Scooter's Supplies for Chronic Renal Failure (CRF)

Needle Flow Test Results


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Time to Flow 100 Milliliters of Fluids
Tests conducted by Radford Hunt (see methodology below)

Needle Brand

Diameter
(Gauge)

Length
(inches)

 Style * 

Lot 1
(mins:secs)

Lot 2
(mins:secs)

Average
(mins:secs)

Terumo

18 g

1"

TW

00:55

00:51

00:53

Terumo

19 g

1"

TW

01:17

01:16

01:16

Terumo

20 g

1"

UTW

02:02

01:56

01:59

Terumo

21 g

1"

UTW

02:39

02:37

02:38

Terumo (Sur Vet Label)

21 g

1"

TW

05:59

05:53

05:56

Terumo

22 g

1"

UTW

04:05

04:13

04:09

Terumo 

23 g

1"

UTW

07:16

07:03

07:09

Terumo

25 g

1"

UTW

13:21

13:20

13:20

Monoject

18 g

1"

STD

01:15

01:18

01:17

Monoject

19 g

1"

TW

01:11

01:09

01:09

Monoject

20 g

1"

STD

02:32

02:34

02:33

Monoject

22 g

1"

STD

06:21

06:08

06:15

BD

18 g

1"

STD

01:14

01:10

01:12

BD

20 g

1"

STD

02:28

02:29

02:29

Monoject

22 g

1.5"

STD

07:21

07:13

07:17

Monoject

22 g

.75"

STD

06:04

06:12

06:08

Terumo

26 g

.5"

STD

19:17

-

19:17

Terumo

27 g

.5"

STD

33:10

-

33:10

*  TW = thin wall            UTW = ultra thin wall            STD = standard wall

Methodology:

  • A fixture was made that held the needle end of a 78" long Abbott Labs' 15 drops/per mL Venoset pointing straight down into a graduated cylinder marked at 100 mL.
  • A 1000 mL bag of Abbott's lactated ringer's solution (LRS) was fixed at a height of 57 inches above the needle end of the Venoset as measured from the bottom of the bag where the venoset pierces the seal to the opposite end where the needle is affixed. The line, being longer than the vertical distance, was made to curve once to take up the extra length but at all times remained angled down.
  • Each needle was tested with the beginning fluid level in the Ringers bag set at 500 mL to ensure consistency.  (The Ringers bag was refilled via the injection port each time) 
  • When the bag was refilled I would pinch the venoset as I released the crimp wheel and then I would massage the point on the venoset tubing where the wheel had flattened it.  When the line was fully open, I released it and slid the graduated cylinder under the streaming needle as I started a stop watch.  When 100 mL had flowed into the cylinder, I stopped the watch.  I tested one of each needle (lot1) and then went back and tested a second needle of every type (lot2).  The results of the two flow times were then averaged.  In the table you will see the two individual times under Lot1 and Lot2 and the right hand column is the average of the two. 
  • Note that these are free-flow times and that "in the cat" times will be longer due to back pressure and other variables
  • Tests were repeated using a 10 drops per mL Baxter IV set - flow times were the same.

tests performed and explanation provided by Radford Hunt