Critical Endocrine Dysfunction 2

SIADH: Pathophysiology

•In SIADH there is an inability to suppress the secretion of ADH resulting in impaired water excretion leading to increased blood volume and decreased blood osmolality.

•Intake of water is greater than the excreted urine output leading to hyponatremia.

•Hyponatremia is a result of excess water retention because sodium level does not change with the excess of water.

SIADH: Pathophysiology cont.

•Blood becomes hypo-osmolar because the amount of sodium becomes diluted with increased water volume in the intracellular and extracellular fluids.

•Urine becomes hyperosmolar because kidneys continue to secrete sodium while urine output decreases.

SIADH: Causes

•Malignancies (small lung cell cancer)

•Medications (chemo- cisplatin, vincristine, cyclophosphamide, methotrexate)

• carbamazepine, oxcarbazepine, chlorpropamide, selective serotonin reuptake inhibitors (SSRI)

Hormone Deficiencies

• Hypothyroid

• Hypopituitary

Central Nervous System Disorders SIADH Cause

•Stroke

•Hemorrhage

•Infection- Pneumonia, HIV, Meningitis

•Trauma

•Surgery of Pituitary Gland

Idiopathic SIADH has

been identified in clients who have hyponatremia and hypoosmolality for which no underlying pathology had been determined.

However, in some cases, a malignancy was later discovered.

SIADH: Lab & Diagnostic Studies

•ADH level

•Serum/Urine osmolality

•Serum/Urine sodium- HYPONATREMIA

•Renal/Liver function tests

•Thyroid tests

•Blood glucose- hyperglycemia

•Fasting lipid profile

•Serum potassium

•Chest X-Ray- pulmonary conditions

•CT Scan

SIADH: Clinical Presentation

•Neurological effects: headaches, confusion, tremors

•Neuromuscular effects: muscle cramps, hypOreflexia

•Urinary effects: decreased output of concentrated urine with high specific gravity (greater than 1.02)

•Gastrointestinal effects: nausea, vomiting, diarrhea, anorexia

•Respiratory effects: Respiratory failure (Na less than 115 mEq/L)

ALL R/T HYPONATREMIA

SIADH: Treatments/Therapies

•Monitor vital signs

•Monitor for neurological changes

•Monitor for low urine output with high specific gravity

•Monitor for hyponatremia- seizure, coma

SIADH: Treatments/Therapies cont

Assess hourly:

•Urine output

•Potassium

•Sodium 

Anticipate IV hypertonic fluids

Medications to prevent hyponatremia

Foley catheter placement

An infusion of

0.9% sodium chloride may be given if the sodium level is greater than 120 mEq/L.

However, for symptomatic hyponatremia in SIADH, especially when the sodium level is below 120 mEq/L, a hypertonic IV fluid is administered.

A continuous infusion of 3% saline at 0.5 to 2 mL/kg/hr or up to three 100 mL boluses of 3% saline administered at 10-minute intervals is administered to increase the serum sodium level

Furosemide SIADH

Loop diuretic

inhibits the reabsorption of sodium and chloride from the loop of Henle and distal renal tubule and, in doing so, increases the excretion of water and sodium

Adverse reactions: hypotension, hypokalemia, exacerbation of hyponatremia, muscle spasms, and tinnitus.

Teach client to change positions slowly; may cause dizziness.

Tolvaptan SIADH

Oral vasopressin antagonist

treats hyponatremia by increasing the amount of water secreted as urine, thus increasing the serum sodium level

Adverse reactions: increase AST, ALT, bilirubin

Conivaptan SIADH

IV vasopressin antagonist

interferes with action at ADH receptors

Adverse reactions: hypotension, hypokalemia

may cause redness and pain at the IV site

Thyroid Storm: Pathophysiology

A thyroid storm, also known as a thyrotoxic crisis, is a life-threatening emergency in which multiple systems of the body are in a severe hypermetabolic state.

•Overstimulation of the entire metabolic system

•Increased demand for nutrients by body tissues

Thyroid Storm: Risk Factors

•Poorly managed or undiagnosed hyperthyroidism

•Abruptly stopping hyperthyroid medications

•Trauma

•Surgery

•Burns

•COVID-19

•DKA

•Pregnancy

•Infection

•Drug reaction

•Cardiovascular disease

•HTN

•Tachyarrhythmias

Thyroid Storm: Clinical Presentation

•High fever (104° F to 106° F) with sweating

•Cardiac manifestations- Tachycardia greater than 140 beats/min, May be life-threatening

•Neurological/behavioral

•Gastrointestinal N/V/D

•Enlarged thyroid

•Bulging eyes

•Hand tremor

•Jaundice

•Hyperreflexia

Thyroid Storm more Presentation

Heart/Liver failure

HTN

Cardiac arrest

Anxiety

Confusion

Agitation

Psychosis

Coma

Abdominal pain

GI Obstruction

Thyroid Storm: Lab and Diagnostic Testing

•Low TSH <0.350

•Elevated free T3 >1.46

•Elevated free T4 >398

•Abnormal liver function tests

•Hyperglycemia

•Elevated Calcium

•Low or high WBCs

•ECG

•Chest X-Ray

•Head CT

Thyroid Storm: Treatments/Therapies

•ABCs

•Monitor for arrhythmias

•Stabilize vital signs

•Minimize risk of organ damage

•Oxygen

•IV Fluids

•Temperature management

•Medication

•Surgery: Thyroidectomy

•Plasmapheresis- last resort