
.png)
Diabetes Insipidus
"NOT actual Diabetes"
Zero to Finals
Pathophysiology
This is the most common disorder of the posterior lobe of the pituitary and is characterized by a deficiency of vasopressin or ADH (Antidiuretic Hormone).
This disorder is caused by a hormonal abnormality and is NOT related to diabetes. It results in a disorder of salt and water metabolism marked by great thirst and extreme urinary output due to the kidney's inability to prevent the excretion of water.
Etiology
Several causes of DI are possible.
Normally, when your kidneys filter your blood, only a small amount is excreted as urine. ADH, produced by the hypothalamus and stored in the pituitary gland, controls how much urine is excreted by the kidneys and when ADH is not present (Central DI) or the kidneys do not react adequately to the ADH (Nephrogenic DI), excessive excretion occurs.
Central DI:
-
Caused by damage to the hypothalamus or pituitary gland
-
Genetics
-
Head Trauma
-
Infection
-
Loss of Blood supply to the pituitary
-
Surgery
-
Tumor
Nephrogenic DI:
-
Caused by a defect in the kidneys
-
Genetics
-
Drugs - Lithium
-
Infection
-
High levels of serum calcium
Lab & Diagnostics
Labs and diagnostics for Diabetes Insipidus include:
-
Fluid Deprivation Test
-
Plasma and urine osmolality studies
-
ADH Plasma Level Tests
-
Desmopressin Therapy
-
Imaging, CAT or MRI to check for a tumor
Signs & Symptoms
S/S of Diabetes Insipidus include:
-
Extreme thirst
-
Producing large amounts of diluted urine
-
Frequent need to get up to urinate during the night
-
Preference for cold drinks
-
In a serious case, urine output can be as much as 19 liters a day if you're drinking a lot of fluids. A normal adult outputs between 1 and 2 liters per day.
Risk Factors
Risk factors for Diabetes Insipidus include:
-
Genetic (Usually affects males, but the gene can be passed from the mother to the child
Treatment
Medical:
-
ADH Replacement Therapy
-
Adequate Fluid Replacement
-
If Nephrogenic, other medical treatment will be needed
Pharmacologic:
-
Desmopressin (DDAVP)
-
Chlorpropamide (Diabinese)
-
Thiazide Diuretics
Nursing
Interventions
The top priority for nurses is physical assessment and patient education. Fluid Management, and pharmacologic management as ordered are also key during home care or hospitalization.
Patient Education:
-
Pt, Family and/or caregiver must be educated about follow-up care, complication prevention, and emergency care.
-
When giving verbal directions, the nurse must be specific and clear in the directions and give written instructions on medications, including the dose, actions, side effects and the S/S of hyponatremia (low levels of serum sodium).
-
The nurse should advise the patient to wear a medical bracelet, and carry meds and DI info at all times.