The Effect of Transcranial Direct Current Stimulation (tDCS) on Dyspnoea Perception, Pulmonary Function and Functional Level During COPD Exacerbation

The Effect of Transcranial Direct Current Stimulation (tDCS) on Dyspnoea Perception, Pulmonary Function and Functional Level During COPD Exacerbation

Chronic obstructive pulmonary disease (COPD) is a treatable disease characterized by irreversible and progressive airflow limitation, which is a cause of high morbidity and mortality. Dyspnea is an important component of COPD exacerbations that changes functional level and prognosis and limits the patient's quality of life and activities of daily living. Since COPD patients complain a lot of dyspnea associated with reduced exercise capacity and worsening lung function, there is a great need to develop effective physiologically based rehabilitation techniques to restore the dysfunctional respiratory motor system. Evidence supporting the importance of task-specific training based on neural plasticity also applies to pulmonary rehabilitation for COPD. Alterations in neuroplasticity and cortical excitability, tDCS is a promising technique for modulating brain activity. As a painless, easy-to-use and noninvasive technique, tDCS has shown efficacy in relieving pain, which shares the same neural substrates as dyspnea. Similarities have been established between the pathophysiology of dyspnea and pain. Close or even overlapping activation zones of brain structures involved in the integration of pain and dyspnea have been emphasized. Therefore, it is hypothesized that tDCS stimulation of areas where one or more of these cerebral structures are activated in pain may also have an effect on dyspnea. In light of this information, researchers believe that relieving dyspnea with tDCS will have an impact on the prognosis of patients during COPD exacerbations. In this context, researchers will evaluate the effects of tDCS on dyspnea perception, lung function, and functional level in patients with COPD exacerbation. When the literature was reviewed, no study on the use of tDCS in COPD patients was found. The use of tDCS as a non-invasive and easy-to-use effective treatment method with neuro-modulation to combat dyspnea and functional level in COPD patients constitutes the originality of the study.

Forty patients who were hospitalized in the Chest Diseases Service due to COPD exacerbation and met the inclusion criteria will be included in the study. The evaluation parameters included symptom assessment, breathlessness perception questionnaire, COPD assessment test, peripheral muscle strength assessment, grip strength assessment, pulmonary function test, Montreal cognitive assessment test, London chest activities of daily living scale, timed up and go test, hospital anxiety and depression scale, respiratory muscle strength, fNIRS and capnography. Assessments will take place before and after treatment. Sham (n:20) group will receive conventional physiotherapy and sham tDCS, while the Study (n:20) group will receive tDCS and conventional physiotherapy. For anodal tDCS, the anode electrode will be placed over the left primary motor cortex and the cathode will be placed over the right supraorbital region. For the study group, tDCS application will be applied with a current of 2 mA for 30 minutes on 3 consecutive days. In the sham group, tDCS application will be increased to 2 mA for the first 30 seconds and then decreased to 0 mA within 30 seconds after receiving current for 15 seconds. The electrodes will remain on the patient's head for the rest of the time (30 minutes in total).

In conclusion, the effects of tDCS on dyspnea perception, pulmonary function and functional level in COPD exacerbation period patients will be investigated. At the same time, the advantages of tDCS administration in COPD patients will be evaluated by examining its effects on cerebrovascular responses, tissue oxygenation, muscle strength, cognitive level, activity of daily living, anxiety and depression. It will provide different perspectives to clinicians and researchers who will create evaluation, treatment and study plans for COPD exacerbation period patients with limited treatment options and will be a guide for new research.

Inclusion Criteria:

• Diagnosed with COPD and followed up for at least 6 months
• Hospitalised due to an exacerbation
• Have not taken any medication affecting the nervous system in the last 6 months
• Co-operative
• Have the ability to participate in working procedures
• Over 18 years of age,
• The specialist physician finds it suitable for physiotherapy applications,
• Volunteers who want to participate in the study

Exclusion Criteria:

• Having comorbidities other than COPD, such as bronchiectasis, lung cancer or asthma
• Surgery in the last 6 months (volume reduction surgery, etc.)
• Neuromuscular disease
• Pulmonary embolism or pulmonary oedema
• Presence of cranial, cardiac, spinal cord, intra-aural metal implants
• Epilepsy
• Patients on invasive mechanical ventilation
• Patient with cardiac pace maker