ATS Pulmonary Function Laboratory Manual

ATS Pulmonary Function Laboratory Management & Procedure Manual | 3rd Edition

Post-test Procedure

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Step Action 4.

If EIB is documented by PF tests: • Administer bronchodilator(s) as needed. • Typically 0.5 ml of albuterol in 1 ml of normal saline is administered by small-volume nebulizer, or two inhalations of albuterol from a metered dose inhaler can be used. • Wait 10 minutes and re-measure PF tests after the bronchodilator to ensure the patient’s FEV 1 is at least 90% of baseline before the patient leaves the laboratory.

Calculations 1. For each interval of spirometric measurements performed after exercise, the highest repeatable FEV 1 should be reported (52). The severity of the response is assessed by taking the interval with the lowest FEV 1 observed after exercise (i.e., interval with the greatest drop), subtracting it from the pre-exercise value, and expressing it as a percentage of the pre-exercise level (4, 36, 48). This is applicable whether using PEFR, FEV 1 , or Raw. % change = pre exercise − post exercise pre exercise × 100 2. Some laboratories measure FEV 1 or PEFR during exercise, especially if airflow obstruction is present at rest. A lability index can then be derived by taking the highest value recorded during exercise, subtracting the lowest reproducible value observed after exercise, and expressing it as a percentage of the pre-exercise level (4, 37). Lability % = highest during exercise − lowest post exercise pre exercise × 100 Reporting of Test Results 1. The units that apply to the measurement of the PF tests are: 1.1. FVC is expressed in L (BTPS) 1.2. FEV 1 is expressed in L (BTPS) 1.3. PEFR is expressed in L/s (BTPS) 1.4. Raw is recorded in cm H 2 O/L/sec 2. The fewest values that constitute an adequate report are the pre-exercise value, the lowest repeatable post- exercise value, and the percent change. 3. Other variables that need to be recorded are: 3.1. Type of exercise device 3.2. Sustained work rate and ventilation, if available 3.3. Total exercise time 3.4. Max HR and length of time at target HR 3.5. Interpretation of the ECG 3.6. O 2 saturation via pulse oximetry, if measured

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