The Effect of EDP on Diaphragmatic Function and Neural Respiratory Drive in Patient With AECOPD

The Effect of External Diaphragmatic Pacemaker(EDP) on Diaphragmatic Function and Neural Respiratory Drive in Patient With Acute Exacerbation of Chronic Obstructive Pulmonary Disease(AECOPD)

Chronic Obstructive Pulmonary Disease (COPD) is a common respiratory disease characterized by airflow limitation that is progressive and not fully reversible. Patients with acute exacerbation of COPD must be hospitalized, as for further increase in airway resistance, pulmonary alveolar excessive expansion, diaphragm fatigue and neural respiratory drive. In recent years, Pulmonary rehabilitation is recognized as a core component in the comprehensive management of COPD, EDP as a means of rehabilitation can alleviate diaphragmatic fatigue, improve ventilation function, reduce the neural respiratory drive in patients with COPD during hospitalization, but still lack of evidence based medicine. Surface EMGdi can accurately evaluate neural respiratory drive, its detection is non-invasive, simple and safety .Therefore,Neural respiratory drive by surface EMGdi can be used as an important index for evaluating the therapeutic efficacy of AECOPD patients during hospitalization. In the present study, about 40 patients with COPD will be recruited as research subjects .And the investigators aim to explore the effect of EDP on diaphragmatic function and neural respiratory drive in patient with AECOPD.Contrast analysis will be conducted to evaluate the effects of EDP on patients with AECOPD, which may provide a reasonable basis for the clinical application of EDP to AECOPD patients.

Patients with AECOPD will participate in a rehabilitation program for one week. Participants in the proposed study will be randomly divided into two intervention groups:controlgroup and EDP therapy group. Before using EDP,the investigators will measure the relevant parameters of lung volume , diaphragm electromyogram, diaphragm activity and other basline index. Then EDP will be applied to investigate the effects of EDP on the above mentioned respiratory mechanics parameters.

30 minutes continuous stimulation each time, two times a day, a total of one weeks of treatment .Parameters: 30min stimulation time, pacing frequency of 9 beats / min, pulse frequency is 40 hertz, the stimulus intensity (output pulse amplitude) is in the range of 0~30 units, which should be adjusted according to the daily maximum tolerance (patients with no pain and tension).

Turn on the device, and clean the skin where the patch will be located according to the screen tip. Paste the two groups of small electrodes to the inferior 1/3 of the outer edge of bilateral sternocleidomastoid, and the large electrodes are pasted to the corresponding 2nd intercostal skin surface of pectoralis major at midclavicular line.Adjusting the stimulus intensity according to the daily maximum tolerance (patients with no pain and tension).30 minutes continuous stimulation each time, twice a day, a total of one weeks of treatment .

Diaphragmatic function can be assessed by surface diaphragm electromyogram (EMGdi), which reflect the physiological activity of the diaphragm and indicate functional status of the neural respiratory drive.

Pulmonary function is measured using a spirometer(PonyFX 229, Cosmed, Rome, Italy) that is calibrated daily.The FEV1 and percent-of-predicted FEV1, FVC and percent-of-predicted FVC which are presented in one report are used to evaluate Pulmonary Function.

Exercise capacity is evaluated using the 6-min walking distance (6MWD) according to American Thoracic Society guidelines.

The degree of activity of the left and right diaphragmatic muscles in the general breath and deep breath were measured respectively.

The changes of diaphragm thickness of the left and right diaphragmatic muscles in the breath were measured respectively.

Currently, the maximal inspiratory pressure (PImax) and maximal expiratory pressures(PEmax) are measured by a digital manometer (AZ-8205, AZ Instrument, Taichung City, Taiwan)and combined to evaluate inspiratory muscle function.

Body composition abnormalities are prevalent in COPD.Human body composition analyzer can detect various elements of human body and analyze human health status.

Health-related quality is a component of the broader concept of quality of life and is defined as satisfaction with health.The St. George's Respiratory Questionnaire (SGRQ) and Chronic Respiratory Disease Questionnaire (CRQ）;and its self-reported version are the most widely used disease-specific questionnaires.

Individuals with chronic respiratory disease often have symptoms such as dyspnea, fatigue, cough, weakness,sleeplessness,and psychological distress.Instruments for assessment of multiple symptoms include COPD Assessment Test (CAT) and Modified Medical British Research Council Scale(mMRC).

Inclusion Criteria: Patients with pulmonary function test of forced expiratory volume at one second (FEV1)/forced vital capacity(FVC) < 70% after inhalation of bronchial dilation agent. Patients in a clinically acute exacebation state. Exclusion Criteria: Patients were excluded if they had evidence of pneumothorax or mediastinal emphysema and pacemaker installed. Patients with acute cardiovascular event and severe cor pulmonale. Patients with poor compliance. An Other causes of diaphragmatic dysfunction.