Infant Pulmonary Function Test
What is an Infant Lung Function Test?
A lung function test measures the size of your child’s lungs and how easily air moves through the airways. The results of this test will give the doctor details as to how well your child’s lungs are working and help them create a treatment plan.
What to Do Before the Exam
1. Your child needs to have an empty stomach for the test. On the day of the test,
- Infants 0 to 6 months
No milk or solid food for 4 hours before the test.
May have clear liquids up to 3 hours before the test
Nothing by mouth for 3 hours before the test.
- Children 6 months and older
No milk or solid food for 6 hours before the test.
May have clear liquids up to 3 hours before the test.
Nothing by mouth for 3 hours before the test.
2. In order to obtain a good and complete test your child will need to be sleep deprived. The sedation medicine used is given orally. How well this medicine works will depend on how sleep deprived your child is; this is critical in obtaining a good test. We suggest that you keep your child up later than usual the night before the test, then wake your child early in the morning, and do not let your child fall asleep on the way to this appointment.
3. If your child uses a bottle, please bring a bottle and formula with you. We will have your child drink before leaving the clinic. We offer clear liquids first, and then the formula.
4. If your child has a special toy or blanket, please bring it with you.
5. If your child becomes ill (cold, fever, runny nose, vomiting, coughing, diarrhea, etc.) within 1 week before the test, please call our office.
6. If your child routinely takes bronchodilator medicine, this should be withheld for at least 4 hours prior to the test.
The Day of the Test
You and your child should check-in at the Pediatric Special Procedures Clinic located on the first floor of the American Family Children’s Hospital.
Please check in by _____________ on ______________________________.
Your child’s test is scheduled at _______________.
A doctor or nurse will talk with you before the exam. Please ask any questions you may have.
The Test
Your child must be asleep to do this test. We will give your child a sleeping medicine (sedative) to help them sleep through the test. The sedative is very safe, but if you have any questions, you should ask your doctor or the doctor in charge of your child’s care at the time of testing. You can be with your child during the test.
Your child will have a heart monitor and a blood oxygen monitor for the entire test. After a short exam, your child will be given a sedative by mouth. It is common for your child to become quite active after getting the sedative while waiting for the drug to take effect. If you are holding your child, give the child firm support, especially on the head and neck. The sedative takes about 20 – 30 minutes to reach full effect.
After it has taken effect, your child will be placed in the testing crib. Pulmonary Function Technologists and other staff will be with your child at all times until he/she wakes up. Be aware that the testing equipment can be noisy. The actual test takes between 1-2 hours. The amount of time the test will take depends on how well your child can sleep through the test. During the test, a mask attached to the pulmonary function machine will be placed over your child’s nose and mouth. Your child will be able to breathe freely throughout the test. A cloth vest will be placed around your child’s chest. Your child will be given gentle breaths to help fill the lungs. Once the lungs are full the vest will give your child a sudden hug that will help blow the air out as he/she exhales. This test allows the technologist to measure the size of your child’s lungs and to determine how easily air moves through the airways. The pressure used in the vest is less than you feel when your blood pressure is being checked. Your child may be given bronchodilator medicine such as albuterol. The test will then be repeated to see if this medicine helps your child’s breathing. The test results will be given to your doctor. The test results may take a few weeks to review fully. Your child’s results will be compared to other children of the same age.
After the Test
Your child will be watched in the Pediatric Special Procedures Clinic until he/she wakes up and is able to eat and drink. Your child can eat and drink like normal after the test. Continue to firmly support your child (especially the head and neck) since she may not have total control and may be sleepy for up to 4 hours after the test. If she does not seem fully awake within 4 – 6 hours, please call our office. Some sedative medicines remain in the body for longer periods of time, and your child may be sleepy for 4 – 12 hours. They should always be able to be aroused. Please feel free to call if you have questions or concerns.
Phone Numbers
Pediatric Specialty Clinic (608) 263-6420 or Pulmonary Function Lab (608) 263-7000(Monday – Friday, 8:00 am to 4:30 pm).
After hours, nights, weekends, and holidays, this number will give you the paging operator. Ask for the pediatric pulmonology doctor on call. Leave your name and phone number with the area code. The doctor will call you back. If you live out of the area, please call 1-800-323-8942.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 05/23/2012
Copyright © 05/23/2012 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#5931
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