The kidneys control plasma volume by controlling how much water a person excretes.

肾脏通过控制一个人排出多少水来控制血浆量。

In time, plasma volume expands so much that fluid in blood vessels is more likely to get pushed into tissues and across tissues into large open spaces, like the peritoneal cavity.

一段时间后，血容量会扩大很多；血管内的液体更可能会被挤压进组织里，并且会通过组织进入大的开放性空间，比如腹膜腔。

The plasma volume has a direct effect on the total blood volume, which has a direct effect on your blood pressure.

血浆量对总血容量有直接影响，而总血容量对血压有直接影响。