Gigliotti F, Gurrieri G, Duranti R, Gorini M, Scano G
Istituto di Clinica Medica III, Università degli Studi, Florence, Italy.
Eur Respir J. 1993 Mar;6(3):371-7.
Broxaterol, a new selective beta 2-agonist, has been shown to exert inotropic effects on both fresh and fatigued canine diaphragm. We evaluated the effect of broxaterol on the activation and force output of the respiratory muscles in patients with chronic obstructive pulmonary disease (COPD). We studied 9 patients with moderate to severe COPD. Each patient was infused with saline and Broxaterol (200 micrograms) in saline alternately. We measured lung volumes, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), breathing pattern, P0.1, respiratory muscle EMG (diaphragm, EMGd, and parasternal, EMGp) and P0.1/EMGd ratio. Measurements were made under control conditions and at 15, 30, 60, and 120 min after each infusion. Broxaterol, but not saline, resulted in a slight but significant increase in vital capacity (VC), forced expiratory volume in one second (FEV1) and MIP, and a decrease in functional residual capacity (FRC). Breathing pattern did not change, while EMG significantly decreased, and P0.1/EMGd significantly increased in 5 of the 9 patients after broxaterol. These data seem to indicate that by partially unloading the respiratory muscles, broxaterol results in decreased muscle activation (EMG). Increase in chest wall neuromuscular coupling (P0.1/EMGd) may also be observed.
溴沙特罗是一种新型选择性β2激动剂，已被证明对新鲜和疲劳的犬膈肌均有正性肌力作用。我们评估了溴沙特罗对慢性阻塞性肺疾病（COPD）患者呼吸肌激活和力量输出的影响。我们研究了9例中重度COPD患者。每位患者交替输注生理盐水和含溴沙特罗（200微克）的生理盐水。我们测量了肺容积、最大吸气压力（MIP）、最大呼气压力（MEP）、呼吸模式、P0.1、呼吸肌肌电图（膈肌，EMGd，和胸骨旁，EMGp）以及P0.1/EMGd比值。在对照条件下以及每次输注后15、30、60和120分钟进行测量。溴沙特罗而非生理盐水导致肺活量（VC）、一秒用力呼气容积（FEV1）和MIP略有但显著增加，功能残气量（FRC）降低。呼吸模式未改变，而在9例患者中有5例在输注溴沙特罗后肌电图显著降低，P0.1/EMGd显著增加。这些数据似乎表明，通过部分减轻呼吸肌负荷，溴沙特罗可导致肌肉激活（肌电图）降低。也可能观察到胸壁神经肌肉耦联增加（P0.1/EMGd）。
