Tomori Z, Donic V, Kurpas M
Dept of Pathophysiology, Faculty of Medicine, Safárik University, Kosice, Czechoslovakia.
Eur Respir J. 1993 Jan;6(1):53-9.
The changes in airway occlusion pressure and airflow, occurring during two spasmodic breathing patterns, were studied and compared with normal breathing pattern in 12 anaesthetized cats. The inspiratory effort developed during the sniff-like aspiration reflex elicited by mechanical stimulation of the nasopharynx under control conditions proved to be very similar in character and intensity to the activity observed during gasping which occurred on resuscitation, of the same cats, from hypoxic apnoea. The starting (P50) and maximum (Pmax) airway occlusion pressure developed in these two spasmodic breathing patterns were very high. Extremely rapid rates of contraction and relaxation were detected by computer-assisted measurements of dynamic changes in both the pressure values and the slopes of pressure curves. The results suggest common effector mechanisms, reflecting similar forceful inspiratory drives, for the aspiration reflex and gasping. These two spasmodic processes differ substantially from normal breathing. Nevertheless, the aspiration reflex differs from gasping in that it can be elicited by activation of upper airway afferents during eupnea. Moreover, as yet, there is no definitive evidence that the brainstem mechanisms responsible for generating the aspiration reflex are the same as those of the gasp. The main benefits of this reflex are its rather easy elicitability under various conditions and its capability to induce important cardiorespiratory effects (e.g.) reversal of central apnoea) owing to its powerful activity.
研究了12只麻醉猫在两种痉挛性呼吸模式下气道阻塞压力和气流的变化，并与正常呼吸模式进行了比较。在对照条件下，通过机械刺激鼻咽引发的类似吸气的抽吸反射过程中产生的吸气努力，在性质和强度上与同一组猫从低氧性呼吸暂停复苏时发生的喘息过程中观察到的活动非常相似。在这两种痉挛性呼吸模式中产生的起始气道阻塞压力（P50）和最大气道阻塞压力（Pmax）非常高。通过计算机辅助测量压力值和压力曲线斜率的动态变化，检测到极其快速的收缩和松弛速率。结果表明，抽吸反射和喘息存在共同的效应机制，反映了相似的强力吸气驱动。这两种痉挛性过程与正常呼吸有很大不同。然而，抽吸反射与喘息的不同之处在于，它可以在平静呼吸时通过激活上呼吸道传入神经而引发。此外，目前尚无确凿证据表明负责产生抽吸反射的脑干机制与喘息的脑干机制相同。这种反射的主要优点是在各种条件下相当容易引发，并且由于其强大的活动能力，能够诱发重要的心肺效应（例如，逆转中枢性呼吸暂停）。
