van Lieshout J J, ten Harkel A D, van Leeuwen A M, Wieling W
Department of Medicine, University of Amsterdam, The Netherlands.
Neth J Med. 1991 Aug;39(1-2):72-83.
We studied the effects of acute and chronic volume expansion on orthostatic blood pressure control in a 22-year-old female with hypoadrenergic orthostatic hypotension. Acute volume expansion on two occasions had unexpected effects: a decrease respectively no change in orthostatic tolerance and no change in upright blood pressure immediately after volume expansion followed by a marked improvement 8 h thereafter. The time course of changes in haematocrit and serum protein indicated an initial extravasation of plasma followed by a subsequent larger fluid shift back to the intravascular space. These effects had vanished after 3 days. Chronic volume expansion by head-up tilt at night and fludrocortisone resulted in a marked improvement in orthostatic blood pressure control at a comparable increment in body weight and sodium balance for the next 7 years until now. The circadian circulatory variation with orthostatic blood pressure lowest in the morning remained present after chronic volume expansion. We conclude in this patient that the effects of acute volume expansion on orthostatic blood pressure in autonomic failure are complex and not predictive for the beneficial effects of chronic volume expansion.
我们研究了急性和慢性容量扩张对一名患有低肾上腺素能性直立性低血压的22岁女性直立性血压控制的影响。两次急性容量扩张产生了意想不到的效果：容量扩张后立即出现直立耐受性分别降低和无变化，以及直立血压无变化，随后8小时后有显著改善。血细胞比容和血清蛋白的变化时间过程表明，最初血浆外渗，随后有更大的液体转移回到血管内空间。这些效果在3天后消失。通过夜间头高位倾斜和氟氢可的松进行慢性容量扩张，在接下来的7年直至现在，在体重和钠平衡有相当增量的情况下，直立性血压控制有显著改善。慢性容量扩张后，早晨直立性血压最低的昼夜循环变化仍然存在。我们得出结论，在该患者中，急性容量扩张对自主神经功能衰竭时直立性血压的影响是复杂的，且不能预测慢性容量扩张的有益效果。
