Diabetes Insipidus Flashcards
Diabetes insipidus
Condition of insufficient ADH that results in the inability of the body to concentrate or retain water
Produces large volumes of dilute urine
How much urine can be excreted daily?
Varies from 4 L to 20 L/day
Characteristics of urine
Dilute
Low specific gravity
Low osmolarity
Increased plasma osmolarity
Central Diabetes Insipidus
Caused by a defect in the hypothalamus or pituitary gland, resulting in a lack of ADH production or release
Also occurs with increased cranial pressure
Kidneys go into overdrive
Nephrogenic Diabetes Insipidus
Caused by inadequate kidney response to the presence of ADH
Rare
Psychogenic Diabetes Insipidus
Water intoxication due to psychiatric disturbance
The uncontrollable urge to drink
Pathophysiology of diabetes insipidus
Hyposecretion of ADH and a deficiency of vasopressin
Results in failure of tubular reabsoprtion of water in kidneys leading to polyuria and dehydration
Dehydration increases plasma osmolarity
Stimulates osmoreceptors
Relays sensation of thirst
What can happen if thirst mechanism is poor or absent?
Severe dehydration and death can occur
Cardiovascular clinical manifestations
Hypotension (postural) Decreased pulse pressure Tachycardia Weak peripheral pulses Hemoconcentration -Increased hbg and hct -Increased BUN
Renal clinical manifestations
Increased urine output with dilute, low specific gravity, hyposomolar
Integumentary clinical manifestations
Dehydration
Poor turgor
Dry mucous membranes
Neurologic clinical manifestations
Increased sensation of thirst Irritability, headache Decreased cognition Hyperthermia Lethargy to coma Ataxia Hypernatremia
What are most clinical manifestations related to?
Dehydration
How do you diagnose diabetes insipidus?
Health and physical
CT/MRI of brain
Fluid deprivation test
Fluid deprivation test
Baseline body weight, urine volume, urine osmolality, and specific gravity
NPO for 8-12 rhs
Administer desmopressin (DDAVP) intranassaly or subcutaneously
30-60 minutes after administration, obtain urine and serum osmolality and compare to baseline
CENTRAL DI: urine Osm > 300 decreased output
NEPHROGENIC DI: not much change
Low specific gravity for dilute urine
Less than 1.005
Low osmolarity
Less than 100mOsm/kg
Management of central diabetes insipidus
Do not restrict oral intake IVF: hypotonic solutions Drug therapy includes: -Desmopressin acetate (DDAVP) - with URTI, oral, or SQ vasopressin used -Vasopressin tannate -Oral: chlorpropamide, carbamazepine
Chlorpropamide
Sulfonylureas
Helped to control high blood sugar, treat type 2 diabetes with diet and exercise
May make you more sensitive to the sun
Do not use if you have type 1 diabetes, DKA, severe liver, kidney, thyroid, endocrine problems
Take in morning with breakfast
If you miss dose, take as soon as you remember, do not miss any doses
Desmopressin (central DI)
Antidiuretic hormone
Causes the kidneys to produce less urine
Do not use if you have moderate kidney problems or a history of low blood sodium levels
Vasopressin (central DI)
Helps prevent loss of water from body by reducing urine output and helping kidneys reabsorb water into body
Follow orders for fluid intake
Hydrochlorothiazide (nephrogenic DI)
Thiazide diruetic
Helps prevent body from absorbing too much salt
Indomethacin
NSAID
May increase risk of fatal HA or stroke if used long term or high doses
Nephrogenic diabetes insipidus management
Dietary management (low sodium diet, less than 3 grams per day, low protein)
Thiazide diuretics
NSAID
-PPIs are given to prevent gastric ulcers
Nursing Diagnosis
Impaired urinary elimination r/t polyuria
Confusion r/t dehydration and hyperosmolality
Fluid volume deficit r/t polyuria
Knowledge deficit r/t diagnosis, tests, and treatment
Risk for altered body temp r/t dehydration
Assessment
Recent hypophysectomy, head trauma, brain tumor, infection, or use of drugs that inhibit ADH release
Obtain a list of current and past medications
Does individual complain of urinary frequency or excessive thirst?
Signs of dehydration (fluid and electrolytes)
Bladder distention
Interventions
Monitor VS and neuro/cardio status
Provide safe environment, particularly in the cliant with change in LOC or mental status
Monitor electrolyte values and for signs of dehydration
Monitor I/O, daily weights, specific gravity of urine
Maintain intake of adequate fluids
Instruct client to avoid foods/liquids with diuretic type action
Administer DDAVP or thiazide diuretics with NSAIDs as indicated
Monitor for over treatment with DDAVP (weight gain w/ fluid overload or water retention, headache, hyponatremia, change in LOC)
Limit sodium to less than 3 g and do not restrict water intatke
Evaluation and outcome
Has client noted a decrease in urinary frequency and excessive thirst?
Are I/O, specific gravity, lab values normalized?
Is client able to verbalize understanding of disease process, test, and care needs?
Is client compliant with therapy?
