Hypothalamus & Pituitary - Quiz 2 Flashcards Preview

Summer 2020 - Physiology 2 - Endocrine > Hypothalamus & Pituitary - Quiz 2 > Flashcards

Flashcards in Hypothalamus & Pituitary - Quiz 2 Deck (44)
Loading flashcards...
1
Q

What is the Hypothalamic Pituitary Axis?

A

Unit formed by hypothalamus & pituitary responsible for brain-endocrine interactions and control Gonads, Thyroid, and Adrenal glands

2
Q

Which endocrine gland is considered the Master Gland?

A

Pituitary

3
Q

How does the Hypothalamus work?

A

Coordinating Center

Gets signals from cortical inputs, autonomic function, environment, and endocrine feedback then delivers precise signals to the pituitary to release hormones influencing other endocrine systems

4
Q

Where can the Pituitary Gland be found?

A

In the Sella tursica of the Sphenoid Bone

5
Q

How is the Pituitary Gland divided?

A
  • Anterior Pituitary (Adenohypophysis)
  • Pars Intermedius
  • Pars tubularis
  • Neurohypophysis - Posterior Pituitary
6
Q

Which part of the Pituitary Gland is highly vascular and does not secrete any hormones?

A

Pars Tuburalis

7
Q

Which is the largest part of the Pituitary Gland?

A

Anterior Pituitary / Adenohypophysis

8
Q

Which part of Pituitary Gland is present only up until Fetal Development?

A

Pars Intermedius

9
Q

What makes the Anterior and Posterior Pituitary distinct?

A

Different connections to hypothalamus

Contain different cell types

Secrete different hormones

10
Q

What are the main functions of the Hypothalmus?

A
  1. Produce Releasing and Inhibiting hormones that influence Anterior Pituitary
  2. Produces Oxytocin & ADH and stored in Posterior Pituitary
  3. Oversees ANS and helps stimulate Adrenal Medulla
11
Q

How does the Anterior Pituitary connect to the Hypothalamus?

A

Portal Venous Network

12
Q

Which hormones and glands does the Anterior Pituitary regulate?

A

FLATPIG

  • *F** ollicle Stimulating Hormone - gonads
  • *L** uteinizing Hormone - Ovaries
  • *A** Adrenocorticotropic Hormone (ACTH)
  • *T** hyroid Stimulating Hormone
  • *P** rolactin (PRL) - mammary
  • *I** gnored - Melanocyte Stimulating Hormone
  • *G** rowth Hormone - Somatotropic

13
Q

What are the different cell types of the Anterior Pituitary

A

Somatotropes - most abundant (30-40%)

Corticoctropes (20%)

Thyrotropes (3-5%)

Gonadotropes (3-5%)

Lactotropes (3-5%)

14
Q

What is the Posterior Pituitary made of?

A

Collection of Axonal Projections from the Hypothalamus

15
Q

What are the functions of the Posterior Pituitary?

A

Receives Oyxtocin & ADH made in the Hypothalamus and secretes these hormones

Regulates Uterine Contraction & Water Balance

16
Q

What supplies blood to the Hypothalamus?

A

Superior Hypophyseal Artery

17
Q

What supplies blood to the Posterior Pituitary?

A

Inferior Hypophyseal Artery

18
Q

How is ADH & Oxytocin transported from the Hypothalamus to the Posterior Pituitary?

A

Via nerve fibers in the Supraoptic Nucleus & Paraventricular Nucleus

19
Q

What does Vasopressin do?

A

↑Collecting Duct Permeability

↑Water Reabsorption

↑ECF Volume

↑Urine Osmolality

↓Plasma Osmolality

Vasoconstriction

20
Q

What does the V1 & V2 Vasopressin receptors do?

A

V1: Pressor Effect

V2: ADH effect

21
Q

What stimulates Vasopressin/ADH release?

A
  • Plasma Osmolality > 290
  • Decreased ECF Volume
  • Increased Sodium
  • Low BP
  • Angiotensin II
  • Nicotine
  • Stress & Pain
  • Positive Pressure Ventilation
22
Q

Alcohol, Increased ECF, and Decreased Plasma Osmolality causes what?

A

Depressed release of Vasopressin/ADH

23
Q

What conditions are due to ADH disturbances?

A

Diabetes Insipidus & SIADH

24
Q

How does Diabetes Insipidus happen?

A

Inability to release ADH causing ADH Deficiency

Can be Neurogenic (most common) or Nephrogenic

25
Q

What are the symptoms of Diabetes Insipidus?

A

Pee Alot

Extreme Thirst

Hyperosmotic Plasma

HypoOsmotic Urine

26
Q

How should patients w/ Diabetes Insipidus be managed?

A

Water Intake

Limit Sodium

Give DDAVP

27
Q

What can cause Nephrogenic Diabetes Insipidus?

A

Chronic Renal Disease

Lithium Toxicity

Hypercalcemia

Hypokalemia

Tubulointerstitial Disease

28
Q

What are some Anesthetic considerations for a pt w/ Hypernatremia r/t DI?

A

Increased MAC

Decreased CO = decreased uptake

Hypovolemia = decreased IV dose

29
Q

What are symptoms of Hypernatremia?

A

Restlessness

Lethargy

Hyperreflexia

Seizures

Coma

Death

CORRECT SLOWLY

30
Q

An overload of Vasopressin/ADH causes this type of ADH Disturbance?

A

Syndrome of Inappropriate ADH

31
Q

What can cause SIADH?

A

CNS Disorders

Head Trauma

Lung Squamous Cell Carcinoma

Pulmonary Infection

Pituitary Surgery

32
Q

What are the signs and symptoms of SIADH?

A

Water Intoxication

Hyponatremia

Concentrated Urine

Dilute Plasma

Brain Edema

Lethargy, Seizure, Coma

33
Q

How should a patient w/ SIADH be managed?

A

Treat underlying cause

Fluid Restriction

Demeclocycline

3% Hypertonic Saline

Lasix

CORRECT SLOWLY & Monitor Na q1-2 hrs

34
Q

At what levels of sodium should postponing elective surgeries be considered?

A

Sodium < 130 or > 150

35
Q

What can happen if Hyponatremia is treated too aggressively?

A

Central Pontine Myelinolysis

Spastic Quadriplegia

Pseudobulbar Palsy

Encephalopathy

Coma

36
Q

Where is Oxytocin secreted from?

A

Paraventricular Nucleus

37
Q

How does Oxytocin increase Lactation?

A

Positive Feedback

Oxytocin –> Lactation –> Baby Eats –> Activates Afferent Fibers –> Signals Paraventricular Nuclei to release more Oxytocin

38
Q

Beside lactation, what else is Oxytocin/Pitocin used for?

A

Organize Labor by increasing Uterine Contraction & Decreasing Blood loss after birth

39
Q

What are some complications associated w/ Pitocin?

A

Fetal Distress d/t hyperstimulation

Uterine Tetany

Maternal Water Intoxication

Hypertension

Tachycardia

N/V

Seizures

40
Q

What can happen if the Pituitary grows too big or if there are tumors on it?

A

Compression of Optic Chiasm causing vision problems

41
Q

What should you expect for a patient having Pituitary surgery and has too much Growth Hormone?

A

Acromegaly making it difficult to mask & intubate
(Use smaller ETT)

Glucose Intolerance

HTN

Cardiomyopathy

LVH

42
Q

What is to be expected w/ a patient who has too much ACTH?

A

Cushing’s Disease & Difficult Airway

43
Q

What should be given to a patient w/ Panhypopituitarism?

A

Hormone replacement:

DDAVP

Cortisol

Levothyroxine

44
Q

During Pituitary surgery, when would you suspect IntraOp Diabetes Insipidus and how would you treat?

A

High uring output w/ < 1.005 specific gravity

DDAVP 0.5 - 1 mcg

Fluids