The esophagus is located in the posterior mediastinum. It lies medial in front of the spinal column until the tracheal bifurcation (T4), after which it moves to the right side, to make room for the heart. Lastly, it crosses the diaphragm to the left of the median line. At the level of T7–T8, the aorta squeezes in between the spinal column and the esophagus. The abdominal part is only about 2 cm long.

trachea

left main bronchus

mediastinal pleura

pericardium

spinal column

aorta

right lung (in the area of the esophageal hiatus)

vagus nerve, right and left

peritoneum in the front

liver

crus to the left of the diaphragm

left side: left triangular ligament

right side: lesser omentum

T10 and T11

organ pressure

turgor

mediastinal connective tissue

phrenoesophageal ligament (ring-shaped disk in the hiatus).

The esophagus remains mobile in the lengthwise direction.

inferior thyroid artery

small branches from the subclavian/communal carotid/vertebral arteries, etc.

inferior thyroid vein (from the superior vena cava)

bronchial arteries

aorta

azygos/hemiazygos/accessory hemiazygos vein (from the superior vena cava)

left gastric artery

inferior phrenic artery

celiac trunk

left gastric vein (main drainage) to the portal vein

deep cervical cord (internal jugular vein–parotid gland–clavicle)

intercostal, thoracic nodes near the spinal column

paratracheal nodes along the recurrent laryngeal nerve

tracheobronchial nodes

These nodes all drain into the right/thoracic lymphatic duct.

nodes around the celiac trunk (cisterna chili—thoracic duct)

sympathetic nervous system from T4 to T6

further path of sympathetic innervation: pharyngeal plexus–superior cervical/stellate ganglion–greater splanchnic nerve–celiac plexus

vagus nerves accompany the esophagus into the abdomen

Division into:

cardia (stomach entrance)

fundus (cranial region, filled with air)

body

antrum

pylorus

greater curvature

lesser curvature

ICS, intercostal space.

Cardia and pylorus are relatively fixed points; in between, great variability is possible depending on the state of fullness.

diaphragm

indirect: pleura and left lung, pericardium and heart

ribs 5–8 and costal cartilage 9 on the left

liver

celiac trunk and plexus

omental bursa

left crus of the diaphragm

left adrenal gland

left kidney

pancreas

transverse colon

transverse mesocolon

left colic flexure

duodenum (horizontal and ascending part)

duodenojejunal flexure and start of the jejunum

spleen

organ pressure

turgor

gastrophrenic ligament

lesser omentum

greater omentum

gastrocolic ligament

gastrolienal ligament

left phrenicocolic ligament

Fig. 7.1 Upper abdominal organs, transverse section.

Fig. 7.3 Attachments of the stomach.

right gastric artery (from proper hepatic artery)

left gastric artery (from celiac trunk, anastomosed with the right gastric artery)

right gastro-omental artery (gastroduodenal artery)

left gastro-omental artery (splenic artery—celiac trunk)

gastroduodenal artery (common hepatic artery—celiac trunk)

Portal vein.

paracardial lymph nodes

pancreatic lymph nodes

splenic nodes

celiac nodes—thoracic duct (main drainage)

sympathetic nervous system from T6 to T9 via the greater and lesser splanchnic nerves

further path of sympathetic innervation runs to the celiac and superior mesenteric ganglion

vagus nerve

Maximal time: 7–9a.m.

Minimal time: 7–9p.m.

The esophagus has lengthwise mobility. During movements of the head and neck, it must be able to adjust its length.

To transport food, peristaltic waves run through the esophagus during the act of swallowing.

The stomach shows mobility in three planes: frontal, sagittal, and transverse.

Frontal Plane

During inhalation, the diaphragm guides the lateral parts of the fundus of the stomach inferomedially. The distance between the lesser and greater curvature decreases, as does the distance between the fundus and antrum. Looked at from the front, the stomach rotates in a clockwise direction.

Sagittal Plane

In this plane, the stomach performs a tilt with the cranial parts of the fundus in an anterior direction, accompanied by a simultaneous shift posteriorly in the antral area. The frontotransverse axis of movement runs roughly through the center of the stomach.

Transverse Plane

The stomach performs a rightward rotation along a frontosagittal axis through the inferior part of the esophagus.

The motions of motility correspond in direction and axis to those of mobility.

The relief structure of the stomach wall serves as a “slide” for the chyme in the direction of the pylorus. The proximal stomach acts as food storage and is marked by continuous tension in the walls.

The distal stomach has the task of mixing, homogenizing, and emulsifying the food. For this purpose, peristaltic waves run from a central pacemaker through the distal stomach. A distension in the stomach stimulates these waves; a distension in the small intestine inhibits the activity of the distal stomach (enterogastric reflex).

The pylorus does not close so tightly that fluids are unable to pass. It relaxes synchronously with each contractile wave of the distal stomach, but only far enough that small food particles can still pass while the large parts are thrown back.

grinding up solid food, emulsification of fats, predigestion of proteins

secretion of gastric juice

Mucus is secreted by the epithelial cells on the surface of the stomach, the side cells of the fundic glands, and the cardiac and pyloric glands.

Bicarbonate is secreted by the epithelial cells in the stomach mucosa.

Both components of gastric juice serve to protect the stomach walls from hydrochloric acid (HCl). An H⁺ gradient exists across the mucosa, from strongly acid on the lumen side to slightly alkaline on the epithelium side (effect of bicarbonate).

Pepsinogen is secreted by the chief cells of the fundic and body glands. At a pH < 3, it is activated into pepsin and cleaves proteins.

Hydrochloric acid is secreted by the parietal cells in the fundic glands.

The intrinsic factor is necessary for the absorption of vitamin B₁₂ in the small intestine.

The secretion of gastric juice has several trigger mechanisms.

The secretion of gastric juice is stimulated via the vagus nerve by smell, taste, and glucose deficiency in the brain.

Distension of the stomach, amino acids (especially tryptophan and phenylalanine), and Ca²⁺ ions increase the secretion of gastric juice.

This is stimulation by the voiding of chyme into the duodenum. The secretion of gastric juice is inhibited by a strongly acid pH balance in the stomach which inhibits the release of gastrin; this, in turn, inhibits the secretion of HCl in the parietal cells.

Gastrin is secreted by the antral glands (two-thirds) and the duodenal mucosa (one-third).

Release Stimulation

presence of peptides or certain amino acids

vagal efferents

high catecholamine concentration in the plasma

Release Inhibition

The pH of gastric juice is < 3.

Functions

stimulates HCl secretion in the parietal cells

increases strength and frequency of antral peristalsis

promotes epithelial growth in the stomach and duodenum

stimulates the pancreatic acini, bile secretion, and gallbladder contraction

Cholecystokinin (CCK) is secreted in the duodenal and jejunal epithelia.

Release Stimulation

Presence of free fatty acids, peptides, aromatic amino acids, or glucose in the duodenal lumen.

Release Inhibition

Trypsin in the intestinal lumen (protein-cleaving enzyme from the pancreas).

Functions

stimulates the acinar cells of the pancreas (neutral chloride-rich juice with proenzymes)

stimulates the secretion of alkaline pancreatic juice rich in bicarbonate

releases all pancreatic hormones

promotes pancreatic growth

stimulates the chief cells of the stomach (⇒ pepsinogen ↑)

inhibits HCl secretion

strong stimulator of gallbladder contraction, opens the sphincter of Oddi

satiety hormone

Fig. 7.5 Voiding times from ingestion.

Secretin is secreted in the duodenal and jejunal epithelium.

Release Stimulation

Acid chyme.

Functions

stimulates the secretion of alkaline pancreatic juice rich in bicarbonate

alkalizes the bile in the bile duct system

inhibits the resorption of water and salt in the gallbladder

slows down the emptying of the stomach by inhibiting the stomach muscles

antitrophic effect on the gastric mucosa

Prolapse of parts of the stomach or of the entire stomach (possibly even of other organs) through the esophageal hiatus into the thorax.

Sliding Hernia

Movement of the cardia and fundus into the rear mediastinum, with the pointed angle of His being lifted.

Frequently asymptomatic. About 25% of patients develop reflux symptoms; reflux esophagitis is possible (5% of cases).

Paraesophageal Hernia or Rolling Hernia

Protrusion of parts of the fundus into the thorax (past the esophagus and the cardia, which is fixed in its normal location), with a pointed angle of His.

The sphincter continues functioning and reflux is unlikely to occur. Cardinal symptoms are pain in the epigastrium and iron deficiency anemia.

Hybrid forms between the two are possible.

Functional Hernia according to Barral

In cases with similar symptoms, the radiological signs of a hiatus hernia are absent. Such conditions can be caused by a spasm in the gastroesophageal transition or nonphysiologic tissue pulls in the peritoneum, ligaments, or fascia.

physiologic pressure conditions in the abdomen and thorax

causes for pathologic changes: pregnancy, cough, obstipation with impaired defecation

soft anatomic surroundings that are free from nonphysiologic tissue pulls

causes for pathologic changes: surgery or effects of inflammation

physiologic lengthwise tension in the esophagus

causes for pathologic changes: kyphotic posture or inflammation

functional diaphragm tension and position

for healthy sphincter function, the angle of His must be pointed

normotonic muscle tension at the gastroesophageal transition

Clinical. Roughly 95% of all reflux patients have a hiatus hernia; by contrast, only about 5% of patients with hiatus hernia have reflux disease.