The Effects of Milrinone and Its Mechanism in the Fatigued Diaphragm in Dogs
The Effects of Milrinone and Its Mechanism in the Fatigued Diaphragm in Dogs
复制标题
米力农对犬膈肌疲劳的作用及其机制
作者：
Y. Fujii;Shinji Takahashi;H. Toyooka
我们研究了米力农对非疲劳和疲劳膈肌的作用及其机制，在Ia组（n = 5）中，无疲劳的动物（定义为无法维持肌肉力量）仅接受维持液。在Ib组（n = 5）中，对无疲劳的犬进行快速推注（50 [micro sign]g/kg），然后连续输注（0.5 [micro sign]g [center dot] kg-1 [center dot] min-1）米力农。IIa、IIb和IIc组（每组n = 8），通过间歇性超大双侧膈电刺激（频率为20 Hz，持续30 min）诱导疲劳。产生疲劳后，仅给予维持液（IIa组）;米力农（50 [微符号]g/kg负荷剂量加0.5 [微符号]g [中心点] kg-1 [中心点] min-1维持剂量）（IIb组）;或尼卡地平5 [micro sign]g [center dot] kg（-1）[center dot] min-1与米力农同时输注（IIc组）。膈肌收缩力用跨膜压（Pdi）评估。在Ia组和Ib组中未观察到Pdi差异。疲劳产生期后，在低频率（20-Hz）刺激下，IIa、IIb和IIc组的Pdi较疲劳前值降低（P < 0.05），而在高频率（100-Hz）刺激下降低幅度最小。与Ⅱ a组相比，Ⅱ b组输注米力农时各刺激的Pdi均增加（P < 0.05）。在IIc组中，米力农对疲劳膈肌Pdi的增强作用在尼卡地平给药后并未消失。总之，米力农改善疲劳犬膈肌的收缩性，但不是通过其对跨膜钙运动的影响。结论：膈肌疲劳可能导致呼吸衰竭的发生。米力农可增加疲劳膈肌的收缩力，从而对改善膈肌疲劳具有变力作用。（Anesth Analg 1998;87：1077-82）
We studied the effects of milrinone and its mechanism in nonfatigued and fatigued diaphragms in dogs.In Group Ia (n = 5), animals without fatigue, defined as the inability to sustain muscle force, received only maintenance fluids. In Group Ib (n = 5), dogs without fatigue were given a bolus injection (50 [micro sign]g/kg) followed by continuous infusion (0.5 [micro sign]g [center dot] kg-1 [center dot] min-1) of milrinone. In Groups IIa, IIb, and IIc (n = 8 in each), diaphragmatic fatigue was induced by intermittent supramaximal bilateral electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. After producing fatigue, only maintenance fluids were administered (Group IIa); milrinone (50 [micro sign]g/kg loading dose plus 0.5 [micro sign]g [center dot] kg-1 [center dot] min-1 maintenance dose) was administered (Group IIb); or nicardipine 5 [micro sign]g [center dot] kg (-1) [center dot] min-1 was infused simultaneously with milrinone (Group IIc). Diaphragmatic contractility was assessed with transdiaphragmatic pressure (Pdi). No differences in Pdi were observed in Groups Ia and Ib. After the fatigue-producing period, Pdi at low-frequency (20-Hz) stimulation decreased from the prefatigued values in Groups IIa, IIb, and IIc (P < 0.05), whereas the decrease was minimal at high-frequency (100-Hz) stimulation. Compared with Group IIa, Pdi to each stimulus increased during milrinone infusion in Group IIb (P < 0.05). In Group IIc, the augmentation of Pdi in the fatigued diaphragm by milrinone was not abolished with an administration of nicardipine. In conclusion, milrinone improves contractility in the fatigued canine diaphragm but not via its effect on transmembrane calcium movement. Implications: Diaphragmatic fatigue may contribute to the development of respiratory failure. Milrinone increases contractility in the fatigued diaphragm and thereby may have an inotropic action on the improvement of diaphragmatic fatigue. (Anesth Analg 1998;87:1077-82)
米力农和多巴酚丁胺治疗严重心力衰竭：不同的血流动力学效应和个体患者的反应性。
影响因子：
37.8
作者：
Colucci,WS;Wright,RF;Jaski,BE;Fifer,MA;Braunwald,E
通讯作者：
Braunwald,E