Patent Publication Number: US-2015080858-A1

Title: Catheter and method of making the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is related by subject matter to U.S. Pat. No. 8,409,169, filed on Jun. 18, 2010, the contents of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to medical devices, such as catheters, and particularly to enteral feeding catheters. 
     2. Description of the Related Art 
     Feeding-decompression catheters must reside within the gastrointestinal (G-I) tract of patients for prolonged periods. A catheter may be delivered by direct penetration through the abdominal and gastrointestinal walls. Some directly placed catheters may then be directed to traverse the normal G-I channels to reach a more distal duodenal or jejunal feeding and/or aspiration site. 
     Alternatively, the catheter may be introduced indirectly and less traumatically into the body through a natural opening (e.g., nasal passage), to then traverse the natural G-I channels to the gastric or intestinal feeding and/or aspiration site. As the catheter encounters sharp bends and makes prolonged contact, it may irritate sensitive tissue. The size of the nasal passage and ever increasing discomfort limit the maximum outside diameter (O.D.) of a useful nasal catheter to about 6.7 mm, or about 20 Fr (French) units, wherein 3 Fr units=1 mm. 
     Some catheters are single lumen catheters and others are dual lumen devices which include feeding and aspirating tubes. Such single and dual lumen catheters are disclosed in U.S. Pat. Nos. 3,618,613, 4,543,089, 4,642,092, 4,705,511, 4,806,182, 5,334,169, 5,520,662, 5,599,325, 5,676,659, 5,807,311, 5,947,940, 6,508,804, 6,659,974, 6,881,211, 6,921,396 and 6,949,092, the contents of which are incorporated entirely herein by reference. 
     The O.D. of all feeding devices must be minimized to reduce patient trauma and discomfort. The catheter must provide necessary clearances to accommodate feeding inflow and/or aspirate outflow, while also minimizing the likelihood of blockage. 
     The internal diameter (I.D.) of a feeding channel required to accommodate an adequate flow rate by gravity feed or by pump can be met easily. However, the adequacy of aspiration flow is less certain. The volume of aspirate to be removed fluctuates, and often exceeds many-fold the rate of feeding. Excess digestive juices and swallowed air that escape removal may be propelled downstream, to accumulate and cause distention. Further, the aspiration channel is at greater risk for occlusion by the particulates and mucus encountered in the gastrointestinal fluids. The I.D. of the aspiration channel, especially, must be maximized. 
     The enteral feeding catheter is used to provide patients with nourishment, utilizing the propulsion and absorption functions of the gastrointestinal tract. Adequate food nourishes the patients, accelerates healing, aids infection resistance, and decreases recovery time. However, G-I motility of hospitalized patients is characteristically impaired by disease and/or trauma, including the trauma incident to surgery. 
     An aspirating tube is positioned proximal to the feeding site to reduce abdominal distention, which occurs when air and excess fluids accumulate. The aim of this aspiration is to intercept all swallowed air, and also remove any inflowing liquid that exceeds the patient&#39;s capacity for outflow via peristalsis from the feeding site. The outer layer of the aspirating catheter must allow for inflow of fluid, between the coils of the spring band. If the inner skeleton (the spiral spring band) was overlaid with a layer of continuous plastic, multiple holes will have to be provided by punching, laser drilling, etc. 
     Abdominal distention exerts its harmful effects in several ways. It reduces the ability of the patient to adequately breathe deeply, cough and clear secretions, predisposing to pneumonia. It causes extreme discomfort and limits mobility. It interferes with nutrient absorption. The resulting undernourishment slows the healing process, reduces the patient&#39;s optimum resistance to infection, and increases the recovery time. 
     When a catheter is inserted via the nose, it bends to conform to the nasal passage, esophagus, etc. The bent catheter may kink, causing partial or total occlusion. This is prevented in standard catheters by increasing the thickness of the flexible wall. 
     One example of such a current feeding tube from CR Bard, Inc. is a gastrostomy catheter for direct placement into the stomach. It has an I.D. of 6 mm and an O.D. of 9.3 mm, or 28 Fr units. The wall thickness of 1.67 mm (5 Fr units) is designed to prevent kinking. A 28 Fr catheter is too large and uncomfortable to insert transnasally in a patient. The nasal catheters in current use are necessarily more slender, and therefore have lumens with compromised functionality. 
     Therefore, it is an object of the present invention to provide a catheter with an ultra-thin wall that is less likely to experience kinking in response to being bent. 
     BRIEF SUMMARY OF THE INVENTION 
     Embodiments of the present invention provide a catheter, and methods of manufacturing and using the catheter. 
     In one embodiment, a slender device that is both flexible and kink resistant is provided. The catheter is made of a thin wall, biocompatible plastic elastomer, such as but not limited to polyurethane, reinforced with a thin helical spring band, such as but not limited to a thin helical spring band of stainless steel. The total wall thickness of a 6 mm I.D. catheter made in accordance with the present invention can be less than about 1/30 th  of its O.D. 
     The reinforcing spring band may be made in two layers, as a double helix, with overlapping clockwise and counter-clockwise coils. Each of the plies will be less than half the thickness required by a single-layered spring for the same structural strength. 
     Simple liquid flow through a gastrointestinal catheter is generally proportional to the 4 th  power of the I.D. The likelihood of occlusion is not so easily defined, but may reach a similar (or greater) value under encountered circumstances. Even modest increase in the I.D. profoundly improves flow rate and occlusion resistance. 
     In another embodiment, a fine cloth mesh sleeve, such as, but not limited to polyester, nylon, or a mixture thereof, tightly encases the otherwise exposed distal helical spring band is utilized. The fine cloth mesh sleeve is generally about 0.002″ thick, This allows free inflow of the gastric and intestinal liquids surrounding that section of the catheter, and provide longitudinal stability. The impervious plastic layer will overlay the proximal portion of the spring band, with an approximately one inch of overlap to secure the cloth mesh sleeve in place. The terminal end of the sleeve can be secured to the terminal end of the spring band with adhesive or by other mechanical means. 
     In still another embodiment, this cloth mesh sleeve will encase the entire length of underlying helical spring band. An extremely thin layer, about 0.0025″ of heat shrinkable polyester or polyolefin tubing can be applied to overlay the proximal segment of the catheter, making it impervious to fluid. Heat shrink tubing usually imparts a relative inflexibility to the underlying material. By making this heat shrink tubing ultra-thin, adequate flexibility is achieved. However, this layer may be at risk for “cutting” by the underlying stainless steel spring band. The cloth mesh sleeve between the heat shrink tubing and spring band would protect the former while minimizing the thickness. 
     The novel features of these embodiments are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view of a person with a catheter inserted therein, wherein the catheter includes a resilient tube and reinforcement member. 
         FIG. 2  is a side view of the catheter of  FIG. 1 . 
         FIGS. 3   a  and  3   b  are perspective and end views, respectively, of a portion of the resilient tube of  FIG. 1 . 
         FIGS. 4   a ,  4   b  and  4   c  are side, end and perspective views, respectively, of the reinforcement member of  FIG. 1  embodied as a helical spring. 
         FIG. 4   d  is a perspective view of a helical coil of the helical spring of  FIGS. 4   a ,  4   b  and  4   c.    
         FIGS. 5   a ,  5   b  and  5   c  are perspective, side and end views, respectively, of the reinforcement member of  FIG. 1  embodied as a helical reinforcement member. 
         FIG. 5   d  is a perspective view of a helical band coil of the helical reinforcement member of  FIGS. 5   a ,  5   b  and  5   c.    
         FIG. 5   e  is a sectional view of the helical reinforcement member of  FIGS. 5   a ,  5   b  and  5   c  taken along a cut-line  5   e - 5   e  of  FIG. 5   a.    
         FIG. 5   f  is a perspective view of another embodiment of a helical reinforcement member, which can be included with the catheter of  FIG. 1 . 
         FIG. 5   g  is a close-up perspective view of the helical reinforcement member of  FIGS. 5   a ,  5   b  and  5   c.    
         FIG. 5   h  is a cut-away side view of the helical reinforcement member of  FIGS. 5   a ,  5   b  and  5   c  taken along a cut-line  5   h - 5   h  of  FIG. 5   g.    
         FIG. 5   i  is a perspective view of the helical reinforcement member of  FIGS. 5   a ,  5   b  and  5   c  taken along cut-line  5   h - 5   h  of  FIG. 5   g.    
         FIG. 5   j  is a perspective view of the helical band coil of the helical reinforcement member of  FIGS. 5   a ,  5   b  and  5   c  having three arms connected thereto. 
         FIG. 5   k  is a perspective view of the helical band coil of the helical reinforcement member of  FIGS. 5   a ,  5   b  and  5   c  having four arms connected thereto. 
         FIG. 5   l  is a perspective view of another embodiment of a helical reinforcement member, which can be included with the catheter of  FIG. 1 . 
         FIG. 5   m  is a sectional view of the non-helical band coil of  FIG. 5   l  taken along a cut-line  5   m - 5   m  of  FIG. 5   l.    
         FIGS. 5   n  and  5   o  are perspective and side views, respectively, of another embodiment of a helical reinforcement member, which can be included with the catheter of  FIG. 1 . 
         FIG. 5   p  is a side view of another embodiment of a helical reinforcement member, which can be included with the catheter of  FIG. 1 . 
         FIG. 5   q  is a perspective view of another embodiment of a helical reinforcement member, which can be included with the catheter of  FIG. 1 . 
         FIGS. 6   a  and  6   b  are perspective and end views, respectively, of a non-helical reinforcement member, which can be included with the catheter of  FIG. 1 . 
         FIG. 6   c  is a perspective view of a non-helical band coil of the non-helical reinforcement member of  FIGS. 6   a  and  6   b.    
         FIG. 6   d  is a sectional view of the non-helical reinforcement member of  FIGS. 6   a  and  6   b  taken along a cut-line  6   d - 6   d  of  FIG. 6   a.    
         FIG. 6   e  is a close-up perspective view of the helical reinforcement member of  FIGS. 6   a  and  6   b.    
         FIG. 6   f  is a cut-away side view of the helical reinforcement member of  FIGS. 6   a  and  6   b  taken along a cut-line  6   f - 6   f  of  FIG. 6   e.    
         FIG. 6   g  is a perspective view of the helical reinforcement member of  FIGS. 6   a  and  6   b  taken along cut-line  6   f - 6   f  of  FIG. 6   e.    
         FIG. 6   h  is a perspective view of the non-helical band coil of the helical reinforcement member of  FIGS. 6   a  and  6   b  having three arms connected thereto. 
         FIG. 6   i  is a perspective view of the helical band coil of the non-helical reinforcement member of  FIGS. 6   a  and  6   b  having four arms connected thereto. 
         FIG. 6   j  is a perspective view of another embodiment of a non-helical band coil, which can be included with the catheter of  FIG. 1 . 
         FIG. 6   k  is a perspective view of another embodiment of a non-helical reinforcement member, which can be included with the catheter of  FIG. 1 . 
         FIGS. 7   a  and  7   b  are perspective and end views, respectively, of a resilient reinforcement member tube with a reinforcement member channel extending therethrough. 
         FIG. 7   c  is a perspective view of the resilient reinforcement member tube of  FIGS. 7   a  and  7   b  showing the helical reinforcement member of  FIGS. 5   a ,  5   b  and  5   c  in phantom. 
         FIG. 7   d  is a perspective view of the resilient reinforcement member tube of  FIGS. 7   a  and  7   b  showing the non-helical reinforcement member of  FIGS. 6   a  and  6   b  in phantom. 
         FIGS. 8   a  and  8   b  are perspective and end views, respectively, of a vacuum tube system, which is used to manufacture a catheter which includes a resilient tube and reinforcement member. 
         FIG. 8   c  is a cut-away side view of the vacuum tube system of  FIGS. 8   a  and  8   b  taken along a cut-line  8   c - 8   c  of  FIG. 8   a.    
         FIGS. 9   a  and  9   b  are cut-away side views of the vacuum tube system of  FIGS. 8   a  and  8   b  taken along cut-line  8   c - 8   c , wherein the resilient tube of  FIGS. 3   a  and  3   b  extends through the vacuum tube channel. 
         FIG. 9   c  is a cut-away side view of the vacuum tube system of  FIGS. 8   a  and  8   b  and the resilient tube of  FIGS. 3   a  and  3   b.    
         FIG. 9   d  is a cut-away side view of the vacuum tube system of  FIGS. 8   a  and  8   b , resilient tube  FIGS. 3   a  and  3   b  and reinforcement member of  FIGS. 5   a ,  5   b  and  5   c.    
         FIGS. 10   a  and  10   b  are perspective and end views, respectively, of a catheter, wherein the helical reinforcement member of  FIGS. 5   a  and  5   b  is shown as partially extending through the resilient tube of  FIGS. 3   a  and  3   b.    
         FIG. 10   c  is a close-up view of the catheter of  FIGS. 10   a  and  10   b.    
         FIGS. 11   a  and  11   b  are perspective and end views, respectively, of a catheter, wherein the non-helical reinforcement member of  FIGS. 6   a  and  6   b  is shown as partially extending through the resilient tube of  FIGS. 3   a  and  3   b.    
         FIG. 11   c  is a close-up view of the catheter of  FIGS. 11   a  and  11   b.    
         FIG. 12   a  is a side view of another embodiment of a catheter, which includes a non-helical reinforcement member, and a resilient tube having aspirating orifices. 
         FIG. 12   b  is a side view of the non-helical reinforcement member of  FIG. 12   a.    
         FIGS. 12   c  and  12   d  are perspective views of the resilient tube of  FIG. 12   a  looking in directions indicated in  FIG. 12   a.    
         FIGS. 13   a ,  13   b  and  13   c  are flow diagrams of methods of manufacturing a reinforcement member. 
         FIGS. 14   a  and  14   b  are flow diagrams of methods of manufacturing a catheter. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a front view of a person  100  with a catheter  110  inserted therein. It should be noted that catheter  110  can be used as many different medical devices, such as a feeding tube, aspirating tube, etc. Further, catheter  110  includes a single lumen in this embodiment, but it can include more than one lumen, if desired. An embodiment of catheter  110  which includes two lumens is often referred to as a dual lumen catheter. One example of a dual lumen catheter includes feeding and aspirating tubes, wherein the feeding tube extends through the aspiration tube. The feeding tube is positioned distal to but in close proximity (&lt;5 cm) to the end of the aspiration tube, but still within the same anatomical segment of the G-I tract, e.g the duodenum. More information regarding dual lumen devices can be found in the references cited in the Background. 
     In this embodiment, catheter  110  has been positioned so it extends through a nasal passage  101  of person  100  and esophagus  102  and into the gastrointestinal tract  103 . Catheter  110  extends between nasal passage  101  and gastrointestinal tract  103 , and is bent in a region  107  of person  100 . It should be noted that gastrointestinal tract  103  includes stomach  104  and intestines  105  of person  100 . Further, intestines  105  of person  100  include a duodenum  106   a  and jejunum  106   b . The proximal portion of catheter  110 , denoted as proximal portion  113   a , is proximate to nasal passage  101 . Further, the distal portion of catheter  110 , denoted as distal portion  113   b , extends through esophagus  102  and into gastrointestinal tract  103 . In particular, distal portion  113   b  extends into duodenum  106   a  or jejunum  106   b . As discussed in more detail below, catheter  110  is resistant to kinking when it is inserted through nasal passage  101  and esophagus  102  and into gastrointestinal tract  103 . 
       FIG. 2  is a side view of catheter  110 . In this embodiment, catheter  110  includes a connector  111  with a side-arm  111   a  connected to proximal portion  113   a , and a tip  112  connected to distal portion  113   b . Connector  111  allows catheter  110  to be operatively connected to a machine (not shown), such as a feeding or aspirating machine, and tip  112  retains portion  113   b  in gastrointestinal tract  103 . The machine controls the flow of material through catheter  110  and between nasal passage  101  and gastrointestinal tract  103 . In this way, catheter  110  is operatively connected to the machine. In this embodiment, the material includes gastric and intestinal juices and food. 
     As shown in  FIG. 2 , proximal portion  113   a  and distal portion  113   b  have lengths L 1  and L 2 , respectively. Lengths L 1  and L 2  can have many different values. For example, in one embodiment, length L 1  is between about eight inches to about fifteen inches, and length L 2  is between about thirty inches to about forty inches. It is desirable for proximal portion  113   a  to be able to extend through nasal passage  101  and esophagus  102  without kinking, such as in region  107  ( FIG. 1 ). Further, it is desirable for distal portion  113   b  to be allowed to bend, but limited stretching and compressing. 
     As will be discussed in more detail below, catheter  110  includes a resilient tube of material having a channel, and a reinforcement member which extends through the channel. The resilient tube extends between proximal portion  113   a  and distal portion  113   b . The length of the resilient tube is chosen so it can extend through nasal passage  101  and into gastrointestinal tract  103  ( FIG. 1 ). The resilient tube channel extends along the length of the resilient tube. Hence, the resilient tube channel extends through proximal portion  113   a  and distal portion  113   b.    
     The resilient tube can be manufactured in many different ways. For example, the resilient tube may be manufactured from a thin film of a polymer having an adhesive inner layer. Suitable thin film polymers. include, but are not limited to elastomers, such as polyurethane; polyester; and/or polyolefin. The width of the thin film polyurethane, for example, is slightly greater than the reinforcement member, or spring to be covered. A strip of the thin film polyurethane is secured to a first surface of the reinforcement member with the adhesive side up. The reinforcement member is placed lengthwise along one edge of the adhesive and rolled to enclose the spring with an impervious tube of the elastomer. 
     Alternatively, the spring can be secured on a rotating mandrill. The thin film elastomer having an adhesive layer can be applied as a spiral overlapping tube. 
     An extremely thin layer, generally in the range of from about 0.001″ to about 0.008″, more generally in the range of about 0.001″ to about 0.0025″ of the adhesive coated elastomer can be applied to overlay the proximal segment of the catheter, making it impervious to fluid. 
     The resilient tube can be manufactured by rolling flat pieces of resilient material into tubes as discussed above. The resilient tube can also be extruded. The resilient tube can be extruded in many different ways, such as those disclosed in U.S. Pat. Nos. 4,791,965, 4,888,146, 5,102,325, 5,542,937, 6,045,547, 6,165,166, 6,434,430, 6,692,804, 6,773,804 and 6,776,945, the contents of which are incorporated herein by reference. 
     The reinforcement member extends along the length of the resilient tube. In some embodiments, the reinforcement member extends through proximal portion  113   a  and not through distal portion  113   b . In other embodiments, the reinforcement member extends through distal portion  113   b  and not through proximal portion  113   a . In some embodiments, the reinforcement member extends through proximal portion  113   a  and distal portion  113   b.    
     The reinforcement member is allowed to bend. A reinforcement member is allowed to bend when it is allowed to move side-to-side. Further, a reinforcement member is allowed to bend when it is allowed to flex. A reinforcement member is restricted from bending when it is restricted from moving side-to-side. Further, a reinforcement member is restricted from bending when it is restricted from flexing. It should be noted that catheter  110  is bent in  FIGS. 1 and 2 . Further, the reinforcement member (not shown) of catheter  110  is bent in  FIGS. 1 and 2 . 
     The reinforcement member is allowed to bend so it can extend through nasal passage  101  and esophagus  102  and reduce the likelihood of the resilient tube being kinked. The flow of material through the resilient tube can be undesirably restricted when the resilient tube kinks. The reinforcement member is allowed to bend so it can extend through nasal passage  101  and esophagus  102  and reduce the likelihood of the resilient tube channel kinking. The flow of material through the resilient tube channel can be undesirably restricted when the resilient tube channel kinks. 
     In some embodiments of catheter  110 , the reinforcement member is restricted from stretching. A reinforcement member is restricted from stretching when its length is restricted from increasing. A reinforcement member is allowed to stretch when its length is allowed to increase. In some of these embodiments, the reinforcement member is restricted from compressing. The reinforcement member is restricted from compressing when its length is restricted from decreasing. The reinforcement member is allowed to compress when its length is allowed to decrease. 
       FIGS. 3   a  and  3   b  are perspective and end views, respectively, of a portion of a resilient tube  120 , which is included with catheter  110 . The portion of resilient tube  120  shown in  FIG. 3   a  can be the portion of resilient tube  120  extending through a region  114  of catheter  110 , which is shown in  FIG. 2 . Region  114  can be any portion of proximal portion  113   a . The portion of resilient tube  120  shown in  FIG. 3   a  can be the portion of resilient tube  120  extending through a region  115  of catheter  110 , which is shown in  FIG. 2 . Region  115  includes a portion of proximal portion  113   a  and distal portion  113   b . The portion of resilient tube  120  shown in  FIG. 3   a  can be the portion of resilient tube  120  extending through a region  116  of catheter  110 , which is shown in  FIG. 2 . Region  116  can be any portion of distal portion  113   b.    
     In this embodiment, resilient tube  120  has a tube channel  121 , and an outer resilient tube surface  122  and inner resilient tube surface  123 , all of which extend along its length. Inner resilient tube surface  123  faces tube channel  121  and outer resilient tube surface  122  faces away from tube channel  121 . It should be noted that outer resilient tube surface  122  and inner resilient tube surface  123  are annular surfaces which extend around tube channel  121 . Further, outer resilient tube surface  122  and inner resilient tube surface  123  are curved surfaces which curve around tube channel  121 . 
     The material of tube  120  is chosen so that resilient tube  120  can be stretched and compressed in a direction  128  in  FIG. 3   a , wherein direction  128  extends along the length of resilient tube  120 . The material of tube  120  is chosen so that resilient tube  120  can be bent, as indicated by direction arrows  126  and  127  in  FIGS. 3   a  and  3   b . It should be noted that directions  126  and  127  are perpendicular to each other, and directions  126  and  127  are perpendicular to direction  128 . 
     The material of tube  120  is chosen so that outer resilient tube surface  122  and inner resilient tube surface  123  are both collapsible in response to a force F 1  applied to outer resilient tube surface  122  ( FIG. 3   b ). It should be noted that a dimension d Tube  of channel  121  decreases in response to force F 1  being applied to outer resilient tube surface  122 . In this embodiment, dimension d Tube  corresponds to an inner diameter of tube channel  121 . Dimension d Tube  of channel  121  extends between opposed sides of inner resilient tube surface  123 . Dimension d Tube  can have many different values. In one embodiment, dimension d Tube  has a value in a range between about 0.100 inches to about 0.500 inches. 
     The material of resilient tube  120  can be of many different types, such as polyurethane, polysiloxane, and polyfluorohydrocarbons (“TEFLON”). It should be noted that resilient materials are often referred to as elastomers. Examples of materials which can be used in resilient tube  120  are disclosed in some of the patents referenced in the background of this application. It should also be noted that resilient tube  120  includes a single layer of resilient material in the shape of a tube. However, resilient tube  120  generally includes one or more layers of resilient material in the shape of a tube. 
     The resilient material is chosen so that outer resilient tube surface  122  and inner surface  123  are both stretchable in response to a force F 2  applied to inner resilient tube surface  123  ( FIG. 3   b ). It should be noted that dimension D Tube  of channel  121  increases in response to force F 2  being applied to inner resilient tube surface  123 . The resilient material is chosen so that outer resilient tube surface  122  and inner surface  123  are both repeatably moveable between stretched and unstretched conditions. 
     It is useful to be able to increase the value of dimension D Tube  so that the reinforcement member can be extended through resilient tube channel  121 , as will be discussed with  FIG. 9   c . Dimension D Tube  of channel  121  increases in response to force F 2  being increased and force F 1  being decreased. Dimension D Tube  of resilient tube channel  121  decreases in response to force F 2  being decreased and force F 1  being increased. It is useful to be able to decrease the value of dimension D Tube  so that inner resilient tube surface  123  can be moved towards the reinforcement member extending through resilient tube channel  121 , as will be discussed with  FIG. 9   d.    
     The reinforcement member of catheter  110  can be of many different types. For example, in some embodiments, the reinforcement member of catheter  110  is a helical reinforcement member and, in other embodiments, the reinforcement member of catheter  110  is a non-helical reinforcement member. 
       FIGS. 4   a ,  4   b  and  4   c  are side, end and perspective views, respectively, of a helical reinforcement member embodied as a helical spring  130  having a helical spring channel  131  extending therethrough. In this embodiment, helical spring  130  is allowed to bend in directions  126  and  127 , and to stretch and compress in direction  128 . Helical spring  130  has an outer dimension, which is denoted as dimension d Spring . In this embodiment, outer dimension d Spring  corresponds to the outer diameter of helical spring  130 . Dimension d Spring  can have many different values. In one embodiment, dimension d Spring  has a value in a range between about 0.100 inches to about 0.500 inches. In other embodiments, dimension d Spring  has a value in a range between about 0.200 inches to about 0.500 inches. 
     Helical spring  130  includes a number of helical coils  135 , wherein one helical coil  135  is shown in a perspective view of  FIG. 4   d . The helical coils of helical spring  130  are coupled together in a well-known manner so they operate as a spring. In particular, the helical coils of helical spring  130  are coupled together so helical spring  130  is allowed to compress, stretch and bend. In this way, the helical coils of helical spring  130  are coupled together so they operate as a spring. 
     It should be noted that outer dimension d Spring  corresponds to the outer diameter of helical coil  135 . It should also be noted that helical spring  130  generally includes a single elongate piece of material that has a helical shape. Hence, the helical coils of helical spring  130  can correspond to coils of the single elongate piece of material. 
     In this embodiment, helical coil  135  has a circular cross-sectional shape, as seen in  FIG. 4   d , and as indicated by an indication arrow  136 . Hence, the cross-sectional shape of helical coil  135  is not band-shaped. Examples of band-shaped helical coils will be discussed in more detail below. Helical spring  130  can be manufactured in many different ways, such as those disclosed in U.S. Pat. Nos. 4,302,959, 5,363,681, 6,006,572, 6,923,034 and 7,198,187. 
       FIGS. 5   a ,  5   b  and  5   c  are perspective, side and end views, respectively, of a helical reinforcement member  140 . As discussed in more detail below, helical reinforcement member  140  is allowed to bend in directions  126  and  127 , and is restricted from stretching and compressing in direction  128  ( FIG. 5   b ). Helical reinforcement member  140  has an outer dimension, which is denoted as dimension d Coil  in  FIG. 5   c . In this embodiment, outer dimension d Coil  corresponds to the outer diameter of helical reinforcement member  140 . Dimension d Coil  can have many different values. In one embodiment, dimension d Coil  has a value in a range between about 0.100 inches to about 0.500 inches. In other embodiments, dimension d Coil  has a value in a range between about 0.200 inches to about 0.500 inches. 
     As shown in  FIG. 5   c , helical reinforcement member  140  has a reinforcement member channel  141  extending therethrough, and an outer reinforcement member surface  142  and inner reinforcement member surface  143 . Inner reinforcement member surface  143  faces reinforcement member channel  141  and outer reinforcement member surface  142  faces away from reinforcement member channel  141 . It should be noted that outer reinforcement member surface  142  and inner reinforcement member surface  143  are annular surfaces which extend around reinforcement member channel  141 . Further, outer reinforcement member surface  142  and inner reinforcement member surface  143  are curved surfaces which curve around reinforcement member channel  141 . 
     In this embodiment, helical reinforcement member  140  includes a number of helical band coils  145   a ,  145   b ,  145   c ,  145   d  and  145   e , wherein helical band coil  145   a  is shown in a perspective view in  FIG. 5   d . Helical band coils  145   a ,  145   b ,  145   c ,  145   d  and  145   e  are coupled together so helical reinforcement member  140  has a helical shape. It should be noted that reinforcement member channel  141  extends through helical band coils  145   a ,  145   b ,  145   c ,  145   d  and  145   e . It should also be noted that the outer diameter of helical band coils  145   a ,  145   b ,  145   c ,  145   d  and  145   e  correspond to dimension d Coil . 
     In this embodiment, helical reinforcement member  140  includes a single elongate piece of material which has a helical shape. Hence, the helical band coils of helical reinforcement member  140  correspond to coils of the single elongate piece of material. 
       FIG. 5   e  is a sectional view of helical reinforcement member  140  taken along a cut-line  5   e - 5   e  of  FIG. 5   a . In particular,  FIG. 5   e  is a sectional view of helical band coil  145   d  taken along cut-line  5   e - 5   e  of  FIG. 5   a . In this embodiment, helical band coil  145   d  is band-shaped because its cross-sectional width, denoted as dimension d 1  in  FIG. 5   e , is greater than its cross-sectional thickness, denoted as dimension d 2 . Helical band coil  145   d  does not have a circular cross-sectional shape as does helical spring  130 , as shown in  FIG. 4   d . It should be noted that helical band coils  145   a ,  145   b ,  145   c  and  145   e  also have cross-sectional dimensions d 1  and d 2  because, as mentioned above, the helical band coils of helical reinforcement member  140  correspond to coils of the single elongate piece of material. In this way, helical reinforcement member  140  includes a single elongate band-shaped piece of material having a width that is greater than its thickness. 
     Dimensions d 1  and d 2  can have many different values. In one embodiment, dimension d 1  has a value between about 0.001 inches to about 0.250 inches, and dimension d 2  has a value between about 0.005 inches to about 0.010 inches. 
     In this embodiment, helical reinforcement member  140  includes a number of arms  147   a ,  147   b ,  147   c  and  147   d , which restrict the ability of helical reinforcement member  140  to stretch and compress in direction  128 , and allow helical reinforcement member  140  to bend in directions  126  and  127 . Arms  147   a - g  are optional. Arm  147   a  is connected between upper portions of helical band coils  145   a  and  145   b  and arm  147   b  is connected between lower portions of helical band coils  145   a  and  145   b . Arms  147   a  and  147   b  are shown connected to upper and lower portions of helical band coil  145   a  in  FIG. 5   d . Arm  147   c  is connected between upper portions of helical band coils  145   c  and  145   d , and arm  147   d  is connected between lower portions of helical band coils  145   c  and  145   d.    
     It should be noted that upper and lower portions of some of the helical coils of helical reinforcement member  140  are not coupled together with arms so that there is a gap therebetween. For example, as shown in  FIG. 5   b , a gap  148   a  extends between the upper portion of reinforcement member  140  between helical band coils  145   b  and  145   c . Further, a gap  148   b  extends between the lower portion of reinforcement member  140  between helical band coils  145   c  and  145   d . Gaps  148   a  and  148   b  allow helical band coils  145   c  and  145   d  to bend in directions  126  and  127 . It should be noted that, in this embodiment, gaps  148   a  and  148   b  extend annularly around reinforcement member channel  141 . Further, gaps  148   a  and  148   b  extend helically around reinforcement member channel  141 . Gaps  148   a  and  148   b  extend helically around reinforcement member channel  141  because band coils  145   c  and  145   d  are helical band coils. In this way, gaps  148   a  and  148   b  are helical gaps. 
     An example of a helical reinforcement member, denoted as helical reinforcement member  140   a , which includes arms extending between upper and lower edges of each helical band coils is shown in  FIG. 5   f . In general, a helical reinforcement member is allowed to bend less as the number of arms extending between the helical band coils increases. A helical reinforcement member is allowed to bend more as the number of arms extending between the helical band coils decreases. Further, a helical reinforcement member is allowed to bend less as the number of gaps extending between the helical band coils increases. A helical reinforcement member is allowed to bend more as the number of gaps extending between the helical band coils decreases. It should be noted that the number of gaps increases and decreases as the number of arms increase and decrease, respectively. 
       FIG. 5   g  is a perspective view of helical reinforcement member  140  in a region  144  of  FIG. 5   a . FIG.  5   h  is a cut-away side view of helical reinforcement member  140  in region  144  taken along a cut-line  5   h - 5   h  of  FIG. 5   g .  FIG. 5   i  is a perspective view of helical reinforcement member  140  in region  144  taken along cut-line  5   h - 5   h  of  FIG. 5   g.    
     Arm  147   a  extends between, and is coupled to, helical band coils  145   a  and  145   b . In this way, helical reinforcement member  140  includes helical band coils coupled together with an arm. Arm  147   a  restricts the ability of helical band coils  145   a  and  145   b  to move towards each other. Hence, arm  147   a  restricts the ability of helical band coils  145   a  and  145   b  to be compressed. Arm  147   a  restricts the ability of helical band coils  145   a  and  145   b  to move away from each other. Hence, arm  147   a  restricts the ability of helical band coils  145   a  and  145   b  to be stretched. In this way, helical reinforcement member  140  includes an arm which restricts the ability of the helical band coils of helical reinforcement member  140  to be stretched and compressed. 
     Helical band coils  145   a  and  145   b  include edges  160  and  161 , respectively, which extend along them. Edges  160  and  161  are spaced apart from each other by a distance d Gap . Distance d Gap  can have many different values. In one embodiment, distance d Gap  has a value between about 0.005 inches to about 0.010 inches. In other embodiments, distance d Gap  has a value between about 0.001 inches to about 0.007 inches. 
     In this embodiment, arm  147   a  extends between edges  160  and  161 . In this way, helical reinforcement member  140  includes an arm which extends between edges of helical band coils. Arm  147   a  restricts the ability of edges  160  and  161  to move towards each other. Hence, arm  147   a  restricts the ability of helical band coils  145   a  and  145   b  to be compressed. Arm  147   a  restricts the ability of edges  160  and  161  to move away from each other. Hence, arm  147   a  restricts the ability of helical band coils  145   a  and  145   b  to be stretched. In this way, helical reinforcement member  140  includes an arm which restricts the ability of edges of helical band coils of helical reinforcement member  140  to move towards and away from each other. 
     In this embodiment, edges  160  and  161  are opposed to each other, and arm  147   a  extends between them. In this way, helical reinforcement member  140  includes an arm which extends between opposed edges of helical band coils. Arm  147   a  restricts the ability of opposed edges  160  and  161  to move towards each other. Hence, arm  147   a  restricts the ability of helical band coils  145   a  and  145   b  to be compressed. Arm  147   a  restricts the ability of opposed edges  160  and  161  to move away from each other. Hence, arm  147   a  restricts the ability of helical band coils  145   a  and  145   b  to be stretched. In this way, helical reinforcement member  140  includes an arm which restricts the ability of opposed edges of helical band coils of helical reinforcement member  140  to be moved towards and away from each other. 
     Helical band coils  145   a  and  145   b  are adjacent to each other because they are adjacent coils. Hence, helical reinforcement member  140  includes an arm connected between adjacent helical band coils. Arm  147   a  restricts the ability of adjacent helical band coils  145   a  and  145   b  to move towards each other. Hence, arm  147   a  restricts the ability of adjacent helical band coils  145   a  and  145   b  to be compressed. Arm  147   a  restricts the ability of adjacent helical band coils  145   a  and  145   b  to move away from each other. Hence, arm  147   a  restricts the ability of adjacent helical band coils  145   a  and  145   b  to be stretched. In this way, helical reinforcement member  140  includes an arm which restricts the ability of adjacent helical band coils of helical reinforcement member  140  to be stretched and compressed. 
     It should be noted that, in this embodiment, arm  147   b  extends between opposed edges  160  and  161  of helical band coils  145   a  and  145   b . Hence, arm  147   b  restricts the ability of edges  160  and  161  to move towards each other. In this way, arm  147   b  restricts the ability of helical band coils  145   a  and  145   b  to be compressed. Arm  147   b  restricts the ability of edges  160  and  161  to move away from each other. In this way, arm  147   b  restricts the ability of helical band coils  145   a  and  145   b  to be stretched. Hence, helical reinforcement member  140  includes more than one arm which restricts the ability of adjacent helical band coils of helical reinforcement member  140  to move towards and away from each other. 
     Arms  147   c  and  147   d  extend between opposed edges of helical band coils  145   c  and  145   d . Hence, arms  147   c  and  147   d  restrict the ability of helical band coils  145   c  and  145   d  to move towards each other. In this way, arms  147   c  and  147   d  restrict the ability of helical band coils  145   c  and  145   d  to be compressed. Arms  147   c  and  147   d  restrict the ability of edges  160  and  161  to move away from each other. In this way, arms  147   b ,  147   c  and  147   d  restrict the ability of helical band coils  145   c  and  145   d  to be stretched. 
     It should be noted that helical reinforcement member  140  stretches in response to one or more of its helical band coils stretching. Hence, arms  147   a ,  147   b ,  147   c  and  147   d  restrict the ability of helical reinforcement member  140  to stretch because they restrict the ability of the helical band coils of helical reinforcement member  140  to stretch. Hence, helical reinforcement member  140  includes an arm which restricts it from stretching. 
     Further, helical reinforcement member  140  compresses in response to one or more of its helical band coils compressing. Hence, arms  147   a ,  147   b ,  147   c  and  147   d  restrict the ability of helical reinforcement member  140  to compress because they restrict the ability of the helical band coils of helical reinforcement member  140  to compress. Hence, helical reinforcement member  140  includes an arm which restricts it from compressing. In this way, helical reinforcement member  140  includes an arm which restricts the ability of the helical band coils of helical reinforcement member  140  to stretch and compress. 
     It should be noted that, in some embodiments, helical reinforcement member  140  includes some helical band coils which are coupled to adjacent helical band coils through one or more arms. For example,  FIG. 5   j  is a perspective view of helical band coil  145   a . In this embodiment, arms  147   a ,  147   e  and  147   f  extend outwardly from edges of helical band coil  145   a , and are coupled to adjacent helical band coils, which are not shown for simplicity. 
       FIG. 5   k  is a perspective view of helical band coil  145   a . In this embodiment, arms  147   a ,  147   e ,  147   f  and  147   g  extend outwardly from edges of helical band coil  145   a , and are coupled to adjacent helical band coils, which are not shown for simplicity. 
     It should be noted that some reinforcement members include non-helical band coils that have the same or a different cross-sectional dimension d 1  than the others coils of the reinforcement member. For example,  FIG. 5   l  is a perspective view of a reinforcement member, denoted as reinforcement member  140   b , which includes helical reinforcement member  140 , as discussed in more detail above. Reinforcement member  140   b  includes a helical band coil  145   f  coupled to helical band coil  145   e , and a non-helical band coil  146  coupled to helical band coil  145   f . Non-helical band coil  146  is non-helical because it is ring shaped and not helically shaped, as in helical band coils  145   a - 145   e . More information regarding reinforcement members which include non-helical band coils is provided below with the discussion of  FIGS. 6   a - 6   i.    
       FIG. 5   m  is a sectional view of non-helical band coil  146  taken along a cut-line  5   m - 5   m  of  FIG. 5   l . In this embodiment, non-helical band coil  146  is band-shaped because its cross-sectional width, denoted as dimension d 3  in  FIG. 5   m , is greater than its cross-sectional thickness, denoted as dimension d 2 . Non-helical band coil  146  has a different cross-sectional dimension than the other coils of reinforcement member  140   b  because it has a cross-sectional dimension d 3  that is greater than cross-sectional dimension d 1  ( FIG. 5   e ) of helical band coils  145   a - 145   f.    
     It should also be noted that some helical reinforcement members include some helical band coils that are restricted from stretching and compressing, and other helical band coils that are not restricted from stretching and compressing. A helical reinforcement member that includes some helical band coils that are restricted from stretching and compressing and other helical band coils that are not restricted from stretching and compressing is useful for many different reasons. For example, in some embodiments of catheter  110 , the helical band coils that are not restricted from stretching and compressing extend through proximal portion  113   a  and the other helical coil bands that are restricted from stretching and compressing extend through distal portion  113   b  ( FIGS. 1 and 2 ). In one particular embodiment, the helical band coils that are not restricted from stretching and compressing extend through nasal passage  101  and the other helical coil bands that are restricted from stretching and compressing extend through gastrointestinal tract  103  ( FIGS. 1 and 2 ). Several examples of helical reinforcement members that include helical band coils that are restricted from stretching and compressing, and other helical band coils that are not restricted from stretching and compressing will be discussed in more detail presently. 
       FIGS. 5   n  and  5   o  are perspective and side views, respectively, of a helical reinforcement member, denoted as helical reinforcement member  140   c , which includes some helical band coils that are restricted from stretching and compressing, and other helical band coils that are not restricted from stretching and compressing. In this embodiment, helical reinforcement member  140   c  includes helical reinforcement member  140 , which is described in more detail above. Further, helical reinforcement member  140   c  includes helical coil bands  145   f ,  145   g  and  145   h  coupled together. In particular, helical coil band  145   f  is coupled to helical coil band  145   e , and helical coil band  145   g  is coupled to helical coil band  145   f . Further, helical coil band  145   h  is coupled to helical coil band  145   g . Reinforcement member channel  141  extends through helical coil bands  145   a - 145   h.    
     It should be noted that helical reinforcement member  140   c  includes a single elongate piece of material that has a helical shape. Hence, the helical coil bands of helical reinforcement member  140   c  correspond to coils of the single elongate piece of material. 
     In this embodiment, helical coil bands  145   a - 145   e  are coupled together with arms  147   a - 147   d , as discussed in more detail above with  FIG. 5   a . Helical coil bands  145   a - 145   e  are coupled together with arms  147   a - 147   d  so they are restricted from stretching and compressing, as discussed in more detail above. However, helical coil bands  145   e - 145   h  are not coupled together with arms so they are not restricted from stretching and compressing. In particular, helical coil bands  145   e - 145   h  are not coupled together with arms so they are not restricted from stretching and compressing in direction  128 . Hence, helical reinforcement member  140   c  includes some helical band coils which are restricted from stretching and compressing, and other helical band coils which are not restricted from stretching and compressing. 
       FIG. 5   p  is a side view of a helical reinforcement member  140   d . In this embodiment, helical reinforcement member  140   d  includes some helical band coils that are restricted from stretching and compressing, and other helical band coils that are not restricted from stretching and compressing. In this embodiment, helical reinforcement member  140   c  includes helical reinforcement member  140 , which is described in more detail above. Further, helical reinforcement member  140   c  includes helical coil bands  145   f ,  145   g  and  145   h  coupled together. In particular, helical coil band  145   f  is coupled to helical coil band  145   e , and helical coil band  145   g  is coupled to helical coil band  145   f . Further, helical coil band  145   h  is coupled to helical coil band  145   g . Reinforcement member channel  141  extends through helical coil bands  145   a - 145   h.    
     It should be noted that helical reinforcement member  140   c  includes a single elongate piece of material that has a helical shape. Hence, the helical coil bands of helical reinforcement member  140   c  correspond to coils of the single elongate piece of material. 
     In this embodiment, helical coil bands  145   a - 145   e  are coupled together with arms  147   a - 147   d , as discussed in more detail above with  FIG. 5   a . Helical coil bands  145   a - 145   e  are coupled together with arms  147   a - 147   d  so they are restricted from stretching and compressing, as discussed in more detail above. However, helical coil bands  145   e - 145   h  are not coupled together with arms so they are not restricted from stretching and compressing. In particular, helical coil bands  145   e - 145   h  are not coupled together with arms so they are not restricted from stretching and compressing in direction  128 . Hence, helical reinforcement member  140   c  includes some helical band coils which are restricted from stretching and compressing, and other helical band coils which are not restricted from stretching and compressing. 
     The gastrointestinal catheter of the present may be made of a thin wall, biocompatible plastic elastomer, such as but not limited to polyurethane, reinforced with a thin helical spring band, such as but not limited to a thin helical spring band of stainless steel. The total wall thickness of, for example, a 6 mm I.D. catheter made in accordance with the present invention can be less than about 1/30 th  its O.D. (one-half to 1 Fr unit) which is only 10-20% the wall thickness of a conventional catheter. 
     The reinforcing spring band may be made in two layers, as a double, overlapping helix, each band of half (or less) the minimum thickness for maintenance of structural stability by a single helical band. 
     The feeding catheter of the present invention may have a single lumen to intermittently deliver or aspirate. The catheter may have a second lumen to permit simultaneous feeding and aspiration of swallowed air and/or undesirable fluids. Additional channels may be present to accommodate inflation of balloons, and/or incorporation of sensors. 
     A fine cloth mesh sleeve, such as, but not limited to polyester, nylon, or a mixture thereof, tightly encases the otherwise exposed distal helical spring band may be utilized. The fine cloth mesh sleeve is generally about 0.002″ thick. This allows free inflow of the gastric and intestinal liquids surrounding that section of the catheter and provides longitudinal stability. The impervious plastic layer will overlay the proximal portion of the spring band, with an approximately one inch of overlap to secure the cloth mesh sleeve in place. The terminal end of the sleeve can be secured to the terminal end of the spring band with adhesive or by other mechanical means. 
     The cloth mesh sleeve may encase the entire length of underlying helical spring band (not shown). An extremely thin layer, about 0.0025″ of heat shrinkable polyester or polyolefin tubing, can be applied to overlay the proximal segment of the catheter, making it impervious to fluid. Heat shrink tubing usually imparts a relative inflexibility to the underlying material. By making this heat shrink tubing ultra-thin, adequate flexibility is achieved. However, this layer may be at risk for “cutting” by the underlying stainless steel spring band. The cloth mesh sleeve between the heat shrink tubing and spring band would protect the former while minimizing the thickness. 
     There is minimal adhesion between the surfaces of the reinforcing spring band, of for example stainless steel and the plastic elastomer, such as polyurethane. The band could shift within the plastic tubing as the catheter flexed, and thereby permit kinking. It has been found that the intrusion of the plastic between the coils by the force of its elastic recoil significantly limits the movement of the coils and reduces kinking. The catheter is assembled so that the elastomer exerts constant tension on the helical spring band. 
     Thin walled tubing having a wall thickness of less than about 0.003″ and whose undistended I.D. is significantly less than the O.D. of the reinforcing spiral band is used. A vacuum process is used to distend the undersized elastomeric tubing, insert the proximal segment of the spring band, and release the vacuum. The recoil of the elastomer will force it into the spaces between the coils, keeping them separated, as well as mechanically holding the coils in place with continuous tension. 
     The proximal segment of the aspiration catheter will have an outer covering of impervious elastomer. The distal segment of the spring band is covered with a “filter sleeve” of very thin, less than about 0.002″, knitted plastic mesh (e.g., polyester). The elastomer will overlap the sleeve and secure it in place. This distal catheter segment will be positioned to lie within the stomach and intestine to aspirate these sites. 
     A small bore feeding tube may be passed co-axially down the aspiration catheter to extend a short distance, less than about 6 cm beyond, but still within the same anatomical segment of intestine, (more distal duodenum or more distal jejunum). The feeding and aspiration sites of the present invention are in the same intestinal segment. The double helix allows for the automatic formation of aspiration orifices. The double helix has multiple trapezoidal openings where the gaps overlap. By simply leave the end segment uncovered by the elastomer, aspiration orifices are formed. 
     The feeding device of the present invention with an internal diameter of about 6 mm will have an O.D. of less than about 20 Fr units, wherein 3 Fr units=1 mm. 
       FIG. 5   q  is a perspective view of helical reinforcement member  140   d  with a cutaway of a portion of the elastomer. The elastomer  201   a, b, c, d, e, f  is covering (dipping down between bands), a fine mesh sleeve  202  (with holes larger than the spacing between coils) is covering the band on the right, with an elastomer short zone of overlap  203 , the coils covered by mesh overlaid with elastomer. 
     The reinforcing spring band may be made in two layers, as a double, overlapping helix, each band of half (or less) the minimum thickness for maintenance of structural stability by a single helical band. The impervious elastomer sheath will cover only the proximal portion of the aspiration catheter. The distal portion of the “double helix,” within the stomach and intestine, will be bare. The right hand spiral over the left hand spiral coils will maintain their positions, much like layers of plywood. However, the spaces between adjacent coils (d gap ) of the overlying layer overlapping the spaces (d gap ) between the underlying layer serve as a large number of aspiration orifices within the stomach and intestine. 
       FIGS. 6   a  and  6   b  are perspective and end views, respectively, of a non-helical reinforcement member  150 . As discussed in more detail below, non-helical reinforcement member  150  is allowed to bend in directions  126  and  127 , and is restricted from stretching and compressing in direction  128  ( FIGS. 6   a  and  6   b ). Non-helical reinforcement member  150  has an outer dimension, which is denoted as dimension d Coil  in  FIG. 6   b . In this embodiment, outer dimension d Coil  corresponds to the outer diameter of non-helical reinforcement member  150 . 
     As shown in  FIG. 6   b , non-helical reinforcement member  150  has reinforcement member channel  141  extending therethrough, and outer reinforcement member surface  142   b  and inner reinforcement member surface  143   b . Inner reinforcement member surface  143   b  faces reinforcement member channel  141  and outer reinforcement member surface  142   b  faces away from reinforcement member channel  141 . It should be noted that outer reinforcement member surface  142   b  and inner reinforcement member surface  143   b  are annular surfaces which extend around reinforcement member channel  141 . Further, outer reinforcement member surface  142   b  and inner reinforcement member surface  143   b  are curved surfaces which curve around reinforcement member channel  141 . Outer reinforcement member surface  142   b  and inner reinforcement member surface  143   b  are non-helical surfaces because they do not extend helically around reinforcement member channel  141 . 
     In this embodiment, non-helical reinforcement member  150  includes a number of non-helical band coils  155   a ,  155   b ,  155   c ,  155   d  and  155   e , wherein helical band coil  155   a  is shown in a perspective view in  FIG. 6   c . Non-helical band coils  155   a ,  155   b ,  155   c ,  155   d  and  155   e  are coupled together so reinforcement member  150  has a non-helical shape. It should be noted that reinforcement member channel  141  extends through non-helical band coils  155   a ,  155   b ,  155   c ,  155   d  and  155   e . It should also be noted that the outer diameter of non-helical band coils  155   a ,  155   b ,  155   c ,  155   d  and  155   e  correspond to dimension d Coil . 
     In this embodiment, non-helical band coils  155   a ,  155   b ,  155   c ,  155   d  and  155   e  each include a single elongate piece of material which has a ring shape. Hence, the band coils of non-helical reinforcement member  150  correspond to separate ring shaped bands of material. 
     In this embodiment, non-helical reinforcement member  150  includes arms  147   a ,  147   b ,  147   c  and  147   d , which restrict the ability of non-helical reinforcement member  150  to stretch and compress in direction  128 , and allow non-helical reinforcement member  150  to bend in directions  126  and  127 . Arm  147   a  is connected between upper portions of non-helical band coils  155   a  and  155   b  and arm  147   b  is connected between lower portions of helical band coils  155   b  and  155   c . Arm  147   c  is connected between upper portions of helical band coils  155   c  and  155   d , and arm  147   d  is connected between lower portions of helical band coils  155   d  and  155   e.    
       FIG. 6   d  is a sectional view of helical reinforcement member  150  taken along a cut-line  6   d - 6   d  of  FIG. 6   a . In particular,  FIG. 6   d  is a sectional view of non-helical band coil  155   e  taken along cut-line  6   d - 6   d  of  FIG. 6   a . In this embodiment, non-helical band coil  155   e  is band-shaped because its cross-sectional width, denoted as dimension d 1  in  FIG. 6   d , is greater than its cross-sectional thickness, denoted as dimension d 2 . Non-helical band coil  155   e  does not have a circular cross-sectional shape as does helical spring  130 , as shown in  FIG. 4   d . It should be noted that non-helical band coils  155   a ,  155   b ,  155   c  and  155   d  also have cross-sectional dimensions d 1  and d 2 . 
     It should also be noted that upper and lower portions of some of the non-helical band coils of helical reinforcement member  140  are not coupled together with arms so that there is a gap therebetween. For example, as shown in  FIG. 6   a , gap  149   a  extends between the lower portion of non-helical band coils  155   a  and  155   b , and gap  149   b  extends between the upper portion of non-helical band coils  155   b  and  155   c . Further, gap  149   c  extends between the lower portion of non-helical band coils  155   c  and  155   d , and gap  149   d  extends between the upper portion of non-helical band coils  155   d  and  155   e . It should be noted that, in this embodiment, gaps  149   a ,  149   b ,  149   c  and  149   d  extend annularly around channel  141 . Further, gaps  149   a ,  149   b ,  149   c  and  149   d  extend non-helically around channel  141 . Gaps  149   a ,  149   b ,  149   c  and  149   d  extend non-helically around channel  141  because band coils  155   a ,  155   b ,  155   c ,  155   d  and  155   e  are non-helical band coils. In this way, gaps  149   a ,  149   b ,  149   c  and  149   d  are non-helical gaps. 
       FIG. 6   e  is a perspective view of non-helical reinforcement member  150  in a region  154  of  FIG. 6   a .  FIG. 6   f  is a cut-away side view of non-helical reinforcement member  150  in region  154  taken along a cut-line  6   f - 6   f  of  FIG. 6   e .  FIG. 6   g  is a perspective view of non-helical reinforcement member  150  in region  154  taken along cut-line  6   f - 6   f  of  FIG. 6   e.    
     Arm  147   a  extends between, and is coupled to, non-helical band coils  155   a  and  155   b . In this way, non-helical reinforcement member  150  includes non-helical band coils coupled together with an arm. Arm  147   a  restricts the ability of non-helical band coils  155   a  and  155   b  to move towards each other. Hence, arm  147   a  restricts the ability of non-helical band coils  155   a  and  155   b  to be compressed. Arm  147   a  restricts the ability of non-helical band coils  155   a  and  155   b  to move away from each other. Hence, arm  147   a  restricts the ability of non-helical band coils  155   a  and  155   b  to be stretched. In this way, non-helical reinforcement member  150  includes an arm which restricts the ability of the non-helical band coils of non-helical reinforcement member  150  to be stretched and compressed. 
     Non-helical band coils  155   a  and  155   b  include edges  160  and  161 , respectively, which extend along them. In this embodiment, arm  147   a  extends between edges  160  and  161 . In this way, non-helical reinforcement member  150  includes an arm which extends between edges of non-helical band coils. Arm  147   a  restricts the ability of edges  160  and  161  to move towards each other. Hence, arm  147   a  restricts the ability of non-helical band coils  155   a  and  155   b  to be compressed. Arm  147   a  restricts the ability of edges  160  and  161  to move away from each other. Hence, arm  147   a  restricts the ability of non-helical band coils  155   a  and  155   b  to be stretched. In this way, non-helical reinforcement member  150  includes an arm which restricts the ability of edges of non-helical band coils of non-helical reinforcement member  150  to move towards and away from each other. 
     In this embodiment, edges  160  and  161  are opposed to each other, and arm  147   a  extends between them. In this way, non-helical reinforcement member  150  includes an arm which extends between opposed edges of non-helical band coils. Arm  147   a  restricts the ability of opposed edges  160  and  161  to move towards each other. Hence, arm  147   a  restricts the ability of non-helical band coils  155   a  and  155   b  to be compressed. Arm  147   a  restricts the ability of opposed edges  160  and  161  to move away from each other. Hence, arm  147   a  restricts the ability of non-helical band coils  155   a  and  155   b  to be stretched. In this way, non-helical reinforcement member  150  includes an arm which restricts the ability of opposed edges of non-helical band coils of non-helical reinforcement member  150  to be moved towards and away from each other. 
     Non-helical band coils  155   a  and  155   b  are adjacent to each other because they are adjacent coils. Hence, non-helical reinforcement member  150  includes an arm connected between adjacent non-helical band coils. Arm  147   a  restricts the ability of adjacent non-helical band coils  155   a  and  155   b  to move towards each other. Hence, arm  147   a  restricts the ability of adjacent non-helical band coils  155   a  and  155   b  to be compressed. Arm  147   a  restricts the ability of adjacent non-helical band coils  155   a  and  155   b  to move away from each other. Hence, arm  147   a  restricts the ability of adjacent non-helical band coils  155   a  and  155   b  to be stretched. In this way, non-helical reinforcement member  150  includes an arm which restricts the ability of adjacent non-helical band coils of non-helical reinforcement member  150  to be stretched and compressed. 
     It should be noted that, in this embodiment, arm  147   b  extends between opposed edges  160  and  161  of non-helical band coils  155   a  and  155   b . Hence, arm  147   b  restricts the ability of edges  160  and  161  to move towards each other. In this way, arm  147   b  restricts the ability of non-helical band coils  155   a  and  155   b  to be compressed. Arm  147   b  restricts the ability of edges  160  and  161  to move away from each other. In this way, arm  147   b  restricts the ability of non-helical band coils  155   a  and  155   b  to be stretched. Hence, non-helical reinforcement member  150  includes more than one arm which restricts the ability of adjacent non-helical band coils of non-helical reinforcement member  150  to move towards and away from each other. 
     Arms  147   c  and  147   d  extend between opposed edges of non-helical band coils  155   c  and  155   d . Hence, arms  147   c  and  147   d  restrict the ability of non-helical band coils  155   c  and  155   d  to move towards each other. In this way, arms  147   c  and  147   d  restrict the ability of non-helical band coils  155   c  and  155   d  to be compressed. Arms  147   c  and  147   d  restrict the ability of edges  160  and  161  to move away from each other. In this way, arms  147   b ,  147   c  and  147   d  restrict the ability of non-helical band coils  155   c  and  155   d  to be stretched. 
     It should be noted that non-helical reinforcement member  150  stretches in response to one or more of its non-helical band coils stretching. Hence, arms  147   a ,  147   b ,  147   c  and  147   d  restrict the ability of non-helical reinforcement member  150  to stretch because they restrict the ability of the non-helical band coils of non-helical reinforcement member  150  to stretch. Hence, non-helical reinforcement member  150  includes an arm which restricts it from stretching. 
     Further, non-helical reinforcement member  150  compresses in response to one or more of its non-helical band coils compressing. Hence, arms  147   a ,  147   b ,  147   c  and  147   d  restrict the ability of non-helical reinforcement member  150  to compress because they restrict the ability of the non-helical band coils of non-helical reinforcement member  150  to compress. Hence, non-helical reinforcement member  150  includes an arm which restricts it from compressing. In this way, non-helical reinforcement member  150  includes an arm which restricts the ability of the non-helical band coils of non-helical reinforcement member  150  to stretch and compress. 
     It should be noted that, in some embodiments, non-helical reinforcement member  150  includes some non-helical band coils which are coupled to adjacent non-helical band coils through one or more arms. For example,  FIG. 6   h  is a perspective view of non-helical band coil  155   a . In this embodiment, arms  147   a ,  147   e  and  147   f  extend outwardly from edges of non-helical band coil  155   a , and are coupled to adjacent non-helical band coils, which are not shown for simplicity. 
       FIG. 6   i  is a perspective view of non-helical band coil  155   a . In this embodiment, arms  147   a ,  147   e ,  147   f  and  147   g  extend outwardly from edges of non-helical band coil  155   a , and are coupled to adjacent non-helical band coils, which are not shown for simplicity. 
     An example of a non-helical reinforcement member, denoted as non-helical reinforcement member  150   a , which includes arms extending between upper and lower edges of each non-helical band coils is shown in  FIG. 6   j . In general, a non-helical reinforcement member is allowed to bend more as the number of gaps extending between the upper and lower edges of the non-helical band coils increases. A non-helical reinforcement member is allowed to bend less as the number of arms extending between the upper and lower edges of the non-helical band coils increases. Further, a non-helical reinforcement member is allowed to bend less as the number of gaps extending between the upper and lower edges of the non-helical band coils decreases. A non-helical reinforcement member is allowed to bend more as the number of arms extending between the upper and lower edges of the non-helical band coils decreases. 
     It should be noted that some reinforcement members include non-helical band coils that have the same or a different cross-sectional dimension d 1  than the other non-helical coils of the non-helical reinforcement member. For example,  FIG. 6   k  is a perspective view of a non-helical reinforcement member, denoted as non-helical reinforcement member  150   b , which includes non-helical band coil  155   a ,  155   b  and  155   c  connected together as shown in  FIG. 6   a . In this embodiment, non-helical reinforcement member  150   b  includes non-helical band coil  146  coupled to helical band coil  155   c  through arm  147   c . Non-helical band coil  146  is non-helical because it is ring shaped and not helical shaped, as in non-helical band coils  155   a - 155   e . More information regarding reinforcement members which include non-helical band coils is provided above with the discussion of  FIGS. 5   a - 5   p . As discussed in more detail above,  FIG. 5   m  is a sectional view of non-helical band coil  146  taken along a cut-line  5   m - 5   m  of  FIG. 5   m.    
       FIGS. 7   a  and  7   b  are perspective and end views, respectively, of a resilient reinforcement member tube  151  with reinforcement member channel  141  extending therethrough. Resilient reinforcement member tube  151  is used to manufacture a helical reinforcement member or non-helical reinforcement member, as will be discussed in more detail below. Resilient reinforcement member tube  151  can include many different types of resilient material, such as materially typically included with a spring. The material of reinforcement member tube  151  is harder than the material of resilient tube  120 . 
     The reinforcement member is manufactured from resilient reinforcement member tube  151  by removing portions of resilient reinforcement member tube  151  to form coils, arms and gaps, which are discussed in more detail above. The portions of resilient reinforcement member tube  151  can be removed in many different ways, such as by using a laser. In one embodiment, the laser is turned on and its beam is directed at outer reinforcement member surface  142  and moved across outer reinforcement member surface  142  to form the gaps of the reinforcement member. The laser is turned off and moved relative to outer reinforcement member surface  142  to form the arms and coils. It should be noted that dimension d Gap  ( FIGS. 5   b ,  5   g ,  6   a  and  6   e ) corresponds to a width of the laser beam. 
       FIG. 7   c  is a perspective view of resilient reinforcement member tube  151  showing helical reinforcement member  140  in phantom. Gaps  149   a  and  149   b , as well as the other gaps of helical reinforcement member  140  are formed by removing portions of resilient reinforcement member tube  151 . Some portions of resilient reinforcement member tube  151  that are not removed form arms  147   a  and  147   c , as well as the other arms of helical reinforcement member  140 . Other portions of resilient reinforcement member tube  151  that are not removed form helical coils  145   a ,  145   b ,  145   c  and  145   d , as well as the other helical coils of helical reinforcement member  140 . As mentioned above, a laser can be used to remove desired portions of resilient reinforcement member tube  151  to form helical reinforcement member  140 . 
       FIG. 7   d  is a perspective view of resilient reinforcement member tube  151  showing non-helical reinforcement member  150  in phantom. Gaps  149   a ,  149   b  and  149   c , as well as the other gaps of non-helical reinforcement member  150  are formed by removing portions of resilient reinforcement member tube  151 . Some portions of resilient reinforcement member tube  151  that are not removed form arms  147   a  and  147   c , as well as the other arms of non-helical reinforcement member  150 . Other portions of resilient reinforcement member tube  151  that are not removed form non-helical coils  155   b ,  155   c  and  155   d , as well as the other non-helical coils of non-helical reinforcement member  150 . As mentioned above, a laser can be used to remove desired portions of resilient reinforcement member tube  151  to form non-helical reinforcement member  150 . 
     It should be noted that the arms of the reinforcement member manufactured from resilient reinforcement member tube  151  have the same curvature of resilient reinforcement member tube  151 . The curvature of resilient reinforcement member tube  151  corresponds to the curvature of outer reinforcement member surface  142  and inner reinforcement member surface  143 . 
     It should also be noted that the coils of the reinforcement member manufactured from resilient reinforcement member tube  151  have the same curvature of resilient reinforcement member tube  151 . The curvature of resilient reinforcement member tube  151  corresponds to the curvature of outer reinforcement member surface  142  and inner reinforcement member surface  143 . 
       FIGS. 8   a  and  8   b  are perspective and end views, respectively, of a vacuum tube system  170 , which is used to manufacture a catheter which includes a resilient tube and reinforcement member.  FIG. 8   c  is a cut-away side view of vacuum tube system  170  taken along a cut-line  8   c - 8   c  of  FIG. 8   a.    
     In this embodiment, vacuum tube system  170  includes a vacuum tube  171  with a vacuum tube channel  173  extending therethrough. Vacuum tube  171  includes a vacuum tube inner surface  174  and vacuum tube outer surface  175 , wherein vacuum tube inner surface  174  faces vacuum tube channel  173  and vacuum tube outer surface  175  faces away from vacuum tube channel  173 . 
     Vacuum tube system  170  includes a vacuum tube nozzle  172  in fluid communication with vacuum tube channel  173  through vacuum tube  171 . Vacuum tube system  170  includes vacuum tube clamps  176  and  177 , which extend around the outer periphery of vacuum tube  171 . 
     Vacuum tube  171  has a length L Vacuum , as indicated in  FIG. 8   c . Length L Vacuum  can have many different values. In one embodiment, length L Vacuum  has a value that is about equal to the length of catheter  110  ( FIG. 2 ). As mentioned above, the length of catheter  110  corresponds to the sum of lengths L 1  and L 2 . In one embodiment, length L Vacuum  is between about thirty inches to about sixty inches. In another embodiment, length L Vacuum  is between about thirty five inches to about forty five inches. 
     Vacuum tube  171  has a dimension d Vacuum , as indicated in  FIG. 8   c . Dimension d Vacuum  corresponds to an inner dimension of vacuum tube channel  173 . The inner dimension of vacuum tube channel  173  corresponds to a diameter of vacuum tube channel  173  because vacuum tube  171  is circular in shape, as shown in  FIG. 8   b.    
     Dimension d Vacuum  can have many different values. In one embodiment, dimension d Vacuum  has a value in a range between about 0.100 inches to about 0.500 inches. In other embodiments, dimension d Vacuum  has a value in a range between about 0.200 inches to about 0.500 inches. 
       FIG. 9   a  is a cut-away side view of vacuum tube system  170  taken along cut-line  8   c - 8   c , wherein resilient tube  120  extends through vacuum tube channel  173 . Resilient tube  120  extends through vacuum tube channel  173  so that outer resilient tube surface  122  faces vacuum tube inner surface  174 . Resilient tube  120  extends through vacuum tube channel  173  so that a vacuum region  179  is formed between resilient tube  120  and vacuum tube  171 . In particular, resilient tube  120  extends through vacuum tube channel  173  so that a vacuum region  179  is formed between outer resilient tube surface  122  and vacuum tube inner surface  174 . It should be noted that vacuum region  179  is in fluid communication with vacuum tube nozzle  172 . Further, it should be noted that vacuum region  179  extends annularly around resilient tube  120 . 
     Opposed ends of resilient tube  120  are folded over opposed openings of vacuum tube  171 . Opposed ends of resilient tube  120  are folded over opposed openings of vacuum tube  171  so that outer resilient tube surface  122  engages vacuum tube outer surface  175 . Opposed ends of resilient tube  120  are folded over opposed openings of vacuum tube  171  so that vacuum region  179  is formed between outer resilient tube surface  122  and vacuum tube inner surface  174 . 
     Clamps  176  and  177  are positioned proximate to the opposed openings of vacuum tube  171 . Clamps  176  and  177  clamp the portions of resilient tube  120  that are folded over opposed openings of vacuum tube  171  so that a seal is formed in response. The seal is formed between resilient tube  120  and vacuum tube  171 , and restricts the flow of the atmosphere of vacuum region  179  therebetween. 
     In  FIG. 9   b , a vacuum system hose  178  is connected to vacuum tube nozzle  172  so that vacuum system hose  178  is in fluid communication with vacuum region  179 . Vacuum system hose  178  is connected to a vacuum system (not shown), which is capable of adjusting the pressure of the atmosphere of vacuum region  179 . The vacuum system is capable of increasing and decreasing the pressure of the atmosphere of vacuum region  179 . 
     Resilient tube  120  moves towards vacuum tube  171  in response to reducing the pressure of the atmosphere of vacuum region  179 . In particular, outer resilient tube surface  122  moves towards vacuum tube inner surface  174  in response to reducing the atmosphere of vacuum region  179 . Outer resilient tube surface  122  moves towards vacuum tube inner surface  174  because force F 1  decreases and force F 2  increases ( FIG. 3   b ) in response to reducing the pressure of the atmosphere of vacuum region  179 . It should be noted that dimension d Tube  ( FIG. 3   b ) increases in response to reducing the atmosphere of vacuum region  179 . It is desirable to increase dimension d Tube  when it is desirable to extend a reinforcement member through resilient tube channel  121 . 
     Further, resilient tube  120  moves away from vacuum tube  171  in response to increasing the atmosphere of vacuum region  179 . In particular, outer resilient tube surface  122  moves away from vacuum tube inner surface  174  in response to increasing the atmosphere of vacuum region  179 . Outer resilient tube surface  122  moves away from vacuum tube inner surface  174  because force F 1  increases and force F 2  decreases ( FIG. 3   b ) in response to increasing the pressure of the atmosphere of vacuum region  179 . It should be noted that dimension d Tube  ( FIG. 3   b ) decreases in response to increasing the atmosphere of vacuum region  179 . It is desirable to decrease dimension d Tube  when it is desirable to stretch resilient tube  120  over a reinforcement member extending through resilient tube channel  121 . 
       FIG. 9   c  is a cut-away side view of vacuum tube system  170  and resilient tube  120 , as shown in  FIG. 9   b . In  FIG. 9   c , reinforcement member  140  extends through resilient tube  120 . In particular, reinforcement member  140  extends through resilient tube channel  121 . As mentioned above, reinforcement member  140  has dimension d Coil , which corresponds to its outer diameter. Dimension d Tube  is increased so that it is greater than dimension d Coil . Dimension d Tubr  is increased so that it is greater than dimension d Coil  so that reinforcement member  140  can extend through resilient tube channel  121 . Dimension d Tube  is increased in response to reducing the pressure of the atmosphere of vacuum region  179 . As mentioned above, force F 1  is decreased and force F 2  is increased in response to increasing the pressure of the atmosphere of vacuum region  179 . 
       FIG. 9   d  is a cut-away side view of vacuum tube system  170 , resilient tube  120  and reinforcement member  140 , as shown in  FIG. 9   c . In  FIG. 9   d , reinforcement member  140  extends through resilient tube  120 , and the pressure of the atmosphere of vacuum region  179  is increased so that resilient tube  120  engages reinforcement member  140 . Dimension d Tube  is decreased so that it is driven to dimension d Coil . Dimension d Tube  is decreased in response to reducing the pressure of the atmosphere of vacuum region  179 . As mentioned above, force F 1  is increased and force F 2  is decreased in response to decreasing the pressure of the atmosphere of vacuum region  179 . 
     The pressure of the atmosphere of vacuum region  179  is increased so that resilient tube  120  engages reinforcement member  140  in response. In particular, the pressure of the atmosphere of vacuum region  179  is increased so that inner resilient tube surface  123  engages helical reinforcement member  140 . Resilient tube  120  engages reinforcement member  140  so that inner resilient tube surface  123  engages the helical band coils, which are discussed in more detail above. In this way, catheter  110   a  is manufactured, wherein catheter  110   a  includes resilient tube  120  and helical reinforcement member  140 . Catheter  110   a  will be discussed in more detail with  FIGS. 10   a ,  10   b  and  10   c.    
     It should be noted that helical reinforcement member  140  of  FIG. 9   c  can be replaced with another reinforcement member, such as helical spring  130  and non-helical reinforcement member  150 . In this way, a catheter  110   b , which includes resilient tube  120  and non-helical reinforcement member  150 , is manufactured. Catheter  110   b  will be discussed in more detail with  FIGS. 11   a ,  11   b  and  11   c.    
       FIGS. 10   a  and  10   b  are perspective and end views, respectively, of catheter  110   a , wherein helical reinforcement member  140  is shown as partially extending through resilient tube  120 .  FIG. 10   c  is a close-up view of catheter  110   a  in a region  117  of  FIG. 10   a.    
     Resilient tube  120  is corrugated in response to engaging helical reinforcement member  140 . In particular, portions of resilient tube  120  proximate to the gaps of helical reinforcement member  140  extend inwardly to form a corrugation. For example, the portion of resilient tube  120  proximate to helical gap  148   a  forms a helical corrugation  152 . It should be noted that corrugation  152  is a helical corrugation because, as discussed in more detail above with  FIGS. 5   a - 5   n , helical reinforcement member  140  includes helical band coils adjacent to helical gap  148   a . In particular, corrugation  152  is a helical corrugation because helical reinforcement member  140  includes helical band coils adjacent to helical gap  148   a.    
     It should be noted that, in some embodiments, resilient tube  120  and helical reinforcement member  140  operate as an aspiration tube. In some of these embodiments, a feeding tube (not shown) extends through resilient tube channel  121  and reinforcement member channel  141  of member  140  so that catheter  110   a  operates as a dual lumen catheter. 
       FIGS. 11   a  and  11   b  are perspective and end views, respectively, of catheter  110   b , wherein non-helical reinforcement member  150  is shown as partially extending through resilient tube  120 .  FIG. 11   c  is a close-up view of catheter  110   b  in a region  118  of  FIG. 11   a.    
     Resilient tube  120  is corrugated in response to engaging non-helical reinforcement member  150 . In particular, portions of resilient tube  120  proximate to the gaps of non-helical reinforcement member  150  extend inwardly to form a corrugation. For example, the portion of resilient tube  120  proximate to non-helical gap  149   b  forms a non-helical corrugation  153 . It should be noted that corrugation  153  is a non-helical corrugation because, as discussed in more detail above with  FIGS. 6   a - 6   k , non-helical reinforcement member  150  includes non-helical band coils adjacent to non-helical gap  149   b . In particular, corrugation  153  is a non-helical corrugation because non-helical reinforcement member  150  includes non-helical band coils adjacent to non-helical gap  149   b.    
     It should be noted that, in some embodiments, resilient tube  120  and non-helical reinforcement member  150  operate as an aspiration tube. In some of these embodiments, a feeding tube (not shown) extends through resilient tube channel  121  and reinforcement member channel  141  of member  150  so that catheter  110   b  operates as a dual lumen catheter. 
     It should also be noted that there are many other embodiments of catheter that can be manufactured, one of which will be discussed in more detail presently. 
       FIG. 12   a  is a side view of a catheter  110   c , which includes a resilient tube  120   a  and a non-helical reinforcement member  150   c .  FIG. 12   b  is a side view of non-helical reinforcement member  150   c  in region  116  of  FIG. 12   a .  FIGS. 12   c  and  12   d  are perspective views of resilient tube  120   a  looking in directions  109   a  and  109   b , respectively, of  FIG. 12   a.    
     As shown in  FIG. 12   a , catheter  110   c  includes proximal portion  113   a  and distal portion  113   b . Proximal portion  113   a  and distal portion  113   b  have lengths L 1  and L 2 , respectively. Lengths L 1  and L 2  can have many different values. For example, in one embodiment, length L 1  is between about eight inches to about fifteen inches, and length L 2  is between about thirty inches to about forty inches. It is desirable for proximal portion  113   a  to be able to extend through nasal passage  101  and esophagus  102  without kinking, such as in region  107  ( FIG. 1 ). Further, it is desirable for distal portion  113   b  to be allowed to bend, but restricted from stretching and compressing. 
     As shown in  FIGS. 12   a  and  12   b , region  116  has a length L 3 , along which non-helical reinforcement member  150   c  extends. Non-helical reinforcement member  150   c  includes non-helical band coils  185 , which extend along a length L 4  of non-helical reinforcement member  150   c . Non-helical reinforcement member  150   c  generally includes one or more non-helical band coils  185  connected together with one or more arms. Non-helical reinforcement member  150   c  includes non-helical band coils  186 , which extend along a length L 5  of non-helical reinforcement member  150   c . Non-helical reinforcement member  150   c  generally includes one or more non-helical band coils  186  connected together with one or more arms. Non-helical reinforcement member  150   c  includes non-helical band coils  187 , which extend along a length L 5  of non-helical reinforcement member  150   c . Non-helical reinforcement member  150   c  generally includes one or more non-helical band coils  187  connected together with one or more arms. The non-helical band coils of non-helical reinforcement member  150   c  are connected together with arms, as discussed in more detail above with  FIGS. 6   a - 6   k.    
     It should also be noted that length L 3  is equal to the sum of lengths L 4 , L 5  and L 6 . Lengths L 3 , L 4 , L 5  and L 6  can have many different values. In one embodiment, length L 3  has a value less than about fifteen inches. In some embodiments, length L 3  has a value between about twelve inches and eight inches. 
     In one embodiment, length L 4  has a value less than about six inches. In some embodiments, length L 4  has a value between about five inches and one inch. 
     In one embodiment, length L 5  has a value less than about ten inches. In some embodiments, length L 5  has a value between about eight inches and three inches. It should be noted that, in some embodiments, length L 5  is larger than length L 4 . It should be noted that, in some embodiments, length L 5  is larger than length L 6 . 
     In one embodiment, length L 6  has a value less than about six inches. In some embodiments, length L 6  has a value between about five inches and one inch. It should be noted that, in some embodiments, lengths L 4  and L 6  have the same values. 
     In this embodiment, resilient tube  120   a  includes aspirating orifices  165  and  166  on the side of tube  120   a  looking in direction  109   a , as indicated in  FIG. 12   a . Aspirating orifices  166  are positioned towards the distal end of resilient tube  120   a  and extend along length L 6 . Aspirating orifices  165  are positioned so they extend along length L 4 . Hence, aspirating orifices  165  and  166  are spaced from each other by about length L 5 . 
     In this embodiment, resilient tube  120   a  includes aspirating orifices  167  and  168  on the side of tube  120   b  looking in direction  109   b , as indicated in  FIG. 12   a . Aspirating orifices  167  are positioned towards the distal end of resilient tube  120   b  and extend along length L 6 . Aspirating orifices  167  are positioned so they extend along length L 4 . Hence, aspirating orifices  167  and  168  are spaced from each other by about length L 5 . 
     It should be noted that the sides of tube  120   b  looking in directions  109   a  and  109   b  are opposed to each other. Hence, in this embodiment, aspirating orifices  165  and  167  are opposed to each other. Further, aspirating orifices  166  and  168  are opposed to each other. In this embodiment, aspirating orifices  165  and  166  are the same size, and are oval in shape. Further, in this embodiment, aspirating orifices  165  and  166  are the same size, and are oval in shape. In this embodiment, aspirating orifices  165  and  167  are larger in size than aspirating orifice  165  and  166 . 
     Aspirating orifices  165 ,  166 ,  167  and  168  can have many different sizes. In one embodiment, the major axis of aspirating orifices  165  and  166  are between about 0.05 inches to about 0.12 inches, and the major axis is between about 0.06 inches and 0.15 inches. It should be noted that aspirating orifices  165  and  166  are circular when the major and minor axes are equal. 
     In one embodiment, the major axis of aspirating orifices  167  and  168  are between about 0.08 inches to about 0.25 inches, and the major axis is between about 0.09 inches and 0.30 inches. It should be noted that aspirating orifices  167  and  168  are circular when the major and minor axes are equal. 
       FIG. 13   a  is a flow diagram of a method  200  of manufacturing a reinforcement member. In this embodiment, method  200  includes a step  201  of removing a first portion of a resilient reinforcement member tube to form first and second band coils. 
     In this embodiment, method  200  includes a step  202  of removing a second portion of the resilient reinforcement member tube to form an arm which extends between the first and second band coils. The arm restricts the ability of the first and second band coils to move towards and away from each other. 
       FIG. 13   b  is a flow diagram of a method  210  of manufacturing a helical reinforcement member. In this embodiment, method  210  includes a step  211  of removing a first portion of a resilient reinforcement member tube to form first and second helical band coils. 
     In this embodiment, method  210  includes a step  212  of removing a second portion of the resilient reinforcement member tube to form an arm which extends between the first and second helical band coils. The arm restricts the ability of the first and second helical band coils to move towards and away from each other. 
       FIG. 13   c  is a flow diagram of a method  220  of manufacturing a non-helical reinforcement member. In this embodiment, method  220  includes a step  221  of removing a first portion of a resilient reinforcement member tube to form first and second non-helical band coils. 
     In this embodiment, method  220  includes a step  222  of removing a second portion of the resilient reinforcement member tube to form an arm which extends between the first and second non-helical band coils. The arm restricts the ability of the first and second non-helical band coils to move towards and away from each other. 
       FIG. 14   a  is a flow diagram of a method  230  of manufacturing a catheter. In this embodiment, method  230  includes a step  231  of sealing a resilient tube to a vacuum tube to form a vacuum region therebetween, wherein the first tube includes a channel. 
     Method  230  includes a step  232  of adjusting the pressure of the atmosphere of the vacuum region to adjust the size of the channel. Step  232  can include decreasing the pressure of the atmosphere of the vacuum region to expand the channel. Step  232  can include increasing the pressure of the atmosphere of the vacuum region to contract the channel. 
     Method  230  includes a step  233  of positioning a reinforcement member through the channel. In some embodiments, the reinforcement member is allowed to bend and is restricted from stretching. In some embodiments, the reinforcement member includes first and second coils coupled together with an arm. 
     In some embodiments, method  230  includes a step of increasing the pressure of the atmosphere of the vacuum region to contract the channel so that the resilient tube is stretched around the reinforcement member. 
       FIG. 14   b  is a flow diagram of a method  240  of manufacturing a catheter. In this embodiment, method  240  includes a step  241  of sealing a resilient tube to a vacuum tube to form a vacuum region therebetween, wherein the first tube includes a channel. In some embodiments, step  241  includes folding opposed ends of the resilient tube over the vacuum tube to form a seal therebetween. In some embodiments, step  241  includes clamping opposed ends of the resilient tube to the vacuum tube to form a seal therebetween. 
     Method  240  includes a step  242  of decreasing the pressure of the atmosphere of the vacuum region to increase the size of the channel. 
     Method  240  includes a step  243  of positioning a reinforcement member through the channel, wherein the reinforcement member is allowed to bend and is restricted from stretching. In some embodiments, the reinforcement member includes first and second coils coupled together with an arm. In some embodiments, the reinforcement member is a helical reinforcement member and, in other embodiments, the reinforcement member is a non-helical reinforcement member. 
     In this embodiment, method  240  includes a step  244  of increasing the pressure of the atmosphere of the vacuum region so that the resilient tube is stretched around the reinforcement member. 
     It should be noted that the steps in the methods disclosed herein can be carried out in many different orders. It should also be noted that the catheters of the methods disclosed herein generally include one or more lumens. Further, in some embodiments, the catheters can be included in a dual lumen device. For example, the catheter can be attached to and carried by an aspiration tube, wherein the aspiration tube can include inner and outer layers of resilient material with a spring positioned between them. The methods disclosed herein can include one or more of the steps disclosed in the methods described in U.S. patent application Ser. No. 11/838,657, which is incorporated by reference as though fully set forth herein. 
     The embodiments of the invention described herein are exemplary and numerous modifications, variations and rearrangements can be readily envisioned to achieve substantially equivalent results, all of which are intended to be embraced within the spirit and scope of the invention.