ATS Pulmonary Function Laboratory Manual

chapter  14

3.7. Environmental factors: room temperature, relative humidity, and barometric pressure 3.8. Additional provocations, if applicable

• Dry air • Cold air • Delivery method (e.g. reservoir bag, and demand valve)

3.9. Clinical signs and symptoms (e.g., wheezing and cough) 3.10. Bronchodilator(s) or other medication(s) administered after exercise, if applicable. Spirometry data from post-bronchodilator stage should be reported.

Procedure Notes 1.

Several factors may influence the test results. 1.1. Repeatability of the PF tests 1.1.1.

If the patient cannot perform repeatable maneuvers, the test is invalid. 1.2. Any exercise preceding the test can cause a refractory period to EIB up to several hours (48, 63). 1.3. The temperature and RH of the inhaled gas can affect the level of response (6, 36, 48, 54, 55). 1.4. The addition of dry air from a compressed gas cylinder may cause a greater response in some indi- viduals (48, 63, 78). 1.5. The addition of cold air (compared to dry air) may cause a greater response in some individuals (19). 1.6. Medications (if not withheld) can affect the test outcome. 1.7. Exercise device selection and usage 1.7.1. Patient performance, coordination, physical limitation with a particular exercise device can affect results. These include: • Inability to walk on treadmill • Weight support on handrails • Inability to coordinate pedaling effort • Orthopedic constrains 1.8. The use of arm ergometry for this test is not recommended because the obtained level of ventilation is usually not high enough. 1.9. Interpretation: a decrease in FEV 1 from baseline of at least 10% is suggestive of EIB (79, 80). How- ever, the specificity is higher with a decrease of ≥ 15% from baseline. 1.10. When the purpose of this test is to evaluate pharmacotherapy (i.e., which drug[s] and what dose will block or attenuate the response), the drug(s) being evaluated should be administered long enough before exercise to ensure they have taken effect. PF tests can be measured before and after the admin- istration of the drug(s), although the essential measurement is after administration and just prior to exercise (81). 1.11. The use of a facemask to deliver dry and/or cold air is not recommended because of the warming and humidification effect. 1.12. Patient Safety: The most common problem encountered in exercising a patient with asthma is severe bronchoconstriction that can usually be treated rapidly and successfully by administering nebulized bronchodilator with O 2 . The approach to monitoring will vary depending on the setting and the risk of the patient. A hospital setting may be more appropriate for higher risk patients since a resuscitation team may be readily available. In contrast, a young relatively healthy patient can be tested in a labora- tory with minimal monitoring, an experienced technologist present and a physician in the immediate area. In a setting with less support and a higher risk patient, more intense monitoring by individuals with the skills to appropriately diagnose and treat adverse events would be necessary (52).

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