On the 7th of July, as part of the King’s College Muscle Lab Student Panel session, we looked at measuring lung function in two ways, Impulse Oscillometry and Spirometry.
Impulse Oscillometry involved measuring the patient’s tidal breathing over 90 seconds at a 5Hz resistance. We felt the procedure was simple, and once you get used to the noise of the machine, easy to get good readings from. We repeated the examination 3 times, layering the graphs to ensure our results were concordant. We saw a regular trace graph over a 90 second period.
Spirometry was a little more difficult to carry out; we recorded some tidal breathing first to ensure the patient was comfortable and ready, then the patient was asked to inhale as much air as possible into the lungs, then exhale as quickly as possible, all air from their lungs (we encouraged this through shouting as we found the first time round both patients didn’t expel as much air as they could!). This gave us a forced expiratory volume in 1 second value. We also repeated this examination to ensure out results agreed.
Both these tests are good in determining aspects of airway function, with Spirometry also giving FEV1 values and vital capacity, and Impulse Oscillometry giving tidal breathing patterns, however for patients with breathlessness which is a common symptom seen in the chest clinic, these tests could be difficult to carry out and gain accurate results, especially from Spirometry. Also young children may find this difficult to carry out, as it can take a while to get used to breathing with your mouth round the mouthpiece and with a nose clip. Overall it was a good experience to get some practical skills in the clinic and gain some valid result and values to analyse.
Estelle Thomas, Year 12, Harris Academy Crystal Palace