Pulmonary Diagnostics Lab

Scheduling a Pulmonary Function Test (PFT)

We welcome referrals for PFTs for children ages 5 through 21. Referrals are required. Patients do not need to be seen by our Pulmonary Clinic first.

To refer a patient:

  • Fax a New Appointment Request Form (PDF), (DOC) to 206-987-3121 or use EpicCare Link.
  • Clearly state you are ordering a pulmonary function test (PFT) and which test(s) you are ordering. A “full PFT” order is generally understood as spirometry, plethysmography and diffusing capacity.   
  • Have your patient’s parent or caregiver call 206-987-2174, option 1 to schedule their PFT appointment.

If you do not specify which tests you want, we will fax you to request more information, which may delay your patient’s appointment.

Types of tests

  • Spirometry: Measures forced expiratory volumes and flows to determine if vital capacity is normal and whether airway obstruction is present. Appropriate for patients >5 years old.
  • Spirometry Pre- and Post-Bronchodilator: Measures forced expiratory volumes and flows to determine if vital capacity is normal and whether airway obstruction is present and whether obstruction is improved following albuterol. Appropriate for patients >5 years old. Best test for asthma.
  • Spirometry Bronchodilator protocol: Measures forced expiratory volumes and flows to determine if vital capacity is normal and whether airway obstruction is present. Depending on this first step and concern for airflow obstruction, the respiratory therapist performing the test might decide to provide the patient with a bronchodilator and repeat the test to look for potential response. This test is different from “Spirometry Pre- and Post- Bronchodilator” in which the patient gets a bronchodilator regardless of initial results. Appropriate for patients >5 years old.
  • Fraction of exhaled nitric oxide measurement (FENO): Measures exhaled nitric oxide. Elevated/high FENO indicates significant eosinophilic/allergic inflammation, where eosinophilic inflammation is NOT well controlled. This test may indicate that a patient needs medication adjustment or improved compliance, and also in new patients can help identify a specific phenotype of asthma (TH2 high/eosinophilic) that is particularly responsive to certain medications (e.g., inhaled steroids, monoclonal antibody blockade of IL-5 or IL-13). Appropriate for patients >5 years old.
  • Plethysmography (total lung volumes): Measures complete fractional lung volumes, including residual volume (trapped gas following a complete exhalation). Appropriate for patients >8 years old. Best test for scoliosis, pectus and rheumatological or immune patient; former cancer; or bone marrow transplant patients.
  • Diffusing capacity: Measures oxygen transport from lungs to blood. Appropriate for patients >8 years old. Best for rheumatological disease, former cancer or bone marrow transplant patients; congenital heart disease; sickle cell disease; and dyspnea.
  • Hypoxic challenge (high altitude test): The “airplane test” measures a patient’s ability to maintain normal oxygen saturations when breathing a reduced O2 concentration (to mimic breathing at a low partial pressure of oxygen such as on an airplane or at altitude). Best for ex-preemies or any child on O2. Children must be developmentally/behaviorally able to tolerate having a mask with good seal on their face for 15 minutes continuously (e.g., usually not successful for children under age 2 to 3 years old).
  • Six Minute Walk Test (6MWT): Measures physical function and therapeutic response in patients with conditions such as chronic lung disease, restrictive lung disease, interstitial lung disease and pulmonary hypertension. The patient walks on a certain measured path in the clinic while the total distance walked and vital signs, including oxygen saturation and heart rate, are recorded and evaluated. Appropriate for patients >5 years old.
  • Exercise bronchoprovocation testing: This test identifies asthma in patients with recurrent and episodic dyspnea who have normal or near normal spirometry at baseline. A trial of therapy for asthma is another option, but bronchoprovocation testing might be preferred to identify a precise diagnosis of asthma. The test includes baseline spirometry testing followed by exercise on a stationary bike to achieve a goal heart rate and workload. After the biking exercise is completed, multiple and serial spirometry tests are performed and compared at certain time points. Appropriate for patients >10 years old.

All types of PFTs are patient dependent. If a patient is unable to understand and/or follow instructions, then the test results may be invalid. Our schedulers will ask your patient if they need an interpreter at the time their appointment is scheduled.

Providers are welcome to contact us with questions:

  • Call 206-987-2174. If calling to schedule a PFT, press option 1.
  • Speak with a pulmonary specialist by calling the Provider-to-Provider Line: 206-987-7777.

What Patients Can Expect During a Pulmonary Function Test

  • Depending on the type and number of tests ordered, appointments generally run 30 to 60 minutes. Any patient having testing on top of the “full PFT” order can expect their appointment to last 90 minutes. A full PFT order is generally understood as spirometry, plethysmography and diffusing capacity.   
  • For children undergoing the hypoxic challenge, parents may want to bring a tablet device or smart phone to help their child tolerate the required mask during the test.
  • Because test results are dependent on patient cooperation and understanding, we coach the child in order to obtain the best results possible and will at times partner with parents to help achieve this. None of our pulmonary tests should induce pain, but patients may experience mild discomfort. If at any time patients feel pain or dizziness, continued testing will be re-evaluated.
  • If a test result is not obtained, parents should not feel as if the visit was fruitless. PFTs require coordinated, sustained breathing patterns that are patient dependent. Even older children may not be able to complete all testing. The important part is to know the patient has gained experience in testing procedures and to keep the experience as positive as possible should future testing be needed.
  • Some families would like to take videos/pictures of equipment and staff during actual testing. We ask that they refrain from this practice. If they would like a video/picture memento from their visit, we request they ask staff first.

Location and Hours

The Pulmonary Diagnostics Lab is located on Ocean 6 in the hospital. It is the only location where "full PFTs" (spirometry, plethysmography and diffusing capacity) are performed. Hypoxic challenges are also performed here.


  • Pulmonary Diagnostics Lab: Weekdays except for Wednesdays, from 8 a.m. to 5:15 p.m.

Some PFTs are performed in some other locations at the hospital (check in on Ocean 8) and our regional clinics:

  • Other hospital clinic areas: Less complex PFTs, such as spirometry and FENO, are done in a number of hospital clinics (e.g., Cystic Fibrosis Clinic, Chest Clinic, Neuromuscular)
  • Bellevue Clinic: Monday and Wednesday. Spirometry and FENO only.
  • North Clinic in Everett: Monday only. Spirometry and FENO only.
  • South Clinic in Federal Way: Tuesday and Wednesday. Spirometry and FENO only.

Days are subject to change. We do not offer PFTs on weekends and holidays.

Laboratory Leadership

Demet Toprak, MD, medical director, Pulmonary Diagnostic Laboratory

Jean Paul (Gino) Villavicencio, RRT, respiratory care manager