Hoon R S, Balasubramanian V, Mathew O P, Tiwari S C, Sharma S C, Chadha K S
J Appl Physiol Respir Environ Exerc Physiol. 1977 May;42(5):722-7. doi: 10.1152/jappl.1977.42.5.722.
Resting stroke volume and cardiac output of 50 normal healthy sea-level residents (group A) were estimated by the noninvasive technique of electrical impedance plethysmography. They were then airlifted to an altitude of 3,658 m and serial estimations carried out at 0-4 h and 5-8 h and on the 2nd, 3rd, 4th, 5th, and 10th days. The subjects were brought back to sea level and studied for up to 5 days. Thirty permanent residents of high altitude (group B) and sixteen lowlanders temporarily resident at high altitude (group C) were also subjected to similar studies. It was found that resting stroke volume and cardiac output of group A started falling immediately on arrival at high altitude, reached the minimum on the 3rd day and tended to improved on the 4th and 5th day, but showed a secondary fall on the 10th day. The reduction in stroke volume in this group was not fully compensated by tachycardia. On return to sea level the cardiac output normalized immediately, the stroke volume on the 2nd day. At sea level goup A had values similar to group B and at high altitude to group C.
通过无创电阻抗体积描记技术估算了50名正常健康的海平面居民（A组）的静息每搏输出量和心输出量。然后将他们空运到海拔3658米处，并在0 - 4小时、5 - 8小时以及第2、3、4、5和10天进行系列估算。受试者被带回海平面并进行长达5天的研究。30名高海拔常住居民（B组）和16名临时居住在高海拔地区的低地居民（C组）也接受了类似研究。结果发现，A组的静息每搏输出量和心输出量在抵达高海拔地区后立即开始下降，在第3天达到最低值，在第4天和第5天趋于改善，但在第10天出现二次下降。该组每搏输出量的减少未被心动过速完全代偿。回到海平面后，心输出量立即恢复正常，每搏输出量在第2天恢复正常。在海平面时，A组的值与B组相似，在高海拔时与C组相似。
