Measuring airway smooth muscle using optical coherence tomography in patients undergoing bronchoscopy – an observation study.

We aim to measure the area of airway smooth muscle in large and small airways of patients undergoing bronchoscopy. The bronchoscopies will be performed by clinicians experienced in interventional bronchoscopy and are all employed by the WA Department of Health. They will also undertake the PS-OCT probe procedure. They will introduce the catheter containing the optic fibre through the bronchoscope into the airway and maintain the bronchoscope and catheter in place while measurements are made and data collected by the engineer / biophysicist. This procedure will add an extra 10-15 minutes to the duration of the procedure, which normally takes around 25 minutes. Apart from adding time to the procedure, there are no significant risks associated with the planned PS-OCT measurements. The optical fibre is enclosed in a soft plastic catheter (sheath) and the laser is non-heating and will not damage the airway wall. The catheter will be passed out into the small (2 mm diameter) airways. Adverse events or serious adverse events will be assessed by the non-medical and medical investigators and, if necessary, immediate counselling or first aid will be administered. Serious adverse events will be immediately referred to the emergency on-call team with specialist intervention (e.g. emergency department or intensive care teams) as appropriate. All adverse events or serious adverse events (those requiring medical assessment or admission to hospital) will be recorded on the Adverse Events form. This form will be submitted to the Human Research Ethics Committee as part of quarterly reporting (non-serious adverse events) or within 24 hours (serious adverse events). Follow-up of adverse events will be by the investigators in the first instance and by the usual medical team or appropriate medical team (e.g. emergency medical staff) in the case of a serious adverse event. All adverse events will be recorded in the participant study file and followed until resolution. Participants will be studied in the hospital setting, currently approved at Sir Charles Gairdner Hospital and in the future, will be at Fiona Stanley Hospital as well. Participants will be initially informed of the study by the doctor who will perform the bronchoscopy. These doctors are participating as investigators in this study. Patients who agree to learn more about the study will then be contacted by a post-doctoral researcher to discuss the study in detail. Prior to the bronchoscopy, the researcher will provide patient information sheets, answer questions pertaining to the study and obtain informed consent. Participants will also fill in a Respiratory Health questionnaire. After informed consent is obtained, the researcher will collect participant medical history as well as lung function measurements. Additional time taken for the above-mentioned recruitment procedure will take about 30 minutes.