What is this? An oximeter (or sat monitor) can tell you how much oxygen is in the blood. You should be as close to 100 as possible. From our experience, we found that our kids would be admitted to the hospital when their 'sat' was 89 or below. My two youngest kids-daughter Kitty and Son #2- have been hospitalized 12 times with asthma.
How times have changed! We used to think having a sat monitor was a luxury. We would borrow one from a neighbor. She inherited her sat monitor from a neighbor who passed away after suffering all his life from Cystic Fibrosis. Now you can buy one at the local corner drugstore.
That sat monitor was a lifesaver for us (literally.) I could check the kids as they slept, because their oxygen levels always dropped while they were asleep. We were warned about this from a respiratory therapist during one of the times Son #2 was in the hospital. He said, "don't relax when he falls asleep and think 'he's finally stopped coughing and can sleep'." He said people with breathing problems can die in their sleep because their oxygen level just keeps dropping until there's not enough oxygen in their system.
So, I spent many a nights pacing the floor and checking my kid's oxygen level with my sat monitor, once it reached 91, we would head to the hospital. I knew once they were in the ER and fell asleep, their level would continue to drop. That would be captured on their sat monitors at the hospital and then the doctors would admit my son or daughter. The nurses can set the alarms to go off when the oxygen level drops too low, and the respiratory therapists and nurses can take over. That's what they're trained for.
Sat monitors (oximeters) have really dropped in price. The hand held unit we always used still sells for $800, but you can find a finger oximeter for as little as $39 at a nation wide drugstore. They even have sizes just for kids.
If your kids have asthma, and you feel like you are always going to the doctor, emergency room, or hospital, I would suggest buying a sat monitor (oximeter.) Especially if you are just learning about asthma. It has saved my kid's life more than once. Talk to your doctor about purchasing one and see what he thinks. He can tell you how they work and when you should bring your child to the doctor's office or emergency room.
The great thing about technology is that it's always changing, and prices are dropping. So, happy shopping!