Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Endocrinology > SIADH > Flashcards

SIADH Flashcards

(66 cards)

Start Studying
1
Q

What does SIADH/SIAD stand for?

A
  • Syndrome of Inappropriate Secretion of Antidiuretic Hormone
    OR
  • Syndrome of Inappropriate Antidiuresis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is osmolality?

A

A measure of the solute (Na, K, Cl) concentration in a unit of water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is anit-diuretic hormone (ADH)?

A
  • Also called Arginine Vasopressin.

- Produced by the hypothalamus and stored in the posterior pituitary gland.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 2 primary functions of ADH?

A
  • Regulates water retention in Kidneys

- Vascular constriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

SIADH is a result from?

A
  • Hyponatremia and hypo-osmolality
  • Resulting from inappropriate, continued secretion or action of ADH despite normal or increased plasma volume, which results in impaired water excretion.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Hyponatremia is a result of what?

A

Hyponatremia is a result of an excess of water rather than a deficiency of sodium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

In general, SIADH is due to what 3 things?

A
  1. Elevated levels of ADH
    2: Water retention
    3: Loss of or dilution of certain electrolytes or solutes (Na, K, Cl)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the most important effect of ADH?

A

Conserve water by reducing water loss through the kidneys.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Higher ambient temperatures causes what?

A

Loss of water via sweat.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Increased plasma osmolarity causes what?

A

A concentration of blood solutes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the pathophysiology of ADH (Vasopressin)?

A
  • Vasoconstrictor.
  • Synthesized in the hypothalamus .
  • Stored in the posterior pituitary.
  • Endocrine negative feedback mechanism from Osmoreceptors in hypothalamus.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the kidneys response to ADH?

A
  • ADH increases the permeability of the distal convoluted tubules in the nephrons
  • This allows for water reabsorption, thus preventing water loss.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

ADH activity dilutes what?

A

ADH activity dilutes blood levels of solutes.

- water reabsorption NOT solute absorption.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the CNS response to ADH?

A
  • Dysarthria: Slurred or slow speech
  • Lethargy
  • Confusion
  • Delirium
  • Seizures
  • Coma(frombrain swelling)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Most cases of SIADH have what etiology? and what are most caused by?

A
  • Cancer etiology

- 70% are caused by Small Cell Lung CA .

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where are some ADH producing tumors?

A
  • Carcinomas (Small Cell)
  • Bronchogenic
  • Pancreatic
  • Prostatic
  • Duodenal
  • Colon
  • Thymoma
  • Thymus gland
  • Leukemia
  • Lymphoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are common causes of SIADH in pulmonary disease?

A
  • Asthma
  • Pneumonia
  • Tuberculosis
  • Lung Abscess
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the CV responses to ADH?

A
  • ADH increases peripheral vascular resistance and thus increases arterial blood pressure.
  • Becomes an important compensatory mechanism for restoring blood pressure in various forms of hypovolemic shock
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the forms of hyopvolemic shock?

A
  • Dehydration
  • Bleeding
  • Vomiting
  • Burns
  • Diuretics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are common causes of SIADH in CNS disorders?

A
  • Meningitis / Encephalitis
  • CVA
  • Brain Abscess
  • Intracranial hemorrhage
  • Cerebral aneurysm
  • Subdural bleeds
  • Head trauma
  • Vascilitis: Lupus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What drugs cause SIADH?

A
  • Antibiotics: Ciprofloxin
  • SSRI’s: Fluoxetine (Prozac)
  • TCAs
  • Carbamazepine (Tegretol):
  • Chlorpropamide: Sulphonylurea
  • Cyclophosphamide: tx of Lymphoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What level of sodium is indicative of hyponatremia?

A

<135 mEg/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are sxs of sodium <130?

A
  • Weakness
  • Weight gain
  • HA
  • Anorexia
  • Lethargy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are sxs of sodium <115?

A
  • Mental status changes
  • Seizures
  • Coma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are neurological sxs of SIADH?
- Irritability - Personality changes - HAs - Combativeness - Confusion - Hallucinations - Seizures - Coma - Decreased Reflexes
26
What are GI sxs of SIADH?
- Nausea - Vomiting - Muscle cramps
27
What are medical comorbidities of SIADH?
- CHF - Liver failure - Renal failure - Pneumonia
28
Hyponatremia is recognized only secondary to the comorbidity sxs such as what?
- Dyspnea - Jaundice - Uremia - Cough
29
The recognition of SIADH is entirely what? and pts may develop clinical sxs d/t what?
- Entirely incidental. | - Sxs may be d/t the cause of hyponatremia or hyponatremia itself.
30
What labs/imaging should you consider for SIADH workup?
- CBC - CMP - Plasma Cortisol - CT of the head: Meningitis - CXR: SCLC - Radioimmunoassay of ADH
31
What IV solutions should you use for tx of SIADH?
- Isotonic (no shift of intra or extra cellular fluids) - Hypotonic (shifts fluid into cells) - Hypertonic (shift fluids out of cells)
32
What are some Isonotic solutions?
- Normal Saline (NS - 0.9% Saline) - Lactated Ringers (LR) - Dextrose and Water (D5W)
33
Why should you be cautions of D5W?
- The glucose quickly metabolizes in the system and becomes hypotonic solution and can complicate what you are trying to accomplish
34
What are the indications of isotonic IV solution?
- Volume expander - Dilute medications - To Keep vein Open (TKO)
35
What are the CI of isotonic IV solution?
Volume overloaded patients
36
What are examples of hypotonic IV solutions?
- 2.5 NS - .33 NS - .45 NS
37
What are the indications of hypotonic IV solution?
Cellular hydration
38
What are the CI of hypotonic IV solution?
- Hypotension (Decreased BP) | - Increased Intra Cranial Pressure (ICP)
39
What are examples of hypertonic IV solutions?
- D5 1/2, - D5 NS - D5 LR
40
What are the indications of hypertonic IV solution?
- Hypovolemia - Fluid expansion - Increased urine output
41
What are the CI of hypertonic IV solution?
- Renal failure | - Cardiac patients
42
What is the tx for SIADH?
- Treating underlying causes - Fluid restriction of 800-1,000 ml/day to increase serum sodium. - Intravenous saline
43
IV saline should only be used in what type of pts?
Symptomatic patients: severe confusion, convulsions, or coma
44
What is the Na content in D5W, 0.45% Saline, 0.9% Saline, 3% Saline?
D5W: 0 0.45% Saline: 77 0.9% Saline: 154 3% Saline: 513
45
There are drugs used for tx in SIADH but what should we do in primary care before starting medication?
TURF TURF TURF
46
What are causes of hyponatremia?
- Vomiting - Diuretics - SIADH - Burns, wound drainage - Excessive water intake - Excessive administration of IV D5W
47
What are causes of hypernatremia?
- Hyperventilation - Inadequate water ingestion - Diabetes insipidus - Ingesting large amount of saltwater - Ingestion of OTC drugs such as Alka-Seltzer - Hypertonic tube feedings w/o water supplements
48
What are the sxs of hyponatermia <135?
- Nausea - Muscle cramps - Confusion - Muscular twitching - Headache - Seizures - Coma
49
What are the sxs of hypernatermia >145?
- Elevated temperature - Weakness - Disorientation - Irritability and restlessness - Thirst - Dry, swollen tongue - Sticky mucus membranes - HTN - Tachycardia
50
What are the causes of hypokalemia <3.5?
- Gastric Suction - Vomiting - Prolonged diarrhea - Diuretics and Steroids - Inadequate intake
51
What are the causes of hyperkalemia >5.3?
- Renal failure - Use of K+ supplements - Burns - Crushing injuries - Severe infection (Sepsis)
52
What are the sxs of hypokalemia <3.5?
- Anorexia, N/V - Weak peripheral pulses - Muscle weakness, paresthesias, decreased DTR’s - Impaired urine concentration - Ventricular dysrhythmias - Increased instance of digitalis toxicity - Shallow respirations
53
What are the sxs of hyperkalemia >5.3?
- EKG changes: Peaked T waves with wide QRS complexes - Dysrhythmias: V-Fib, CHB - Cardiac arrest - Muscle twitching and weakness - Numbness in hands, feet, and circum-oral - Nausea - Diarrhea
54
What is Diabetes Insipidus (DI)?
An uncommon condition in which the kidneys are unable to prevent the excretion of water.
55
Those with DI have a normal level of what?
Normal Glucose levels, but their kidneys are not able to balance fluid in the body.
56
What are similarities of DI and DM?
If both are left untreated DI and DM cause constant thirst and frequent urination.
57
DI is a polyuric disorder which means what?
- Insufficient production of Vasopressin OR - Unresponsiveness of the renal tubules to Vasopressin
58
Insufficient production of Vasopressin is known as what 2 types of DI?
- Pituitary DI | - Neurogenic DI
59
Unresponsiveness of the renal tubules to Vasopressin is known as what type of DI?
Nephrogenic DI
60
What is the MC etiology of DI?
Meningitis
61
What are some causes of Neurogenic DI?
- Idiopathic - Head trauma - Meningitis - Neoplasm - MS
62
What are some causes of Nephrogenic DI?
- Drugs: Lithium, Aminoglycosides, Antivirals - Metabolic: HyperNa, HypoK - Sarcoidosis - Sickle Cell Disease - Low protein diets
63
What are some DDx of DI?
- DM - Polydipsia med: Thorazine (for hiccups) - Osmotic diuresis: glucose, mannitol - Psych polypisia: electrolyte disturbances
64
What are some PE and clinical presentations of DI?
- Abrupt onset - Nocturia - Polyuria: 2.5 – 6 Liters / Day - Polydipsia - Neurologic manifestations: Seizures, HA, visual field defects
65
What is the primary work up of DI?
Showing the polyuria is caused by the inability to concentrate urine resulting in: - decreased vasopressin production or - insensitivity to vasopressin
66
What is the basic treatment of DI?
Endocrinology consultation for diagnostic testing, referral, and structured treatment plan.

Endocrinology (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions