Question

If an isotonic solution was introduced into the bloodstream, how would this impact?

a) Red blood cell size

b) ECF volume

c) Cardiac Output

d) Mean Arterial Pressure

e) Vasopressin release

Answer 1

Effect of an isotonic solution on the following factors:

a) Red blood cell size - Does not change

b) ECF volume - Increases

c) Cardiac Output - Increases

d) Mean Arterial Pressure - Increases

e) Vasopressin release - Decreases

If the cells are placed in a solution with the same solute concentration as that of the cytoplasm, the solution is said to be “isotonic” and the cell volume remain the same. Introducing an isotonic volume into the systemic circulation increase the extracellular fluid volume. This in turn increase the cardiac output, and mean arterial pressure. The increased ECF volume also increase the renal blood flow, thus, reduce the release of vasopressin.