Conducting the test Copy TEST COURSE Jan 2023

Conducting the test

Pretest preparation

Medication

The decision to withhold long- and short-acting bronchodilators before testing is a clinical one determined by the referring healthcare professional. It is very important to document what medication, the type and dosage, and when it was last taken prior to testing so that the test can be interpreted correctly. Short-acting inhaled drugs (e.g. salbutamol or ipratropium bromide) should not be used within 4 hours of testing. Long-acting beta-agonists should be stopped for 12 hours prior to the test. If medication has been taken, the operator should record the name, dosage and the time of last administration of any medication that may alter lung function, particularly bronchodilator medication.

Performing the test

Wash hands and ask subject to wash hands
Conduct baseline spirometry
Ensure 3 acceptable and repeatable baseline blows are recorded
Explain the procedure to the subject
Explanation about the effects of the bronchodilator which include possible tachycardia, sensation of the heart beating in their chest. These are normal effects but are not experienced by all subjects
Ensure that the above washout timeframes have been adhered to

Administer the bronchodilator

Administer 4 metered doses of a salbutamol bronchodilator (400ug) 100ug at a time, with 30 second rests between doses via a valved spacer (A lower dose can be used if there is a concern about any effect on heart rate). This is achieved as follows:

Assemble the spacer
Remove inhaler cap
Hold inhaler upright and shake well
Insert inhaler upright into spacer
If the spacer is being used for the first time after having been disinfected (this should happen for each new subject), prime it by spraying 4 puffs of Salbutamol into the closed chamber

Administer the medication to the subject

Put mouthpiece between teeth (without biting) and close lips to form good seal
Breathe out gently, into the spacer Keep spacer horizontal and press down firmly on inhaler canister once so that a dose of 100ug of salbutamol is given
Breathe in slowly and deeply to fully inflated lungs
Hold breath for 10 seconds before exhaling
While holding breath, remove spacer from mouth
Breathe out gently
Remove inhaler from spacer. Wait 30 seconds
Repeat all steps starting above for a second time, then a third then a fourth time
Replace inhaler cap
Four separate doses (total dose 400ug) are delivered at 30 second intervals. (A lower dose can be used if there is a concern about any effect on heart rate)
Wait a minimum of 15 minutes for SABA to take effect

Post bronchodilator spirometry

After 15 to 30 minutes retest the subject
Ensure 3 acceptable and repeatable blows are recorded
Ask the subject to remove the mouthpiece and discard in the biohazardous waste bag
Wash hands and ask subject to wash his hands
Wipe the spirometer with a disinfectant wipe
Evaluate the results by comparing the best pre and the best post FEV1 (and or FVC) for a change of 12% and 200mls