Acute Effects of a Flutter Device in COPD
Acute Effects of a Flutter Device in COPD
Chronic obstructive pulmonary disease (COPD) is characterised by airflow limitation that is
 not fully reversible, and is usually progressive and associated with an abnormal inflammatory
 response of the lungs to noxious particles or gases, most commonly cigarette smoking. The
 disease affects not only the large central airways but also the small, more peripheral
 airways deeper into the lung, defined as less than 2 mm in diameter.

 Besides medical treatment, physiotherapy plays a major role in treatment and various methods
 have been suggested to remove airway of secretions. The flutter is a simple and small device
 shaped like a pipe that creates a positive expiratory pressure (PEP) and high frequency
 oscillation when the expired air passes through it. These vibrations are thought to mobilise
 airway secretions facilitating their clearance and improving breathing.

 Standard blowing tests, like spirometry, where patients blow forcedly into a machine, have
 previously been used to investigate the efficacy of flutter devices. However, spirometry
 assesses the damage of larger airways but not small airways, also known as the "silent zone"
 which, crucially, are specifically damaged in COPD.

 In this study the investigators hypothesise that because the flutter helps clear the airways
 from the excessive thick mucus produced by COPD patients, these patients may find it easier
 to breathe and have lower resistance to moving air in and out of their lungs.

 The main objective of this study is to compare the effect of a flutter or a sham device on
 small airways damage using impulse oscillometry (IOS), a non-invasive method that, contrary
 to other common blowing tests, measures small airway resistance during normal breathing.

 In addition, because COPD is characterised by inflammation, the investigators would also like
 to measure a gas the patients blow out, nitric oxide (NO) the levels of which reflect airway
 inflammation. This will give to investigators an insight into the relationship between airway
 inflammation and small airway function.
Chronic obstructive pulmonary disease (COPD) is characterised by airflow limitation that is
 not fully reversible. This limitation is usually progressive and associated with an abnormal
 inflammatory response of the lungs to noxious particles or gases.

 Patients suffering from COPD may show pathologic changes not only in the large but also in
 the small airways, which are defined as less than 2mm in diameter. Airway inflammation may
 cause increased thick mucus secretions which can narrow the airways increasing the resistance
 to the airflow.

 Physiotherapy to remove secretions is indicated for patients with COPD who have regular
 sputum or those with thick secretions and various techniques and physiotherapy devices can be
 applied for the removal of secretions. The flutter is a simple and small device shaped like a
 pipe that creates a positive expiratory pressure (PEP) and high frequency oscillation as
 expired air passes through it. These vibrations and PEP are thought to mobilise airway
 secretions facilitating their clearance and improving airflow.

 The effects of the flutter device have been studied in different patient groups, but
 especially in lung diseases characterised by mucus hypersecretion such as COPD, cystic
 fibrosis and bronchiectasis. In COPD, even though the flutter device increases the volume of
 expectorated secretions, its beneficial effects on pulmonary function as assessed by
 spirometry and plethysmography are inconclusive. However, these standard lung function tests
 (such as spirometry) asses the large airways, but do not provide an accurate estimate of the
 small airways which have been described by some authors as "the silent zone".

 The investigators hypothesise that the use of impulse oscillometry (IOS), a non-invasive
 technique that provides information on small airway resistance during normal breathing, may
 reveal the effect of the flutter device which may have not been accurately measured by
 spirometry in previous studies.

 In addition, the investigators would like to measure exhaled nitric oxide (NO) levels which
 reflect airway inflammation and may therefore be useful to determine the association between
 small airway disease and inflammation.

 In summary, the symptoms of patients with COPD improve following breathing exercises with a
 flutter device, however, the effect of this device on lung function is unclear. The
 investigators hypothesise that the combined use IOS and NO, would help understand and
 quantify the effects of the flutter device on the small airways disease in COPD.

 The main objective of this study is to measure the effect of a 30 minutes breathing exercise
 with a flutter device on airway resistance as assessed by impulse oscillometry in patients
 with COPD.

 The secondary objective is to investigate the association between inflammation, airway
 resistance and volume of secretions in COPD patients.
Inclusion Criteria:

 - patients with COPD meeting the Global Initiative for Obstructive Lung Disease (GOLD)
 guidelines, with forced expiratory volume in the first second of expiration (FEV1) <80%
 predicted, FEV1/FVC ratio <70% predicted (FVC= forced vital capacity), and total lung
 capacity (TLC) >80% predicted), with or without sputum, will be included.

 The severity of COPD will be classified according to GOLD criteria:

 Stage I: mild FEV1/FVC<0.70 and FEV1>80% predicted; Stage II: moderate FEV1/FVC<0.70 and
 50<FEV1<80% predicted; Stage III: severe FEV1/FVC<0.70 and 30<FEV1<50% predicted; Stage IV:
 very severe FEV1/FVC<0.70 and FEV1<30% or FEV1<50% predicted plus chronic respiratory
 failure,

 Exclusion Criteria:

 Patients with:

 -  Upper respiratory tract infection within the previous 28 days

 -  Treatment with antibiotics within 4 weeks prior the study

 -  Acute dyspnoea or hemoptysis

 -  Chest pain or recent history of rib fracture or pneumothorax

 -  Acute cardiovascular events in the previous 3 months

 -  Any history or evidence of renal, gastrointestinal or hepatic disease

 -  Any history and evidence of neuropsychiatric disease

 -  Alcohol, drug abuse or any other condition associated with poor compliance

 -  Breast feeding

 -  Pregnancy

 -  Other complications that hinder the completion of the tests

 -  Unable to provide written informed consent