Fluid and Electrolytes

Question 1

Clinical Signs - Daily Weights

Answer 1

(1 kg loss = 1 L fluid loss)

Question 2

Clinical Signs - I & O

Answer 2

Urine output:
- Infants → ≥2 mL/kg/hr
- Children → 0.5-1 mL/kg/hr

Question 3

Clinical Signs - Vital Signs

Answer 3

• Early dehydration: Tachycardia
• Late sign: Hypotension

Question 4

Clinical Signs - Skin & Mucous Membranes

Answer 4

Turgor, dry mucosa, sunken eyes

Question 5

Clinical Signs - Fontanelles

Answer 5

Sunken from dehydration

Question 6

Clinical signs - Cap Refill

Answer 6

• Normal: <2 sec
• Prolonged in dehydration

Question 7

Three Types of Dehydration

Answer 7

Isotonic
Hypotonic
Hypertonic

Question 8

Isotonic Dehydration

Answer 8

• Equal loss of water & sodium → Normal sodium (135-145)
• Most common type
• Causes: Vomiting, diarrhea, hemorrhage
• Risk: Hypovolemic shock

Question 9

Hypotonic Dehydration

Answer 9

• More sodium loss than water loss → Low sodium (<135)
• Fluid shifts from ECF to ICF → Worse ECF depletion
• Causes: Diuretics, excessive water intake, burns

Question 10

Hypertonic Dehydration

Answer 10

• More water loss than sodium loss → High sodium (>145)
• Fluid shifts from ICF to ECF → Cells shrink
• Causes: Diabetes insipidus, excessive sweating, high fever
• Risk: Neurologic complications (seizures, irritability)

Question 11

Mild Dehydration

Answer 11

<5% body loss, Normal vitals, slight thirst, moist mucous membranes, normal UO

Question 12

Moderate Dehydration

Answer 12

6-9% body weight loss, Tachycardia, tachypnea, dry mucous membranes, decreased skin turgor, oliguria, irritable or lethargic

Question 13

Severe Dehydration

Answer 13

> 10% body weight loss, Hypotension, very dry mucous membranes, sunken fontanelle, no tears, minimal/absent UO, lethargy, poor cap refill (>3-4 sec)

Question 14

IV Maintenance Fluids (4-2-1 Rule)

Answer 14

1. First 10 kg → 4 mL/kg/hr
2. Next 10 kg → 2 mL/kg/hr
3. Each kg above 20 kg → 1 mL/kg/hr

Examples:
* 8 kg child → 8 × 4 = 32 mL/hr
* 12 kg child → (10 × 4) + (2 × 2) = 44 mL/hr
* 30 kg child → (10 × 4) + (10 × 2) + (10 × 1) = 70 mL/hr

Question 15

Fluid Management IV bolus (non cardiac/renal)

Answer 15

• Isotonic fluids (Normal Saline or Lactated Ringer’s)
• Bolus dose = 20 mL/kg over 30-60 minutes
• Avoid boluses in cardiac or renal patients

Question 16

Sodium Normal Range / S/S imbalance

Answer 16

135-145 mmol/L

Low (hyponatremia): Confusion, seizures, weakness, nausea

High (hypernatremia): Thirst, irritability, seizures

Question 17

Potassium Normal Range / S/S Imbalance

Answer 17

3.5-5.0 mmol/L

Low (hypokalemia): Weakness, arrhythmias

High (hyperkalemia): Peaked T waves, muscle weakness

Question 18

Calcium Normal Range / S/S Imbalance

Answer 18

8.5-10.5 mg/dL

Low (hypocalcemia): Tetany, seizures

High (hypercalcemia): Weakness, kidney stones

Question 19

Acid Base Balances

Answer 19

Respiratory Acidosis (CO2 retention)

Respiratory Alkalosis (Co2 Loss)

Metabolic Acidosis (Excess Acid)

Metabolic Alkalosis (Loss of Acid)

Question 20

Respiratory Acidosis

Answer 20

(CO₂ Retention)
- Cause: Hypoventilation (asthma, respiratory failure)
- ABG: ↓ pH, ↑ CO₂
- Compensation: Kidneys retain HCO₃

Question 21

Respiratory Alkalosis

Answer 21

(CO₂ Loss)
- Cause: Hyperventilation (anxiety, sepsis, fever)
- ABG: ↑ pH, ↓ CO₂
- Compensation: Kidneys excrete HCO₃

Question 22

Metabolic Alkalosis

Answer 22

(Excess Acid)
- Cause: DKA, diarrhea (bicarbonate loss)
= ABG: ↓ pH, ↓ HCO₃
- Compensation: Lungs hyperventilate (Kussmaul’s breathing)

Question 23

Metabolic Alkalosis

Answer 23

(Loss of Acid)
- Cause: Vomiting, diuretics
- ABG: ↑ pH, ↑ HCO₃
- Compensation: Lungs hypoventilate