Previous condo: Monoject vs Terumo Syringes
For those of you who use Monoject syringes (and many do), you may or may not have noticed issues such as inaccurate markings. This is not an issue just with Monojects...they all have them. But lately, the problem has been that the needle no longer extends down all the way through the hub into the insulin. I don't know if this is occurring in all lot numbers but Ella/Rusty and I have gotten several different lot numbers with this problem. The result is that the plunger side of the needle ends up in the hub and draws insulin out of the hub
:shock: And it varies....so you never really know how much insulin is going in the cat.
I ordered some Terumo syringes from ADW Terumo syringes, U-100, .3 cc, 31g, 3/8" needle, 1/2 unit markings
The Terumo barrels are much more narrow than the Monojects and trying to figure out how the doses equated from one syringe brand to another, especially considering the hub issue with the MJs, was difficult at best.
Then our own MJ (Donovan) came to the rescue and sent me an adjustable micropipettor. 10 microliters on the micropipettor is equivalent to 1u. This allowed me to determine the exact amount in what was marked as 1u on the MJs. What I found was similar to our MJ's findings....1u as marked on the MJ syringes varied from 14 - 15.2 microliters or 1.4 - 1.52 units :shock: :shock: I tested several MJ syringes and the majority came out as the 1u actually being 1.46u. The Terumos were actually more accurate: 1.5u on the Terumos was actually equivalent to 14.6 microliters or 1.46u...very close. I was then able to measure an equivalent dose between the two syringes (and I ran it many, many times using several syringes of both brands).
There were several Terumo syringes in the box where the zero line matched up perfectly with the needle side of the plunger when the plunger was gently pushed in. I measured how many mm are in 1u and 0.5u on the Terumo. Anyone can use this info if you are going to switch to Terumos and use a caliper to dose because I checked almost 1/3 of the Terumo syringes in the box I had. There are 1.52mm in 1u and .76mm in 0.5u; which is PERFECT!! (.76 x 2 = 1.52). So if you are using the Terumos, and you get five drops to .5u, then divide .76 by 5 to arrive at 0.15 mm/drop. (Likewise, there would be 10 drops in 1u; 1.52mm/10 = 0.15mm/drop).
Yes...it took a lot of time. I worked on it about three hours each on three separate days. I'm sure our MJ could have breezed through it faster but I was so appreciative of the loan of the equipment. I think I have the dose translated as closely as possible....could there be some fine tuning needed?? Absolutely. Nothing, especially the human factor, is without error. And now the guessing is out of my dosing using the calipers and out of how much insulin is in the hub and getting into Gracie on any given shot.
I hope this helps. I'll try to take some pictures and add them to this condo on where I am measuring to/from on the Terumos.
For those of you who use Monoject syringes (and many do), you may or may not have noticed issues such as inaccurate markings. This is not an issue just with Monojects...they all have them. But lately, the problem has been that the needle no longer extends down all the way through the hub into the insulin. I don't know if this is occurring in all lot numbers but Ella/Rusty and I have gotten several different lot numbers with this problem. The result is that the plunger side of the needle ends up in the hub and draws insulin out of the hub
:shock: And it varies....so you never really know how much insulin is going in the cat. I ordered some Terumo syringes from ADW Terumo syringes, U-100, .3 cc, 31g, 3/8" needle, 1/2 unit markings
The Terumo barrels are much more narrow than the Monojects and trying to figure out how the doses equated from one syringe brand to another, especially considering the hub issue with the MJs, was difficult at best.
Then our own MJ (Donovan) came to the rescue and sent me an adjustable micropipettor. 10 microliters on the micropipettor is equivalent to 1u. This allowed me to determine the exact amount in what was marked as 1u on the MJs. What I found was similar to our MJ's findings....1u as marked on the MJ syringes varied from 14 - 15.2 microliters or 1.4 - 1.52 units :shock: :shock: I tested several MJ syringes and the majority came out as the 1u actually being 1.46u. The Terumos were actually more accurate: 1.5u on the Terumos was actually equivalent to 14.6 microliters or 1.46u...very close. I was then able to measure an equivalent dose between the two syringes (and I ran it many, many times using several syringes of both brands).
There were several Terumo syringes in the box where the zero line matched up perfectly with the needle side of the plunger when the plunger was gently pushed in. I measured how many mm are in 1u and 0.5u on the Terumo. Anyone can use this info if you are going to switch to Terumos and use a caliper to dose because I checked almost 1/3 of the Terumo syringes in the box I had. There are 1.52mm in 1u and .76mm in 0.5u; which is PERFECT!! (.76 x 2 = 1.52). So if you are using the Terumos, and you get five drops to .5u, then divide .76 by 5 to arrive at 0.15 mm/drop. (Likewise, there would be 10 drops in 1u; 1.52mm/10 = 0.15mm/drop).
Yes...it took a lot of time. I worked on it about three hours each on three separate days. I'm sure our MJ could have breezed through it faster but I was so appreciative of the loan of the equipment. I think I have the dose translated as closely as possible....could there be some fine tuning needed?? Absolutely. Nothing, especially the human factor, is without error. And now the guessing is out of my dosing using the calipers and out of how much insulin is in the hub and getting into Gracie on any given shot.
I hope this helps. I'll try to take some pictures and add them to this condo on where I am measuring to/from on the Terumos.
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