Abstract:
A multi-lumen needle and catheter guidance system is provided and includes: a multi-lumen needle including a pair of rectangular lumens, the pair of rectangular lumens extending longitudinally within and through a shaft of the multi-lumen needle from a proximal end of the multi-lumen needle to a distal end of the multi-lumen needle, the pair of rectangular lumens diverging in opposite directions and ending at a pair of rectangular apertures formed on opposing sides of the distal end of the multi-lumen needle; and a pair of rectangular catheters for insertion into and through the pair of lumens, wherein distal ends of the rectangular catheters are configured to pass out of the distal end of the multi-lumen needle in opposing directions through the pair of rectangular apertures.

Description:
TECHNICAL FIELD 
       [0001]    The present invention is directed to medical devices. More particularly, the present invention is directed to a multi-lumen needle and catheter guidance system. 
       RELATED ART 
       [0002]    Pregnancy labor is characterized by regular, painful uterine contractions that increase in frequency and intensity and are associated with progressive cervical effacement and dilatation. 
         [0003]    Labor has been divided into three stages. The first stage occurs from onset of cervical change to 10 cm dilatation. It can be divided into latent and accelerative phases. The latent phase can last up to 8 hours, while the accelerative phase is associated with a faster rate of cervical dilatation and usually begins at 2-4 cm dilatation and the duration varies from 2 to 6 hours. 
         [0004]    The second stage occurs from full cervical dilatation (10 cm) to delivery of the baby. The third stage begins right after the birth of the baby and ends with the delivery of the placenta. 
         [0005]    Pain during the first stage of labor is due to uterine contractions and stretching of the cervix. It is cramping and visceral in nature, diffuse and poorly localized. Sensations are carried through primary afferent fibers which pass sequentially through the inferior, middle and superior hypogastric plexus, the lumbar and lower thoracic sympathetic chain and end in rami communicantes associated with T10-L1 spinal nerves. 
         [0006]    During the late first and second stage of labor, somatic pain predominates, as a result of distension and traction on the pelvic structures, the pelvic floor and the perineum and is carried via the pudendal nerve. Unlike the visceral pain of the first stage, the pain is sharp and well localized, due mainly to less arborization and the faster conduction velocity in the sacral pathways. 
         [0007]    The experience of labor pain is different for each woman, and the different methods chosen to relieve pain depend upon the techniques available locally and the personal choice of the individual. Two common pain relief methods include a lumbar epidural block and a caudal epidural block in which anesthetic compounds are introduced into different areas of the epidural space. 
       SUMMARY  
       [0008]    Embodiments of the invention are directed to a multi-lumen needle and catheter guidance system. The invention can be used, for example, for administration of compounds (e.g., anesthetic compounds) into the epidural space of a patient. In an embodiment, one catheter may be guided in a first direction (e.g., cranially) by the multi-lumen needle to provide a lumbar block, while another catheter may be guided by the multi-lumen needle in a second, opposite direction (e.g., caudally) to provide a caudal block. This allows one needle stick in the patient&#39;s back to achieve both blocks. 
         [0009]    One aspect of the invention is directed to a multi-lumen needle and catheter guidance system, comprising: a multi-lumen needle including a pair of rectangular lumens, the pair of rectangular lumens extending longitudinally within and through a shaft of the multi-lumen needle from a proximal end of the multi-lumen needle to a distal end of the multi-lumen needle, the pair of rectangular lumens diverging in opposite directions and ending at a pair of rectangular apertures formed on opposing sides of the distal end of the multi-lumen needle; and a pair of rectangular catheters for insertion into and through the pair of lumens, wherein distal ends of the rectangular catheters are configured to pass out of the distal end of the multi-lumen needle in opposing directions through the pair of rectangular apertures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings in which like references denote similar elements. 
           [0011]      FIG. 1  depicts a multi-lumen needle and catheter guidance system according to embodiments. 
           [0012]      FIG. 2  depicts a proximal end of the multi-lumen needle of  FIG. 1  according to embodiments. 
           [0013]      FIG. 3  depicts a distal end of the multi-lumen needle of  FIG. 1  according to embodiments. 
           [0014]      FIG. 4  depicts the insertion of catheters into the multi-lumen needle of  FIG. 1  according to embodiments. 
           [0015]      FIGS. 5 and 6  depict the exiting of catheters from the multi-lumen needle of  FIG. 1 . 
           [0016]      FIG. 7  depicts an operational view of the multi-lumen needle system and catheter guidance system of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    The invention is a multi-lumen needle and catheter guidance system. In embodiments, the invention can be used, for example, for administration of compounds (e.g., anesthetic compounds) into the epidural space of a patient. However, one skilled in the art would recognize that the multi-lumen needle and catheter guidance system of the invention may also be used to provide venous access, arterial access, or access to other cavities or spaces inside a body, for the administration of compounds or for other purposes. 
         [0018]    As depicted in  FIG. 1 , embodiments of the multi-lumen needle and catheter guidance system of the present invention include a multi-lumen needle  10  and at least one catheter  12 . The multi-lumen needle  10  may be provided with a plurality of lumens  14 A,  14 B. Although more than two lumens  14 A,  14 B may be provided in various embodiments, the description below will be directed to a multi-lumen needle  10  having a first lumen  14 A and a second lumen  14 B. However, the functionality of the multi-lumen needle and catheter guidance system of the present invention can easily be extended to accommodate more than two lumens and associated catheters. The lumens  14 A,  14 B serve to guide respective catheters  12 A,  12 B ( FIGS. 4-6 ) for insertion into and through the multi-lumen needle  10  and into the body of a patient. 
         [0019]    The lumen  14 A extends longitudinally through a shaft  16  of the multi-lumen needle  10  from approximately a proximal end  18  of the multi-lumen needle  10  to approximately a distal end  20  of the multi-lumen needle  10 . Similarly, the lumen  14 B extends longitudinally through the shaft  16  of the multi-lumen needle  10  from approximately the proximal end  18  of the multi-lumen needle  10  to approximately the distal end  20  of the multi-lumen needle  10 . Flanges  22  are provided near the proximal end  18  of the multi-lumen needle  10  to allow the multi-lumen needle  10  to be grasped, positioned, and manipulated. A portion  24 A of the lumen  14 A and a portion  24 B of the lumen  14 B may extend outside of the shaft  16  of the multi-lumen needle  10  at the proximal end  18  of the multi-lumen needle  10 . The portions  24 A,  24 B of each lumen  14 A,  14 B that extend outside of the shaft  16  of the multi-lumen needle  10  may be color coded and/or may include other identifying indicia to assist in differentiating between the lumens  14 A,  14 B. 
         [0020]    As illustrated in greater detail in  FIG. 2 , the lumens  14 A,  14 B may be separated from each other within the shaft  16  of the multi-lumen needle  10 . Each lumen  14 A,  14 B may extend longitudinally through the shaft  16  of the multi-lumen needle  10  from approximately the proximal end  18  of the multi-lumen needle  10  to approximately the distal end  20  of the multi-lumen needle  10 . In embodiments, separate lumens  14 A,  14 B may be provided and positioned such that adjacent side walls of the lumens  14 A,  14 B separate the lumens  14 A,  14 B at least along the length of the shaft  16  of the multi-lumen needle  10 . A single lumen with a center divider  26  may also be used to form and separate the lumens  14 A,  14 B. The lumens  14 A,  14 B may be configured to have the same opening shape and size as depicted in  FIG. 2 , or may be configured to have different opening shapes and/or sizes. 
         [0021]    In embodiments, as depicted in  FIG. 1 , the lumens  14 A,  14 B run parallel to each other and parallel to the longitudinal axis of the shaft  16  of the multi-lumen needle  10 . As the lumens  14 A,  14 B approach the distal end  20  of the multi-lumen needle  10 , the lumens  14 A,  14 B diverge from each other in different (e.g., opposing) direction and terminates at a corresponding aperture  28 A,  28 B formed through the sidewalls of the shaft  16  of the multi-lumen needle  10 . To this extent, the lumens  14 A,  14 B exit the shaft  16  of the multi-lumen needle  10  oriented in different (e.g., opposite) directions. An enlarged view of the apertures  28 A,  28 B is shown in  FIG. 3 . In other embodiment, more than two apertures may be present in the multi-lumen needle  10 . 
         [0022]    The distal end  20  of the multi-lumen needle  10  may be shaped such that it substantially comes to a point to foster penetration through the skin, fascia, dura, or other soft tissue of a patient. In embodiments, the shape of the distal end  20  of the multi-lumen needle  10  may be conical, “bullet” shaped, beveled, and/or the like. A non-limiting example of a shape of the distal end  20  of the multi-lumen needle  10  is depicted in  FIG. 3 . 
         [0023]    In embodiments, the multi-lumen needle  10  may be fabricated from a biocompatible metal, but it may also be fabricated from a polymer, ceramic, or composite material. The multi-lumen needle  10  may also include features that foster handling and manipulation during insertion. This may include a handle on the proximal end  18  of the multi-lumen needle  10 , or other features to enhance manipulation of the multi-lumen needle  10  by the a user, such as traction grooves. The multi-lumen needle  10  may also have depth indicators  13  to foster identification of its depth of penetration. The multi-lumen needle  10  may also have connections  15  on the distal end of each lumen  14 A,  14 B to interface with tubing or syringes, such as a Luer lock connection, tapered connection, or other connection to facilitate connection with syringes or tubing. The multi-lumen needle  10  may be of any suitable length or size. For instance, the multi-lumen needle  10  may have a size of 14-17 French, but could also be larger or smaller for different applications. 
         [0024]    Each lumen  14 A,  14 B is specifically configured to facilitate the deployment of a corresponding catheter  12 A,  12 B ( FIGS. 4-7 ) toward and out of a corresponding aperture  28 A,  28 B in the distal end  20  of the multi-lumen needle  10 . For instance, as shown for example in  FIG. 2 , each lumen  14 A,  14 B may have a rectangular cross-section, with a major axis oriented transversely and a minor axis oriented axially. In other embodiments, the lumens  14 A,  14 B may also be square, ovoid, elliptical, round, or any other shape that fosters catheter deployment. In the illustrated embodiment, the aperture  28 A is located at an angle of approximately 180 degrees from the aperture  28 B. One skilled in the art should recognize the apertures  28 A,  28 B at the distal end  20  of the multi-lumen needle  10  may be oriented at any relative angle. 
         [0025]    In embodiments, as depicted in  FIGS. 4-7 , the configuration of the lumens  14 A,  14 B, together with the orientation and shape of the apertures  28 A,  28 B and the configuration of the catheters  12 A,  12 B, helps to direct each catheter  12 A,  12 B in a specific direction (e.g., cranially and caudally) away from the distal end  20  of the multi-lumen needle  10 . In embodiments, each catheter  12 A,  12 B may have a cross-sectional shape that matches the cross-sectional shape of a corresponding lumen  14 A,  14 B. For example, if a lumen  14 A,  14 B has a rectangular cross-section, then each catheter  12 A,  12 B may also have a rectangular cross-section (but would be of a smaller size such that the catheters  12 A,  12 B can be longitudinally displaced within a corresponding lumen  14 A,  14 B). This, for example, helps a catheter  12 A,  12 B follow the path of a corresponding lumen  14 A,  14 B in, through, and out of the multi-lumen needle  10 . The cross-sectional geometry of each catheter  12 A,  12 B may be uniform along the length of the catheter  12 A,  12 B or may be variable along its length, as long as the catheter  12 A,  12 B can pass within the cross-sectional geometry of the lumens  14 A,  14 B in the multi-lumen needle  10 . 
         [0026]    In embodiments, each aperture  28 A,  28 B may have a cross-sectional shape that matches the cross-sectional shape of a corresponding lumen  14 A,  14 B and/or catheter  12 A,  12 B. For example, if a lumen  14 A,  14 B and/or a catheter  12 A,  12 B has a rectangular cross-section, then each aperture  28 A,  28 B may also have a rectangular cross-section. The rectangular cross-section of the apertures  28 A,  28 B may be the same size as or larger than the rectangular cross-section of the lumens  14 A,  14 B. 
         [0027]    Referring now specifically to  FIG. 4 , the insertion of the catheters  12 A,  12 B into the multi-lumen needle  10  is shown. In particular, an end  30 A of the catheter  12 A and an end  30 B of the catheter  12 B may be inserted into a respective lumen  14 A,  14 B as indicated by arrow A. The end  30 A,  30 B of each catheter  12 A,  12 B has a geometry and a plurality of openings  32 A,  32 B that will be discussed in greater detail below. 
         [0028]      FIG. 5  illustrates the multi-lumen needle  10  after the catheters  12 A,  12 B have been inserted through the lumens  14 A,  14 B. As shown, the end  30 A,  30 B of each catheter  12 A,  12 B has passed outward through a corresponding aperture  28 A,  28 B in the distal end  20  of the multi-lumen needle  10 . Each catheter  12 A,  12 B can be manipulated independently to allow the end  30 A,  30 B of each catheter  12 A,  12 B to be selectively and independently positioned in a patient at a desired distance (or different distances) from the distal end  20  of the multi-lumen needle  10 . This allows, for example, the same or different compounds (e.g., anesthetic compounds) to be independently dispensed at different locations within a patient via a single multi-lumen needle  10 . Once the catheters  12 A,  12 B are suitably deployed within the patient, the multi-lumen needle  10  can be removed over the catheters  12 A,  12 B, thereby leaving the catheters  12 A,  12 B in place within the patient. 
         [0029]    In embodiments, as shown in  FIGS. 6 and 7 , after insertion of the multi-lumen needle  10  into the epidural space (ES) of a patient, the shaft  16  of the multi-lumen needle  10  may be oriented such that one aperture (e.g., aperture  28 A) is direct caudally, while another aperture (e.g., aperture  28 B) is directed cranially. In such a case, the catheter  12 A may be inserted into the lumen  14 A at the proximal end  18  of the multi-lumen needle  10  such that it passes through the shaft  16  and exits the distal end  20  of the multi-lumen needle  10  via the aperture  28 A. The end  30 A of the catheter  12 A is thus directed caudally through the aperture  28 A as indicated by arrow B. Similarly, the catheter  12 B may be inserted into the lumen  14 B at the proximal end  18  of the multi-lumen needle  10  such that it passes through the shaft  16  and exits the distal end  20  of the multi-lumen needle  10  via the aperture  28 B. The end  30 B of the catheter  12 B is thus directed cranially through the aperture  28 B as indicated by arrow C. 
         [0030]    The catheters  12 A,  12 B may have a cross-sectional geometry that facilitates their passage into and through the lumens  14 A,  14 A of the multi-lumen needle  10  and out of the apertures  28 A,  28 B formed in the distal end  20  of the multi-lumen needle  10 , without binding, kinking, or otherwise failing during passage. In embodiments, for example as depicted in  FIGS. 4 and 5 , the catheters  12 A,  12 B have a rectangular cross-section with a major axis oriented transversely and a minor axis oriented axially. In general, the cross-sectional geometry of the catheters  12 A,  12 B matches the cross-sectional geometry of the lumens  14 A,  14 B. This helps to foster deployment of the catheters  12 A,  12 B in opposite (e.g., cranial and caudal) directions as the catheters  12 A,  12 B pass through the apertures  28 A,  28 B formed in the distal end  20  of the multi-lumen needle  10 . In other embodiments, the cross-sectional geometry of the catheters  12 A,  12 B may be square, ovoid, elliptical, round, or any other geometry that fosters catheter deployment. 
         [0031]    In embodiments, for example as depicted in  FIG. 4 , each catheter  12 A,  12 B includes a respective lumen  34 A,  34 B, which runs the length of the catheter  12 A,  12 B and is oriented along the axial direction of the catheter  12 A,  12 B. The lumen  34 A is in fluid communication with the corresponding plurality of openings  32 A formed near the end  30 A of the catheter  12 A. Similarly, the lumen  34 B is in fluid communication with the corresponding plurality of openings  32 B formed near the end  30 B of the catheter  12 B. The openings  32 A,  32 B are provided on at least one side of the catheters  12 A,  12 B and may be oriented perpendicular to the direction of insertion of the catheters  12 A,  12 B into the epidural space of the patient. The openings  32 A,  32 B may have any suitable cross-sectional shape (e.g., circular, oval, etc.), and may be oriented in any suitable pattern to facilitate a uniform or non-uniform distribution and release of fluids into the epidural space. 
         [0032]    As depicted in  FIGS. 4-6 , the end  30 A,  30 B of each catheter  12 A,  12 B may be shaped such that it substantially comes to a point to foster passage through the skin, fascia, dura, or other soft tissue. The end  30 A,  30 B of each catheter  12 A,  12 B may, for example, be conical, “bullet” shaped, or have a beveled shape. In embodiments in which the catheters  12 A,  12 B do not need to penetrate through tissue, the ends  30 A,  30 B may be blunted. 
         [0033]    The catheters  12 A,  12 B may be fabricated from a biocompatible material such as a polymer or a metal. Ceramic or composite materials may also be used. The catheters  12 A,  12 B may be formed from a radiolucent material to allow visualization during insertion (e.g., using x-ray imagery). 
         [0034]    The interior, exterior, and/or walls of the catheters  12 A,  12 B can be reinforced or otherwise configured to facilitate the deployment and operation of the catheters  12 A,  12 B. For example, as depicted in  FIG. 6 , an element (e.g., a wound metal sleeve  40 ) may be provided along at least a portion of the length of the catheters  12 A,  12 B (e.g., extending up to about 6 cm from the ends  30 A,  30 B of the catheters  12 A,  12 B). In another embodiment, an element (e.g., a wire  42 ) may formed of a shape-memory alloy (e.g., copper-aluminium-nickel, nickel-titanium (NiTi), and/or the like) that “remembers” its original, cold-forged shape. The wire  42  may be provided along (e.g., embedded within) at least a portion of the length of the catheters  12 A,  12 B (e.g., extending up to about 6 cm from the ends  30 A,  30 B of the catheters  12 A,  12 B). In this case, the wire  42  can cause the catheters  12 A,  12 B to have a 90 degree curve prior to insertion into the multi-lumen needle  10 . The wire  42  is temporarily straightened as it passes though the multi-lumen needle  10 , returning to its original shape as it passes out of the multi-lumen needle  10  into a patient. In either case, the catheters  12 A,  12 B is compliant enough to bend as it follows the path of the lumens  14 A,  14 B in the multi-lumen needle  10 , but rigid enough so that it will not kink, buckle, or otherwise fail during passage through the multi-lumen needle  10  and into a patient. 
         [0035]    The foregoing description of various aspects of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously, many modifications and variations are possible. Such modifications and variations that may be apparent to an individual in the art are included within the scope of the invention as defined by the accompanying claims.