Morel D R, Forster A, Bachmann M, Suter P M
J Appl Physiol Respir Environ Exerc Physiol. 1984 Oct;57(4):1104-10. doi: 10.1152/jappl.1984.57.4.1104.
Breathing pattern, thoracoabdominal motion, and separate end-expiratory positions of the rib cage and abdomen were measured noninvasively in eight healthy subjects before and after intravenous administration of either placebo or midazolam, a short-acting benzodiazepine. Compared with placebo, midazolam produced a significant (P less than 0.01) decrease in mean inspiratory flow of 29% from preinjection values, resulting in a 39% reduction in tidal volume (VT). This ventilatory depression was partly compensated by a 35% decrease in expiratory time producing an increase in respiratory rate (+39%). The fall in VT was almost entirely (91%) mediated by a reduction of the abdominal contribution to tidal breathing while sparing rib cage motion. This fact contrasts with the effects of inhalational anesthetics or morphine, which preferentially depress rib cage expansion, indicating that thoracoabdominal motion may selectively be depressed by different pharmacological agents. In addition, continuous recording of end-expiratory levels showed a significant transient fall in the rib cage's end-tidal position 2 min after midazolam administration associated with the occurrence of central apneas.
在8名健康受试者静脉注射安慰剂或短效苯二氮䓬类药物咪达唑仑之前和之后，对其呼吸模式、胸腹运动以及胸廓和腹部的呼气末独立位置进行了无创测量。与安慰剂相比，咪达唑仑使平均吸气流量较注射前值显著降低（P<0.01）29%，导致潮气量（VT）降低39%。这种通气抑制部分通过呼气时间减少35%得到代偿，使呼吸频率增加（+39%）。VT的下降几乎完全（91%）是由于腹部对潮式呼吸的贡献减少，而胸廓运动未受影响。这一事实与吸入性麻醉药或吗啡的作用形成对比，后者优先抑制胸廓扩张，表明不同的药理药物可能选择性地抑制胸腹运动。此外，呼气末水平的连续记录显示，咪达唑仑给药2分钟后胸廓的呼气末位置出现显著短暂下降，与中枢性呼吸暂停的发生有关。
