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Pulse Oximetry Screening: About Your Child's Test

What is it?

Pulse oximetry (or pulse ox) is one of the routine screening tests that your baby may get. It measures oxygen levels in the blood with a small device wrapped around the hand and foot. It's done to check for serious heart problems (congenital heart defects), and breathing or lung problems. Experts recommend it for most babies.

Why is it done?

The pulse oximetry test can show doctors if your baby might have a breathing or heart problem.

It is a screening test. Screening tests help your doctor look for a certain disease or condition before any symptoms appear.

This test checks for lung or heart problems that lower the oxygen level in your baby's blood. Heart problems are called congenital heart defects. If a baby is born with a lung or heart problem, it's best if doctors know about it right away. If the problem is serious, your child may need to be treated quickly.

How do you prepare for the test?

In general, there's nothing you have to do before this test, unless your doctor tells you to.

How is the test done?

A small, soft sensor will be wrapped around your baby's hand and foot. It's connected to a machine. The machine reads oxygen levels in the blood. Nursery staff will do the test and record the results. You can stay with your baby. If you have questions, ask the staff or doctor.

How long does the test take?

The test takes just a few minutes. If the results show that there might be a problem, the nursery staff may do the test again a little later.

What happens after the test?

  • If test results are in the normal range, then nothing else needs to happen.
  • If test results aren't in the normal range, your baby may be tested again.
  • If the results still show a possible problem, the doctor will talk to you about other tests to check your baby's heart and breathing.

Follow-up care is a key part of your child's treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if your child is having problems. Ask your doctor when you can expect to have your child's test results.

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