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HESI Pediatric Fluid & Electrolyte
Exam Bank: IV Therapy, Dehydration,
Acid-Base & Clinical Scenarios Q&A
Table of Contents
Subtopic 1: Pediatric Fluid & Electrolyte Imbalance – Recognition and
Assessment......................................................................................................2
Subtopic 2: Pediatric Intravenous Fluid Therapy – Calculations and
Management..................................................................................................11
Subtopic 3: Electrolyte Imbalances – Clinical Scenarios and Interpretation...20
Subtopic 5: Dehydration Severity and Pediatric Fluid Replacement Strategies
.......................................................................................................................39
Subtopic 6: Pediatric Acid-Base Disturbances – Types, Causes, and
Corrections.....................................................................................................48
Subtopic 7: Fluid and Electrolyte Considerations in Pediatric Surgical and
Trauma Patients.............................................................................................58
Subtopic 8: Pediatric Endocrine Disorders and Fluid-Electrolyte Balance......67
Subtopic 9: Pediatric Gastrointestinal Conditions Impacting Fluid-Electrolyte
Status.............................................................................................................76
Subtopic 10: Fluid and Electrolyte Imbalances in Pediatric Oncology and
Chronic Illness................................................................................................85
, 2
Subtopic 1: Pediatric Fluid & Electrolyte
Imbalance – Recognition and Assessment
Question 1
A 6-month-old infant is admitted with vomiting and diarrhea. Which clinical
sign is the most reliable indicator of moderate dehydration in this age group?
A. Sunken anterior fontanel
B. Capillary refill time greater than 2 seconds
C. Moist mucous membranes
D. Presence of tears when crying
Correct Answer: B. Capillary refill time greater than 2 seconds
Rationale: Capillary refill time >2 seconds is a sensitive and early indicator of
reduced perfusion and moderate dehydration. Fontanel changes are less
specific, and tears may still be present in moderate dehydration.
Question 2
A toddler with gastroenteritis is receiving oral rehydration therapy (ORT).
Which solution is most appropriate?
A. Apple juice
B. Chicken broth
C. Tap water
D. Commercial oral rehydration solution (ORS)
Correct Answer: D. Commercial oral rehydration solution (ORS)
, 3
Rationale: ORS contains the correct balance of glucose and electrolytes to
promote absorption and rehydration. Juice, broth, and water lack proper
electrolyte concentrations and may worsen imbalances.
Question 3
Which electrolyte imbalance is most associated with prolonged vomiting in
infants?
A. Hyperkalemia
B. Hypokalemia
C. Hypernatremia
D. Hypocalcemia
Correct Answer: B. Hypokalemia
Rationale: Vomiting leads to loss of potassium-rich gastric secretions,
increasing the risk of hypokalemia.
Question 4
A school-age child has a sodium level of 125 mEq/L. Which symptom is most
concerning?
A. Nausea
B. Thirst
C. Muscle cramps
D. Seizures
Correct Answer: D. Seizures
Rationale: Severe hyponatremia can lead to cerebral edema and seizures
due to altered neuronal activity.
, 4
Question 5
Which of the following findings suggests hyperkalemia in a child?
A. Peaked T waves on ECG
B. Bradycardia with flattened T waves
C. U waves on ECG
D. Normal ECG with mild tachycardia
Correct Answer: A. Peaked T waves on ECG
Rationale: Peaked T waves are a hallmark sign of hyperkalemia and indicate
potential cardiac instability.
Question 6
An infant with dehydration weighs 6.5 kg. What is the minimum daily fluid
requirement using the Holliday-Segar method?
A. 350 mL/day
B. 650 mL/day
C. 1000 mL/day
D. 1200 mL/day
Correct Answer: B. 650 mL/day
Rationale: The Holliday-Segar method calculates 100 mL/kg/day for the first
10 kg, so 6.5 kg × 100 = 650 mL/day.
Question 7
HESI Pediatric Fluid & Electrolyte
Exam Bank: IV Therapy, Dehydration,
Acid-Base & Clinical Scenarios Q&A
Table of Contents
Subtopic 1: Pediatric Fluid & Electrolyte Imbalance – Recognition and
Assessment......................................................................................................2
Subtopic 2: Pediatric Intravenous Fluid Therapy – Calculations and
Management..................................................................................................11
Subtopic 3: Electrolyte Imbalances – Clinical Scenarios and Interpretation...20
Subtopic 5: Dehydration Severity and Pediatric Fluid Replacement Strategies
.......................................................................................................................39
Subtopic 6: Pediatric Acid-Base Disturbances – Types, Causes, and
Corrections.....................................................................................................48
Subtopic 7: Fluid and Electrolyte Considerations in Pediatric Surgical and
Trauma Patients.............................................................................................58
Subtopic 8: Pediatric Endocrine Disorders and Fluid-Electrolyte Balance......67
Subtopic 9: Pediatric Gastrointestinal Conditions Impacting Fluid-Electrolyte
Status.............................................................................................................76
Subtopic 10: Fluid and Electrolyte Imbalances in Pediatric Oncology and
Chronic Illness................................................................................................85
, 2
Subtopic 1: Pediatric Fluid & Electrolyte
Imbalance – Recognition and Assessment
Question 1
A 6-month-old infant is admitted with vomiting and diarrhea. Which clinical
sign is the most reliable indicator of moderate dehydration in this age group?
A. Sunken anterior fontanel
B. Capillary refill time greater than 2 seconds
C. Moist mucous membranes
D. Presence of tears when crying
Correct Answer: B. Capillary refill time greater than 2 seconds
Rationale: Capillary refill time >2 seconds is a sensitive and early indicator of
reduced perfusion and moderate dehydration. Fontanel changes are less
specific, and tears may still be present in moderate dehydration.
Question 2
A toddler with gastroenteritis is receiving oral rehydration therapy (ORT).
Which solution is most appropriate?
A. Apple juice
B. Chicken broth
C. Tap water
D. Commercial oral rehydration solution (ORS)
Correct Answer: D. Commercial oral rehydration solution (ORS)
, 3
Rationale: ORS contains the correct balance of glucose and electrolytes to
promote absorption and rehydration. Juice, broth, and water lack proper
electrolyte concentrations and may worsen imbalances.
Question 3
Which electrolyte imbalance is most associated with prolonged vomiting in
infants?
A. Hyperkalemia
B. Hypokalemia
C. Hypernatremia
D. Hypocalcemia
Correct Answer: B. Hypokalemia
Rationale: Vomiting leads to loss of potassium-rich gastric secretions,
increasing the risk of hypokalemia.
Question 4
A school-age child has a sodium level of 125 mEq/L. Which symptom is most
concerning?
A. Nausea
B. Thirst
C. Muscle cramps
D. Seizures
Correct Answer: D. Seizures
Rationale: Severe hyponatremia can lead to cerebral edema and seizures
due to altered neuronal activity.
, 4
Question 5
Which of the following findings suggests hyperkalemia in a child?
A. Peaked T waves on ECG
B. Bradycardia with flattened T waves
C. U waves on ECG
D. Normal ECG with mild tachycardia
Correct Answer: A. Peaked T waves on ECG
Rationale: Peaked T waves are a hallmark sign of hyperkalemia and indicate
potential cardiac instability.
Question 6
An infant with dehydration weighs 6.5 kg. What is the minimum daily fluid
requirement using the Holliday-Segar method?
A. 350 mL/day
B. 650 mL/day
C. 1000 mL/day
D. 1200 mL/day
Correct Answer: B. 650 mL/day
Rationale: The Holliday-Segar method calculates 100 mL/kg/day for the first
10 kg, so 6.5 kg × 100 = 650 mL/day.
Question 7
