Patent Publication Number: US-2011071479-A1

Title: Blood Vessel Access Instrument with Vessel Entry Indicator

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a surgical instrument for accessing a blood vessel, and, in particular, relates to a surgical access instrument incorporating a vessel entry indicator to confirm placement of the access instrument within the blood vessel during administration of fluids. 
     2. Background of Related Art 
     Surgical access instruments including intravenous (IV) needles or cannulas are employed during the administration of therapeutic fluids into the blood vessel in conjunction with intravenous (IV) procedures. Such IV procedures may include intermittent or continuous IV therapy for the introduction of specialty pharmaceuticals, blood transfusions, chemotherapy regimens, antibiotic therapy, parenteral nutrition, dehydration treatment or the like. During an intravenous procedure, it is imperative that the IV needle remain within the blood vessel and not become inadvertently dislodged or lose access to the blood vessel. For example, during the IV administration of chemotherapy drugs, if the IV needle is dislodged or removed for any reason from the vein, the drugs may enter the subcutaneous tissue and cause damage to the tissue subjected to the drugs. 
     SUMMARY 
     Accordingly, the present disclosure is directed to a surgical instrument for administering fluids and having a vessel entry indicator to confirm proper placement of the surgical instrument within the vessel. The surgical instrument includes a vessel access member adapted for accessing a blood vessel and having insertion and trailing ends. The access member defines a primary lumen for administering fluids to the blood vessel and a secondary lumen. A pressure detector is in fluid communication with the secondary lumen. The pressure detector is adapted to detect pressure associated with a disposition of the insertion end of the access member in the blood vessel. The access member may define a port adjacent the leading end and in fluid communication with the secondary lumen. In one embodiment, the secondary lumen is independent of the primary lumen. The pressure detector may include a float valve responsive to pressure of blood entering from the blood vessel through the port and into the secondary lumen. In the alternative, the pressure detector includes a pressure gauge. The pressure gauge is adapted to register pressure associated with a presence of blood entering from the blood vessel through the port and into the secondary lumen. 
     In another embodiment, the secondary lumen is in fluid communication with the primary lumen whereby pressure is detected by the pressure detector upon discontinuance of administering fluids through the primary lumen, to thereby permit blood to pass through the primary lumen and enter the secondary lumen. The pressure detector in this embodiment may be a pressure gauge. 
     The primary lumen and the secondary lumen may be coaxially arranged about a reference longitudinal axis defined by the access member. Alternatively, the primary lumen and the secondary lumen are offset with respect to a reference longitudinal axis defined by the access member. The access member may include a housing and an elongate member extending from the housing. 
     A source of therapeutic fluids is adapted to be coupled to the primary lumen. 
     In another embodiment, the surgical instrument for administering fluids includes a vessel access member adapted for accessing a blood vessel and having insertion and trailing ends. The access member defines a primary lumen for administering fluids to the blood vessel and a secondary lumen. The access member has an inlet port adjacent the leading end and in fluid communication with the secondary lumen to permit blood to pass from the blood vessel to enter the secondary lumen, and a return port displaced from the inlet port and in fluid communication with the primary lumen to permit blood to pass from the secondary lumen to the primary lumen for return with the administering fluids to the blood vessel. A fluid flow detector is in fluid communication with the secondary lumen. The flow detector is adapted to detect passage of blood through the secondary lumen when the insertion end of the access member is disposed within the blood vessel. The fluid flow detector may be a flow gauge. The primary lumen and the secondary lumen may be coaxially arranged about a reference longitudinal axis defined by the access member. Alternatively, the primary lumen and the secondary lumen may be offset with respect to a reference longitudinal axis defined by the access member. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the detailed description of the embodiments given below, serve to explain the principles of the disclosure, wherein: 
         FIG. 1  is a side view of a system for administering fluids in accordance with the principles of the present disclosure illustrating the access instrument coupled to a syringe; 
         FIG. 2  is a side cross-sectional view of the access instrument of the system illustrating the housing and the elongate member extending from the housing; 
         FIG. 3  is a cross-sectional view taken along the lines  3 - 3  of  FIG. 1  illustrating the coaxial arrangement of the primary lumen and the secondary lumens within the elongate member; 
         FIG. 4  is a cross-sectional view illustrating an alternate offset arrangement of the primary lumen and the secondary lumen; 
         FIG. 5  is a side cross-sectional view of an alternate embodiment of the access instrument; and 
         FIG. 6  is a side cross-sectional view of another alternate embodiment of the access instrument. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The attached figures illustrate exemplary embodiments of the present disclosure and are referenced to describe the embodiments depicted therein. Hereinafter, the disclosure will be described in detail by explaining the figures wherein like reference numerals represent like parts throughout the several views. 
     The exemplary embodiments of the apparatus disclosed herein are discussed in terms of performing a therapeutic procedure involving administration of fluids into a blood vessel of the subject. Such therapeutic procedures are inclusive of but, not limited to, intermittent or continuous IV procedures for the introduction of specialty pharmaceuticals, blood transfusions, chemotherapy regimens, antibiotic therapy, parenteral nutrition, dehydration treatment or the like. However, it is envisioned that the present disclosure may be employed with many applications and related treatments of diseases and body ailments of a subject. 
     In the following discussion, the term “subject” refers to a human patient or other animal. The term “clinician” refers to a doctor, nurse, or other care provider and may include support personnel. The term “trailing” or “proximal” refers to the portion of the instrument closest to the operator while the term “entry” or “distal” refers to the portion of the instrument remote from the operator. 
     Referring now to  FIG. 1 , the surgical system in accordance with the principles of the present disclosure is illustrated. System  10  is intended to administer fluids in conjunction with a peripheral intravenous (PIV) procedure. System  10  includes IV fluid source  50  and access instrument  100  which administers the fluids of the IV fluid source  50 . The IV fluid source  50  may be in the form of a syringe as shown in  FIG. 1  or may be an external IV fluid source such as an IV bag, drip or the like. The external IV fluid source  50  is couplable to access instrument  100  through conventional coupling means including, e.g., various commercially available tubings, lines and couplings, which are adapted to connect to access instrument  100 . 
     Referring now to  FIG. 2 , in conjunction with  FIG. 1 , access instrument  100  will be discussed. Access instrument  100  is an access member such as a needle, cannula or catheter adapted to access a blood vessel of the subject, particularly, in connection with peripheral IV procedures where the arm or hands are accessed to deliver IV fluids. Access instrument  100  also may be adapted to access a vein in the leg or foot or, in the case of an infant, the scalp. Access instrument  100  includes housing  102  and elongate member  104  connected to the housing  102  and extending therefrom. Housing  102  is adapted to be grasped by the clinician and may be formed of any suitable metal or polymeric material. Housing  102  may be clear or opaque Housing  102  includes main body  106  and detector leg  108  which extends from the main body  106  in oblique relation to the longitudinal axis “k” of the housing  102 . Main body  106  defines proximal or trailing end  110  which is couplable to IV fluid source  50  through various conventional coupling means. In  FIG. 2 , IV fluid source  50  is represented schematically and may be an IV bag, drip or the like. Exemplative coupling means for coupling main body  106  to external IV source  50  include luer connectors, bayonet couplings or the like. In  FIG. 2 , bayonet lugs  112  are shown. As appreciated, the coupling means on the IV line connected to IV fluid source  50  would incorporate corresponding structure to cooperate with the coupling means of main body  106  such as a bayonet female receptor with matching slots for the male bayonet lugs  112 . In the situation where fluid source  50  is a syringe ( FIG. 1 ), leading end  52  of the syringe  50  may penetrate or pass through internal seal  114  within trailing end  110  of main body  106  to be releasably secured therein. Internal seal  114  is adapted to form a substantial fluid tight seal about syringe leading end  52  and may be a septum seal or zero closure seal fabricated from a suitable elastomeric material. 
     Elongate member  104  is preferably formed of a suitable biocompatible material such as stainless steel or other polymeric materials. Elongate member  104  may be clear or opaque. The diameter of elongate member  104  may vary, but, typically ranges from a 12-gauge to a 26 gauge size, e.g., cannula. Elongate member  104  defines leading end  116  which may be adapted to penetrate, incise or pass through tissue to access the vein. 
     With reference to  FIGS. 1-3 , access instrument  100  defines primary lumen  118  which extends from trailing end  110  of housing  102  through leading end  116  of elongate member  104 . Primary lumen  118  is in fluid communication with IV fluid source  50  to deliver or administer the IV fluids to the subject&#39;s vein. Access instrument  100  further defines secondary lumen  120  which extends through inflow ports  122  adjacent entry end  116  of elongate member  104  through the elongate member  104  and detector leg  108 . Secondary lumen  120  is intended to permit blood to flow from the vein into elongate member  104  and detector leg  108  for reasons to be hereinbelow discussed. Inflow ports  122  may be in diametrical opposed relation and formed in the wall of elongate member  104 . Alternatively, inflow port  122  may be an axial port having an annular configuration. Primary and secondary lumens may be concentrically or coaxially arranged about the longitudinal axis as shown in  FIG. 3 . In the alternative, primary and secondary lumens  118 ,  120  may be offset with respect to each other as depicted in  FIG. 4 . 
     Referring now to  FIG. 2 , access instrument  100  further includes pressure detector  124  mounted to detector leg  108  of housing  102  for sensing the pressure within secondary lumen  120 . The pressure is associated with the presence of blood when entry end  116  of elongate member  104  is disposed within vein. Pressure detector  124 , in one embodiment, includes float valve  126  which is mounted within valve housing  128 . Float valve  126  is adapted to reciprocate within housing, in the direction of directional arrows “m”, responsive to the presence or lack of presence of blood within secondary lumen  120 . Float valve  126  may be any conventional float valve suitable for this intended purpose including [Inventor, please provide examples]. In one embodiment, float valve  126  is adapted to reciprocate due to the increased air pressure within secondary lumen due to the presence of blood. In an alternate embodiment, float valve  126  incorporates a floating ball  130  which floats relative to the blood when the blood communicates through the secondary lumen  120  and within valve housing  128 . Various other detectors are envisioned including gauges, transducers, fiber optic sensors, mechanical spring sensors, piezoresistive sensors or transducers, and sensors based upon changes in measured capacitance. 
     In use, entry end  116  of elongate member  104  is advanced through tissue to access the desired vein. When entry end  116  is positioned in the vein, blood enters through inflow port  122  to pass within secondary lumen  120 . The presence of blood within secondary lumen  120  is detected by float valve  126  which moves in a proximal direction within valve housing  128 . Movement of float valve  126  in the proximal direction is confirmed by the clinician who may view the float valve  126  through a transparent portion of valve housing  128 . Access instrument  100  may then be connected to the fluid source  50  to permit administration of the fluids and commencement of therapy. Throughout the fluid administrating process, the clinician will monitor float valve  126  and determine if the float valve  126  is activated and/or oscillating (corresponding to the rhythm of the pulse) which is indicative of the access instrument  100  being lodged appropriately within the vein. 
       FIG. 5  illustrates an alternate embodiment of the present disclosure. In accordance with this embodiment, access instrument  200  includes primary lumen  202  extending the length of elongate member  204  and the length of housing  206 . Access instrument  200  further includes offset detector leg  208  which is arranged in oblique relation to the longitudinal axis of access instrument. Offset leg  208  defines secondary lumen  210  which is in fluid communication with primary lumen  202 . Offset leg  208  further includes pressure gauge  212  mounted thereto. Any suitable commercially available pressure gauge may be employed. Pressure gauge  212  is adapted to monitor pressure within secondary lumen  210  due to the presence of blood within the secondary lumen  210 . In one embodiment, offset leg  208  includes a male/female luer connector which connects to a corresponding connector of pressure gauge  212 . In  FIG. 5 , IV connector  54  for connecting external IV fluid source  50  to housing  206  is shown. 
     In use, primary lumen  202  is flushed with a saline. Access instrument  200  is then advanced within the tissue and into the vein with a blood flashback flowing through primary and/or secondary lumens  202 ,  210  confirming that entry end  214  is within the vein. The presence of blood within primary and/or secondary lumens  202 ,  210  may be visualized through a transparent region of elongate member  204  or housing  206 . Housing  206  of access instrument  200  is connected to IV fluid connector  54  or a syringe, and administration of fluids through primary lumen  202  is commenced. When it is desired to check that entry end  214  of elongate member  204  is properly positioned within the vein, the infusion or administration of fluids is interrupted. The blood is permitted to communicate through primary lumen  202  and into secondary lumen  210 . Pressure associated with the presence of blood is registered by pressure gauge  212  either through a constant pressure or through an oscillation of pressure (corresponding to the subject&#39;s pulse). If no pressure is recorded by pressure gauge  212 , it can be determined that access instrument  200  is not within the vein, thus, prompting the clinician to reposition entry end  214  of the access instrument  200  within the vein. 
       FIG. 6  illustrates another alternate embodiment of the present disclosure. Access instrument  300  includes housing  302  and elongate member  304  extending from the housing  302 . Access instrument  300  includes primary lumen  306  extending the length of the access instrument  300  for administration of fluids from a fluid source. Elongate member  304  further includes secondary lumen  308  within the outer wall of elongate member  304  and outlet port  310  in fluid communication with the secondary lumen  308 . Access instrument  300  further includes flow gauge  312  mounted to elongate member  304 . Flow gauge  312  may be any suitable conventional gauge adapted to detect the presence of fluid or detect the flow of fluid. Flow gauge  312  is in fluid communication with primary lumen through inflow tube  314  and outflow tube  316 . Flow gauge  312  may be mounted to housing  302 . 
     In use, entry end  310  of access instrument  300  is positioned within the vein. Administration of fluids from the fluid source (not shown) through primary lumen  306  is commenced. Concurrently with the administration of fluids, blood enters secondary lumen  308  through entry port  310  and communicates through inflow tube  314  and travels across flow gauge  312 . This flow of blood is registered by flow gauge  312 . The blood thereafter communicates through outflow tube  316  where it is released into primary lumen  300  for return, along with the IV fluids, into the vein of the subject. If no fluid flow is registered by flow gauge  312 , the clinician will determine that access instrument  300  is not properly positioned within the vein, thus, prompting the clinician to act accordingly to reposition the access instrument  300 . 
     Although the foregoing disclosure has been described in some detail by way of illustration and example, for purposes of clarity or understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims.