Diabetes Insipidus
Describe the 3 phases of central DI following intracranial surgery?
1. An abrupt onset of polyuria 2. Urine volume normalizes 3. Central DI is permanent
What are 2 other ADH replacement drugs?
1. Aqueous vasopressin (Pitressin) 2. Lysine vasopressin (Diapid)
What 2 medications are used to help decrease thirst associated with central DI?
1. Chlorpropamide (Diabinese) 2. Carbamazepine (Tegretol)
What is the primary characteristic of DI?
1. Excretion of large quantities of urine (2 to 20 L/day) 2. Very low specific gravity (less than 1.005) 3. Urine osmolality of less than 100
What 4 routes can DDAVP be given?
1. Oral 2. IV 3. Subcutaneously 4. Nasal spray
If oral intake of fluids cannot keep up with urinary losses, severe dehydration results? What are its manifestations?
1. Poor skin turgor 2. Hypotension 3. Tachycardia 4. Hypovolemic shock
What 5 things should the nurse monitor?
1. Pulse 2. BP 3. Level of consciousness 4. Fluid intake and output 5. Urine specific gravity
What things should the nurse assess for in the response to DDAVP?
1. Weight gain 2. Headache 3. Depression 4. Restlessness 5. Hyponatremia
What are the medications used in nephrogenic DI?
1. hydrochlorothiazed (HydroDIURIL) 2. Chlorothiazide (Diuril)
When does the third phase of DI occur after surgery?
10 to 14 days post-op
How is nephrogenic DI managed and why?
Because the kidney is unable to respond to ADH in nephrogenic DI, hormone therapy has little effect. Instead the treatment includes a low-sodium diet and thiazide diuretics.
What is the hormone replacement of choice for central DI?
DDAVP, an analog of ADH
What is the cornerstone of treatment for central DI?
Fluid and hormone therapy
What electrolyte imbalance might a patient with DI have? Why?
Hypernatremia caused by pure water loss in the kidneys
Which solution is used in the management of acute DI?
IV hypotonic saline or dextrose 5% in water to replace urine output
What is the next step in caring for the patient with nephrogenic DI if initial management is not effective?
Indomethacin (Indocin) may be prescribed, and NSAID that helps increase renal responsiveness to ADH
What should the nurse keep a record of to determine fluid volume status?
Intake and output and daily weights
What are the dietary restrictions in nephrogenic DI?
Low-sodium no more than 3 g/day to decrease urine output
What is the therapeutic goal for DI?
Maintenance of fluid and electrolyte balance
What 4 things must the nurse monitor for in a patient with diabetes insipidus who is acutely ill? How often?
May be required hourly: 1. Blood pressure 2. Heart rate 3. Urine output 4. Specific gravity
What test differentiates central DI from nephrogenic DI?
Measure the level of ADH after an analog ADH is given. If the cause is central DI the urine is more concentrated.
What two things characterize DI?
Polydipsia and polyuria
Given the type of IV solution administered in acute DI, what should the nurse monitor in the patient and why?
Serum glucose levels because hyperglycemia and glycosuria can lead to osmotic diuresis, which increases the fluid volume deficit
When monitoring for signs of dehydration, what are 5 things that the nurse should look for?
Signs of acute dehydration: 1. Alertness 2. Response to stimuli 3. Mucous membranes 4. Tachycardia 5. Skin turgor
How is central DI identified?
Water deprivation test. The patient is deprived of water for 8 to 12 hours and then given desmopressin acetate subq or nasally.