Pathophysiology Concepts Test 3 Study Guide Updated 2025
Compartmental distribution of body fluids
The distribution of body fluids into intracellular fluid (40% body weight) and extracellular
fluid (20% body weight).
Intracellular fluid
Contains two-thirds of body water and is abundant in potassium.
Extracellular fluid
Contains the remaining third of body water, abundant in sodium and chloride, and includes
interstitial fluid and plasma.
Plasma
1/4 of extracellular fluid.
Interstitial fluid
3/4 of extracellular fluid.
Transcellular fluid
1% of extracellular fluid.
Third spacing
When too much fluid moves from the intracellular fluid to the interstitial space.
Cations
Positively charged ions such as Na+, Ca2+, K+.
, Pathophysiology Concepts Test 3 Study Guide Updated 2025
Anions
Negatively charged ions such as Cl-, HCO3-.
Sodium Balance
The kidney is the main regulator of Na+, which is the most abundant cation in the body with a
normal plasma range of 135-145 mEq/L.
Potassium
The second most abundant cation in the body and the major intracellular fluid cation with a
normal plasma range of 3.5-5 mEq/L.
Calcium
A major divalent cation in the body with a normal plasma range of 8.5-10.5 mg/dL.
Hypoparathyroidism manifestations
Includes hypocalcemia, hyperphosphatemia, hair dryness, nail ridges, skin dryness, bone loss,
tingling in extremities, visual changes, muscle cramps, seizures, fatigue, tetany, and bone
pain.
Ascites
A condition in which fluid collects in spaces within your abdomen.
Management of Ascites
Cut back on the amount of fluids you drink and stop drinking alcohol.
Dehydration
Compartmental distribution of body fluids
The distribution of body fluids into intracellular fluid (40% body weight) and extracellular
fluid (20% body weight).
Intracellular fluid
Contains two-thirds of body water and is abundant in potassium.
Extracellular fluid
Contains the remaining third of body water, abundant in sodium and chloride, and includes
interstitial fluid and plasma.
Plasma
1/4 of extracellular fluid.
Interstitial fluid
3/4 of extracellular fluid.
Transcellular fluid
1% of extracellular fluid.
Third spacing
When too much fluid moves from the intracellular fluid to the interstitial space.
Cations
Positively charged ions such as Na+, Ca2+, K+.
, Pathophysiology Concepts Test 3 Study Guide Updated 2025
Anions
Negatively charged ions such as Cl-, HCO3-.
Sodium Balance
The kidney is the main regulator of Na+, which is the most abundant cation in the body with a
normal plasma range of 135-145 mEq/L.
Potassium
The second most abundant cation in the body and the major intracellular fluid cation with a
normal plasma range of 3.5-5 mEq/L.
Calcium
A major divalent cation in the body with a normal plasma range of 8.5-10.5 mg/dL.
Hypoparathyroidism manifestations
Includes hypocalcemia, hyperphosphatemia, hair dryness, nail ridges, skin dryness, bone loss,
tingling in extremities, visual changes, muscle cramps, seizures, fatigue, tetany, and bone
pain.
Ascites
A condition in which fluid collects in spaces within your abdomen.
Management of Ascites
Cut back on the amount of fluids you drink and stop drinking alcohol.
Dehydration
