Syndrome of Inappropriate Antidiuretic Hormone Secretion or SIADH is a disorder of sodium and water balance characterised by hypotonic hyponatraemia and impaired urinary dilution in the absence of renal disease or any identifiable physiological (osmotic or nonosmotic) stimulus known to release vasopressin.
SIADH is characterized by excessive release of antidiuretic hormone from the posterior pituitary gland or another source. The result is often fluid overload leading to dilutional hyponatremia. It was originally described in people with small-cell carcinoma of the lung, but it can be caused by a number of underlying medical conditions.
Some common causes of SIADH include:
- Meningitis
- Head injury : Subarachnoid hemorrhage
- Cancers : Lung cancer (especially small-cell lung cancer, as well as other small-cell malignancies of other organs)
- Infections : Brain abscess, Pneumonia, Lung abscess
- Guillain-Barré syndrome
- Drugs : Chlorpropamide, Clofibrate, Phenothiazine, Ifosfamide, Cyclophosphamide, Carbamazepine, Selective serotonin reuptake inhibitors (SSRIs, a class of antidepressants), Methylenedioxymethamphetamine (MDMA, commonly called Ecstasy. SIADH due to taking ecstasy was cited as a factor in the death of Leah Betts), Oxytocin, Vincristine, Morphine, Amitriptyline
- Hypothyroidism
- sarcoidosis
Complication
- hyporuricemia
- fluid overload
- decrease in chloride levels (plasma or serum)
- decrease in osmolarity (plasma)
- hypokalemia
- hypomagnesemia
- increased levels of sodium (urine)
Management
Management objectives in SIADH are:
- Looking for the cause if possible
- Measure the liquid electrolyte is not balanced
- Prevent complications
Non-pharmacological management plan:
- Fluid restriction (control the possibility of excess fluid)
- Sodium restriction
Pharmacological management plan:
- Use of diuretics to remove fluid
- Demeclocycline drug use, to suppress vosopresin
- Special treatment = surgical procedure
Nursing Diagnosis for Syndrome of Inappropriate Antidiuretic Hormone Secretion or SIADH
1. Elimination disorders related to a decrease in urine volume.
2. Nursing Interventions for Imbalanced Nutrition Less than Body related to nausea, vomiting and anorexia
3. Excess Fluid Volume related to inhibition of normal ADH uncontrolled
4. Disturbed Thought Processes related to decreased levels of Na.
