Is there a limit for volume removal in Hypervolemia?
Diuretics cause fluid loss from the vascular space. This contraction of the vascular space leads to a fall in venous pressure and in capillary hydraulic pressure. The fall in capillary hydraulic pressure promotes movement of edema fluid from the interstitial space into the vascular space. The rate at which replenishment of the vascular space occurs varies. Overly rapid diuresis leads to a significant reduction in the vascular space, which will in turn lead to decreased venous return to the heart, decreased cardiac filling pressures, decreased stroke volume, decreased cardiac output, and ultimately hypotension. Impaired kidney perfusion may lead to prerenal azotemia. Most patients, however, can tolerate gradual correction of volume overload. In patients with substantial peripheral edema, edema fluid can be mobilized from most capillary beds. As a result, a negative fluid balance of 2 to 3 L/day can generally be accomplished without significant reduction in vascular volume.
