Diabetes Insipidus

Question 1

Diabetes insipidus

Answer 1

Condition of insufficient ADH that results in the inability of the body to concentrate or retain water
Produces large volumes of dilute urine

Question 2

How much urine can be excreted daily?

Answer 2

Varies from 4 L to 20 L/day

Question 3

Characteristics of urine

Answer 3

Dilute
Low specific gravity
Low osmolarity
Increased plasma osmolarity

Question 4

Central Diabetes Insipidus

Answer 4

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

Question 5

Nephrogenic Diabetes Insipidus

Answer 5

Caused by inadequate kidney response to the presence of ADH

Rare

Question 6

Psychogenic Diabetes Insipidus

Answer 6

Water intoxication due to psychiatric disturbance

The uncontrollable urge to drink

Question 7

Pathophysiology of diabetes insipidus

Answer 7

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

Question 8

What can happen if thirst mechanism is poor or absent?

Answer 8

Severe dehydration and death can occur

Question 9

Cardiovascular clinical manifestations

Answer 9

Hypotension (postural)
Decreased pulse pressure
Tachycardia
Weak peripheral pulses
Hemoconcentration 
-Increased hbg and hct
-Increased BUN

Question 10

Renal clinical manifestations

Answer 10

Increased urine output with dilute, low specific gravity, hyposomolar

Question 11

Integumentary clinical manifestations

Answer 11

Dehydration
Poor turgor
Dry mucous membranes

Question 12

Neurologic clinical manifestations

Answer 12

Increased sensation of thirst
Irritability, headache
Decreased cognition
Hyperthermia
Lethargy to coma
Ataxia
Hypernatremia

Question 13

What are most clinical manifestations related to?

Answer 13

Dehydration

Question 14

How do you diagnose diabetes insipidus?

Answer 14

Health and physical
CT/MRI of brain
Fluid deprivation test

Question 15

Fluid deprivation test

Answer 15

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

Question 16

Low specific gravity for dilute urine

Answer 16

Less than 1.005

Question 17

Low osmolarity

Answer 17

Less than 100mOsm/kg

Question 18

Management of central diabetes insipidus

Answer 18

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

Question 19

Chlorpropamide

Answer 19

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

Question 20

Desmopressin (central DI)

Answer 20

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

Question 21

Vasopressin (central DI)

Answer 21

Helps prevent loss of water from body by reducing urine output and helping kidneys reabsorb water into body
Follow orders for fluid intake

Question 22

Hydrochlorothiazide (nephrogenic DI)

Answer 22

Thiazide diruetic

Helps prevent body from absorbing too much salt

Question 23

Indomethacin

Answer 23

NSAID

May increase risk of fatal HA or stroke if used long term or high doses

Question 24

Nephrogenic diabetes insipidus management

Answer 24

Dietary management (low sodium diet, less than 3 grams per day, low protein)
Thiazide diuretics
NSAID
-PPIs are given to prevent gastric ulcers

Question 25

Nursing Diagnosis

Answer 25

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

Question 26

Assessment

Answer 26

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

Question 27

Interventions

Answer 27

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

Question 28

Evaluation and outcome

Answer 28

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?