Pituitary Gland Notes

Posterior Pituitary Gland

Neurohypophysis → Derived from Hypothalamus

Anterior Pituitary Gland

Adenohypophysis → Derived from GI Tract

Germ Layers

1. Endoderm (innermost)

2. Mesoderm (middle)

3. Ectoderm (outermost)

Disorders of the Posterior Pituitary Gland

Diabetes Insipidus

Leads to massive polyuria

Symptoms of Diabetes Insipidus

1. Polyuria

2. Polydipsia

4 Causes of Diabetes Insipidus

1. Pituitary Surgery

2. Inflammation

3. Tumor - Brain/Astrocytoma (common)

4. Trauma

Diagnostics of Diabetes Insipidus

1. Water Deprivation Test - NPO for 4 to 5 hours

2. Urine Specific Gravity - Normal Range: 1.015 to 1.030

18 months

Anterior Fontanelle of the baby closes by

2 to 3 months

Posterior Fontanelle of the baby closes by

Pediatric Dehydration Sign

Tachycardia/Elevated Heart Rate

Postural Hypertension

Sudden ↓ in BP when changing position

Complication of Diabetes Insipidus

Hypovolemic Shock

Nursing Management of Diabetes Insipidus

1. Force fluid - 2 to 3 Liters

2. Monitor weight

3. Restrict salty processed food

4. Monitor I & O

5. Hypotonic Solution - LR/PLR

6. Safety

Drug of Choice for Diabetes Insipidus

1. Vasopressin/Pitressin

2. Desmopressin

   • Intranasal - Better absorption WOF: Irritation

   • Subcutaneous

Disorders of the Posterior Pituitary Gland

Syndrome of Inappropriate Antidiuretic Hormone (SIADH)

• An only endocrine disorder that leads to Water Intoxication

• Due to Bronchogenic Cancer/Oat Cell

• Water Intoxication → Cerebral Edema → Increased ICP → Seizure

Complication of SIADH

↑ ICP

Monro-Kellie Hypothesis

1. Brain Mass - 80%

2. Cerebrospinal Fluid - 10%

3. Blood - 10%

Hypovolemic Shock

1. Hyponatremia

2. Hypothermia

3. Tachycardia

4. Tachypnea

5. Cold Clammy

Increased ICP

1. Hypertension

2. Hyperthermia

3. Bradycardia

4. Bradypnea

5. Warm to touch

Cushing’s Triad

1. Hypertension

2. Hyperthermia

3. Bradycardia

Assessment of SIADH

1. Tachycardia

2. Anorexia

3. Nausea and Vomiting

4. Hyponatremia

5. Low Urinary Output

Nursing Management of SIADH

Monitor for signs of ↑ ICP

Complication of Hyponatremia

Seizure

Level of Consciousness (LOC)

First to change before VS

Common Diuretics for SIADH

1. Osmotic Diuretics - Rapid IV push to prevent crystallization

2. Loop Diuretics

Magnesium Sulfate (MgSO4)

Flushing Syndrome (Mannitol)

Disorders of the Anterior Pituitary Gland

Hypopituitarism

• 1 or more pituitary hormone secreted

• Dwarfism

Signs and Symptoms of Hypopituitarism

1. Mild to moderate obesity

2. ↓ Cardiac Output

3. Infertility

4. Fatigue

5. ↓ BP

6. Tumors

Management of Hypopituitarism

Hormonal Replacement

Disorders of the Anterior Pituitary Gland

Hyperpituitarism

Hypersecretion of growth hormone

Hyperpituitarism in Pediatric

• Gigantism (8 ft)

• Common to children

Hyperpituitarism in Adult

Acromegaly

Drug of Choice for Hyperpituitarism

• Sandostatin/Octreotide Acetate

• Administer SQ!

Surgical Management of Hyperpituitarism

Transsphenoidal Hypophysectomy

Complication of Transsphenoidal Hypophysectomy

1. Bleeding

2. Meningitis

3. Hypopituitarism

4. ↑ ICP

Postoperative Management of Transsphenoidal Hypophysectomy

1. Semi-fowlers position

2. Monitor signs of ↑ ICP

3. Hormonal Replacement

4. Do not use straw as it can cause CSF leakage

5. Do not blow nose