SIADH and Diabetes Insipidus Flashcards

Flashcards based on lecture notes about SIADH and Diabetes Insipidus.

SIADH

Excessive release of antidiuretic hormone

Hyponatremia

Increased water retention without an increase in sodium, diluting the blood and causing low sodium

Euvolemia

Elevated fluid volume

SIADH Characteristic

Low serum osmolality

Hypervolemia in SIADH

Often transient due to natriuretic mechanisms

Aquaporins

Water reabsorption

Causes of SIADH

CNS disorders, tumors, drugs, surgery, infections, inherited forms

Symptoms of SIADH

Asymptomatic, nausea/vomiting, obtundation, headaches, seizure, respiratory arrest, coma

Treatment for SIADH

ADH antagonist, treat cause, limit fluids

Normal Urine Osmolality

Normal: 500 mOsm/kg

Normal Urine Specific Gravity

Normal: 1.005-1.030

Normal Serum Osmolality

Normal: 280-300

Normal Serum Sodium

Normal: 135-145

SIADH Mnemonic

"Soaked Inside"

Diabetes Insipidus Mnemonic

"Dry Inside"

First Intervention for SIADH

Treat underlying cause

Free Water Restriction for SIADH

Restrict 1 to 1.5L per day

Salt Tablets for SIADH

Start with 1g NaCl PO TID

Urea Powder for SIADH

15-30g PO daily

Vasopressor Antagonists

Blocks ADH receptor

Diabetes Insipidus Definition

Condition causing extreme thirst and excessive urination

Kidney Function in Diabetes Insipidus

Kidney is unable to conserve water

Cause of Diabetes Insipidus

Deficiency of ADH (Vasopressin)

Symptoms of Diabetes Insipidus

Extreme thirst and frequent urination

Causes of Central Diabetes Insipidus

Brain tumors, pituitary surgery, brain injuries

Causes of Nephrogenic Diabetes Insipidus

Medications (lithium), kidney disease, genetic disorders

Gestational Diabetes Insipidus

Breakdown of vasopressin by the placenta during pregnancy

Dipsogenic Diabetes Insipidus

Problems with the hypothalamus, mental health conditions

Excluding Diabetes Mellitus

Urinalysis, capillary blood glucose

Confirming True Polyuria

Check 24h urine volume

Confirming true polyuria - Step 2

Measure paired serum/urine osmolality

Urine concentration in SIADH

Concentrated urine

SIADH Water retention

Increased water retention, without an increase in Na+.

SIADH - Effect on Brain

H2O causes brain swelling and neuron dysfunction

Urea powder action in SIADH

Induces osmotic water elimination by promoting passive sodium reabsorption

Normal Saline - Side effect

Volume overload

SIADH Underlying Causes

Can cause pain, primary lung pathology, post-operative phenomenon, medications

Altered Hormonal and Metabolic Regulations

SIADH - Hyponatremia and Euvolemia

Hormonal & Metabolic Regulations

Diabetes Insipidus & SIADH

Classic symptom of DI

Extreme thirst

Classic symptom of DI

Excessive urination

Urine in DI

High output of very light-colored or clear urine

Defining Polyuria

24h urine volume >3L

ADH antagonist function

Blocks ADH receptor

SIADH fluid limiting

Limit fluids.

SIADH and Low Sodium

Hyponatremia

Primary steps to treating SIADH

ADH antagonist, treat cause

SIADH and Brain

Brain swelling

Diabetes Insipidus Definition

Kidney unable to conserve water.

Definition of Diabetes Insipidus

extreme thirst and excessive urination

SIADH intervention

Normal Saline

Result of SIADH

Water and sodium retention

Underlying causes of SIADH

Pain

Underlying causes of SIADH

Lung pathology

Underlying causes of SIADH

Medications can cause.

what happens in SIADH

Excessive ADH secretion

Hyponatremia

Low serum osmolality

normal serum osmolality

280-300

SIADH lab tests

Hyponatremia with Low serum osmolality

treat SIADH

ADH antagonist

Causes Nephrogenic DI

Lithium

Causes of Central DI

Infection and inflammation (meningitis)

Causes of Central DI

Brain Tumors

Causes of Dipsogenic DI

problems with the hypothalamus

Confirming True Polyuria

24h urine volume >3L

Causes of Nephrogenic DI

Kidney dz.

Excessive release of

ADH

Syndrome of Inappropriate

excessive ADH

Treabsorption

reabsorption

Concentrated

urine

disorders

CNS

Drugs (i.e. analgesics, antiseizures,

SSRIs

SIADH

Surgery

forms

Inherited

Asymptomatic, nausea/vomiting, obtundation, headaches,

seizure

ADH

antagonist

SIADH

DI

Gravity

Normal: 1.005-1.030

Subure

Bride

Free water

restriction

0.9% Normal

saline

antagonists

Vasopressor

A condition that causes extreme

thirst

The - is unable to conserve water

kidney

urine each time you urinate

light

resolves after delivery

pregnancy

Infection and inflammation

meningitis

disorders

autoimmune

disorders

autoimmune

mental health conditions

schizophrenia

Measure paired serum/urine

osmolality

Confirm true

polyuria

specialist investigation

refer

Possible diabetes

di

SIADH stands for Syndrome of Inappropriate

excessive ADH

Hyponatremia means

Low Sodium

Symptom of Diabetes Insipidus

Extreme thirst

Symptom of Diabetes Insipidus

Excessive urination

Main goal in treating SIADH

Treat the cause

SIADH affects on the brain

Brain swells with water