ADH

Nota:

• Deficiency of ADH hormone Responsible of retaining Water in the presence of High Sodium Concentration. In this Case The patient is Loosing Water which increases Sodium Levels. (Hypovolemia Hypernatremia). Increased Sodium Na+ Serum, Increased Serum Osmolality Concentration. Decreased Serum Osmality Concentration. 

1. Signs & Symptoms
   1. Diagnostics
      1. Specific Gravity of Urine Low (<1.005)
      2. Increased Serum Osmality

         Nota:

         • Less than 100mOsm/Kg
      3. Increase Hgb, Hct & BUN
      4. Increased Sodium
      5. Water Deprivation Test

         Nota:

         • Before Exam: Body weight and Urine Osmolality volume &amp; Specific Gravity is measured!  The patient is deprived water 8-12hrs and then given Desmopressin acetate Subcutaneously or Nasally. Patient with Central DI will Exibit a drastic increase of urine osmolality from 100 to 600mOsm/Kg and Decrease Urine Volume. Patient with Nephrogenic DI will not be able to increase Urine  Osmolality greater than 300mOsm/Kg
   2. Kidney /Urinary

      Nota:

      • 2 to 20L a day 
      1. Excessive Urine Output >200ml/hr

         Nota:

         • Greater than 200ml per hour
      2. Nocturia

         Nota:

         • Fatigue is due to excessive urination and also causes generalized muscle weakness. 
   3. Neurologic
      1. Irritability
      2. Decreased Cognition
      3. Thirsty
      4. Hyperthermia
      5. Lethargy, Coma, Ataxia
   4. Skin

      Nota:

      • Fatigue is the result of Nocturia of Frequenctly going to the bathroom. Generalized Weakness can Also Manifest. 
      1. Poor SKin Turgor
      2. Dry Mucous Membranes
   5. Cardiovascular
      1. Weak Peripheral Pulses, easily Obliterated
      2. Tachycardia

         Nota:

         • Viscosity of Blood is (thicker) so the Heart will compensate to get the tissue oxygenated. 
      3. Hypotension/ Decreased Pulse Pressure
2. Causes

   Nota:

   • Decreased Water Reabsorption in the Renal Tubules. Which leads to Decreased intravascular Volume. 
   1. Central

      Nota:

      • Interference with ADH synthesis, Transport or Release. 
      1. Brain Tumor
      2. Head Injury

         Nota:

         • Usually Self- Limiting 
      3. Brain Surgery

         Nota:

         • Intercranial Surgery- Triphasic Pattern: Acute excessive polyuria, Interphase Urine Normalizes, Third phase DI permanent (3rd phase 10-14days post-operatively) 
   2. Primary
      1. Structural Lesion in Thirst Center
      2. Psychological Disorder
   3. Nephrogenic

      Nota:

      • Inadequate Renal Response to ADH 
      1. Renal damage
      2. Drug Therapy (Lithium)
      3. Hereditary Renal Disease
3. Interventions
   1. On-Going Monitoring
      1. Daily Weights
      2. 24hr I&O
      3. Adequate Hydration (Copious) may be given orally or IV (Hypotonic Saline or D5W)
         1. IV Glucose Monitor Hyperglycemia

            Nota:

            • Hyperglycemia &amp; Glycosuria leads to Osmotic diuresis. This will lead to fluid volume deficit. 
      4. BP, HR (Tachycardia), Urine Output/specific gravity
      5. LOC

         Nota:

         • alertness, response to stimuli, 
      6. SKin turgor
   2. Central
      1. Desmopressin Acetate (DDAVP): Oral, IV, SC & Nasal Spray

         Nota:

         • Hormone Replacement Others: Aqueous Vasopressin, Lysine Vasopressin.  *Asssess Response: (Weight gain, Headache, Restlessness, Hyponatremia) 
      2. Chlorpropamide

         Nota:

         • ADH stimulator  (Synthetic Vasopressin) 
      3. Carbamezapine
   3. Patient Teaching
      1. Teach Patient About Close Follow-Up
   4. Nephrogenic
      1. Low Sodium Diet (no more than 3g)
      2. Thiazide Diuretics

         Nota:

         • May reduce flow to the ADH distal sensitive distal Nephrons
      3. Indomethacin

         Nota:

         • Used if Thiazide do not work. NSAID (Helps increase Renal Responsiveness)

Nota:

• Dilutional Hyponatremia (Euvolemic Hyponatremia) Caused by Overproduction of ADH homormone responsible for retaining water.  Serum Na+ Decreased, Decreased Serum Osmalality Concentration &amp; Increased Serum Osmlality Concentration. 

1. Causes
   1. MIscellaneous

      Nota:

      • Hypothyroidism, Lung infection, COPD, Positive pressure mechanical ventilation, HIV, Adrenal Insufficiency. 
   2. Drug Therapy

      Nota:

      • Carbamazepine, Chlorpropamide, General Anasthetics, Opioids, Oxytocin, Thiazide Diuretics, SSRI &amp; antidepressants, Tricyclic Antidepressants, Chemotherapy drugs, (Vincristine, Vinblastine, Cyclophosphamide)
   3. CNS disorders

      Nota:

      • Head injury, stroke, brain tumor, Infection (Encephalitis, meningitis), Cerebral Atrophy, Guillain Barre Syndrome, Systemic Lupus Erythematosus
   4. Malignant Tumors

      Nota:

      • pancreatic cancer, Lymphoid cancer, Thymus Cancer, Prostate Cancer, Colorectal Cancer
      1. Small Cell Lung Cancer

         Nota:

         • Most Common!!!
2. Signs & Symptoms

   Nota:

   • ADH increases Premeability at the Renal Distal Tubule &amp; Collecting Duct which leads to Reabsorption of Water into the Circulation. 
   1. Increased Body Weight

      Nota:

      • Without Edema 
   2. > 1.025 Urine Specific Gravity (Low Urine Output)
   3. Diagnostics
      1. Na+ Declines
      2. ECF expands
      3. GFR increases
      4. Plasma Osmality Decline

         Nota:

         • &lt;240mEq/L
   4. Pulmonary Edema
   5. Muscle Cramps & Generalized Weakness, Hyperreflexia
   6. Increased BP
   7. Cerebral Edema

      Nota:

      • This can Occur symptoms would include: Lethargy, confusion Headache, seizure, coma 
   8. Restless, Irritable, Apprehension

      Nota:

      • Headache 
   9. Anorexia, N&V, irritability, Thirst, Dyspnea on exertion & Fatigue 1st signs
3. Interventions
   1. Fluid Restriction NO more than 100mL a day
      1. Oral Care due to Discomfort of Oral Restriction
         1. Gum, Ice Chips Decrease Thirst
      2. Declomycin

         Nota:

         • The drug blocks effects on  the renal Tubules. 
   2. Strict I&O
   3. Daily Weight
   4. Neurologic Checks

      Nota:

      • Seizure Precautions
   5. Increase HOB no more than 10 degrees

      Nota:

      • Increase Venous return to the Heart &amp; Increase Left atrial filling Pressure.  Reducing the Release of ADH? 
   6. d/c Drugs that increase ADH production

      Nota:

      • Chlorpropamide, carbamezapine, oxytocin, thiazide, diuretics, SSRI antidepressants &amp; Some Chemo Drugs.
   7. Diuretics (125mEq/L)

      Nota:

      • If below the patient may loose sodium ions with the water which is increased risk for seizure. Also causes loss of K+, Ca+ &amp; Mg2+ loss may need supplements. 
      1. Furosemide
   8. Severe Hyponatremia (Seizures)
      1. 3% Hypertonic Saline
   9. Pharmalogical Therapy

      Nota:

      •  Euvolemic Hyponatremia Medication Treatments
      1. Tolvaptan
      2. Conivaptan

Nota:

• Anitdiuretic Hormone is produced from the Hypothalamus.

1. Posterior Pituitary

   Nota:

   • Anitdiuretic Hormone Stored &amp; Produced in the Posterior Pituitary.