FLUIDS AND ELECTROLYTES NURSING
QUESTIONS WITH RATIONALES EXAM
WITH CORRECT QUESTIONS AND
ANSWERS 2025
1) A nurse is caring for a critically ill patient with a urinary retention catheter. Which hourly
urine output should FIRST alert the nurse that the primary health-care provider should be
notified?
1. 20mL
2. 30mL
3. 80mL
4. 120mL - CORRECT-ANSWERSAnswer:
2
Rationale:
The circulating blood volume perfuses the kidneys producing a glomerular filtrate of which
varying amounts are either reabsorbed or excreted to maintain fluid balance. When a person's
hourly urine output is only 30mL, it indicates a deficient circulating fluid volume inadequate
renal perfusion and/or kidney disease. THe primary health-care provider should be notified. The
PCP should be notified long before the hourly urine output reaches 20mL, the hourly output of
60mL is close to the expected range of 30-50mL/hr, and the PCP should not be notified for
120mL because it it indicates adequate kidney perfusion.
2) A nurse is caring for a patient who has dependent edema. Which pressure has caused the
excess fluid in the interstitial compartment?
,1. Oncotic pressure
2. Diffusion pressure
3. Hydrostatic pressure
4. Intraventricular pressure - CORRECT-ANSWERSAnswer:
3
Rationale:
Hydrostatic pressure is the pressure exerted by a fluid within a compartment, such as blood
within the vessels. Hydrostatic pressure moves fluid from an area of greater pressure to an area
of lesser pressure. Hydrostatic pressure within vessels of the body moves fluid from the
intravascular compartment into the interstitial compartment. Interstitial fluid is extracellular fluid
that surrounds cells. Oncotic pressure is the force exerted by colloids that pull or keep fluid
within the intravascular compartment, it is the major force opposing hydrostatic pressure in the
capillaries. Diffusion is a continual intermingling of molecules with movement of molecules
from a solution of higher concentration to lower. Intraventricular pressure is the pressure that
exists in the left and right ventricles of the heart. They do not move fluid.
3) A nurse evaluates a patient's fluid balance by monitoring the patient's intake and output.
Which must the nurse understand about the ratio of the patient's fluid intake and output?
1. Intake should be slightly more than the output
2. Intake should be higher than the fluid output
3. Intake should be lower than the urine output
4. Intake should be equal to the urine output - CORRECT-ANSWERSAnswer:
1
Rationale:
, The volume and composition of body fluids are kept in a delicate balance (total intake is slightly
more than total output) by a harmonious interaction of the kidenys and the endocrine, respiratory,
cardiovascular, integumentary, and gastrointestinal systems. It can't be 2 because if total intake is
higher than output the patient will develop an excess fluid volume. 3 isn't it because if the total
intake is lower than the urine output, the patient will develop a deficient fluid volume. It can't be
4 because if intake and urine output are equal the pt will develop a deficient fluid volume
because of fluid loss through routes other than the kidneys.
4) Hydrochlorothiazide (HCTZ), a diuretic, is prescribed for a patient who is retaining fluid. The
nurse should encourage the patient to ingest nutrients that contain which electrolyte?
1. Magnesium
2. Potassium
3. Calcium
4. Sodium - CORRECT-ANSWERSAnswer:
2
Rationale:
Most diuretics affect the renal mechanisms for tubular secretion and reabsorption of electrolytes,
particularly potassium. Because of potassium's narrow therapetuci window of 3.5-5.0mEq/L and
its role in the sodium-potassium pump and muscle contraction, depleted potassium must be
supplemented by increasing the dietary intake of foods high in potassium and/or the
administration of potassium drug therapy. It isn't 1 because even though loop and thiazide
diuretics enhance magnesium excretion, which may produce mild hypomagnemesia, it does not
require magnesium supplementation. It can't be 3 because serum calcium levels vary depending
on the diuretic, thiazide diuretics such as HCTZ decrease calcium excretion, which may produce
QUESTIONS WITH RATIONALES EXAM
WITH CORRECT QUESTIONS AND
ANSWERS 2025
1) A nurse is caring for a critically ill patient with a urinary retention catheter. Which hourly
urine output should FIRST alert the nurse that the primary health-care provider should be
notified?
1. 20mL
2. 30mL
3. 80mL
4. 120mL - CORRECT-ANSWERSAnswer:
2
Rationale:
The circulating blood volume perfuses the kidneys producing a glomerular filtrate of which
varying amounts are either reabsorbed or excreted to maintain fluid balance. When a person's
hourly urine output is only 30mL, it indicates a deficient circulating fluid volume inadequate
renal perfusion and/or kidney disease. THe primary health-care provider should be notified. The
PCP should be notified long before the hourly urine output reaches 20mL, the hourly output of
60mL is close to the expected range of 30-50mL/hr, and the PCP should not be notified for
120mL because it it indicates adequate kidney perfusion.
2) A nurse is caring for a patient who has dependent edema. Which pressure has caused the
excess fluid in the interstitial compartment?
,1. Oncotic pressure
2. Diffusion pressure
3. Hydrostatic pressure
4. Intraventricular pressure - CORRECT-ANSWERSAnswer:
3
Rationale:
Hydrostatic pressure is the pressure exerted by a fluid within a compartment, such as blood
within the vessels. Hydrostatic pressure moves fluid from an area of greater pressure to an area
of lesser pressure. Hydrostatic pressure within vessels of the body moves fluid from the
intravascular compartment into the interstitial compartment. Interstitial fluid is extracellular fluid
that surrounds cells. Oncotic pressure is the force exerted by colloids that pull or keep fluid
within the intravascular compartment, it is the major force opposing hydrostatic pressure in the
capillaries. Diffusion is a continual intermingling of molecules with movement of molecules
from a solution of higher concentration to lower. Intraventricular pressure is the pressure that
exists in the left and right ventricles of the heart. They do not move fluid.
3) A nurse evaluates a patient's fluid balance by monitoring the patient's intake and output.
Which must the nurse understand about the ratio of the patient's fluid intake and output?
1. Intake should be slightly more than the output
2. Intake should be higher than the fluid output
3. Intake should be lower than the urine output
4. Intake should be equal to the urine output - CORRECT-ANSWERSAnswer:
1
Rationale:
, The volume and composition of body fluids are kept in a delicate balance (total intake is slightly
more than total output) by a harmonious interaction of the kidenys and the endocrine, respiratory,
cardiovascular, integumentary, and gastrointestinal systems. It can't be 2 because if total intake is
higher than output the patient will develop an excess fluid volume. 3 isn't it because if the total
intake is lower than the urine output, the patient will develop a deficient fluid volume. It can't be
4 because if intake and urine output are equal the pt will develop a deficient fluid volume
because of fluid loss through routes other than the kidneys.
4) Hydrochlorothiazide (HCTZ), a diuretic, is prescribed for a patient who is retaining fluid. The
nurse should encourage the patient to ingest nutrients that contain which electrolyte?
1. Magnesium
2. Potassium
3. Calcium
4. Sodium - CORRECT-ANSWERSAnswer:
2
Rationale:
Most diuretics affect the renal mechanisms for tubular secretion and reabsorption of electrolytes,
particularly potassium. Because of potassium's narrow therapetuci window of 3.5-5.0mEq/L and
its role in the sodium-potassium pump and muscle contraction, depleted potassium must be
supplemented by increasing the dietary intake of foods high in potassium and/or the
administration of potassium drug therapy. It isn't 1 because even though loop and thiazide
diuretics enhance magnesium excretion, which may produce mild hypomagnemesia, it does not
require magnesium supplementation. It can't be 3 because serum calcium levels vary depending
on the diuretic, thiazide diuretics such as HCTZ decrease calcium excretion, which may produce
