HESI Pediatric GI Disorders
Examination (Latest 2026)|| Questions
And Answers With Rationales/Graded
A+/2026 Update/100% Correct
/Instant Download
Section 1: Fluid & Electrolyte Management in GI Illness (Questions 1–15)
1. A 4-month-old with severe gastroenteritis has sunken fontanelles, dry
mucous membranes, and no urine output for 8 hours. Which intervention has
the highest priority?
A. Oral rehydration solution (ORS) 5 mL every 5 minutes
B. Blood transfusion
C. IV bolus of 20 mL/kg isotonic fluid
D. Antiemetic suppository
Rationale: Severe dehydration with shock requires rapid IV isotonic fluid
resuscitation (20 mL/kg lactated Ringer’s or NS), per 2026 AAP guidelines. ORS
is for mild-moderate dehydration.
2. Which IV fluid is contraindicated as a bolus in pediatric dehydration?
A. Lactated Ringer’s
B. D5W
C. Normal saline
D. Plasmalyte
Rationale: D5W is hypotonic and can cause cerebral edema; never use for volume
resuscitation.
3. A 2-year-old with rotavirus has isotonic dehydration. After a 20 mL/kg
bolus, he remains lethargic. Next step?
A. Repeat 20 mL/kg bolus
B. Start maintenance IV D5 0.45% NS
C. Administer second bolus and reassess
D. Check serum sodium
,Rationale: Persistent signs of shock warrant a second 20 mL/kg bolus; up to 60
mL/kg may be needed.
4. Which serum sodium level indicates hypernatremic dehydration?
A. 130 mEq/L
B. 155 mEq/L
C. 138 mEq/L
D. 120 mEq/L
Rationale: Hypernatremia = Na >150 mEq/L; rehydrate slowly over 48 hours to
avoid cerebral edema.
5. A 6-month-old has hyponatremic dehydration (Na 125 mEq/L). Which
initial fluid is safest?
A. 0.9% saline
B. 0.9% saline + potassium when urinating
C. 3% saline
D. D5 0.45% saline
Rationale: Correct hypovolemia with isotonic fluids first; add K+ after urine
output confirmed.
6. What is the recommended oral rehydration solution (ORS) osmolality per
WHO 2026?
A. 245 mOsm/L
B. 245–310 mOsm/L
C. 400 mOsm/L
D. 150 mOsm/L
Rationale: Low-osmolarity ORS (245 mOsm/L) reduces stool output and
vomiting.
7. A toddler is vomiting but tolerates ORS. Best initial ORS volume post-
emesis?
A. 50 mL/kg over 4 hours
B. 5–10 mL every 5 minutes
C. 100 mL/kg bolus
D. Avoid ORS for 24 hours
Rationale: Frequent small volumes reduce vomiting; increase gradually as
tolerated.
, 8. Which lab finding in a dehydrated child indicates prerenal acute kidney
injury?
A. BUN/Cr >20
B. Fractional excretion of sodium <1%
C. Urine sodium >40 mEq/L
D. Hematuria
Rationale: FeNa <1% indicates prerenal cause (dehydration); >2% suggests
intrinsic renal injury.
9. A 9-month-old with diarrhea develops ileus and abdominal distension.
Serum K+ is 2.8 mEq/L. Which ECG finding is most likely?
A. Peaked T waves
B. U waves
C. Wide QRS
D. Short QT
Rationale: Hypokalemia causes U waves, flat T waves; life-threatening.
10. Maximum safe IV potassium infusion rate in pediatric patient?
A. 0.1 mEq/kg/hr
B. 0.5 mEq/kg/hr
C. 1 mEq/kg/hr
D. 2 mEq/kg/hr
Rationale: Max 0.5 mEq/kg/hr; central line may allow 1 mEq/kg/hr with cardiac
monitoring.
11. A 5-year-old with gastroenteritis has urine output 0.8 mL/kg/hr.
Interpretation?
A. Severe dehydration
B. Adequate output
C. Overhydration
D. Oliguric renal failure
Rationale: Normal urine output in child >1 year is 0.5–1 mL/kg/hr.
12. Which sign is most specific for moderate dehydration in an infant?
A. Tachycardia
B. Prolonged capillary refill >2 seconds
Examination (Latest 2026)|| Questions
And Answers With Rationales/Graded
A+/2026 Update/100% Correct
/Instant Download
Section 1: Fluid & Electrolyte Management in GI Illness (Questions 1–15)
1. A 4-month-old with severe gastroenteritis has sunken fontanelles, dry
mucous membranes, and no urine output for 8 hours. Which intervention has
the highest priority?
A. Oral rehydration solution (ORS) 5 mL every 5 minutes
B. Blood transfusion
C. IV bolus of 20 mL/kg isotonic fluid
D. Antiemetic suppository
Rationale: Severe dehydration with shock requires rapid IV isotonic fluid
resuscitation (20 mL/kg lactated Ringer’s or NS), per 2026 AAP guidelines. ORS
is for mild-moderate dehydration.
2. Which IV fluid is contraindicated as a bolus in pediatric dehydration?
A. Lactated Ringer’s
B. D5W
C. Normal saline
D. Plasmalyte
Rationale: D5W is hypotonic and can cause cerebral edema; never use for volume
resuscitation.
3. A 2-year-old with rotavirus has isotonic dehydration. After a 20 mL/kg
bolus, he remains lethargic. Next step?
A. Repeat 20 mL/kg bolus
B. Start maintenance IV D5 0.45% NS
C. Administer second bolus and reassess
D. Check serum sodium
,Rationale: Persistent signs of shock warrant a second 20 mL/kg bolus; up to 60
mL/kg may be needed.
4. Which serum sodium level indicates hypernatremic dehydration?
A. 130 mEq/L
B. 155 mEq/L
C. 138 mEq/L
D. 120 mEq/L
Rationale: Hypernatremia = Na >150 mEq/L; rehydrate slowly over 48 hours to
avoid cerebral edema.
5. A 6-month-old has hyponatremic dehydration (Na 125 mEq/L). Which
initial fluid is safest?
A. 0.9% saline
B. 0.9% saline + potassium when urinating
C. 3% saline
D. D5 0.45% saline
Rationale: Correct hypovolemia with isotonic fluids first; add K+ after urine
output confirmed.
6. What is the recommended oral rehydration solution (ORS) osmolality per
WHO 2026?
A. 245 mOsm/L
B. 245–310 mOsm/L
C. 400 mOsm/L
D. 150 mOsm/L
Rationale: Low-osmolarity ORS (245 mOsm/L) reduces stool output and
vomiting.
7. A toddler is vomiting but tolerates ORS. Best initial ORS volume post-
emesis?
A. 50 mL/kg over 4 hours
B. 5–10 mL every 5 minutes
C. 100 mL/kg bolus
D. Avoid ORS for 24 hours
Rationale: Frequent small volumes reduce vomiting; increase gradually as
tolerated.
, 8. Which lab finding in a dehydrated child indicates prerenal acute kidney
injury?
A. BUN/Cr >20
B. Fractional excretion of sodium <1%
C. Urine sodium >40 mEq/L
D. Hematuria
Rationale: FeNa <1% indicates prerenal cause (dehydration); >2% suggests
intrinsic renal injury.
9. A 9-month-old with diarrhea develops ileus and abdominal distension.
Serum K+ is 2.8 mEq/L. Which ECG finding is most likely?
A. Peaked T waves
B. U waves
C. Wide QRS
D. Short QT
Rationale: Hypokalemia causes U waves, flat T waves; life-threatening.
10. Maximum safe IV potassium infusion rate in pediatric patient?
A. 0.1 mEq/kg/hr
B. 0.5 mEq/kg/hr
C. 1 mEq/kg/hr
D. 2 mEq/kg/hr
Rationale: Max 0.5 mEq/kg/hr; central line may allow 1 mEq/kg/hr with cardiac
monitoring.
11. A 5-year-old with gastroenteritis has urine output 0.8 mL/kg/hr.
Interpretation?
A. Severe dehydration
B. Adequate output
C. Overhydration
D. Oliguric renal failure
Rationale: Normal urine output in child >1 year is 0.5–1 mL/kg/hr.
12. Which sign is most specific for moderate dehydration in an infant?
A. Tachycardia
B. Prolonged capillary refill >2 seconds
