NUR256 Chapter 10

For exam 2

Osmosis

Water moves from low solute to high solute concentration. Think: fluid shifting into swollen cells.

Diffusion

Solutes move from high to low concentration. No energy needed.

Filtration

Movement of water + small solutes under pressure (like in kidneys).

Active Transport

Requires ATP. Moves substances against the gradient (e.g., Na⁺/K⁺ pump in cells).

Kidneys

Filter blood, excrete waste, regulate electrolytes, and activate RAAS to retain sodium + water.

Lungs

Exhale water vapor + regulate acid-base balance by controlling CO₂.

ADH (antidiuretic hormone)

Keeps water in

Aldosterone

Saves sodium (and water), loses potassium.

ANP/BNP

Causes sodium/water loss when fluid volume is too high.

Fluid Volume Deficit (FVD)

→ Causes: Vomiting, diarrhea, burns, hemorrhage.
→ Signs: ↓BP, ↑HR, dry mucosa, ↓urine output, weight loss.
→ Interventions: Give fluids, monitor I&O, daily weight, safety for dizziness.

Fluid Volume Excess (FVE)

→ Causes: HF, renal failure, too much IV fluid.
→ Signs: Edema, crackles, weight gain, JVD, ↑BP.
→ Interventions: Diuretics, restrict fluids/Na⁺, elevate HOB, daily weight.

Sodium (Na⁺)

135-145 mEq/L

Hyponatremia (sodium deficit)

→ Causes: GI losses, SIADH, excess water.
→ Signs: Confusion, seizures, weakness.
→ Nursing Care: Fluid restriction, seizure precautions, give hypertonic saline if severe.

Hypernatremia (sodium excess)

→ Causes: Dehydration, diabetes insipidus, salt overload.
→ Signs: Thirst, dry mouth, restlessness, seizures.
→ Nursing Care: Oral fluids, hypotonic IV fluids, neuro monitoring.

Potassium (K)

3.5-5 mEq/L

Hypokalemia

→ Causes: Diuretics, vomiting, insulin, alkalosis.
→ Signs: Weakness, ↓DTRs, flat T waves, cramps.
→ Nursing Care: Give K⁺ (oral or IV pump only), monitor ECG, teach high-K⁺ foods.

Hyperkalemia

→ Causes: Renal failure, trauma, ACE inhibitors, acidosis.
→ Signs: Peaked T waves, muscle weakness, paresthesia.
→ Nursing Care: Calcium gluconate, insulin + D50, Kayexalate, monitor ECG.

Calcium (Ca)

8.5-10.5 mg/dL

Hypocalcemia

→ Causes: Hypoparathyroid, pancreatitis, low Vit D.
→ Signs: Chvostek's, Trousseau's, tetany, numbness.
→ Nursing Care: IV/PO calcium, seizure precautions, airway monitoring.

Hypercalcemia

→ Causes: Hyperparathyroidism, bone cancer, thiazides.
→ Signs: Lethargy, ↓DTRs, kidney stones, constipation.
→ Nursing Care: Hydration, loop diuretics, mobility, monitor ECG.

Magnesium (Mg)

1.5-2.5 mg/dL

Hypomagnesemia

→ Causes: Alcoholism, diarrhea, diuretics.
→ Signs: ↑ reflexes, tremors, seizures, torsades.
→ Nursing Care: IV Mg sulfate slow, seizure watch, ECG monitor.

Hypermagnesemia

→ Causes: Renal failure, too much Mg meds.
→ Signs: ↓ reflexes, hypotension, bradycardia, lethargy.
→ Nursing Care: Stop Mg, give IV calcium, support airway.

Phosphorus (P)

2.5-4.5 mg/dL

Hypophosphatemia

→ Causes: Refeeding, alcohol abuse.
→ Signs: Weakness, ↓CO, confusion.
→ Nursing Care: PO or IV phosphate, monitor heart.

Hyperphosphatemia

→ Causes: Renal failure, tumor lysis.
→ Signs: Symptoms of low calcium (tetany).
→ Nursing Care: Phosphate binders, dietary restrictions.

Chloride

98-106 mEq/L

Hypochloremia

→ Causes: Vomiting, suctioning, burns.
→ Signs: Tetany, slow/shallow breathing.
→ Nursing Care: NS IV fluids, increase salt intake.

Hyperchloremia

→ Causes: Dehydration, too much NS, kidney issues.
→ Signs: Kussmaul respirations, weakness.
→ Nursing Care: Fix cause, hydrate, give bicarbonate if needed.

Respiratory Acidosis

🫁 Cause: Lungs aren’t getting rid of CO₂ (hypoventilation)
🧠 Common causes: COPD, pneumonia, drug overdose, airway obstruction
📊 ABG:

• ↓ pH

• ↑ PaCO₂

👩‍⚕ Nursing Actions:

• Improve breathing: oxygen, suction, bronchodilators

• Support ventilation (may need BiPAP or intubation)

Respiratory Alkalosis

🫁 Cause: Lungs are blowing off too much CO₂ (hyperventilation)
🧠 Common causes: Anxiety, pain, fever, PE
📊 ABG:

• ↑ pH

• ↓ PaCO₂

👩‍⚕ Nursing Actions:

• Calm the patient

• Slow breathing (breathing into hands or paper bag)

• Treat pain or anxiety

Metabolic Acidosis

💉 Cause: Too much acid or loss of bicarb
🧠 Common causes: DKA, kidney failure, diarrhea
📊 ABG:

• ↓ pH

• ↓ HCO₃⁻

👩‍⚕ Nursing Actions:

• Treat the cause (insulin for DKA, fluids for diarrhea)

• Monitor potassium (often ↑ in acidosis)

• Give bicarbonate if severe

Metabolic Alkalosis

💉 Cause: Too much bicarb or loss of acid
🧠 Common causes: Vomiting, NG suction, diuretics
📊 ABG:

• ↑ pH

• ↑ HCO₃⁻

👩‍⚕ Nursing Actions:

• Stop vomiting or NG suction

• Replace electrolytes (esp. potassium & chloride)

• May give acetazolamide (diuretic that helps excrete bicarb)