Hypovolemia and Hypervolemia PDF

11/27/23, 4:28 AM Realizeit for Student Hypovolemia FVD, or hypovolemia, occurs when loss of ECF volume exceeds the intake of fluid. It occurs when water and electrolytes are lost in the same proportion as they exist in normal body fluids; thus, the ratio of serum electrolytes to water remains the...

11/27/23, 4:28 AM Realizeit for Student Hypovolemia FVD, or hypovolemia, occurs when loss of ECF volume exceeds the intake of fluid. It occurs when water and electrolytes are lost in the same proportion as they exist in normal body fluids; thus, the ratio of serum electrolytes to water remains the same. FVD should not be confused with dehydration, which refers to loss of water alone, with increased serum sodium levels. FVD may occur alone or in combination with other imbalances. Serum electrolyte concentrations can remain normal, increase, or increase in FVD (Sterns, 2017a). Pathophysiology FVD results from loss of body fluids and occurs more rapidly when coupled with decreased fluid intake. FVD can also develop with a prolonged period of inadequate intake. Causes of FVD include abnormal fluid losses, such as those resulting from vomiting, diarrhea, GI suctioning, and sweating; decreased intake, as in nausea or lack of access to fluids; and third-space fluid shifts, or the movement of fluid from the vascular system to other body spaces (e.g., with edema formation in burns, ascites with liver dysfunction). Additional causes include diabetes insipidus (a decreased ability to concentrate urine due to either a deficit of ADH or nephron resistance to ADH), adrenal insufficiency, osmotic diuresis, hemorrhage, and coma (Sterns, 2017a). https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=0Dn26kXyU%2f6F5gOCz4%2f2IZsc2gfB3djkaGXwQ9ctgb2A3gz%2bCKrCW4cKwIi8CIqb… 1/2 11/27/23, 4:28 AM Realizeit for Student Hypervolemia Fluid volume excess (FVE), or hypervolemia, refers to an expansion of the ECF caused by the abnormal retention of water and sodium in approximately the same proportions in which they normally exist in the ECF. It is most often secondary to an increase in the total-body sodium content, which, in turn, leads to an increase in total-body water. This can be referred to as an isotonic accumulation of fluids. Because there is isotonic retention of body substances, the serum sodium concentration remains essentially normal. Pathophysiology FVE may be related to simple fluid overload or diminished function of the homeostatic mechanisms responsible for regulating fluid balance. Contributing factors can include heart failure, kidney dysfunction, and cirrhosis of the liver. Another contributing factor is consumption of excessive amounts of table or other sodium salts. Excessive administration of sodiumcontaining fluids in a patient with impaired regulatory mechanisms may predispose them to a serious FVE as well (Sterns, 2018a). https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=0Dn26kXyU%2f6F5gOCz4%2f2IZsc2gfB3djkaGXwQ9ctgb2A3gz%2bCKrCW4cKwIi8CIqb… 2/2