this invention provides an i - v catheter placement device operable with one hand and having a two - stage needle retraction mechanism using one set of release tabs . the first stage of retraction effectively blunts the needle tip and allows insertion of the full length of the catheter without risk to the patient , while the second stage of retraction fully retracts the needle hub , with its contaminated introducer needle attached , harmlessly into the body of the catheter placement device where it is captured and encapsulated , thus protecting the clinician from an accidental needlestick injury . once encapsulated inside the body of the catheter placement device , there is no risk of accidentally pricking or poking human tissue , thus minimizing the likelihood of transfer of blood borne pathogens which may be carried by fluids contained on the surface of or within such needle . other advantages and features will become apparent from the following description and reference to the figures . fig1 and 2 illustrate the catheter placement device 1 of this invention with the needle 13 and catheter 43 in its normal pre - injection position . fig2 , however , shows the final position of the needle 13 after operation of the retraction cycle so that the needle hub 41 ( with needle 13 attached ) is held in hollow catheter body 17 and rendered harmless after the placement of the catheter 43 has taken place . the i - v catheter placement device 1 has relatively few components . referring to fig1 , i - v catheter placement device 1 has a hollow barrel or body 17 with a nose 3 attached to one end . barrel 17 is closed at the opposite end . a passageway 9 through nose 3 communicates with the interior of the hollow barrel 17 . a proximal end of hollow needle 13 is fixed in a through hole 14 of needle hub shaft 39 , which is in communication with a magnified blood “ flash - back ” verification cavity 53 in needle hub 41 . membrane 31 is positioned in the verification cavity 53 remote from needle 13 to allow airflow through membrane 31 but to prevent flow of blood into hollow barrel 17 as the catheter is inserted into a patient &# 39 ; s vein . needle hub 41 is controlled in the passageway 9 within the nose 3 by needle hub shaft 39 , and is in contact with spring 15 , which is compressed into the passageway 9 ahead of needle hub shaft 39 . the distal end of the needle 13 passes through spring 15 , passageway 9 , and nose boot 25 and protrudes from the nose end of the catheter injection system 1 . covering the exposed shaft of the needle 13 , while leaving the point of the needle 13 exposed , is a thin wall concentric sleeve , or catheter 43 , which is free to slide completely along the distal end of needle 13 . catheter 43 is fixed to nose 3 at catheter head 45 by light friction between catheter head 45 and nose boot 25 which provides a liquid tight seal between the catheter head 45 and nose boot 25 and also makes them easily separable during use . needle hub shaft 39 , into which is fixed the proximal end of needle 13 in a through hole 14 running the length of shaft 39 , is an appendage of needle hub 41 . needle hub 41 has winged beams 33 r and 33 l which are cantilevered from the back of the needle hub 41 in the direction of the needle hub shaft 39 and project at an angle away from needle hub shaft 39 . the geometry of the distal end of winged beams 33 r and 33 l is defined with an angled catch 35 r for coupling the needle hub 41 , with spring 15 in contact therewith , into retainer slot 7 r in the side wall of nose 3 . on the adjacent side of catch 35 r is a release contact point 37 r for operationally releasing needle hub 41 from retainer slot 7 r through the application of force during retraction of the needle 13 into the body 17 during use . in its pre - activated retraction state , spring 15 urges needle hub 14 away from nose 3 . however , needle hub 41 is held by angled catch 35 r on winged beam 33 r in its position in passageway 9 . use of i - v catheter placement device 1 is accomplished by holding the catheter placement device 1 at its symmetrical finger grips 27 in one hand such that orientation message 63 “ use this side up ” is readable by the clinician , with needle 13 pointed away from the clinician . the placement site of the patient is held with the other hand , such that the second hand is behind the needle at all times and is intrinsically protected from possible needlestick by the patient &# 39 ; s body . the tip or point 59 of needle 13 , with the catheter 43 , is just placed into the patient at the desired location . verification of correct location of the catheter 43 is obtained by clinician observation of blood flash - back into magnified transparent verification cavity 53 in needle hub 41 . once proper location is confirmed , release tabs 29 r and 29 l are simultaneously depressed two times a ) effectively to blunt the needle tip , and b ) to retract needle 13 into the body of catheter 17 . as may be seen in fig2 and fig1 , actuation of the catheter placement device 1 retraction cycle occurs when release tabs 29 r and 29 l , just in front of finger grips 27 of the catheter placement device 1 , are simultaneously depressed . when this occurs , force is applied by contact pads 19 r and 19 l on the interior surfaces of release tabs 29 r and 29 l to release contact points 37 r and 37 l on the winged beams 33 r and 33 l of the needle hub 41 . as force is applied , inward movement of catches 35 r and 35 l in their respective retaining slots 7 r and 7 l occurs , and catches 35 r and 35 l , holding the needle hub 41 into its cocked position , are subsequently released in two sequential depressions of release tabs 29 r and 29 l . as catch 35 l releases from retainer slots 7 l , there is nothing to restrain needle hub 41 , and needle hub 41 is triggered , allowing energy stored in spring 15 to be released , projecting needle hub 41 with its embedded needle 13 towards the closed end of barrel 17 . once needle hub 41 is released , it is guided by channels 23 on an interior of the barrel 17 towards the closed end of barrel 17 . needle hub 41 is prevented from escaping from the interior of the barrel 17 by residual force from spring 15 . fig3 through 10 more particularly illustrate the components of i - v catheter placement device 1 . fig3 is an isolated top view of nose 3 showing passageway 9 . retainer slots 7 r and 7 l which lock the needle hub 41 into its operational positions are also shown . longitudinal grooves or channels 5 guide the needle hub 41 in the nose 3 during the retraction cycle , and stop 67 helps capture catch 35 l during the first stage of needle retraction of needle hub 41 . fig4 is proximal end view illustrating nose 3 of this invention and showing the channels 5 and tabs 11 . tabs 11 are used to attached the nose 3 to body 17 . fig5 is an elevational view of the spring 15 . fig6 is a top view of body 17 . release tabs 29 r and 29 l project from symmetrical finger grips 27 , and slots 21 on both the top and bottom sides of the body 17 receive tabs 11 when attaching the nose 3 . contact pads 19 r and 19 l on the interior surfaces of the release tabs 29 r and 29 l cooperate with release catches on the needle hub . also illustrated in this view are channels 23 which guide the needle hub 41 in the body 17 during retraction of needle hub 41 , and the orientation message “ use this side up ,” with two reference lines labeled as “ 1 ” and “ 2 ” to show the positions of the needle hub during both stages of needle retraction . fig7 is a distal end view of body 17 , illustrating release tabs 29 r and 29 l , channels 23 , and contact pads 19 r and 19 l , and air release hole 47 in the proximal end of barrel 17 . fig8 is a side view of needle hub 41 illustrating the space 31 ′ for membrane 31 , transparent verification cavity 53 , winged beams 33 , catches 35 , release contacts 37 and the needle hub shaft 39 projecting between winged beams 33 . fig9 is a proximal end view of needle hub 41 showing magnification surfaces 73 of verification cavity 53 that act as lenses to make the presence of blood in cavity 53 easier to determine . fig1 is a longitudinal sectional view of the catheter 43 and catheter head 45 . fig1 is an isolated sectional view of the membrane 31 . fig1 is an isolated longitudinal sectional view of needle guard 51 illustrating guard - locking ring 49 . fig1 is a proximal end view of boot 25 , and fig1 is a sectional view along line 14 - 14 of boot 25 . assembly in several steps is required to produce the i - v catheter placement device 1 . fig1 through 20 illustrate these steps so as to result in a finished product . with reference to fig1 , the first assembly step is accomplished by inserting needle 13 , with its bevel 57 up , into the needle hub shaft 39 of needle hub 41 . as is illustrated , this gives needle hub 41 a specific orientation , with its elemental parts having the designations shown . the membrane 31 , which may be a hydrophilic medium , is inserted into the hub 41 in the properly sized space 31 ′ provided to receive it . in the next step of the assembly process , boot 25 is inserted onto nose 3 as illustrated in fig1 . orientation of nose 3 is determined by reference to slots 7 r and 7 l because slot 7 l is slightly longer than slot 7 r . the needle 13 and hub 41 subassembly shown in fig1 are next inserted into the proximal end of nose 3 , as shown in fig1 , by first guiding spring 15 onto needle 13 . orientation of the hub 41 and nose 3 is accomplished by insuring that catch 35 r is mated with slot 7 r . once properly oriented , needle 13 is then guided through passageway 9 and projected out of nose 3 , penetrating boot 25 . as winged beams 33 r and 33 l approach nose 3 , they are aligned with channel 5 , flexed inward to create a spring affect along the beam , to fit the beams into channels 5 on either side of nose 3 . with the winged beam 33 r and 33 l guided in channels 5 , the needle hub 41 is forced into the nose 3 as shown in fig1 , until needle catch 35 r pops into slots 7 r . catch 35 r remains in slots 7 r due to spring force of the compressed winged beam 33 r and the angle of catch 35 r . this process locks needle hub 41 into nose 3 . needle catch 35 l floats in slot 7 l . fig1 shows a proximal end view of needle hub 41 fixed into nose 3 . the next step of the assembly process is attachment of body 17 to the sub - assembly of fig1 . as shown in fig1 , body 17 is aligned with the subassembly of fig1 such that bevel 57 on needle 13 and orientation message 63 , “ use this side up ” on the top of body 17 face in the same direction . once orientation is accomplished , body 17 is passed over the proximal end of nose 3 , and attachment to nose 3 is accomplished by aligning and forcing slots 21 on body 17 ( shown in fig6 ) over tabs 11 on the nose 3 ( shown in fig3 and 4 ) until they snap into position . the barrel 17 and nose 3 are mechanically keyed with side 69 l being slightly wider than side 69 r ( shown in fig4 ), so that they will only go together in the correct orientation . as is illustrated in fig2 , assembly of the i - v catheter placement device 1 is completed by placing catheter 43 over needle 13 and sliding catheter head 45 onto boot 25 at nose 3 . the catheter head 45 is held in place by light friction between the catheter head 45 and boot 25 . once the catheter 43 is in place , needle guard 51 is locked onto nose 3 by guard - locking ring 49 , completing the assembly process . as will be apparent to those of ordinary skill in the art , there are sequences of assembly other than those described that can be used to produce the completed assembly as shown in fig2 , producing the same i - v catheter placement device 1 ready for operation . the sequence of operation will now be described with regard to fig2 through 27 . as can be seen in fig2 , use of i - v catheter placement device 1 is accomplished by holding the catheter placement device 1 at its symmetrical finger grips 27 in one hand such that the hand is always behind the needle tip and orientation message 63 , “ use this side up ,” is readable by the clinician , with needle 13 pointed away from the clinician . the placement site of the patient is held with the other hand behind the needle , such that the second hand is protected from possible needlestick injury . the point 59 of needle 13 , with the catheter 43 concentric therewith , is inserted into the patient &# 39 ; s vein 55 at the desired location . verification of correct location of the catheter 43 is obtained by observation of blood “ flash - back ” into magnified , transparent verification cavity 53 at the top of body 17 . once proper location is confirmed , release tabs 29 r and 29 l , located just in front of finger grips 27 , are simultaneously depressed . as release tabs 29 r and 29 l are simultaneously depressed , contact pads 19 r and 19 l move toward their respective needle catches 35 r and 35 l , and an audible “ click ” sound is produced . because of the design geometry , contact pad 19 l moves into slot 7 l , behind catch 35 l , before pad 19 r comes into contact with push point 37 r . continued simultaneously movement of the two release tabs causes catch 35 l to become “ trapped ” in slot 7 l between stop 67 and pad 19 l , before pad 19 r forces catch 35 r out of the back of slot 7 r . as pad 19 r forces catch 35 r out of slot 7 r , needle hub 41 , with needle 13 attached therewith , becomes unrestrained and begins to retract under force from spring 15 into the hollow of body 17 . retraction continues until catch 35 l contacts pad 19 l , and retraction is stopped as shown in fig2 . in this state , push point 37 r is captured in channel 5 within nose 3 , where it can no longer affect retraction of needle hub 41 into body 21 . as is shown in fig2 , exertion of pressure on release tabs 29 r and 29 l is discontinued ( although the device continues to be held by the clinician by such release tabs ) by the clinician and such release tabs are allowed to return to their initial , rest positions , at which time another audible “ click ” sound is produced . as release tab 29 l returns to its rest position , pad 19 l releases catch 35 l . at the moment catch 35 l is released by pad 19 l , positive feedback between the two parts is used , increasing the lateral distance between the two parts , to obtain an unobstructed , smooth release of needle hub 41 . once released , needle hub 41 , with needle 13 attached therewith , again becomes unrestrained , allowing further retraction into the hollow of body 17 under the force of spring 15 . retraction continues until catch 35 l comes into contact with the back of slot 7 l and all movement stops . in this state , the first stage of retraction is completed , needle tip 59 is withdrawn within catheter 43 as shown in fig2 , and needle hub 41 is at the fixed reference line “ 1 ” 61 . full insertion of the catheter 43 may now be completed . with needle tip 59 effectively blunted by catheter 43 , full insertion of the catheter into the patient &# 39 ; s vein 55 , without risk of piercing the backside 71 of vein 55 (“ blowing the vein ”) is accomplished without risk to the patient , as shown in fig2 . with the catheter fully inserted into the patient &# 39 ; s vein 55 as shown in fig2 , second stage retraction is accomplished by simultaneously depressing release tabs 29 r and 29 l a second time , which produces an audible “ click ” sound . when this is done , no further reaction is obtained by release tab 29 r , other than to balance the force required to depress the opposite release tab 29 l , which adds stability for one - handed operation of the device . however , as release tab 29 l moves inward , pad 19 l contacts push point 37 l . with continued force and movement , catch 37 l is dislodged from slot 7 l . when this occurs , needle hub 41 , with needle 13 attached , again becomes unrestrained and is projected along channels 5 and 23 , in nose 3 and body 17 respectively , into hollow 17 by the force of spring 15 as shown in fig2 . needle hub 41 is then held in its retracted position at reference line “ 2 ” 65 by residual force from spring 15 . as needle tip 59 passes through boot 25 , the hole left in elastic boot 25 closes , preventing blood flow from the catheter into the hollow of body 17 . external blood flow from the catheter at nose 3 is prevented by boot 25 being in radial contact with the internal surface of catheter head 45 . with all blood flow restricted , catheter body 17 acts as a “ plug ” in the end of catheter head 45 , until it is removed and an i - v line set is plugged into the catheter . exertion of pressure on release tabs 29 r and 29 l by the clinician is discontinued ( although the device continues to be held by the clinician by such release tabs ), and such release tabs are allowed to return to their initial , rest positions . completion of the catheter placement process is depicted in fig2 and 27 . first , digital pressure 75 is applied at vein 55 , where the catheter is inserted into the body . this stops blood flow from the catheter when catheter body 17 is removed . with blood flow blocked , catheter body 17 is removed and safely set aside for later disposal as shown in fig2 . next , i - v line set 77 is inserted into catheter head 45 . digital pressure 75 is then removed , completing the process . as can be understood by reference to fig2 through 27 , an alternative method of needle retraction can be practiced by depressing release tabs 29 r and 29 l in a sequential fashion . for this method , release tab 29 r is first depressed and then released . when release tab 29 r is depressed , catch 35 r is dislodged from the back of slot 7 r . when this occurs , needle hub 41 , with needle 13 attached therewith , becomes unrestrained , since catch 35 l is only floating in its slot 7 l . retraction continues until catch 35 l is stopped at the back of slot 7 l , as shown in fig2 and 24 , effectively blunting needle point 59 within catheter 43 . needle hub 41 is at reference line “ 1 ” 61 . for the second stage of needle retraction , release tab 29 l is depressed and released , dislodging catch 35 l from the back of slot 7 l . as catch 35 l is dislodged from slot 7 l , needle hub 41 , and the attached needle 13 are projected into hollow body 17 as previously described . completion of the cycle occurs as previously described . a second embodiment of this invention , catheter 101 , is shown in fig3 . catheter placement device 101 has a modified nose , which provides for a ) an alternative flow restriction mechanism after the needle is retracted , and b ) secondary locking of the retracted needle within the body of the catheter . fig2 through 42 depict the second embodiment . fig2 through 36 depict the modified parts for catheter 101 . fig2 , 29 , and 30 illustrate nose 103 modified with through hole 195 transverse to the longitudinal axis of catheter 101 . fig3 is a side view of top plug 196 , fig3 is a side view of shuttle spring 197 , fig3 is a side view of shuttle 198 , and fig3 presents a side view of a bottom plug 199 . fig3 is an end view of nose seal 125 , while fig3 is a sectional view of nose seal 125 along line 36 - 36 . fig3 - 39 depict assembly of catheter 101 . needle hub 141 and needle 113 are assembled into nose 103 in the same manner as catheter 1 . nose seal 125 is inserted onto nose 103 , and results in the subassembly shown in fig3 . with needle hub 141 and needle 113 fixed in nose 103 as shown in fig3 , cylindrical plug 199 is inserted into one end of through hole 195 . in the other end of through hole 195 , cylindrical shuttle 198 with tapers at each end , as illustrated in fig3 , is first inserted , followed by shuttle 198 . the assembly process is completed by compressing shuttle spring 197 and inserting plug 196 into through hole 195 in nose 103 as shown in fig3 and 39 . the assembly process is completed by fixing body 117 to nose 103 as in the case of catheter 1 , producing catheter 101 shown in fig3 . as will be appreciated by reference to fig4 , compressed spring 197 is restrained within nose 103 by retaining plug 196 on one end and shuttle 198 at the opposite end , and applies force to one side of shuttle 198 , as shown in fig3 and 39 . the side of shuttle 198 opposite spring 197 is restrained in one half of through hole 195 by the shaft of needle 113 in passageway 109 of nose 103 as illustrated in fig3 and 40 . utilization of catheter 101 is the same catheter 1 . after the catheter is properly placed into the patient and release tabs 129 have been actuated to project needle 113 into the body 117 of catheter 101 as shown in fig4 , the point 159 of needle 113 passes shuttle 198 . once point 159 of needle 113 passes shuttle 198 , shuttle 198 becomes unrestrained and is projected into passageway 109 of nose 103 by force from shuttle spring 197 , thus blocking passageway 109 as illustrated in fig4 . the final operation is illustrated in fig4 , where the catheter 101 is removed from the catheter head 145 and an i - v line set 177 is inserted into catheter head 145 as described for catheter 1 . the alternate embodiments of this invention provide a novel i - v catheter placement apparatus that is operable by a single hand and that , upon completion of catheter injection , captures and encapsulates the needle and renders it harmless within the hollow of the body of the device . alternative configurations , including one utilizing only one release tab , will become apparent to those skilled in the art from a reading of the foregoing description , which is exemplary in nature . all such modification and variations are embraced within the scope of this invention and the following claims .
an intravenous catheter placement device having a hollow body and a nose on one end of the hollow body . a needle hub fits within the nose and contains a needle embedded therein . a catheter is free to slide along the needle and substantially covers the shaft of the needle . winged beams on the needle hub include catches and release tabs that cooperate with slots in the nose to retain the needle hub in the nose . a magnified transparent verification cavity in the needle hub provides for viewing blood flash in the cavity to verify that the intravenous catheter is inserted into the correct location . an energy storage device in contact with the needle hub releasably retains the needle hub to prevent premature projection of the needle hub into the hollow body . upon insertion of the intravenous catheter and introducer needle into a patient , depressing the release tabs triggers the needle hub and blunts the needle within the catheter and projects the needle hub and embedded needle into the hollow body .