Albelda S M, Hansen-Flaschen J H, Lanken P N, Fishman A P
J Appl Physiol (1985). 1986 Jun;60(6):2063-70. doi: 10.1152/jappl.1986.60.6.2063.
To determine the effect of an increase in spontaneous minute ventilation on lung fluid balance, we added external dead space to the breathing circuit of six tracheostomized, unanesthetized, spontaneously breathing sheep in which lung lymph fistulas had been created surgically. The addition of 120-180 ml of dead space caused minute ventilation to increase by 50-100% (secondary to increases in both tidal volume and frequency), without changing pulmonary arterial pressure, pulmonary capillary wedge pressure, cardiac output, or arterial blood gas tensions. The increase in spontaneous ventilation was associated with an average increase of 27% in lung lymph flow (P less than 0.05) and an average reduction of 11% in the lymph-to-plasma concentration ratio (L/P) for total protein (P less than 0.05). Lymph flow and L/P for total protein approached stable values after 2-3 h of hyperpnea, and the increase in lymph flow persisted for at least 18 h of dead-space breathing. Removal of dead space was associated with a rapid return (within 45 min) of lymph flow to base-line levels. These results suggest that hyperpnea increases the pulmonary transvascular filtration rate. Since no changes in vascular pressures or cardiac output were observed, this increase in transvascular filtration is most likely due to a fall in interstitial fluid pressure.
为了确定自主分钟通气量增加对肺液体平衡的影响，我们在六只已行气管造口术、未麻醉、自主呼吸的绵羊的呼吸回路中增加了外部死腔，这些绵羊已通过手术建立了肺淋巴瘘。增加120 - 180毫升死腔导致分钟通气量增加50 - 100%（继发于潮气量和频率的增加），而肺动脉压、肺毛细血管楔压、心输出量或动脉血气张力均无变化。自主通气增加与肺淋巴流量平均增加27%相关（P<0.05），总蛋白的淋巴与血浆浓度比（L/P）平均降低11%（P<0.05）。在通气过度2 - 3小时后，总蛋白的淋巴流量和L/P接近稳定值，淋巴流量的增加在死腔呼吸至少18小时内持续存在。去除死腔后，淋巴流量在45分钟内迅速恢复到基线水平。这些结果表明，通气过度会增加肺血管外滤过率。由于未观察到血管压力或心输出量的变化，这种血管外滤过的增加很可能是由于间质液压力下降所致。
