Abstract:
A needle device for the delivery of medicaments, insuflation or other medical devices, having a reciprocable needle sensitive to lack of resistance, whereupon such needle retracts, permitting a cannula therewith to provide access to the penetrated body.

Description:
This application is a Divisional of Ser. No. 08/643,470 filed May 6, 1996 now U.S. Pat. No. 5,827,221; which is a Continuation of Ser. No. 08/361,982 filed Dec. 22, 1994 now U.S. Pat. No. 5,514,111; which is a Divisional of Ser. No. 08/057,354 filed May 3, 1993 now U.S. Pat. No. 5,376,082; which is a Continuation-In-Part of Ser. No. 07/788,253 filed Nov. 5, 1991 now U.S. Pat. No. 5,207,647. 
    
    
     BACKGROUND OF THE INVENTION 
     (1) Field of the Invention 
     This invention relates to needle devices, and more particularly to medical devices for introducing a needle and/or catheter into a body cavity a patient. 
     (2) Prior Art 
     The present application incorporates by reference my co-pending application, Ser. No. 07/788,253, filed Nov. 5, 1991 no U.S. Pat. No. 5,207,647. 
     A veress needle has a hollow, blunt inner needle, spring loaded, within a larger piercing cannula, to permit entry into a body space without laceration of obdominal structures. Several patents which disclose such devices are as follows: 
     U.S. Pat. No. 5,139,485 to Smith et al, which shows a spring loaded with an acoustic alarm to indicate passage of the needle into a space in a body. 
     U.S. Pat. No. 5,104,381 to Gresl et al, with a viewable indicator on a stylet to indicate penetration. 
     U.S. Pat. No. 5,098,388 to Kulkashi et al, having a porthole for receiving a fluid coupling permitting fluid to be passed into the needle. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a needle device which, when cocked, permits penetration of its distal tip into a body until it senses a space or void. The tip, which is a needle, is then retracted automatically and locked within the device, preventing further cutting capabilities of that trocar. 
     The present invention comprises a needle device having an elongated housing. The housing has a proximal and a distal end. An opening is arranged through the proximalmost end of the housing. A carriage shaft is disposed within the housing and extends slightly outwardly of the proximal opening. 
     An elongated cannula is attached to the distal end of the housing through a hub. The distalmost end of the cannula has a tip thereon. A needle is slidably disposed through the cannula. The distal end of the needle has a pointed tissue piercing tip. The proximal end of the needle (or trocar) is engaged with a detent assembly arranged at the distal end of the carriage shaft. The needle is hollow, allowing an endoscope (fiber optic camera) or other device to be place therethrough. 
     A first compressive spring is arranged within the housing to provide a proximally directed bias onto the carriage shaft. A second compressive spring is arranged within the housing, about the proximal end of the needle, but which spring has less force than the first spring. The distal end of the second spring keeps a forwardly or distally directed bias upon a flange on the needle. The proximal end of the second spring engages the distal end of the carriage shaft. The needle has a proximally extending finger or link which engages a detent assembly. The link rotates the detent assembly to effectuate rearward retraction of the carriage shaft and the needle with respect to the housing. 
     A valve in the proximal end of the cannula or catheter, is coaxial therewith, and is disposed within a cap and base assembly. Opon removal of the needle from the catheter, the cap and base assembly can be rotated with respect to one another, to open or close the valve therein. 
     The housing can be removed from the cannula/hub assembly to permit valvable access to the body space through the cannula. A stopcock is attached to the hub assembly to permit insuflation of a patient through the cannula. Insuflation is the pumping of carbon dioxide into a body (peritoneal) cavity to distent the fascis skin. 
     In operation of the present invention, the needle device is initially cocked by the attending physician, by pressing upon the proximalmost end of the carriage shaft. This causes the detent assembly to become engaged with the carriage shaft and compresses the first spring. The needle is also caused to extend outwardly slightly beyond the distal end of the cannula, causing the exposure of the cutting tip of the needle. 
     Penetration of skin, tissue and ligaments by gently force applied to the device into a patient, causes a slight rearward pressure and movement on the needle, simultaneously compressing the second spring and causing the link to move to a position that upon any forward motion of the needle link assembly, the link will rotate the detent assembly and thus release the carriage. 
     Upon entry of the needle into the body space, the needle is advanced distally very slightly by bias of the second spring thereagainst. This slight forward or distal advance of the needle causes the link attached to it to trip the detent assembly, thus releasing the carriage shaft from capture, whereupon the first, more powerful spring pushes the carriage shaft and attendently attached needle rearwardly or proximally, with an audible sound. This causes the needle to also be retracted proximally within the cannula. The proximal end of carriage shaft is also caused to extend out through the opening in the proximal end of the housing, to provide a visual indication of penetration into the body space, as well as the audible indication of such entry. A bore extends longitudinally through the carriage shaft, and is in communication with the bore in the needle. An optical device such as an endoscope, or a medicament supply may be disposed within such bore to permit visualization of the puncture and body organ and/or supply of medicaments therein. 
     Dissassembly of the cannula from the housing and opening of the bore of the catheter permits delivery of medicaments or other medical devices. The valve could be closed to close the bore through that cannula. A valved side port through the base permits the valve at the proximal end of the cannula to be closed (or open) while permitting supply of medicaments therethrough simultaneously with optics or other medicaments being disposed through the valve in the base. 
     It is apparent that this device may also be used to locate/enter other spaces or potential spaces in the body where there is less resistance than in the surrounding tissue, such as with the pneumothorax needles, drainage of absesses or the like. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The objects and advantages of the present invention will become more apparent when viewed in conjunction with the following drawings, in which: 
     FIG. 1 is a side elevational view insection of an veress needle device in a “packaged” configuration; 
     FIG. 2 is a view similar to FIG. 1, showing the veress needle device in its “cocked” configuration; 
     FIG. 3 is a view similar to FIG. 1, showing the veress needle device during penetration of tissue; 
     FIG. 4 is a view similar to FIG. 1, showing the veress needle device just as it enters an open space; 
     FIG. 5 is a view similar to FIG. 1, showing the veress needle device after it has entered the epidural space; 
     FIG. 6 is a view of the needle device being removed from its catheter tip; 
     FIG. 6A is a perspective view of a detent assembly arranged within the housing of the veress needle; 
     FIG. 7 is an enlarged longitudinal sectional view of the hub, base and cannule in a valve open orientation; 
     FIG. 8 is an enlarged longitudinal sectional view of the hub, base and cannula in a valve closed orientation; 
     FIG. 9 is a perspective view of the valve member which rotatively mates with the base; 
     FIG. 10 is an enlarged longitudinal sectional view of the catheter cap; 
     FIG. 11 is an enlarged longitudinal sectional view of the catheter base; 
     FIG. 12 is a view taken along the lines XII—XII of FIG. 8, with the needle removed and the valve closed; and 
     FIG. 13 is a view taken along the lines XIII—XIII of FIG. 7, and the valve opened. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings in detail, and particularly to FIG. 1, there is shown a veress needle device  10 , having an elongated housing  12  having a proximal end  14  and a distal end  16 . A proximal opening  18  is arranged through the proximal end  14  of the housing  12 . A longitudinally slidable carriage shaft  20  is disposed within the housing  12 , and has a proximal end  22  which extends slightly outwardly of the proximal opening  18 , when the veress needle device is shown in its “packaged” or “shipping” configuration depicted in FIG.  1 . 
     An elongated cannula (or catheter)  24  is attached to the distal end  16  of the housing  12  through a mating cap  26 , shown in an enlarged sectional view in FIG.  10 . The cannula  24  has a tip  28  on its distalmost end. A tubular needle  30  extending from the distal end  16  the housing  12  is slidably disposed within the lumen of the cannula  24 . The needle  30  has a pointed tissue piercing tip  32  on its distalmost end. A discharge opening  33  is disposed proximally adjacent the tip  32 , the opening  33  being in fluid communication with a lumen  31  in the tubular needle  30 . A base  27  is arranged on the proximal end of the cannula  24 . The base  27  has a central bore  104  which extends longitudinally therethrough and is in communication with the lumen  31  in the needle  30 . A side valve  29  is attached to the side of the base  27  and is in fluid communication through a channel  106  with the bore  104 , as shown in FIG.  11 . 
     The needle  30  has a proximal end  34  which extends into the distal end  16  of the housing  12  and which slidably engages a tapered channel  36  in a flange  38  on the distal end of the carriage shaft  20 , which is adapted to facilitate engagement and disengagement of a detent assembly  40 , shown more clearly in FIG.  6 A. 
     A first compressive spring  42  is arranged within the housing  12  between an abutment  44  therein disposed about the carriage shaft  20  and an annular flange  46  secured to the carriage shaft  20  near its proximal end  22 . The first compressive spring  42  provides a rearward or proximally directed bias onto the carriage shaft  20 . A longitudinal bore  41  extends through the carriage  20 , and is in fluid communication with the bore  31  of the needle  30 . 
     A notch  48  is arranged transversely about the mid-point of the carriage shaft  20 , as shown in FIG.  1 . 
     A second compressive spring  52  is disposed about a portion of the proximal end  34  of the needle  30 . The second spring  52  has a distal end which abuts an annular flange  54  which is disposed about the approximate mid-point of the needle assembly  30 . The second spring  52  has a proximal end which is in abutting engagement with the distalmost end of the carriage shaft  20  and the flange  38  thereon. An elongated resilient finger or link  56  is attached to the flange  54  and extends rearwardly therefrom. The link  56  has a “J” shaped distalmost tip  58  which engages the detent assembly  40 . A “U” shaped clip  53  has an end which engages the flange  38  and another end which acts as an abutment to the flange  54 , this other end slidably receiving the needle therethrough. 
     The detent assembly  40 , shown more explicitly in FIG. 6A, comprises a pivot hub  60  which is pivotably secured to an inside wall of the housing  12 . The pivot hub  60  is of generally cylindrical configuration and has an an axial post, not shown, on which a spring leg  62  is fixed. The leg  62  has a distal toe  64  arranged at a right angle thereto. The toe  64  is arranged to engage the notch  48  on the carriage shaft  20 . A release flange  66  extends from the proximal end of the leg  62 , as shown in FIG.  7 . The tip  58  of the link  56  is juxtaposed to engage and pull on the release flange  66  so that the toe  64  is pivoted from the notch  48 , thus releasing the carriage shaft  20 , in a manner describrd hereinbelow.  50  adjacent the shoulder  48  of the carriage shaft  20 . 
     The distalmost tip  58  of the link  56  is arranged to mate with the toe  64  and give it a slight “pull” to cause it to rotate (counter clockwise as shown in the drawings) so as to lift the toe flange  64  from the notch  48  in the carriage shaft  20 . 
     The cannula  24  has the mating cap  26  on its proximal most end, as shown in FIGS. 1-6. The cap  26 , has a tapered central bore  86 , which slidably mates with a tapered projection  86  on the distal end  16  of the housing  12 . The cap  26  has an opening  90  at the distal end of the bore  86 . An annular wall  92  defines the side perpheral surface of the cap  26 . An angular array of gear teeth  94  are disposed on the inner perpheral surface of the distal end of the annular wall  92 , as shown in FIG.  10 . 
     A base  27 , shown in FIGS. 1-6, but shown more clearly in section, in FIG. 11, comprises an annular wall  100  having a disc  102  molded adjacent its proximal end. The disc  102  has a central bore  104  arranged therethrough. A channel  106  is arranged through the wall  100  and is in communication with the bore  104 . A pivot axis  108  extends proximally off of the disc  102  between the wall  100  and the bore  104 . 
     An elongated valve member  110 , shown in cross-section in FIGS. 1-6, is shown in perspective in FIG. 9, has an opening  112  across one end thereof, which mates on the pivot axis  108  off of the disc  102  on the base  96 . The valve member  110  has an arrangement of gear teeth  114  on one end adjacent its opening  112 . The valve member  110  has an arrangement of gear teeth  114  on one end adjacent its opening  112 . The valve member  110  has a circular second opening  116  on the other end thereof, the second opening being of a diameter similar to the opening  90  in the cap  26  and the central bore  104  in the base  27 . The needle  30  is sized to slide through each of these openings when they are in longitudinal alignment, as is the case shown in FIG.  10 . 
     In assembly of the cannula  24 , the valve member  110  is mounted with its first end opening  112  on the pivot axis  108 . The cap  26  then fits against the disc  102  with the distal lip of its walls  92  mating within the proximal lip of the walls  100  of the base  27 , with the bore  90  in alignment with the second end opening  116  of the valve member  110  and the bore  104  of the base  27 . The teeth  114  of the valve member  110  are engaged with the teeth  92  on the inner distalmost lip of the wall  92  of the cap  26 . Once the needle  30  has been removed from the catheter  30 , the valve member  110  may be arcuately pivoted about pivot axis  108  on the cap  27  by rotation of the cap  26  therewith, because of the interengagement of the gear teeth  114  and  94  therebetween. Such a movement of the valve member  110  is shown in FIGS. 12 and 13, where FIG. 12 indicates the position of the valve member  112 , now closed, once the needle  30  has been withdrawn from the aligned openings  90 ,  116 , and  104 . 
     The side valve  29 , shown in FIGS. 1-6, mates with the channel  106  in the base  96  to permit fluid communication with the bore  104  and the canulea  24 , once the needle  30  has been withdrawn therefrom, permitting access to the body cavity therewith. 
     In operation of the needle device  10  the attending physician “cocks” it from its “packed” state shown in FIG. 1 to its “cocked” state by pressing the proximal end  22  of the carriage shaft  20  distally, or to the right, as shown in FIG. 2, thereby compressing the first spring  42  and bringing the notch  50  into mating engagement with the flange  72  of the outwardly biased U-shaped spring  64 . The tip  32  of the needle  30  is also at this time, once the device  10  has been cocked, to be caused to extend about 2 mm. beyond the distalmost end of the cannula tip  28 , and simultaneously permitting the cutting portion of the needle assembly  30  to be distally exposed. 
     Gentle but constant pushing force by the physician on the needle device  10  penetrates the patient&#39;s skin, soft tissue and ligaments, and causes the needle assembly  30  including the link  56 , to be pushed-back into the catheter  24  slightly, (to the left) as shown in FIG. 3, and also compressing the second compressive spring  52  slightly, and moving the tip  58  of the link  56  proximally past the pivot hub  60 . 
     Upon entering a body cavity the needle  30  encounters less resistance, and is therefore caused to advance slightly, for this example about 0.25 mm. because of its forward (distally directed) bias from the second compressive spring  52  acting upon the annular flange  54  secured thereto, the needle  30  being shown thusly in FIG.  4 . The distal tip  58  of the link  56  mates with the toe  64  extending off of the hub  60 . 
     As the needle  30  advances for example, about 0.25 mm. upon meeting with sudden diminished resistance upon entering the epidural space it also causes the link  56  to advance forwardly a corresponding amount. The frontwardly moving (distal) end  58  of the link  56  having been engaged with the release flange  66  of the pivot hub  60 , causes the pivot hub  60  to rotate slightly, about its axis of rotation “R”, counter-clockwise as shown in the drawings, to cause the rotation of the leg  62  as well, lifting the toe flange  64  out from locking engagement in the notch  48  of the carriage shaft  20 , as indicated by the arrow “O” in FIG.  4 . 
     The first compressive spring  42 , being stronger than the second compressive spring  52  is thus released, so as to push the carriage shaft  20  rearwardly, or the left, as shown in FIG. 4, by an arrow “L”, this occurring with an audible click, as the flange  46  hits the proximal wall of the housing  12 , the spring  42 , as shown in FIG. 5, by the pushing of the proximal end  22  of the carriage shaft  20  out of the proximal opening  18  in the housing  12 . During the rearward travel of the carriage shaft  20 , the needle assembly  30  to which the carriage shaft  20  is engaged, is also pulled proximally (rearwardly) by the first compressive spring  42 , as depicted in FIG.  5 . 
     Upon the encountering of the void or epidural space, the needle  30  no longer feels the resistance to its advance and retracts as aforementioned. 
     FIG. 6 shows the housing  12  and its enclosed/attached needle  30  being removed from the cannula  24 , to facilitate delivery of medicaments (or other catheters or medical devices) through the cannula  24  after the distal end of the needle  30  has been removed therefrom. Additionally, the cannula  24  itself,  28  could also be directed further into the body duct. 
     The valve member  110 , as aforementioned, can then be closed to await need for re-opening of the cannula  24  for introduction of a medical device such such as an endoscope, or fluid therethrough. The valve  110  could be replaced by a duckbill valve or a soft, penetrable material with a slit therethrough, not shown. The side valve  120  in the hub assembly also permits supplemental fluid introduction capabilities through the cannula  24  also. 
     Thus, what has been shown and described is a unique needle device suitable particularly for veress-type procedures, which permits single handed advance into body tissue, and when the needle (trocar) upon entering an body space and sensing no resistance to further forward advance, minutely advances on its own, well within distance limitations of small body space, only to trigger its own immediate retraction, removing the cutting and piercing component from exposure, presenting to that space a cannula tip for subsequent adaptation to a medical device on medicament supply source upon removal of the needle (trocar) and drive assembly from the cannula shaft.