Adams J A, Mangino M J, Bassuk J, Sackner M A
Division of Neonatology, Mount Sinai Medical Center, Miami Beach, Florida 33140, USA.
J Appl Physiol (1985). 2000 Dec;89(6):2447-52. doi: 10.1152/jappl.2000.89.6.2447.
The hemodynamic effects of periodic acceleration (pG(z)), induced in the spinal axis with noninvasive motion ventilation (NIMV), were studied in a piglet model of pulmonary hypertension associated with meconium aspiration. Animals (n = 12) were anesthetized, paralyzed, intubated, and supported by conventional mechanical ventilation (CMV). Thirty minutes after tracheal instillation of meconium solution (6 ml/kg), either CMV (n = 6) was continued or NIMV (n = 6) was initiated. Changes in systemic and pulmonary hemodynamics and arterial blood gases were tracked for 2 h after aspiration. Thermodilution, cardiac output, and heart rate were not significantly different after meconium aspiration in the pG(z) group relative to the CMV controls. Aortic pressure and systemic vascular resistance were significantly lower (approximately 30%) after meconium aspiration in NIMV animals relative to CMV animals. Pulmonary arterial pressure and pulmonary vascular resistance were also significantly lower, by 100%, after aspiration of meconium in the NIMV animals compared with the CMV controls. Meconium aspiration significantly decreased total respiratory compliance by approximately 50% and increased total respiratory resistance by approximately 100% in both CMV and NIMV animals, but such alterations did not differ between the two groups. Both CMV and NIMV satisfactorily supported ventilation in these paralyzed animals. In conclusion, NIMV through pG(z) in the spinal axis decreased systemic and pulmonary vascular resistance in piglets after meconium aspiration.
在胎粪吸入相关性肺动脉高压仔猪模型中，研究了无创运动通气（NIMV）在脊柱轴诱导产生的周期性加速度（pG(z)）的血流动力学效应。将动物（n = 12）麻醉、麻痹、插管，并通过传统机械通气（CMV）进行支持。气管内滴注胎粪溶液（6 ml/kg）30分钟后，要么继续CMV（n = 6），要么开始NIMV（n = 6）。在吸入后追踪全身和肺血流动力学以及动脉血气变化2小时。相对于CMV对照组，pG(z)组在胎粪吸入后热稀释、心输出量和心率无显著差异。相对于CMV动物，NIMV动物在胎粪吸入后主动脉压和全身血管阻力显著降低（约30%）。与CMV对照组相比，NIMV动物在吸入胎粪后肺动脉压和肺血管阻力也显著降低100%。在CMV和NIMV动物中，胎粪吸入均使总呼吸顺应性显著降低约50%，总呼吸阻力增加约100%，但两组之间的此类改变无差异。CMV和NIMV均能令人满意地支持这些麻痹动物的通气。总之，通过脊柱轴中的pG(z)进行的NIMV降低了胎粪吸入后仔猪的全身和肺血管阻力。
