blood back to the heart. There is also a lymph system which participates in this process, wherein again small tubes containing lymph (a kind of blood plasma with white corpuscles and waste products) convey this lymph through various strainers called lymph nodes and then, ultimately by means of the thoracic duct the purified lymph flow back into a large vein in the neck.

Now when the body is cut into at any location, in general a number of the tubes or vessels carrying blood are severed in this region. This severance will include many capillaries, some small veins and arteries and in some cases even a regular artery or a vein or both. The capillaries comprise an area which is as much as 100,000 times the area of the arteries and veins, and thus it is seen that many more capillaries are involved per incision than any other vessels. The severing of capillaries produces an ooze of blood which must be mopped up or swabbed during an operation, while the larger blood vessels involved must be clamped or tied off to prevent bleeding during the surgery. The attending of these bleeding problems takes up about 67 percent of the time of most operations. it is a major aim of this invention to reduce this lost time considerably and at the same time to reduce the total loss of blood and to promote the healing of the wounds created. This is accomplished by the design of ultrasonic instruments so as to enhance those uses of ultrasonic energy needed to accelerate the desired objective, namely to stop bleeding.

Ordinarily, bleeding stops by virtue of the interaction between small bodies in the blood stream called platelets and the oxygen in the air, whereby the platelets disintegrate and form a network of fibers called fibrin which slow up and finally stop the blood flow by the formation of suitable clots. Heat may be used to accelerate this process, and in fact both electric cautery and hot wire cautery 'are used in controlling bleeding in some procedures. But these types of cautery produce, in addition to rapid clotting, an extensive destruction to all tissue, thereby requiring a long time in the healing. By means of ultrasonic energy it is possible to promote the clotting with far less damage, as will be disclosed herein, so that bleeding may be very quickly halted and at the same time, much quicker healing will take place.

Electric and hot-wire cautery as well as cryogenic techniques are not effective for the care of bleeding from veins and arteries and it is here that special tying-off methods or he tatic clamping techniques are used. lt is a further aim of this invention to teach how tying-off and clamping techniques may be replaced by utilizing ultrasonic energy in the proper way.

In all the ways whereby ultrasonic energy is used in this invention, the tool member supplying the energy executes vibrations of high frequency and small amplitude. Since the development of the ultrasonic knife, in part by present applicant, new alloys have become generally available which permit the maximum amplitude of vibration at a given frequency to be increased substantially. For example, in regular use a scalpel could be vibrated at 20 kc./sec. with a stroke of two to at most four thousandths of an inch. A larger stroke would cause a rapid fatigue failure of the ultrasonic motor driving the scalpel. With a new alloy of titanium (titanium with 6Al-4V is one such) it is possible to go to strokes as high as 8 or l0 thousandths of an inch. This means that the rubbing action of a single stroke may be greatly enhanced, because the peak velocity achieved during the stroke is more than double the peak velocities previously attainable on a practical basis.

This improvement led applicant into the development of procedures and tools whereby such large ultrasonic motions could be put to work to stop capillary bleeding while cutting the surrounding tissue. In order to understand this, let us consider the transfer of energy which occurs during cutting. Wherever the tissue comes into contact with the cutting tool or scalpel, the tool member is moving to and fro at high frequency parallel to the surface of the tissue being severed. To the extent that there is good acoustic coupling between tissue and tool, there will be a transfer of shear waves into the tissue. But, tissue is of an acoustic nature as to be practically incapable of supporting high-frequency shear waves. Therefore, the shear waves damp out very rapidly and dissipate their energy in the superficial tissue as heat. This promotes fibrin formation and clotting at the capillaries, while the damage to underlying tissue is minimal due to lack of penetration of this clotting energy. To the extent that the tool slips past the tissue during its to and fro motion, a rubbing action is set up, due to relative motion of tool and tissue and a frictional heat is generated at the tool tissue interface, again producing a heating and clotting action on the adjacent terminal portion of the opened capillaries and other blood vessels. Thus, entirely due to the ultrasonic to and fro motion of the tool, a cooperative dual effect is engendered whereby the ooze" during an operation is efiectively stopped while cutting.

Applicant has further found that the peak rubbing speed, which equals rrfx the peak to-and-fro stroke (f= frequency of tool) is relatively constant with respect to frequency. This is because the peak strain set up in the ultrasonic motor driving the cutting tool depends directly on the peak speed of the cutting tool and not on the peak frequency. Of course, this merely means that if one wishes to operate at a higher frequency, then one has to be content with a proportionately I used to actually sever the tissue itself. This latter component of energy is only a small fraction of the tool energy used.

In actual practice, applicant has discovered that, by texturing or roughening the sidewalls of the cutting tool, the transfer of superficial cauterizing energy is increased so as such for certain surgical procedures it is preferable to use scalpels whose working surfaces or side faces are roughened rather than very smooth. The same principle applies to spatulate tools wherein no cutting is contemplated, but the tool is designed primarily to cauterize an already opened bed of blood vessels such as capillaries in a wound. In the case of the spatulate tool the amount of energy transfer may be increased by pressing the spatula tool working surface, while vibrating, with increased pressure against the wound to apply a compressive force for the transmission of the shear waves or increasing the frictional rubbing. Applicant has also discovered, that although it is not essential, it is nevertheless desirable to supply the cutting edge of a knife or scalpel with a set of small serrations. This further aids in clotting, and permits faster artery by clamping it in a specially designed ultrasonic instrument, so that the walls of said blood vessel are briefly clamped while vibrating one or both of the tool jaws. Since this same principle applies to other soft body tissue such as the skin, this same type of tool may be used in place of the conventional suturing which is used in closing incisions in surgical procedures.

Thus, it may be seen that we are dealing with a highly complicated set of phenomena in practicing applicants method of bloodless surgery. At this time, it is not known quantitatively just how large a role is played by each factor, such as shear wave absorption, frictional heat production and tissue sealing. The point is that by employing ultrasonic motors capable of producing generally higher strokes than previously available, the combination of effects permits for the first time, true bloodless surgical procedure by ultrasonic means. Where extremely fast procedures are essential, one may also resort to auxiliary heating of the vibrating tool member, but only to subcautery temperatures. This temperature is preferably above room temperature but below a temperature that would normally burn the tissue. This may be accomplished conventionally, or in accordance with the method disclosed in U.S. Pat. No. 3,321,558 in which applicant is a coinventor.

OBJECTIVES OF THE INVENTION An object of the present invention is to provide an improved method and apparatus for forming surgical procedures with ultrasonic energy.

Another object of the present invention is to provide an improved method and apparatus for securing together layers of tissue in biological organisms, such as humans.

Yet another object of the present invention is to provide an improved method and apparatus for forming closures at the severed terminal portions of blood vessels in vivo, which blood vessels are in the general neighborhood of what are called capillaries, so as to prevent "ooze, which requires contact mopping or cleansing during surgical operations.

A further object of the present invention is to provide improved method and apparatus for permanently or temporarily closing off blood vessels so as to replace the tying off" of arteries and veins currently necessary in surgery.

Still another object of the present invention is to provide a method and apparatus of bloodless surgery which combines the surgical cutting of tissue and a closing off of the severed blood vessels to prevent the "ooze" normally associated with operations.

Yet still another object of the present invention is to provide a method and apparatus for simultaneously joining and trimming, as by cutting, a large blood vessel.

Yet still a further object of the present invention is to provide an improved method and apparatus for ultrasonically joining together layers of tissue.

Still a further object of the present invention is to provide an improved method and apparatus for increasing the flow of oxygen to the terminal portion of the severed blood vessel to expedite the clotting of the blood thereat.

Still yet a further object of the present invention is to provide an improved sealing apparatus for joining together layers of human tissue.

Still yet a further object of the present invention is to provide specially designed tools adapted to be ultrasonically vibrated and employed in surgical procedures.

Other objects and advantages of this invention will become apparent as the disclosure proceeds.

BRIEF DESCRIPTION OF THE DRAWINGS Although the characteristic features of this invention will be particularly pointed out in the claims, the invention itself, and the manner in which it may be made and used, may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part hereof, wherein like reference numerals refer to like parts throughout the several views and in which:

FIG. 1 is a chart indicating the relationship of the principal factors affecting the practicing of the present invention for surgical procedures;

FIG. 2 is an assembled somewhat schematic view of an ultrasonic motor generator system of the type in which the motor is capable of being hand held and manipulated, for driving a tool member adapted to engage the biological organism for performing a surgical procedure, and which in the present instance the tool member is illustrated as a knife for severing blood vessels, the latter shown on a greatly enlarged scale for discussion purposes;

FIG. 3 is a side view of an ultrasonic tool member having a textured working surface in accordance with the present invention;

FIGS. 3A and 3B are end views of the tool member in FIG. 3 and illustrates two preferred ways of obtaining the textured working surface;

FIG. 4 is a greatly enlarged schematic representation of a portion of a tool member with its working surface in engagement with the terminal portion of a blood vessel for forming a closure thereat to prevent the flow of blood from said terminal portion;

FIG. 4A is an enlarged section view taken alongline 4A 4A of FIG. 4 to illustrate the interfacial contact between the tool working surface and blood vessel for the transmission of frictional energy and shear waves for localized heating of the terminal portion;

FIG. 4B is a greatly enlarged schematic representation illustrating an ultrasonically vibrating tool member engaging a severed portion of tissue for simultaneously forming a plurality of closures at the terminal portions thereof;

FIG. 4C is a greatly enlarged schematic representation illustrating the angular relationship between the tool member and blood vessel which defines a terminal plane that may define an extreme angle with the axis of the blood vessel and still obtain the desired results of the present invention;

FIG. 4D is an end view of the tool member and blood vessel of FIG. 4C;

FIGS. 5, 5A, 5B and SC are enlarged schematic representations in cross section of the method of forming a closure at the terminal portion of a blood vessel in which the sidewalls thereof are joined together;

FIG. 5D is an extremely enlarged view of a blood specimen to illustrate some of the important components thereof;

FIGS. 6 and 6A are enlarged schematic representations in cross section of the method of forming a closure at the terminal portion of a blood vessel in which the closure is formed by partially converging the sidewalls thereof and forming a blood clot in the reduced opening;

FIGS. 7 and 7A are enlarged schematic representations in cross section of the method of forming a closure at the terminal portion of a blood vessel in which the closure is formed by primarily forming a blood clot at the terminal portion thereof;

FIGS. 8 and 8A are side and end elevational views respectively, of a spatula tool member having a textured working surface for ultrasonic cautery;

FIG. 9 is an enlarged sectional view illustrating the forming of a plurality of closures on respective terminal portions in an open wound by the use of a spatula-shaped tool;

FlG. 10 is a top longitudinal view, of one preferred form of ultrasonic system, of the type capable of being hand held and manipulated, for joining together layers of tissue, such as in humans;

FlG. 11 is a side longitudinal view, partly in cross section, of the ultrasonic system of FlG. l0;

FIG. 12 is an enlarged schematic view, in cross section, illustrating the application of the ultrasonic instrument illustrated in FIGS; 10 and 11 for securing together the walls of a,

DETAILED DISCUSSION OF THE DRAWINGS The high-frequency transducer means may be either in the sonic or ultrasonic frequency range but for purposes of the present invention the word "ultrasonic will be used to denote vibrations in the range of approximately 5,000 to 1 million cycles per second. ln addition the term blood vessel" as used herein is intended to include any tubular member of the human body, but particularly ca ilarles, a s, ve' ules, arteries and veins.

ln performing the surgical procedures of the present invention there are several factors that have to be taken into consideration and analyzed in terms of a total or effective value to obtain the desired end results. The term total value may be defined as the proper combination of these factors to obtain the desired end result.

Referring now to the drawings, FIG. 1 is a chart illustrating the relationship of the seven principal factors which are involved in whole or in part for determining the total value associated with fon'ning closures at the terminal portions of severed blood vessels, or joining together overlapping segments of layers of human tissue. The related factors are-peak tool velocity, frequency of vibration, pressure applied with tool, tool working surface, cutting edge, tool temperature and oxygen for clotting. These factors vary with respect to the procedure being performed.

In the embodiments of the invention discussed below the working surface of the tool member is placed in engagement with at least one of the layers of tissue at a surface thereof such that a small compressive force is applied in a plane substantially normal to the engaged surface. While this compres: sive force is maintained the working surface of the tool member is vibrated at an ultrasonic rate to apply an additional energy producing force at the engaged surface. The compressive and energy producing forces are continued until the layers of tissue are secured together by the combined action of these forces.

When these layers of tissue form the walls of blood vessel the forces are applied to the terminal surface thereof for producing localized heating in forming a closure to prevent the blood from escaping therefrom. The energy producing force may be divided into-mechanical vibration energy absorption in tissue-- and-frictional rubbing heat development in tissue-both of which result in a localized heating of the walls of the blood vessel to obtain the-tissue closure. The performing of surgical procedures as related to this aspect of the invention is discussed with reference to FIGS. 2 through 9, inclusive.

In contrast to this we have the joining of layers of tissue in overlapping relation to each other and in which case the compressive and vibrational forces are applied to one of the overlapped surfaces in a planesubstantially normal thereto and in which case we primarily rely on-mechanical vibration energy absorption in tissue-to obtain the tissue joining. The performing of surgical procedures as related to this aspect of the invention is discussed with reference to FIGS. 10 through 12D, inclusive.

Referring again to the drawings, and with respect to FIG. 2, it will be seen that anapparatus 10 for ultrasonically performing surgical procedures on a biological organism, such as a human, may include an ultrasonic transducer or motor 11 for effecting the necessary high-frequency vibrations of thetool member 13, such as a knife, having a sharp output edge orsurface 15 with a workingsurface 16. The ultrasonic motor 11, as illustrated may be in the form of a driving member adapted for being hand held as by an operator l2, and generally comprising a tubular housing or casing 14 into which aninsert unit 17 supporting thetool member 13 may be partially telescoped. The ultrasonic motor 11 is energized by anoscillation generator 18, with apower cable 19, connecting the two together. The generator is an oscillator adapted to produce electrical energy having an ultrasonic frequency.

The ultrasonic motor 11 may be one of a variety of electromechanical types, such as electrodynamic, piesoelectric and magnetostrictive. The ultrasonic motor for effecting surgical procedures through hand directed tools of suitable configuration, which are readily replaceable or interchangeable with other work performing tools in acoustically vibrated material treating devices, may be of the type disclosed in U.S. Pat. No. Re. 25,033, 3,075,288, 3,076,904 and 3,213,537, and wherein each work tool member is rigidly joined, in endto-end relationship to a connecting body or acoustic impedance transformer and to a transducer which may form an insert unit or assembly which is removably supported in a housing containing a coil in surrounding relationship to the transducer and receiving alternating current for producing an alternating electromagnetic field.

The transducer in the ultrasonic motor ll is longitudinally dimensioned so as to have lengths which are whole multiples of half-wavelengths of the compressional waves established therein at the frequency of the biassed alternating current supplied so that longitudinal loops of motion as indicated byarrow 23, occur both at the end of theinsert unit 17 to which thetool member 13 is rigidly connected and the knife edge. Thus, the optimum amplitude of longitudinal vibration and hyperaccelerations oftool member 13 is achieved, and such amplitude is determined by the relationship of the masses of thetool member 13 andinsert unit 17 which may be made effective to either magnify or reduce the amplitude of the vibrations received from the transducer.

Thetool member 13 may be in the form of relatively flat metal spatula member, as shown in FIGS. 8 and 8A,.

end ofinsert unit 17, for example, by brazing, solder or the like, or the tool may be provided with a tW adapted to be screwed into a tapped hole in the end ofinsert unit 17 for effecting the rigid connection of the tool to the stem. A base portion 2] is provided from which thestud 20 extends, from one end thereof, and from the other end a body 28 which is firmly secured thereto for the transmission of the ultrasonic vibrations. The body 28 may be brazed or welded to thebase 21 of thetool member 13. A tapered surface 22 may be provided which connects the cutting edge with the working surface I6.

As seen somewhat schematically in FIG. 2 thebiological organism 25, such as a human, contains a layer of outer tissue or skin 26, an internal cellular structure 27 with a plurality ofblood vessels 30 extending therethrough shown in an enlarged scale, as well as in the skin (not shown).

FIGS. 3, 3A and 3B illustrate various types of replaceable surgical implements, such as knives, that may be employed in accordance with the present invention. The knife 13a of FIG. 3 is similar to that illustrated in FIG. 2 and includes abase portion 21a, capable of supporting ultrasonic vibrations and adapted to be set into vibration in a given direction by the driving member. A threaded stud 200 extends from one end of thebase 21a for engagement with the insert unit. The body portion 280, in the form of a cutting blade, extends from the opposite end of thebase 21a and includes a textured workingsurface 16a for enhancing the coupling action between the tool member [3a and the terminal portion of the severed blood vessels to be engaged. The cutting edge 150 may be serrated and have an outwardly tapered portion 22a between thecutting edge 15a and the substantially flat workingsurface 16a. Thetextured surface 16a may begin in close proximity to or start at the workingedge 15a so that when cutting and sealing small capillaries the rubbing action and transmission of shear waves begins immediately. The textured surface finish of 16a may vary from a micro finish in the range of IO microinch to I0,000 microinch, but preferably in the range of 40 microinch to 200 microinch.

As illustrated in FIG. 3A the tool member 130 includes a body portion 280 having a coated textured layer offriction inducing material 29a which forms the workingsurface 16a and which may be of diamond or steel powder particles bonded to the body portion in any conventional manner well known in the art, to obtain the desired micro finish. The layer of coated material may be applied to both surfaces of the tool member and each surface may be of the same or different microfinish to obtain a debriding and superficial cauterizing. The advantages are quicker healing as well as less damage to the tissue being treated.

FIG. 38 illustrates the obtainment of the workingsurface 16a by finishing the metallic body 280 in any conventional manner to obtain the desired surface roughness. By providing the textured surface it is possible to control the rate of frictional heating of the blood vessels. The surface roughness is generally selected in accordance with the ultrasonic rate of vibration and the compressive force to be applied. This will in many instances relate to the particular surgeon performing the operation.

THEORY OF PRESENT INVENTION Whereas a scientific explanation of the theory based on the phenomena involved is disclosed below, it is to be clearly understood that the invention is by no means limited by any such scientific explanation.

Applicant has now discovered thatmechanical vibrations properly applied may produce closures at the terminal ends of blood vessels to prevent the fiow of blood therefrom and also join together layers of human tissue. With respect to forming the terminal closure it is possible to simultaneously cut through layers of tissue and seal off the terminal ends.

For purposes of illustration, we have in FIGS. 4 and 4A asingle blood vessel 30b having awall 31b with aterminal portion 33b terminating in an end surface 3217, the latter in engagement with the workingsurface 16b of thetool member 13b which is being ultrasonically vibrated in thedirection 23b.

At the interface of the workingsurface 16b andterminal surface 32b we have a transmission of both rubbing forces and mechanical vibrational energy to theblood vessel 30b which results in a localized heating of theterminal portion 33b. FIG.

4A illustrates the contour of the surfaces in engagement with each other and the transmission of the shear waves over the distance D. The pressure applied with the tool member, partially determines the degree of shear waves and rubbing vibrations transmitted 'to theterminal portion 33b of the blood vessel for a given textured tool. At point P, shear vibration is developed in the tissue 310, then at P, the shear vibration has dropped almost to zero whereby the shear vibration energy is converted into heat in the tissue of the blood vessel. The smallness or minimal depth of penetration of P,, P, is what makes for quick healing and cauterizing action of the tool member.

Theshear wave pattern 35b extends the distance D, which is the distance from P to P along theblood vessel 30b to obtain the localized heating of the terminal portion. The coupling action at the workingsurface 16b andblood vessel 30b is enhanced by the application of the small compressive force. as indicated byarrow 36b, in a plane substantially normal to the plane defined by said tenninal end surface 321). At P in addition, to the extent that shear vibration is not induced in the tissue, there will be a slippage and a frictional rubbing action which will also produce heat practically instantaneously at P,. It is a combination of these effects which create the closure at the terminal portion of the blood vessel.

It will be appreciated that the relative amounts of shear vibration and frictional rubbing action will be determined or selected by the magnitude of the tool vibration and the tool surface in relation to the tissue surface. Many combinations are possible whereby either the frictional or the shear components may be emphasized.

The extent that the rise in temperature occurs at theterminal portion 33b of theblood vessel 30b is related to the rubbing vibrations applied and this is related to the peak speed which is:

V peak 2-rrf A A peak amplitude f frequency V= peak velocity So that if f is raised, A is lowered and we can retain the same peak speed at all frequencies. This is why the more rubs per second the higher the frequency for the same output peak speed. Accordingly the workingsurface 16b of thetool member 13b may be surface finished for sufficient roughness to allow increased friction against the tissue. This is quite different from a standard knife or scalpel which has polished sides.

The thickness of the tool member should also be held to a minimum so as to permit a more rapid local temperature rise which is attributable to the shear production and absorption in the adjacent tissue and the temperature rise due to rubbing of tissue surface, which involves slippage between tool member and tissue surfaces. We can say that during the to and fro motion, neglecting the energy of cutting itself, when a knife is used we have:

Ultrasonic energy per stroke Ultrasonic shear energy produced per stroke Frictional rubbing energy per stroke.

Since, in both cases the energy absorbed goes into superficial heating of tissue and cutting tool, we can estimate the effects by considering all the energy to be frictional for ease of making approximate calculations.

Assuming an average force of friction, F, we have the power dissipated superficially at a tool tissue interface equal to:

S stroke F average friction force P= power Now V max. for a frequency of 20 kc./s. and a stroke of 0.010 inch is approximately 50 fps. Therefore P is approximately 15 watts, when F is between one-half and l pound. Since this power is dissipated in superficial supreficial region of the cutting, the heat capacity of the tissue and the tool are quite small. For example for a steel tool of dimension lX0.l25x

dredths of a gram. In such a case it is possible to obtain local temperature rises of the order of hundreds of degrees centigrade centrigrade under the condition outlined above. This is -ample to stop ooze."

Accordingly the frequency and amplitude of vibration of said tool member is selected at a level wherein the transmitted shear waves are substantially maintained at theterminal portion 33b with only superficial penetration and heating of the remainder of theblood vessel 30b.

Accordingly, the frequency and amplitude of vibration is preferably selected at a level to provide a peak velocity of at least feet per second along the workingsurface 16b of thetool member 13b and more generally the general range of approximately 40 feet per second to 100 feet per second.

FIG. 4B shows a portion of thebiological organism 25b with an outer layer of skin 26b and a plurality ofblood vessels 30b extending through the cellular structure 27b and terminating against the workingsurface 16b of thetool member 13b. The tool member l3b is being vibrated at an ultrasonic rate in the direction ofarrow 23b, which is in a plane substantially parallel to the plane defined by theterminal end portions 33b, to induceshear waves 35b, which penetrate theblood vessels 30b and surrounding tissue structure 27b. The high-frequency vibration and amplitude of the tool member is selected to obtain only a superficial penetration and resulting heating of theterminal portions 33b so that there is a minimum of damage to the underlying tissue area 3112 and all of the blood vessels are simultaneously closed off.

As illustrated in FIGS. 4C and 4D theterminal portion 33b has anend surface 32b that defines aplane 37b that may vary in angular relationship to the axis of theblood vessel 30b. In practice the angular engagement between the working surface 161: of the tool member [3b and theend surface 32b may not always be controlled during a surgical procedure since the blood vessels such as capillaries, veinules, veins, arterials and arteries extend in various directions throughout the body. The important consideration is that the ultrasonic longitudinal mechanical vibrations, as indicated byarrow 23b, are applied having a major component of vibration parallel to theterminal plane 37b and a component of compressive force, as indicated byarrow 36b, in a plane substantially perpendicular to theterminal plane 37b.

FIGS. 5, 5A, 5B, 5C, 6, 6A, 7 an 7A illustrate the actual surgical procedure in vivo of obtaining a closure at the terminal portion of a blood vessel using the ultrasonic instrument illustrated in FIG. 2, or a tool member illustrated in FIGS. 4, 4A and 4B. As explained with respect to the theory of the present invention in FIGS. 3, 3A, 3B, 3C and 3D the degree of shear waves and frictional rubbing may be controlled so that a predominant reliance on one or the other is produced.

In FIGS. 5, 5A, 5B and 5C theterminal closure 40c is formed primarily by producing a plastic flow of the wall of the blood vessel and containing the flow for a period of time sufficient to obtain ajoining of the severed ends together. Initially the cutting edge c of the tool member 130 is placed in engagement with theskin 26c of the body 250 and the tool member [3c is ultrasonically vibrated and a small compressive force in the direction ofarrow 360 is applied to obtain a cutting of theskin 26c and progressively sever the tissue by a continued movement of the cutting edge 150 through the cellular material 270 until the wall 310 of theblood vessel 30c is engaged. The wall 310 for purposes of discussion is considered as layers oftissue 42c and 43c, respectively.

As seen in FIG. 5A after thecutting edge 15c severs the tissue layer 420 a certain amount ofblood 44c flows from within theblood vessel 30c into theopening 450 that has been formed. As the movement of the ultrasonic instrument is continued downwardly we have the engagement of the workingsurface 16c with theterminal end portion 336 of the blood vessel to apply a compressive force to the end surface to obtain a localized heating of the terminal portion by the application of the ultrasonic mechanical vibration. The relative movement is continued so that the application of the mechanical vibrations are transmitted for a period of time sufficient for the localized heating to form theclosure 40c at theterminal portion 33c. In this manner the terminal portion 330 is closed off by the formation of the closure 45c and the blood contained therein is prevented from escaping through the closure. The closure 45c is produced at least in part by the production of said shear waves and their conversion into heat coupled with the localized heating obtained by inducing frictional rubbing at the terminal portion 330. The extent of each factor will vary with the texture of the working surface I6c and the degree of the compressive force applied by the working surface against the terminal portion.

FIG. 50 is an enlarged microscopic examination of theblood 44c and as illustrated the blood containsred corpuscles 46c,white corpuscles 47c and platelets 48c, the latter play an important role in the natural clotting of blood by producing fibrin when exposed to air. This natural clotting ability of blood is relied upon at least in part with respect to the formation of the closures illustrated in FIGS. 6, 6A, 7 and 7A.

FIGS. 6 and 6A illustrate the formation of the closure which is substantially formed by clotting of the blood at the terminal position. The workingsurface 16d is placed in engagement with the layers ofwall 42d and 43d of theblood vessel 30d, which is of a size in the capillary range, with theblood 44d contained therein. The tool member 13d preferably has a textured surface to permit air and most importantly oxygen to be delivered past the layer of skin 26d to theterminal portion 33d of the blood vessel to obtain a clotting action. Thetool member 16d acts as an ultrasonic pump and stimulates the flow of air to worksite. As the air reaches the worksite we have the additional action of the conversion of the ultrasonic mechanical vibrations to obtain a localized heating by the conversion of the frictional motion into heat and the localized heating expediates the formation of theblood clot 50d which forms the closure 40d. Since the blood vessel is relatively small in diameter we have the formation of the closure 40d that is substantially formed by a clotting of theblood 44d therein. As seen in FIG. 6A the tool member is then removed leaving the opening ofwound 45d and closures 40d fonned on each respective end of the severed blood vessels.

FIGS. 7 and 7A illustrate the fonnation of aclosure 40c by cross-sectional closing thelayers 42c and 43e of thewall 3!: of theblood vessel 30c at theterminal portions 33c by the localized heating and the remainder by forming a blood clot 50s of theblood 44c contained in the reduced area of the blood vessel. The ultrasonic tool member I3e transmits the mechanical vibration which produces a plastic flow of the wall 31a of said blood vessel which flow is continued for a period of time to obtain a reduced cross-sectional area and during which same period of time the localized heating assists in the formation of the blood clot 502 which together with the reduced area forms theclosure 40c to prevent the blood from escaping therefrom. The tool member is then removed past the skin 26 leaving the opening 45c.

It is appreciated that the process although illustrated for a single blood vessel can be occurring simultaneously on a plurality of blood vessels. To increase the rate at which the closure is formed and reduce healing time the working surface of the tool member may be heated to a temperature level which is above room temperature, but below a temperature that would normally sear the terminal portion of the blood vessel. The temperature of the tool may be heated in any conventional manner, as for example, in accordance with US. Pat. No. 3,321,558.

There are instances in surgical procedures where it is desirable to be able to stop bleeding independently of having previously cut the tissue of the body. As for example, in gunshot wounds and other accidents it is often desirable to stop bleeding and accordingly spatulalike tools in accordance with the present invention may be utilized.

FIGS. 8 and 8A illustrate one form of readily replaceable implement, in the form of a spatulalike tool member l3f, having a body portion 28] with substantially flat parallel working surfaces 16f that have been textured to a preselected micro finish to provide means for coupling the ultrasonic vibrations to the terminal portions of the blood vessels. The surface finish is selected for the transmission of rubbing vibrations and shear waves to obtain the localized heating. One end of thespatula body portion 28f is fixedly secured to thebase portion 21f, and the latter has a threadedstud 20f for securement to the ultrasonic driving member. Thebase portion 21f is preferably of a metallic material capable of supporting ultrasonic vibrations and adapted to be set into vibration in a given direction at ultrasonic frequencies. Thebody portion 28f may be in the order of 0.010 to 0.160 inches thick and be concave in configuration for strength reasons. It may also be designed to vibrate elliptically to permit intermittent separation of the tool member and terminal portions to promote the flow of air to the terminal portions for clotting. The obtainment of elliptical vibration for vibratory elements is well known in the art, for example, as illustrated in US. Pat. No. 2,990,916 in which applicant is a coinventor thereof.

As illustrated in FIG. 9 the spatulalike tool member is illustrated for surgical procedures in which it is desired to form closures at terminal ends ofblood vessels 30g separately from when the actual cutting is performed. Accordingly thespatulalike tool 13g is inserted within theopening 45g of the body g such that the working surface 163 of thetool member 13g applies a compressive force against theterminal portions 33g of the severed blood vessels. The compressive force is applied in the direction of arrow 36g. Thetool 13g is simultaneously vibrated, in a direction as indicated by arrow 23g, and at an ultrasonic rate to transmit mechanical vibrations to theterminal portion 33g of the blood vessels to obtain a localized heating of at least some of the tenninal portion. The application of said compressive force and mechanical vibrations are continued until a closure at the terminal portion is formed and the blood contained therein is prevented from escaping through the formed closure. The thickness of thespatula tool member 13g may be narrower, as illustrated in FIG. 9, than the opening 453 in the body, such that only one surface 163 engages the severed blood vessels. If desired the width of the spatula body 28 may be substantially equal to thatofthe body opening 45g so that both terminal ends 33g of a respective blood vessel g is closed during one insertion of the tool member within the wound.

The localized heating to obtain the closures may be induced by frictional rubbing at the terminal portion 333 of theblood vessel 30g so that the closure is produced at least in part by frictional heating. By providing a textured surface to thetool member 13g the rate of frictional heating may be controlled when combined with the other factors to produce the terminal closure. Depending upon the thickness of the spatula tool member either pure longitudinal vibration will be obtained or a flexural component of motion, as indicated by thearrow 51g, so as to obtain elliptical vibrational motion along the working surface 16g. This permits intermittent disengagement between the wall surface or terminal end of theblood vessel 33g and the working surface 16g so that air and in turn oxygen may be continuously supplied to the work site to assist in the clotting of the blood.

FIGS. 10 and 11 illustrate one form 10h of the ultrasonic system for joining together in vivo, overlapping layers of organic tissue. The system includes a hand held instrument including an ultrasonic motor llh, which may be the type as discussed with reference to FIG. 2, and include atool member 13h having anenlarged portion 53h terminating in a workingsurface 16h that extends in a plane substantially normal to the direction of mechanical vibrations illustrated by thearrow 23h. The base 2111 of thetool member 13h is secured to theinsert portion 17h. Support means 55h is provided to act as an anvil or clamp so that the overlapped layers oftissue 42h and 43h of thewall 31h of theblood vessel 30h may be compressed between the vibratory working surface and a support surface.

The support means 55h includes a pair oflegs 56!: and 5711 respectively, secured together at their lower end bybands 58h and provided with gripping means in the form ofindividual lugs 59h that extend outwardly from the upper end of the legs for engagement by the fingers of the surgeon oroperator 12h in a manner hereinafter described. Theleg 57h has alower ex tension 60h that terminates in asupport arm 61h at substantially right angle to theextension 60h, and is provided with asupport surface 62h in spaced relation to the workingsurface 16h ofthetool member 13h.

Thelegs 56h and 57h are in spaced relation to each other and may be contoured to conform to the cylindrical configuration of theultrasonic transducer housing 14h. The generator l8h is connected to the transducer llh by means ofcable 19/: in a conventional manner. As seen in FIG. 10 thecable 1% may enter the ultrasonic motor llh from the side so as to leave therear end 63h free for engagement by the thumb or any other finger of the surgeon to permit manual control of the relative displacement between the overlapping working and support surfaces.

The support means 55h is mounted for relative movement, with respect to the ultrasonic motor llb by providing a pair ofslots 65h on each of thelegs 56h and 57h, and which slots accept headedfasteners 66h which extend from thecasing 14h through theslots 65h to permit free relative movement between the ultrasonic motor llh and support means 55h. The lower end of thecasing 14h is provided with anannular shoulder 67h which is adapted to receive spring means in the from of aspring 68h which is contained within theshoulder 67h at one end thereof and in engagement with thebands 58h at the opposite end thereof. Thespring 68h applies a force in the direction ofarrow 68h, so that the working surfaces of the support means and ultrasonic motor means are biassed away from each other whereby the force applied by the surgeon is required to bring the overlapping working and support surfaces together. lf desired the spring may be coupled to the support and ultrasonic motor means so as to force them together with a predetermined static force which might be varied in a conventional manner not shown. in this manner once the static force is determined for the particular thickness of tissue the resultant permanent or temporary seal may be obtained. Accordingly the spring means may yieldably urge the support means 55h and transducer means llh relative to each other to a position wherein the working and support surfaces l6h and 62h, respectively, are normally in engagement with each other under a predetermined static force, so that the support and transducer means are first separated for the placement of the layers oftissue 42h and 43h therebetween. In contrast to this the spring means may be adjusted such that the working and support surfaces are normally maintained in spacially fixed relation to each other, so that the layers 42): and 43h are positioned between the surfaces which are brought together by the operation of the hand held instrument.

As previously explained during surgical procedures it becomes necessary to tie-off veins and arteries so as to prevent the flow of blood therethrough. In accordance with the invention thejoining of the walls may be ofa permanent or semipermanent nature, and this is accomplished by properly selecting the frequency and amplitude of ultrasonic mechanical vibrations to produce an optimum flow of the collagenous elements contained in the overlapping portions of tissue. This collagenous material is similar to that non'nally found in the formation of scar tissue. In practice the ultrasonic instrument 10h may be employed tojoin together, at a select area the wall of a blood vessel and as seen in FIG. 10 thewall 31h may be considered to include the overlapping layers oftissue 42h and 43h.

As seen in FIGS. l2, 12A and 128 we have theblood vessel 30h exposed within anopening 45h within theorganic body 25h. To produce ajoining of the overlapping layers ofwall tissue 42h and 43h respectively, thearm 61h of the support means 55h is placed beneath theblood vessel 30h and the workingsurface 16h of thetool member 13h is brought into contact with the layer of tissue 42):. The working andsupport surfaces 16h and 62h are moved relative toward each other until theblood vessel 30h has the overlapping layers of tissue 42!: and 43!: in contact with each other as seen in FIG. 12A. Simultaneously therewith a small compressive force, in the direction ofarrow 36h, is applied to the layers of tissue traversing the area of overlap.

The working surface of thetool member 13!: is vibrated at an ultrasonic rate, as for example, in the frequency range of from l kc./s. to l00 kc./s. and preferably in the range of kc./s. to 40 kc./s., so as to apply an additional recurring force to the overlapped layers of tissue, and produce a superficial heating at the interface of the overlapped layers. The vibrational force has a substantial component of vibration normal to the overlapped surfaces, as indicated by thearrow 23h. The frequency of the ultrasonic rate of vibration is selected in the above frequency range so as to preferably also produce an optimum flow of the collagenous elements in the overlapped layers of tissue. The energy is then continually applied until a closure orbond 40h is formed between the collagenous elements in the overlapping layers of tissue, as seen in FIG. 12B, and the blood is prevented from flowing past the closure. The closure 40!! may be of a temporary nature or permanent one depending upon the proper control of the vibratory energy and static force to fuse together the superficially heated interface.

For certain applications it is desirable to join together the overlapping layers of tissue and at the same time cut off the excess material. As illustrated in FIG. 12C the support arm 61] is provided with acutting edge 70j and as the overlapped layers of tissue 42] and 43] are compressed between the working surface l6j and support surface l6j and joined together by the energy transmitted through the tool member l3j and the excess tissue layers 7lj and 72j are cut off. If desired the cutting edge may be placed on the working surface l6j of the tool member 13].

For those applications in which it is desired to intermittently join together overlapping layers of tissue we have the apparatus illustrated in FIG. l2D..The overlapping layers oftissue 42k and 43k are first clamped together by clampingmeans 75k which includes clampingmembers 76k and 77k which may form part of the ultrasonic instrument or may be the forward portion of a pair specially designed clamping instrument. The clamping means 75k is applied in close proximity to the area of overlap of the layers oftissue 42k and 43k to be joined together. Theultrasonic instrument 10k includes the support means 55k for engaging one side of the overlapped layers of tissue and which opposite side is engaged by thetool member 13k which as illustrated is provided with a circular working surface. By intermittently moving the ultrasonic instrument along the area of overlap a number of closures or bonds 30k, such as stitches may be formed.

While the invention has been described in connection with particular ultrasonic motor and tool member constructions, various other devices and methods of practicing the invention will occur to those skilled in the art. Therefore, it is not desired that the invention be limited to the specific details illustrated and described and it is intended by the appended claims to cover all modifications which fall within the spirit and scope of the invention.

lclaim:

l. A method of superfically cauterizing a wound at the terminal portion of severed blood vessels in vivo, with a noncutting spatulalike tool member having a working surface, comprising the steps of A. applying the working surface of said tool member in engagement with the terminal portion of said blood vessels, said tool member being at substantially room temperature,

B. retaining said tool member in a position relative to said severed blood vessel,

C. maintaining a compressive force against said terminal portion in a plane substantially normal to said engaged surface with said noncutting spatula like tool member,

D. vibrating the working surface of said tool member at a peak velocity of at least l0 feet per second and simultaneously with the maintaining of said compressive force to apply ultrasonic mechanical rubbing vibrations substantially parallel to the terminal portion of said blood vessels in a direction so as to apply an additional energy produc: ing force to obtain a localized heating of the terminal portion, the direction of said mechanical vibrations being applied to produce shear waves at the terminal portion of said blood vessels, and said blood vessels, and said localized heating of the blood vessels is obtained by the conversion of said shear waves to heat, whereby said superfical cauterization is produced at least in part by the production of said shear waves, and

continuing the retaining of said tool member in a position relative to said severed blood vessels and the application of said mechanical rubbing vibrations for a period of time sufficient for said localized heating to form a superfical cauterization at the terminal portion. whereby the terminal portion is closed oh and the blood contained therein is prevented from escaping.

2. A method as claimed inclaim 1 wherein said localized heating is also obtained by simultaneously inducing frictional rubbing at said terminal portion of said blood vessel by the application of said mechanical vibrations, whereby said cauterization is produced at least in part by said frictional heating.

3. A method as claimed inclaim 1, wherein said blood vessel is relatively small in diameter and said cauterization is substantially formed by clotting of the blood at said terminal portion thereof.

4. A method as claimed inclaim 1, wherein said cauterization is at least in part formed by a blood clot, and said localized heating expedites the formation of said blood clot.

5. A method as claimed inclaim 1, wherein said cauterization is formed by partially closing the blood vessel by said localized heating and the remainder by clotting the blood contained in said reduced area of the blood vessel.

6. A method as claimed in claim I, wherein said mechanical vibration produces a plastic flow of the wall of said blood vessel and said flow is continued for a period of time sufficient to obtain a joining of the wall of said blood vessel to from said closure.

7. A method as claimed in claim I, wherein said blood vessel is a capillary.

8. A method as claimed in claim I, wherein said blood vessel is an arterial.

9. A method as claimed in claim I, wherein said blood vessel is a veinule.

10. A method as claimed inclaim 1, wherein said blood vessel is an artery.

ll. A method as claimed inclaim 1, wherein said blood vessel is a vein.

12. A method as claimed inclaim 1, wherein said ultrasonic mechanical vibrations are applied over and area to. simultaneously close off a plurality of blood vessels.

13. A method of superfically cauterizing severed blood vessels of a wound in vivo, with the aid of a noncutting spatula like tool member having a working surface, comprising the steps of A. applying the working surface of said tool member against the terminal portion of said blood vessels, said tool member being at substantially room temperature,

B. retaining said tool member in a position relative to said severed blood vessels,

C. maintaining a compressive force applied along a line substantially perpendicular to the plane defined by the terminal portion of said blood vessels with said noncutting spatula like tool member,

D. simultaneously vibrating the working surface of said tool member, at a peak velocity of at least 10 feet per second and, while maintaining said compressive force, in a direction and at an ultrasonic rate to transmit mechanical vibrations to the terminal portion, said localized heating is obtained by inducing friction rubbing at the terminal portion of said blood vessels by the application of said mechanical vibrations, and

E. continuing the retaining of said tool member in a position relative to said severed blood vessels and the application of said compressive force and mechanical vibrations until a superfical cauterization at said terminal portion is formed, whereby the blood contained therein is prevented from escaping.

14. A method as claimed inclaim 12, further including the step of controlling the rate of frictional heating of the terminal portion of said blood vessel.

15. A method as claimed inclaim 14, wherein said rate of frictional heating is controlled by texturing said toolworking surface to a surface roughness selected in accordance with the ultrasonic rate of vibration and compressive force to be applied.

16. A method as claimed inclaim 13, wherein the application of said mechanical vibrations also simultaneously produce at least in part shear waves at said terminal portion, and the frequency and amplitude of vibration of said tool member is selected at a level wherein said transmitted shear waves are substantially maintained at the terminal portion with only superficial penetration and heating of the remainder of said blood vessel.

17. A method as claimed inclaim 13, wherein said peak velocity is in the range of approximately 40 feet per second to i [00 feet per second.

Claims (20)

1. A method of superfically cauterizing a wound at the terminal portion of severed blood vessels in vivo, with a noncutting spatulalike tool member having a working surface, comprising the steps of A. applying the working surface of said tool member in engagement with the terminal portion of said blood vessels, said tool member being at substantially room temperature, B. retaining said tool member in a position relative to said severed blood vessel, C. maintaining a compressive force against said terminal portion in a plane substantially normal to said engaged surface with said noncutting spatula like tool member, D. vibrating the working surface of said tool member at a peak velocity of at least 10 feet per second and simultaneously with the maintaining of said compressive force to apply ultrasonic mechanical rubbing vibrations substantially parallel to the terminal portion of said blood vessels in a direction so as to apply an additional energy producing force to obtain a localized heating of the terminal portion, the direction of said mechanical vibrations being applied to produce shear waves at the terminal portion of said blood vessels, and said blood vessels, and said localized heating of the blood vessels is obtained by the conversion of said shear waves into heat, whereby said superfical cauterization is produced at least in part by the production of said shear waves, and E. continuing the retaining of said tool member in a position relative to said severed blood vessels and the application of said mechanical rubbing vibrations for a period of time sufficient for said localized heating to form a superfical cauterization at the terminal portion, whereby the terminal portion is closed off and the blood contained therein is prevented from escaping.

2. A method as claimed in claim 1, wherein said localized heating is also obtained by simultaneously inducing frictional rubbing at said terminal portion of said blood vessel by the application of said mechanical vibrations, whereby said cauterization is produced at least in part by said frictional heating.

3. A method as claimed in claim 1, wherein said blood vessel is relatively small in diameter and said cauterization is substantially formed by clotting of the blood at said terminal portion thereof.

4. A method as claimed in claim 1, wherein said cauterization is at least in part formed by a blood clot, and said localized heating expedites the formation of said blood clot.

5. A method as claimed in claim 1, wherein said cauterization is formed by partially closing the blood vessel by said localized heating and the remainder by clotting thE blood contained in said reduced area of the blood vessel.

6. A method as claimed in claim 1, wherein said mechanical vibration produces a plastic flow of the wall of said blood vessel and said flow is continued for a period of time sufficient to obtain a joining of the wall of said blood vessel to form said closure.

7. A method as claimed in claim 1, wherein said blood vessel is a capillary.

8. A method as claimed in claim 1, wherein said blood vessel is an arterial.

9. A method as claimed in claim 1, wherein said blood vessel is a veinule.

10. A method as claimed in claim 1, wherein said blood vessel is an artery.

11. A method as claimed in claim 1, wherein said blood vessel is a vein.

12. A method as claimed in claim 1, wherein said ultrasonic mechanical vibrations are applied over and area to simultaneously close off a plurality of blood vessels.

13. A method of superfically cauterizing severed blood vessels of a wound in vivo, with the aid of a noncutting spatula like tool member having a working surface, comprising the steps of A. applying the working surface of said tool member against the terminal portion of said blood vessels, said tool member being at substantially room temperature, B. retaining said tool member in a position relative to said severed blood vessels, C. maintaining a compressive force applied along a line substantially perpendicular to the plane defined by the terminal portion of said blood vessels with said noncutting spatula like tool member, D. simultaneously vibrating the working surface of said tool member, at a peak velocity of at least 10 feet per second and, while maintaining said compressive force, in a direction and at an ultrasonic rate to transmit mechanical vibrations to the terminal portion, said localized heating is obtained by inducing friction rubbing at the terminal portion of said blood vessels by the application of said mechanical vibrations, and E. continuing the retaining of said tool member in a position relative to said severed blood vessels and the application of said compressive force and mechanical vibrations until a superfical cauterization at said terminal portion is formed, whereby the blood contained therein is prevented from escaping.

14. A method as claimed in claim 13, further including the step of controlling the rate of frictional heating of the terminal portion of said blood vessel.

15. A method as claimed in claim 14, wherein said rate of frictional heating is controlled by texturing said toolworking surface to a surface roughness selected in accordance with the ultrasonic rate of vibration and compressive force to be applied.

16. A method as claimed in claim 13, wherein the application of said mechanical vibrations also simultaneously produce at least in part shear waves at said terminal portion, and the frequency and amplitude of vibration of said tool member is selected at a level wherein said transmitted shear waves are substantially maintained at the terminal portion with only superficial penetration and heating of the remainder of said blood vessel.

17. A method as claimed in claim 13, wherein said peak velocity is in the range of approximately 40 feet per second to 100 feet per second.

18. A method as claimed in claim 13, wherein said working surface is vibrated in an elliptical pattern.

19. A method as claimed in claim 13, wherein said mechanical vibrations are produced by vibrating the tool member to obtain longitudinal vibrations along said working surface, which working surface is maintained along a plane substantially parallel to the plane defined by the terminal portion of said blood vessel.

20. A method as claimed in claim 13, wherein said tool working surface is of sufficient area to simultaneously cauterize respective terminal portions.

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