What is a Uroflow EMG study and how should the child prepare for it?

The bladder has two jobs. The first job is to store the urine and the second job is to let it out.

With a Uroflow EMG study we can test how well the bladder works… We see how it does the storing and the peeing job. “Uro” refers to urine, “flow” refers to how it is coming out and “EMG” stands for electromyography. This term talks about writing down how much electricity is used in a muscle.

I will try to explain this to your child so you can both understand it:

We need two special sets of muscles to help us do these two jobs of the bladder. By the way, muscles are parts of our body which can help us lift, push, move or hold something. In this case we are talking about the bladder as a group of muscles which have a shape like a water balloon. The second set of muscles are the pelvic floor muscles which act like a door to the bladder.

If the bladder is like a water balloon it can be as small as a grape when it is just about empty or as big as a grapefruit when it is very full. For it to hold the pee inside it has to stretch … and the more it stretches the more you may feel that you have to pee. While the bladder is relaxing, stretching, and filling the door muscles (pelvic floor) tighten up to keep the door closed so hopefully no pee will leak out. And when the bladder is pushing the pee out and its muscles are tightening the door muscles need to relax and stretch “opening the door” so to speak.

During the test we will check how hard these door muscles are working before, during and after you pee. Our special computer will record this and it will also record how fast the pee is coming out and how much pee came out. It will make three graphs that look like this. When we study these graphs, we can understand what may be going on with your bladder and how we can help you make it will work better.

As you may have guessed the test only works when the bladder is full. Many of our patients don’t quite know when the bladder is full or have a hard time with the storing job of the bladder. Hopefully you have prepared by doing the voiding and drinking diary (see other video clip on how to get this information). From that you will know the most your bladder could hold. During the hour before the test you should drink at least twice that much. It usually takes about 1 hour for the body to make the urine after you have been drinking. If you don’t usually drink enough it may take much longer to fill up your bladder. It is not a good idea to hold your urine from the night before even if you are a teenager and hold more than 15 ounces and your appointment is early in the morning. It also helps to know how much a child your age can usually hold. We count the age in years plus one to help us understand how much we can expect a child’s bladder to hold. Therefor if you are 7 years old we hope that you can hold 8 ounces of pee in you without leaking.

When you arrive for the test someone will likely ask you how much you have been drinking and then maybe check your belly with a scan to see how much pee is already inside your bladder. We also sometimes see that a child will try to drink a lot of water too fast. Then we are not surprised when they get nauseated and vomit. Of course, this does not feel good so please start drinking early enough so you can take your time.

Now we should talk about how exactly we can test your bladder.

Whenever any muscle in the body works it uses electricity. This can be measured by small little metal plates, which are part of these special stickers. The door muscles which help you keep the pee inside also wrap around where your poop comes out…And this is where we will gently place the stickers. One sticker goes on either side of the place where poop comes out. The third sticker goes on your hip bone as what we call the “ground”. Without this “ground” we cannot measure electricity. We will be very gentle and respectful when the stickers go on your bottom. And nothing is placed inside of you. For girls it may make placing the stickers a little simpler if you are wearing a dress or skirt the day of the test.

Sometimes children wonder if the stickers will hurt, and they are usually surprised when they do not. It only feels a little strange to have the stickers there for just a short while. Once the stickers are on you the wires get plugged in to this little white box, which can go around your neck like a necklace.

Next your medical assistant may ask you to cough to check if the stickers are reading correctly and you may see a little spike on the screen. Then we will show you the commode in the bathroom where you can pee in private. You can choose to sit or stand. There may be a little stool for your feet if you need it. The commode with a funnel sits over a scale with an empty beaker placed on it. The urine collects in the beaker and the scale measures many times a second what is in the beaker. That’s how we can measure how fast your pee is coming out.

After you are done peeing we need to check very quickly how much pee is left over in your bladder.

Taking the stickers off usually works best if you take a deep breath and then pretend to blow out some birthday candles. While you blow hard your parents or the medical assistant can take off the stickers. Or you can take them off yourself. Since you were drinking so much for the test you may have to pee again several times before you leave our office.

The medical assistant will give the report to your doctor or nurse practitioner and together we can decide how to best help you with your bladder problems.

Thank you very much for cooperating so well and helping us figure out how to help your bladder work better.

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