Gastroenterology and Neurology CP

Question 1

what are the layers of the esophagus and what muscle makes up the upper two thirds

Answer 1

muscular tube with an internal circular layer and external longitudinal layer, the upper two thirds of the esophagus is a combination of both smooth and skeletal muscle

Question 2

What are the three regions of the esophagus

Answer 2

Cervical part

Thoracic part (between T1 and the esophageal hiatus of the thoracic diaphragm)

Abdominal part

Question 3

What are the 4 constrictions of the Esophagus

Answer 3

At the cricopharyngeus Muscle (called upper esophageal sphincter)

at aortic arch

At left bronchus

At the Esophageal hiatus of the thoracic diphragm (called the lower esophageal sphincter)

Question 4

What is the cranial Nerve associated with the thorax and what are the 5 branches of it

Answer 4

Vagus Nerve

• Left recurrent laryngeal N
• Pulmonary Branches
• Inferior cardiac branch
• Anterior Vagal trunk (left vagus N)
• Posterior Vagal trunk (right Vagus N)

Question 5

What are the Cervical Spinal Nerves associated with the Thorax

Answer 5

Phrenic N (anterior Rami of C3,4,5)

travels along the space between the Mediastinal Parietal Pleura and Fibrous Pericardium

innervates the Thoracic Diaphragm

Question 6

What are the Typical Intercostal nerves and their 5 branches

Answer 6

3rd-6th

Rami Communciates (connect intercostal N to ipsilateral sympathetic trunk)

Collateral Branches (assist in innervating the intercostal M and travels on the superior edge of the rib inferior to the intercostal space

Lateral Cutaneous Branch ( Become anterior and posterior branches that supply the skin of the thoracic wall, T4-6 supply the breast)

Anterior Cutaneous branches (supply anterior aspect of the thoracic wall, T4-6 supply the breast)

Muscular branches (supply the intercostal M, subcostal M, and transverse thoracis M)

Question 7

What are the Atypical intercostal N

Answer 7

1st, 2nd, 7th-11th

Question 8

Atypical intercostal Nerve Characteristics: 1st

Answer 8

the 1st intercostal N has no cutaneous branches and majority of the superior portion joins the brachial plexus

Question 9

Atypical intercostal Nerve Characteristics: 2nd

Answer 9

Majority travels in the costal groove as a typical intercostal N with small part joining with the brachial plexus

the lateral cutaneous branch supplies skin and subcutaneous tissue of the axilla and is called: intercostobrachial N

Question 10

Atypical intercostal Nerve Characteristics: 7-11

Answer 10

Begin as intercostal N but as they travel anteriorly they cease to exist between ribs and transition over the abdomen to become thoracoabdominal N

Question 11

characteristics of the Presynaptic Fibers of the sympathetic division

Answer 11

short

Cell bodies exist in the lateral horn of the spinal Cord

Always travels in the anterior root

always travels into the anterior ramus

quickly exit anterior ramus and enters the paravertebral ganglia

Question 12

What are the three synaptic options for the Presynaptic fibers in the sympathetic division

Answer 12

1) can enter paravertebral ganglion and synapse onto a postsynaptic neuron in the same spinal level
2) can enter the paravertebral ganglion ascend or descend to synapse on a postsynaptic neuron in a different spinal level
3) can enter the paravertebral ganglion and exit without synapsing and contiune on through an abdominopelvic splanchnic nerve on their way to a postsynaptic neuron in prevertebral ganglion

Question 13

where do the cell bodies exist for postsynaptic fibers of the sympathetic division

Answer 13

Paravertebral ganglia: linked vertically to form the sympathetic trunks on either side of the vertebral column, three ganglia also exist in the cervical, lumbar, and pelvic regions

Prevertebral ganglia (ganglia and corresponding plexuses surronding the main unpaired branches of the abdominal arch

• Celiac ganglion
• Superior mesenteric ganglion
• aorticorenal ganglion
• inferior mesenteric ganglion

Question 14

what is the location of the sypmathetic division in the spinal cord

Answer 14

THoracolumbar T1-L2

Question 15

what are the three main nerves for the sympathetic presence in the thorax

Answer 15

Thoracic SYmpathetic trunk

Cardiopulmonary splanchnic N

Abdominopelvic Nerves

Question 16

What two nerves make uup the Cardiopulmonary splanchnic Nerves

Answer 16

Cardiac Splanchnic N (presynaptic cell bodies are in spinal cord levels T1-5 or 6 then synapse on the sympathetic trunk and then send fibers to the superficial and deep plexuses

Pulmonary splanchnic N (presynaptic cell bodies in the lateral horn of the spinal cord at the levels T2-3 synapse on thoracic sympathetic trunk then travel to the pulmonary plexus

Question 17

What three nerves make up the Abdominopelvic splanchnic nerves

Answer 17

Greater Splanchnic Nerve (T5-9/10) sends fibers to the esophageal plexus and to the celiac ganglion in the abdomen which feeds to the celiac plexus

Lesser splanchnic Nerve (T10 and T11) send fibers to the Celiac and superior mesenteric ganglion in the abdomen that feeds into the superior mesenteric lexus

Least Splanchnic Nerve (T12) sends fibers to the aorticorenal ganglion in the abdomen

Question 18

What are the characteristics of the presynaptic fibers of the parasympathetic Nervous system

Answer 18

Craniosacral, CN III, VII, IX, and X, S2-4

Nuclei in brainstem and sacral spinal levels

fibers really long

sacral fibers exit as Pelvic splanchnic nerves

Question 19

what are the 4 specific cranial ganglia for parasympathetics and where are the intrinsic parasympathetic ganglia

Answer 19

Ciliary Ganglion
Pterygopalatine ganglion
Submandibular ganglion
Otic ganglion

Intrinsic parasympathetic ganglia: postsynaptic parasympathetic cell bodies located in the walls of target organs)

Question 20

what are the 5 branches of the parasympathetic presence in the thorax and what nerve do they all come off

Answer 20

Vagus N these branches all come from

1) superior Cardiac branch (originates in the neck and descends through the superior thoracic aperature, and with the cardiac splanchnic Ns forms the cardiac plexus)
2) Middle cardiac branch (originates in the neck and descends through the superior thoracic aperature and with the cardiac splanchnic Ns to form the cardiac plexus
3) inferior Cardiac Branch (originates in the thorax and with the cardiac splanchnic N forms the cardiac plexus
4) Pulmonary branches (originates in the thorax and with the pulmonary splanchnic N forms the pulmonary plexus)
5) Esophageal branches (after producing the pulmonary branches the Vagus nerve becomes indistinguishable from the esophageal plexus that covers the inferior 2/3 of the esophagus

Question 21

WHat are the 4 thoracic Autonomic plexus

Answer 21

Pulmonary plexus

Cardiac Plexus

Aortic Plexus

Esophageal Plexus

Question 22

Input, innervation and function of the: Pulmonary Plexus

Answer 22

input: sympathetic-Pulmonary splanchnic Ns
Parasympathetics-pulmonary branch of Vagus N

innervates: lungs, bronchi and pleura

function:
-sympathetic: bronchodilator of bronchi and bronchioles, inhibitor of glands, vasoconstrictor of pulmonary vessels and visceral sensory from lungs, bronchi and pleurae

-Parasympathetics: bronchoconstrictor, secretomotor of glands, vasodilator to pulmonary vessels, pressure sensory from pulmonary A, and chemoreceptor from pulmonary V, sensory to bronchial muucosa (cough reflex), reflexive from the interalveolar connective tissue

Question 23

Input, innervation and function of the: Cardiac Plexus

Answer 23

input: sympathetic-Cardiac splanchnic N
parasympathetic- superior, middle, inferior cardiac branches

Function:
-Sympatetic, innervate the Nodal tissue to increase heart rate, and the force of heart contraction, vasomotor of the pericardium

-Parasympathetics, innervate decreases heart rate, reduces force of contraction, and vasoconstricts the coronary arteries

Superficial cardiac plexus covers the anterior surface of the heart

Deep Cardiac plexus exist anterior to the bifurcation of the trachea, posterior to the aortic arch, superior to the bifurcation of the pulmonary trunk

Question 24

Input, innervation and function of the: Esophageal plexus

Answer 24

input: sympathetic-Greater splanchnic N and aortic plexus
- parasympathetic: Esophageal branches of vagus N

Function: sympathetic-inhibit peristalsis and esophageal glands
parasympathetics: stimulate peristalsis and esophageal glands