Chapter 18: Fluid & Electrolyte Lecture Review

Question 1

How do we assess fluid status in children?

Answer 1

Daily weights (1 kg = 1 L fluid), strict intake & output (I&O), including diapers and linens, urine output, physical exam findings (skin turgor, mucous membranes), and vital signs.

Question 2

What is the normal urine output for infants?

Answer 2

2 mL/kg/hr

Question 3

What is the normal urine output for children?

Answer 3

0.5–1 mL/kg/hr

Question 4

What are the main causes of dehydration in children?

Answer 4

Diarrhea, vomiting, gastroenteritis, febrile illness, stomatitis, pharyngitis, burns, DKA, diabetes insipidus.

Question 5

What are the three types of dehydration?

Answer 5

Isotonic: Equal loss of sodium and water; normal serum sodium.
Hypotonic: More sodium loss than water; serum sodium is low; fluid shifts to ICF.
Hypertonic: More water loss than sodium; serum sodium is high; fluid shifts to ECF—s/s appear later.

Question 6

What are signs and % of body weight loss for mild dehydration?

Answer 6

Up to 5% body weight loss: Alert, normal/slightly ↓ urine, moist mucosa.

Question 7

What are signs and % of body weight loss for moderate dehydration?

Answer 7

6–9% body weight loss: Sleepy/lethargic, ↓ turgor, ↓ output, dark urine, dry mucosa.

Question 8

What are signs and % of body weight loss for severe dehydration?

Answer 8

≥10% body weight loss: Irritability or non-responsiveness, tachycardia, tachypnea, ↓/absent urine.

Question 9

What is the IV bolus amount for children (without cardiac/renal issues)?

Answer 9

20 mL/kg of isotonic fluid (NS or LR) over 30–60 minutes.

Question 10

What is the 4-2-1 Rule for maintenance IV fluids?

Answer 10

First 10 kg: 4 mL/kg/hr
Next 10 kg (10–20 kg): 2 mL/kg/hr
Every kg >20 kg: 1 mL/kg/hr
Example (30 kg): 40 + 20 + 10 = 70 mL/hr

Question 11

Why should you be cautious with IV fluid boluses in some patients?

Answer 11

Children with cardiac or renal conditions are at higher risk for fluid overload.

Question 12

What are normal pediatric electrolyte values for sodium?

Answer 12

135–145 mmol/L

Question 13

What are normal pediatric electrolyte values for potassium?

Answer 13

3.5–5 mmol/L

Question 14

What are normal pediatric electrolyte values for calcium?

Answer 14

2.8–2.86 mmol/L

Question 15

What are normal pediatric electrolyte values for magnesium?

Answer 15

1.6–2.4 mg/dL

Question 16

What are the four types of acid-base imbalances?

Answer 16

Respiratory Acidosis: CO₂ retention (e.g., asthma, respiratory failure) - ↑ RR and depth (if able).
Respiratory Alkalosis: Hyperventilation, fever, anxiety, sepsis - ↓ RR and depth.
Metabolic Acidosis: DKA, diarrhea (HCO₃ loss) - ↑ RR and depth (Kussmaul breathing).
Metabolic Alkalosis: Vomiting, excess HCO₃ - ↓ RR and depth.