Surface electromyography of accessory inspiratory muscle activity during upper airway obstruction

In a previous study, we examined how changes in breathing pattern affect the electromyographic (EMG) activity of accessory inspiratory muscles during spontaneous breathing. The present study aimed to create a device that simulates progressive upper airway obstruction to examine how such obstruction relates to EMG changes and respiratory movement. The subjects were 8 men and women between 26 and 47 years of age with normal cardiopulmonary function. A two-in-one airway pressure and flow monitor mask and a pulse oximeter were secured to the subjects, and electrodes were placed bilaterally on the sternocleidomastoid muscles. A heat and moisture exchange filter was attached to the tip of the airway pressure and flow monitor, and 1 mL/min of 2% methylcellulose solution was injected into the filter using a syringe pump. As airway resistance gradually increased over time, changes in accessory inspiratory muscle activity, airway pressure, expiratory flow, and percutaneous oxygen saturation were measured. Following spike count processing, changes in the spike count were calculated at one-minute intervals. Spike counts for the intervals between 5 and 6 minutes and 6 and 7 minutes were significantly greater than for the other intervals. Whereas the average airway pressure among all subjects increased over time, and increased significantly starting from the interval between 4 and 5 minutes, expiratory flow significantly decreased starting from this same interval. SpO_2 started to decrease from the interval between 5 and 6 minutes and was significantly lower over the next interval. These findings indicate that the sternocleidomastoid muscle may be actively recruited as an accessory inspiratory muscle during inspiratory movement associated with increased airway resistance. Furthermore, given the significant EMG changes observed before SpO_2 decreased, electromyography may be a more sensitive monitoring method of upper airway obstruction than pulse oximetry.

2014年度

収集根拠 : 博士論文（自動収集）
資料形態 : テキストデータ
コレクション : 国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文
In a previous study, we examined how changes in breathing pattern affect the electromyographic (EMG) activity of accessory inspiratory muscles during spontaneous breathing. The present study aimed to create a device that simulates progressive upper airway obstruction to examine how such obstruction relates to EMG changes and respiratory movement. The subjects were 8 men and women between 26 and 47 years of age with normal cardiopulmonary function. A two-in-one airway pressure and flow monitor mask and a pulse oximeter were secured to the subjects, and electrodes were placed bilaterally on the sternocleidomastoid muscles. A heat and moisture exchange filter was attached to the tip of the airway pressure and flow monitor, and 1 mL/min of 2% methylcellulose solution was injected into the filter using a syringe pump. As airway resistance gradually increased over time, changes in accessory inspiratory muscle activity, airway pressure, expiratory flow, and percutaneous oxygen saturation were measured. Following spike count processing, changes in the spike count were calculated at one-minute intervals. Spike counts for the intervals between 5 and 6 minutes and 6 and 7 minutes were significantly greater than for the other intervals. Whereas the average airway pressure among all subjects increased over time, and increased significantly starting from the interval between 4 and 5 minutes, expiratory flow significantly decreased starting from this same interval. SpO_2 started to decrease from the interval between 5 and 6 minutes and was significantly lower over the next interval. These findings indicate that the sternocleidomastoid muscle may be actively recruited as an accessory inspiratory muscle during inspiratory movement associated with increased airway resistance. Furthermore, given the significant EMG changes observed before SpO_2 decreased, electromyography may be a more sensitive monitoring method of upper airway obstruction than pulse oximetry.
2014年度

収集根拠 : 博士論文（送信）
資料形態 : テキストデータ
コレクション : 国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文
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