Clement M G, Mortola J P, Albertini M, Aguggini G
J Appl Physiol (1985). 1986 Jun;60(6):1992-9. doi: 10.1152/jappl.1986.60.6.1992.
We have examined breathing patterns and respiratory mechanics in anesthetized tracheostomized newborn piglets and adult pigs and the changes determined by cervical bilateral vagotomy. Piglets had a respiratory system compliance and resistance, on a per kilogram basis, respectively, higher and smaller than the adults. After vagotomy neither variable changed in the newborn, but resistance dropped in the adult. This may suggest that efferent vagal control of bronchomotor tone is more pronounced in the adult. Respiratory system time constant was longer in newborns both before and after vagotomy. The distortion of the chest wall, examined as the ratio between the volume inhaled spontaneously and the passive volume for the same abdominal motion, was more marked in newborns, reflecting their higher chest wall compliance. The work per minute, computed from the pressure and volume changes, was larger in piglets. After vagotomy the external work per minute was not different; however, the larger tidal volumes were accompanied by a larger chest distortion. This may indicate that vagal control of the breathing pattern, by limiting the depth of inspiration and hence the amount of chest distortion, has implications on the energetics of breathing.
我们研究了麻醉状态下气管切开的新生仔猪和成年猪的呼吸模式及呼吸力学，以及双侧颈迷走神经切断术所导致的变化。按每千克体重计算，仔猪的呼吸系统顺应性高于成年猪，而阻力则小于成年猪。迷走神经切断术后，新生仔猪的这两个变量均未改变，但成年猪的阻力下降。这可能表明，迷走神经对支气管运动张力的传出控制在成年猪中更为显著。迷走神经切断术前和术后，新生仔猪的呼吸系统时间常数均较长。以自主吸入体积与相同腹部运动时的被动体积之比来衡量的胸壁变形，在新生仔猪中更为明显，这反映出它们较高的胸壁顺应性。根据压力和体积变化计算得出，仔猪每分钟的呼吸功更大。迷走神经切断术后，每分钟的外部呼吸功没有差异；然而，较大的潮气量伴随着更大的胸壁变形。这可能表明，迷走神经通过限制吸气深度从而限制胸壁变形量来控制呼吸模式，这对呼吸能量学有影响。
