ATS Pulmonary Function Laboratory Manual

chapter  14

Test Procedure for Exercise Challenge Test

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Step Action 10.

Exercise Protocol: • General consensus is that the overall exercise time be 6 to 10 minutes (1, 2, 4–6, 36, 48, 53, 54, 64, 65, 69) • If the target workload is overestimated, the work rate can be reduced during the test to maintain the exercise response in the desired range. • Two methods of achieving the desired exercise level are (5, 64): � Rapid increase in the work rate over the first 1 to 2 minutes to the pre-determined work rate, then continue for 6 to 8 minutes. � In adults it is recommended for safety reasons that the high-work plateau be approached in three steps to allow for careful observations of the cardiopulmonary response (64).

× 2 minutes warm-up at a low intensity × 2 minutes at a moderate work rate × 5 to 8 minutes at the target work rate

11.

Start exercise using selected protocol • Obtain ECG, blood pressure, subjective measurements (i.e., RPE, asthma symptoms) at rest, during and immediately after exercise.

• Blood pressure is often difficult to measure accurately during exercise (75). • Auscultation of the chest can be performed before, during and after exercise (5). 12. Exercise to predetermined end-point or early termination criteria • See sections Exercise Intensity for target • See Table 14.4

Post-test Procedure

Step Action 1.

Post-exercise phase: • There should be a brief cool-down phase at a reduced work rate for 1 to 2 minutes. • An ECG should be recorded every minute until discontinuation of test. Monitoring of physiologic vari- ables should continue until abnormal ECG or blood pressure results are resolved (46). 2 Post-exercise PF tests: • Performed serially for approximately 30 minutes (5, 6, 48, 63–65). • Many laboratories conduct the first PF test immediately after exercise, and then 3, 6, 10, 15, and 30 minutes after exercise is stopped. Performing PF tests immediately after exercise is stopped may be artificially low due to exhaustion. • Another appropriate post-exercise testing schedule is 5, 10, 15, 20, and 30 minutes after cessation of exercise (52). • Following patients for more than 30 minutes is controversial (76, 77). 3. Spirometry: • Performed according to ATS/ERS recommendations (67). • At least two and preferably three acceptable tests should be obtained at each testing interval. • As a goal, the highest and second highest FEV 1 values should differ by no more than 0.150 L. • The highest of the acceptable FEV 1 values is selected as the representative value at each interval. • If FEV 1 has returned from its nadir (low-point) to the baseline level or greater, spirometry testing can be terminated at 20 minutes post-exercise.

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