The two most common reasons for a meter error: not enough blood and the meter times out before you get blood onto the strip.
Are you warming your cat's ear before poking? If not, that will really help. Most people use what is called a "rice sock": a small sock filled with a spoonful or two of uncooked rice or dried beans, knotted close, and heated in the microwave until just warm but not so warm that it will burn your hand or cat's ear. Try 10 seconds in the microwave and adjust as needed. A baby sized sock is all you need but use whatever cotton sock you have. Wrap the warm sock around the edge of the cat's ear and hold in place for a minute if you can. Then hold the sock inside the ear to use as a firm surface to poke against and also keep your fingers safe. Press the lancet device firmly against the edge of the ear and poke. You are aiming for the space between the edge and the vein. If you hit the vein, no big deal. Still no blood? Adjust the depth setting of the device. Still no blood even on the highest setting? The lancet might be too thin. 27 gauge is an ideal size to use. If your lancet device only uses thin lancets, you'll need to buy a different device that uses larger gauze lancets. Or, maybe you need to adjust the placement of the device on the ear. Move the device a little further so the hole where the lancet pokes out of is hitting the ear and not empty air.
If you do get blood but only a pin drop size, try gently pushing on either side of the drop to help it bead up more. You can also try warming the ear for longer and poking in a different spot.
If the meter is timing out, the easy fix is to put the test strip just far enough into the meter so that it holds in place but doesn't turn the meter on. Set aside while you warm the cat's ear. When you are ready to poke, push the test strip all the way into the meter to turn it on. In the few seconds it takes for the meter to turn on and be ready for a blood drop, poke the ear with the lancet device to get blood. Once you get a nice drop of blood (too much is better than too little IMO), apply the drop to the test strip in the ready and waiting meter. If you don't get the blood on because you're poking and not getting blood, just turn the meter off and pull the test strip out just enough so it holds in place. Alternative is to get the blood first and then push the test strip into the meter, wait for the meter to be ready and hope you don't lose the blood because your cat decides to shake his head. It's entirely doable to push the test strip into the meter with one hand while the other hand is holding the ear. Try practicing this. I use my knee as a sort of brace to hold the meter steady while my free hand pushes the test strip in.
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