Greater Splanchnic Nerve Flashcards

Trace the greater thoracic splanchnic nerve from its sympathetic origins to the celiac ganglia, including its course and visceral connections.

Card 1 of 24Question

What is the greater splanchnic nerve?

A paired thoracic splanchnic nerve carrying predominantly preganglionic sympathetic fibers toward abdominal prevertebral ganglia.

In This Section

1. What is the greater splanchnic nerve?

A paired thoracic splanchnic nerve carrying predominantly preganglionic sympathetic fibers toward abdominal prevertebral ganglia.

2. Which thoracic sympathetic ganglia typically contribute to the greater splanchnic nerve?

The fifth to ninth thoracic sympathetic ganglia (T5 to T9), with anatomical variation.

3. Which division of the autonomic nervous system is primarily represented in the greater splanchnic nerve?

The sympathetic division.

4. Where are the cell bodies of the preganglionic sympathetic neurons contributing to the greater splanchnic nerve?

In the intermediolateral cell column of the thoracic spinal cord.

5. Do the preganglionic fibers of the greater splanchnic nerve normally synapse in the thoracic sympathetic trunk?

No. They pass through the paravertebral sympathetic ganglia without synapsing.

6. Where is the greater splanchnic nerve formed?

In the posterior mediastinum from branches of the thoracic sympathetic trunk.

7. In which direction does the greater splanchnic nerve descend through the posterior mediastinum?

Inferomedially toward the diaphragm and upper abdominal prevertebral ganglia.

8. What is the relationship of the greater splanchnic nerve to the thoracic vertebral bodies?

It descends along their anterolateral aspects in the posterior mediastinum.

9. How does the greater splanchnic nerve usually enter the abdominal cavity?

By piercing the corresponding crus of the diaphragm.

10. Which prevertebral ganglia are the principal termination sites of the greater splanchnic nerve?

The celiac ganglia.

11. Where are the celiac ganglia located?

Near the origin of the celiac trunk on the upper abdominal aorta.

12. Which major abdominal autonomic plexus receives the greater splanchnic nerve?

The celiac plexus.

13. Which embryological division of the gastrointestinal tract receives sympathetic fibers primarily through the celiac plexus?

The foregut.

14. Which major abdominal organs receive sympathetic innervation through pathways associated with the greater splanchnic nerve?

The stomach, liver, gallbladder, pancreas, and proximal duodenum.

15. How do postganglionic sympathetic fibers from the celiac ganglia reach their target organs?

They follow branches of the celiac trunk within periarterial nerve plexuses.

16. What effect does sympathetic activity transmitted through the greater splanchnic nerve generally have on gastrointestinal motility?

It inhibits gastrointestinal motility and peristalsis.

17. How does sympathetic stimulation through the greater splanchnic pathway affect gastrointestinal blood vessels?

It generally causes vasoconstriction and reduces splanchnic blood flow.

18. Which visceral sensory fibers accompany the greater splanchnic nerve toward the spinal cord?

Visceral pain afferent fibers from upper abdominal organs.

19. Where are the cell bodies of visceral pain afferents traveling through the greater splanchnic nerve located?

In the dorsal root ganglia of the corresponding thoracic spinal nerves.

20. Do visceral pain afferent fibers synapse in the celiac ganglia?

No. They pass through the ganglia without synapsing.

21. How do greater splanchnic nerve fibers contribute to adrenal medullary innervation?

Some preganglionic sympathetic fibers pass through prevertebral ganglia and synapse directly on adrenal chromaffin cells.

22. Which other thoracic splanchnic nerves arise below the typical origins of the greater splanchnic nerve?

The lesser and least thoracic splanchnic nerves.

23. Why can interruption of the greater splanchnic nerve reduce upper abdominal visceral pain?

It interrupts visceral pain afferent pathways carrying signals toward thoracic spinal segments.

24. What surgical procedure may target the greater splanchnic nerve for severe upper abdominal visceral pain?

Thoracoscopic splanchnicectomy, sometimes used for refractory pancreatic cancer pain.