Chapter 8- Disorders of Fluid, Electrolyte, and Acid-Base Balance Test Bank/ NURS 3365

1. A client develops interstitial edema as a result of decreased: A) Vascular volume B) Hydrostatic pressure C) Capillary permeability D) Colloidal osmotic pressure Ans: D Feedback: Edema can be defined as palpable swelling produced by an increased interstitial fluid volume. The physiologic mechanisms that contribute to edema formation include factors that (1) increase capillary filtration (hydrostatic) pressure, (2) decrease the capillary colloid osmotic pressure, (3) increase capillary permeability, or (4) produce obstruction to lymph flow. 2. A client has been receiving intravenous normal saline at a rate of 125 mL/hour since her surgery 2 days earlier. As a result, she has developed an increase in vascular volume and edema. Which of the following phenomena accounts for this client's edema? A) Obstruction of lymph flow B) Increased capillary permeability C) Decreased capillary colloidal osmotic pressure D) Increased capillary filtration pressure Ans: D Feedback: An increase in vascular volume results in an increase in capillary filtration pressure. Consequently, movement of vascular fluid into the interstitial spaces increases and edema ensues. An increase in vascular volume does not directly result in obstruction of lymph flow, increased capillary permeability, or decreased capillary colloidal osmotic pressure. 3. The most reliable method for measuring body water or fluid volume increase is by assessing: A) Tissue turgor B) Intake and output C) Body weight change D) Serum sodium levels Ans: C Feedback: Daily weights are a reliable index of water volume gain (1 L of water weighs 2.2 pounds). Daily weight measurements taken at the same time each day with the same amount of clothing provide a useful index of water gain due to edema. When an unbalanced distribution of body water exists in the tissues and organs, assessment of surface skin tissue turgor will be inaccurate. Measurement of renal output is unreliable because fluid retention may be a compensatory response, or the renal system may be dysfunctional. Serum sodium levels are affected by multiple variables other than body water volume. 4. A client with a diagnosis of liver cirrhosis secondary to alcohol abuse has a distended abdomen as a result of fluid accumulation in his peritoneal cavity (ascites). Which of the following pathophysiologic processes contributes to this third spacing? A) Abnormal increase in transcellular fluid volume B) Increased capillary colloidal osmotic pressure C) Polydipsia D) Impaired hormonal control of fluid volume Ans: A Feedback: Third spacing represents the loss or trapping of extracellular fluid (ECF) in the transcellular space and a consequent increase in transcellular fluid volume. The serous cavities are part of the transcellular compartment located in strategic body areas where there is continual movement of body structures—the pericardial sac, the peritoneal cavity, and the pleural cavity. Polydipsia and increased fluid intake alone are insufficient to cause third spacing, and increased capillary colloidal osmotic pressure would result in increased intracellular fluid (ICF). The etiology of third spacing does not normally include alterations in hormonal control of fluid balance.