Gut book 7: Lymphatics & Autonomics of the Abdomen Flashcards
Abdominal parietal lymphatics
Composed of a chain of lumbar nodes and their lymphatic channels that ascend the aorta thereby forming lumbar trunks.
Afferents to the lumbar trunks
external and internal iliac trunks that bring lymph from the lower limb, pelvis, perineum, gluteal area and lower abdominal wall.
Lumbar nodes receive lymph primarily from
retroperitoneal structures: kidneys, ureters, suprarenal glands, lateral and posterior abdominal wall, and the abdominal surface of the diaphragm, as well as from the testes, ovaries, uterine tubes and superior portion of the uterus.
Note: the left lumbar trunk receives a portion of hte lymphatic drainage fo the inferior mesenteric nodal system as well as the INTESTINAL LYMPHATIC TRUNK 70%^ of the time.
Lumbar trunks join at
approximately LV1-2 and in 25% of the specimens form a dilatation, the cisterna chyli, located posterolaterally to the aorta under the right crus of the diaphragm.
The cysterna chyli is drained by
the thoracic duct, which passes through the aortic hiatus between the right crus and the aorta to end in the left jugulovenous angle.
Abdominal visceral lymphatics are composed of
a chain of mesenteric and celiac nodes and their lymphatic channels that receive lymph from the organs of digestion via specific organ lymph nodes and lymphatic channels.
Lymphatics draining visceral structures parallel the specific arterial supply of those viscera and therefore drain to nodes named for the three ventral unpaired arteries: celiac, superior and inferior mesenteric.
Inferior mesenteric nodes
Nodes located at the root of the inferior mesenteric artery
receive lymph from the rectum, sigmoid colon and descending colon via sigmoid and left colic nodes
major drainage of inferior mesenteric nodes is to superior mesenteric nodes; minor drainage is to the left lumbar trunk.
Superior mesenteric nodes
nodes located at the root of the mesentery
receive lymph from the transverse and ascending colon, ileum and jejunum via mesenteric, ileocolic, right colic and middle colic nodes as well as lymph from the inferior mesenteric nodes.
Major drainage of superior mesenteric nodes is to celiac nodes; minor drainage is to the intestinal trunk.
Celiac nodes
nodes clustered at the root of the celiac trunk
receive lymphatic channels from the liver, stomach, pancreas and spleen via hepatic, gastric and pancreaticosplenic nodes as well as lymph from the superior mesenteric nodes.
Celiac nodes drain to the intestinal lymph trunk.
Hepatic lymphatics
drain superiorly through the caval, esophageal and sternocostal hiatuses.
What receive drainage from the distal portion of the esophagus above the diaphragm.
gastric nodes located near the cardia
Intestinal lymph trunk
formed by efferent lymphatic channels of the celiac nodes joined by the minor drainage of the superior mesenteric nodes
Drains either to the cisterna chyli (30%) or to the left lumbar trunk (70%)
lymphogenous spread of cancer cells from the organs of digestion
will eventually spread to celiac nodes and from there to the cisterna chyli and ultimately through the thoracic duct to the venous system.
Abdominal sympathetic innervation originates… and travels
in thoracic and lumbar segments of the spinal cord and travels to collateral (pre-aortic) ganglia via thoracic and abdominal (lumbar),, splanchnic nerves.
Abdomominal parasympathetic innervation originates… and travels
in the brainstem (dorsal motor nucleus of the vagus) and in spinal cord segments S2,3,4 and travels to submucosal and myenteric ganglia via the vagus and pelvic splanchnic nerves, respectively.
What do abdominal parasympathetic and sympathetic systems contain?
visceral efferent and afferent fibers that form autonomic plexuses on the surface of arterial blood vessels.
Parasympathetic activity in the abdomen stimulates
glandular secretion and peristalsis and causes relaxation of sphincters
sympathetic activity in the abdomen does what?
constricts the sphincters, increases vasomotor tone, and decreases glandular secretion.
Parasympathetic afferents (GVA fibers) register..
hunger, nausea and distension, contribute to visceral reflexes and return to the CNS via the vagus nerve and along pelvic splanchnic nerves to sacral nerves and dorsal root ganglia at S2,3,4
Afferents that travel with the sympathetic system register…
acute pain from viscera and mesenteries and course to the CNS via splanchnic nerves, spinal nerves and dorsal root ganglia at T1-L2(3)
Abdominal sympathetic trunk
the thoracic sympathetic trunk continues into the abdomen by passing beneath the medial arcuate ligament.
lying superficial to the medial border of the psoas, it hugs the lateral surface of the vertebral bodies becoming more ventral as it descends.
Ganglia in the lumbar region are irregular, numbering 2-6
The lumbar sympathetic trunk receives…
white rami communicantes from L1, L2 and sometimes L3, although illustrations you may encounter include L4.
Abdominal aortic autonomic plexus subsidiary plexuses
autonomic fibers cover the anterior and lateral surfaces of the aorta forming an intricate abdominal aortic autonomic plexus divisible into: celiac plexus intermesenteric plexus superior hypogastric plexus inferior hypogastric plexus
Celiac plexus
from the root of the celiac artery to the superior mesenteric artery
intermesenteric plexus
between the aortic origins of the superior and inferior mesenteric arteries
superior hypogastric plexus
from the root of the inferior mesenteric artery to the sacrum below the aortic bifurcation anterior to LV4-SV1
inferior hypogastric plexuses of the pelvis
via the hypogastric nerves. The single superior hypogastri plexus bifurcates forming two hypogastric nerves which descend on either side of the rectum to join the inferior hypogastric plexuses located there.
What do the abdominal autonomic plexuses contain?
preganglionic sympathetic fibers (from splanchnic nn),
postganglionicrs (from ganglia associated with the plexuses)
preganglionic parasympathetic fibers (from the vagus n. and pelvic splanchnic nn) and
sympathetic prevertebral ganglia, i.e. celiac, aorticorenal, superior and inferior mesenteric ganglia, which contain postganglionic sympathetic cell bodies.
how do postganglionic sympathetic and preganglionic parasympathetic fibers travel from the autnomic abdominal plexuses?
to the derivatives of the foregut, midgut and hindgut via subsidiary plexuses located onthe surface of arterial blood vessels, i.e. celiac plexus, left gastric plexus, splenic plexus, hepatic plexus, superior & inferior mesenteric plexuses, renal plexus, and hypogastric plexuses.
