Endocrine Disorders Flashcards
(49 cards)
1
Q
What is thyroid crisis (storm)?
A
- Book calls it Thyrotoxicosis
- An acute, severe, and rare condition that occurs when excessive amts. of thyroid hormones are released into circulation.
- Severe form of hyperthyroidism
- Physical or psychological stressors (possible cause)
2
Q
Thyroid Crisis Etiology
A
- Thought to result from stressors (e.g., infection, trauma, surgery) in a patient w/ pre-existing hyperthyroidism (diagnosed or undiagnosed)
- Patients prone to thyroid crisis = those having thyroidectomy
- manipulation of hyperactive gland = increase in hormones released.
- Patients prone to thyroid crisis = those having thyroidectomy
3
Q
Pathophysiology of Thyroid Crisis
A
- Unsure
- Massive release of Thyroid Hormone
- Low tissue tolerance to triiodothyronine (T3) and thyroxine (T4)
- Release leads to hypermetabolic state – stimulation of the sympathetic nervous system
4
Q
Clinical Manifestation of Thyroid Crisis
A
- Sweating
- Heat intolerance
- Nervousness
- Tachycardia
- Wide Pulse Pressure
- Body Temp > 104o F without infection
- Seizure, Tremors
- Coma
5
Q
Previous medical Hx most often associated w/ thyroid crisis
A
Grave’s Disease
6
Q
Lab studies showing patient is in Thyroid Crisis?
A
- Elevated Total T4 and free T3 and T4
- Very low TSH
- Due to the elevated levels of thyroid hormoneo Decreased K+ and Mg+o Elevated Ca++
- LFTs (liver function test) may be elevated
- Hyperglycemia
- Insulin resistance and breakdown of stored glucose
7
Q
Management of thyroid crisis
A
4 Fold:
-
Precipitating Factors
- Stress, Trauma, MI, Shock
- Controlling Excessive Thyroid Hormone release
-
Inhibiting Thyroid Biosynsthesis
- Conversion of TH to T3 and T4
- Treat peripheral effects
8
Q
Drugs that Block Thyroid Synthesis
A
- Propyithiouracil (PTU)
- Methimazole
9
Q
Drugs that Suppress release of TH
A
- Sodium Iodide
- Potassium iodide
- Saturated solution of potassium iodine (SSKI)
- Dexamethasone (Glucocorticoid Steroid)
- Inhibit thyroid hormone release
10
Q
Beta Blocker used to treat Thyroid Crisis? How does it work?
A
- Propranolol (Inderal)
- Restore cardiac function
- Decreases catecholamine-mediated symptoms
11
Q
Other drugs used in the treatment of Thyroid Crisis?
A
- Digoxin
- Dilitazem
- Lasix
- Tx’s CHF, tachydysrhythmias
- Decrease myocardial O2 consumption and heart rate
- Tx’s CHF, tachydysrhythmias
12
Q
Emergency removal of excess circulation or hormone - How is it done?
A
- Plasmapherisis
- Dialysis
- Cholestyramine – oral
- Absorbs excessive hormone
13
Q
Management goals of Thyroid Crisis?
A
- Reducing circulating thyroid hormone levels and clinical manifestations w/ appropriate drug therapy
- The ultimate goal is to avoid reoccurrence
- Identify triggers
- Life long medications to suppress thyroid hormone
- Thyroid Ablation
14
Q
Thyroid Crisis Supportive Therapy
A
- Manage respiratory distress
- manage multi-system effect and responses to treatment -hourly!!
- Reduce fever
- Replace fluid
- Eliminate/manage initiating stressor
15
Q
Thyroid Crisis - Managing Cardiovascular status
A
- HR – Rhythm – Heart sounds – BP
- D5NS to treat hypovolemia
16
Q
Thyroid Crisis - managing body temperature
A
- Antipyretics
- Acetaminophen – Not ASA
- Increases free T3 and T4
- Tepid Baths
- Do not bring to shiver - ↑ Body temperature
17
Q
Thyroid crisis- neurologic status
A
- Seizure precaution
- ↓ LOC may lead to obstructed airway
18
Q
Thyroid Crisis - Radioiodine/RAI Therapy
A
- RAI therapy
- Definitive therapy
- Will make patient Hypothyroid
- Excreted in the urine - saliva
- Over a few dayso
- Do not share foods, drinkso
- Do not get close to children
- Definitive therapy
19
Q
How long does the acute phase of thyroid crisis last?
A
24-48 hours
20
Q
HYPOthyroidism Etiology
A
- Low levels of thyroid hormone
- Congenital – cretinism
- Detected at birth
- Primary thyroid failure
- Hashimoto’s disease
- Thyroiditis
- Low basal metabolic rate
21
Q
What is Myxedema Coma?
A
- Severe form of hypothyroidism
- Untreated hypothyroidism
22
Q
Precipitation factors of Myxedema Coma?
A
- Drugs (esp. opioids, tranquilizers, & barbiturates)
- Extreme cold
- Sedatives
- Surgery
- Opioids
- Infection
- Trauma
23
Q
Signs and Symptoms of Myxedema Coma
A
- Comatose
- Hypothermic
- Respiratory failure
- R/T muscle weakness
- Sleep apnea
- Cardiac failure
- R/T bradycardia
- Decreased stroke volume
24
Q
Significance of slowed drug metabolism and Myxedema Coma?
A
- Potential drug toxicity
- Digoxin
25
Myxedema Coma Treatment
* **Supportive**
* Ventilator
* Fluids
* Warming blankets – slowly
* Thyroid Hormones
* **T3 and T4**
* **Hydrocortisone** – IV
* If patient also has adrenal insufficiency
26
Adrenal Gland - Medullary hormones
* **Dopamine**
* Precursor of *Norepinephrine* (increase BP)
* **Norepinephrine**
* *↑ PVR* ( peripheral vascular resistance)
* **Epinephrine**
* *Fight of Flight* (HR Increase, dilates eyes, gets body ready to go)
* **Opioid peptides**
* *Not exactly to sure how they work.*
27
Cortical hormones
* Mineralocorticoids
* *Kidney*
* Glucocorticoids
* *Metab of fat, charbohydrates, protein*
28
Cushing's Sydrome
* results from *chronic exposure to excess corticosteroids,* particularly glucocorticoids.
* **Conditions causing CS:** _most common_ = iatrogenic adminstration of exogenous corticosteroids (e.g., prednisone)
* Excess circulation of glucocorticoids
* **Pituitary tumor 60%**
* increased Adrenocorticotropic hormone (ACTH)
* **Primary Adrenal neoplasm/hyperplasisa 25%**
* **Ectopic ACTH or CRH** (corticotropin-releasing hormone) 15%
* Pulmonary tumors
* Women \> Men
29
Iatrogenic
of or relating to illness caused by medical examination or treatment.
30
Cushing's Sydrome Diagnostic Tests
* 24 hour urine free cortisol
* Best for dx Cushing’s syndrome
* Day 1 collect second void and remaining voids
* Day 2 collect just AM void
* Normal: 10-100 mcg/24 hours
* Increased levels – Cushing’s
* Decreased levels – Addison’s
* **8 mg overnight dexamethasone** (for borderline levels) suppression test
* **Day 1** – **_8 am_** cortisol level
* Take **_8 mg_** dexamethasone at **_11 pm_**
* **Day 2** – Collect blood at _8 am_ for cortisol level
* *Pituitary Cushing’s 50% reduction of morning serum cortisol*
31
Medications for Cushing's Syndrome
* If patient fail surgical treatmen
* **Inhibit cortisol production** in the adrenal glands
* ***Ketoconazole***
* ***Metyrapone***
* ***Aminoglutethemide***
* ***Mitotane***
* Must identify the cause first:
* Pituitary Cushing’s
* Transsphenoidal surgery
* Irradiation
* Gamma Knife
* Adrenal Tumor
* Adrenalectomy - increased risk for adrenal crisis
* Ectopic
* Surgery/radiation
32
Adrenal Insufficiency
hypodisfunction of adrenal cortex
33
Adrenal Insufficency - Primary vs. Secondary cause
**Addison’s Disease**
* West – **autoimmune** causes -adrenal tissue destroyed by abs agains pt’s own adrenal cortex
* All three classes of adrenal corticosteroids are reduced (gluco-, mineral-corticoids, and androgens)
* Gradual destruction of the adrenal glan
* World wide
* **TB**
* Destruction of the Adrenal gland
**Secondary adrenal insufficiency**
* Lack of ACTH secretion (corticosteroids and androgens are deficient, but mineral corticosteroids rarely are)
* Alteration in any step of the hypothalamic-pituitary-adrenal axis
* Can be temporary or permanent
34
Secondary causes of Adrenal Insufficiency
* Iatrogenic (induced by physician)
* Abrupt withdrawal of exogenous adrenocorticotropic hormones (ATCH)… or
* Complications of cortisol therapy
* qCortisol therapy → ↓ATCH secretion by disrupting the natural feedback loop → acute adrenal insufficiency.
* Other secondary causes
* Metastatic carcinomas
* Lung
* Breast
* Pituitary infarct
* Surgery
* CNS Disturbances
* Basilar Skull Fracture
* Meningitis
35
Chronic Adrenal Insufficiency Treatment
Chronic Adrenal Insufficiency
* Hydrocortisone
* Usually 2/3 in AM
* 1/3 in PM
* Mimics the natural body
* Mineralocorticoid
* Fludrocortisone (Florinef)
36
Adrenal crisis (aka addisonian crisis or acute adrenal insufficiency)
* Rare – Life threatening emergency caused by insufficient adrencorticol hormone or a sudden sharp decrease in the hormones
* Dysfunction of the adrenal cortex
* Hypoadrenalism
* Hypocorticism
* Primary vs Secondary
* Primary – involves the adrenal gland
* Secondary – related to some other cause
* Hypothalmic-pituitary disease
37
Initial symptoms of Adrenal Crisis?
* Initially
* N/V/D
* Weakness
* Fatigue
* Anorexia
* Abdominal Pain
* Initial Symptoms
* Non-specific until linked with past history of AI or recent use of corticosteroid
* \> 20 mg hydrocortisone for 7 – 10 days
* Suppression of hypothalmic-pituitary-adrenal feedback
38
Signs of Adrenal Crisis
Severe Dehydration
* Weight Loss
* Orthostatic hypotension
Dehydration is related to nephrons inability to reabsorb sodium and water
39
Other S/S of Adrenal crisis
* Tachycardia
* Orthostatic HTN
* Headache
* EKG changes associated with ↑K+
* Hyperpigmentation
40
Lab findings of Adrenal Crisis
**Aldosterone Deficiency**
* Hyperkalemia
* \>5mEq/L
* Hyponatremia
* \<130mEq/L
* Hypovolemia
* Elevated BUN/CR
**Cortisol Deficiency (milder):**
* Hypoglycemia
* Decreased gastric motility
* Decreased vascular tone
* Hypercalcemia
prim & sec? = anemia and leukocytosis - eosonophils?
41
ATCH levels
**Elevated** -= primary adrenal insufficiency,
**norm/low** = secondary
42
Other Tests - Adrenal Insufficiency
CT of Head & CT of Adrenals
43
Adrenal Crisis Management Goals
* Administer needed Hormones
* Restore fluid and electrolyte balance
* Hormone Replacement
* Hydrocortisone
* 100 mg IV q 6 – 8 hours for 24 hours
* Glucocorticosteroids (prednisone & decadron) cause further loss of sodium….
* DO NOT USE
* Fluid Replacement
* Normal Saline
* Dextrose
* Vasopressors
* To use or not to use???
* Are not effective until the patient is adequately hydrated.
44
Pituitary Tumors
* Also called adenomas
* Hyperfunction
* Anterior Pituitary Gland
* May involve 1 or more hormones
45
Pituitary Tumor Classification
* Size
* Macroadenomas - \> 10 mm in diameter
* Microadenomas - \<10 mm in diameter
* Hormone Production
* Prolactin – 60%
* Growth Hormone – 20%
* ACTH – 10%
* Others – 10%
46
Prolactin Hypersecretion associated with Pituitary Tumors
* Decreased testosterone
* Loss of Libido; ED
* decreased sperm count
* Gynecomastia – rare galactorrhea
* Decreased Estradiol -
* Irregular menses
* Infertility
* Galctorrhea
* Ectopic Causes
* Dopamine antagonists
* Chronic Renal Failure
* Decreased clearance
* Neurogenic secretion
* Chest trauma, thoracotomy, herpes zoster
* Hypothyroidism
* Medications• Page 1062 Box 38-1
47
Growth Hormone (Acromegaly)
* Macroadenomas -\> Ha = headaches
* Facial Features
* Coarsening of features
* Increased size of nose, lips, and skin foldso
* Increase size of hands and feet
* Deepening voice
* Increase vertebral bodies -\> kyphosis
48
Diagnosis –Prolactin Hypersecretion
* Based on History
* Galactorrhea
* Irregular menstrual cycle
* Infertility
* Gonadal Dysfunction
* Prolactin Levels
* Normal – 20 ng/ml
* Medication - \<150 ng/ml
* Tumor - \>150 ng/ml
49
Diagnosis of GH Hypersecretion
Clinically obvious
Confirmed by GH levels
