Lumbar Plexus and Pain Flashcards
Locations of parasympathetic pre-ganglionic cell bodies
CN III, VII, IX, and X
Sacral cord (S2-4)
Location of preganglionic parasympathetic cell bodies for vagus nerve
Dorsal motor nucleus
Location of parasympathetic postganglionic cell bodies relevant to the abdomen
Wall of the organ (terminal)
Parasympathetic NTs and receptors
ACh - pre and post synaptic
Nicotinic receptor
Muscarinic receptor
Location of sympathetic preganglionic cell bodies
Intermediolateral cell column, T1-L2
[aka lateral horn]
Location of sympathetic postganglionic cell bodies
Superior cervical ganglion
Sympathetic chain ganglion
Prevertebral ganglion (celiac, superior mesenteric, inferior mesenteric)
Sympathetic NTs and receptors
ACh - pre-ganglionic
NE - post-ganglionic to alpha and beta receptors
Sympathetics supplying parietal GI structures
Abdominal body wall: T7-T11
General Sympathetics supplying visceral GI structures
Body wall abdominal viscera = T7-T11
Which sympathetics supply viscera of stomach, liver, gallbladder, pancreas?
T6-T9
Which sympathetics supply viscera of appendix and colon?
T10, T11
Which sympathetics supply viscera of small bowel?
T7-T10
Which sympathetics supply visceral pelvic and lower limb structures
T12-L2(3)
Trace pathway of presynaptic sympathetic neurons, which all follow the same course from CNS to sympathetic trunk
Cell body in presynaptic neuron of lateral horn (T1-L2/3)
Leaves via anterior root of spinal n., becoming mixed spinal n
Fibers exit spinal nerves to autonomic paravertebral ganglion via white rami communicans to sympathetic trunk
T/F: paravertebral ganglia run the entire length of the vertebral column
True
4 options for presynaptic fibers entering sympathetic trunks
Ascend to higher level to synapse
Descend to lower level to synapse
Synapse at level of entry
Traverse the trunk without synapsing to become part of abdominopelvic splanchnic n. or for innervation of the suprarenal glands
Postsynaptic fibers of the sympathetic trunks exit at level of cell body to supply the body wall and limbs via _____ nerves in _____ rami communicantes
Spinal; gray
Postsynaptic sympathetic nerves travel to body wall and limbs. What are their 3 main functions?
Vasomotion (typically vasoconstriction)
Sudomotion (sweating)
Pilomotion (goosebumps)
Sympathetic innervation to the lower limbs has presynaptic fibers take descent option, travelling on nerves or vessels.
Sympathetic innervation to upper limbs has presynaptic fibers take ascent option, travelling on brachial plexus or blood vessels like the subclavian.
Sympathetic innervation to the head has presynaptic fibers take ascent option where they synapse with superior cervical ganglion, travelling with the carotids.
Describe sypathetic innervation to the abdomen
4th option! Presynaptic fibers pass through sympathetic trunk without synapsing to enter an abdominopelvic splanchnic nerve, which they travel with to prevertebral ganglion like celiac, superior mesenteric, or inferior mesenteric
T/F: abdominopelvic splanchnic nn pierce the diaphragm
True
What do sympathetic fibers do once they have joined up with abdominopelvic splanchnics and synapsed at prevertebral ganglion?
Hop on periarterial plexus to their intended abdominopelvic viscera
Abdominopelvic splancnic nerves include greater, lesser and least. What are their respective spinal levels?
Greater = T5-9
Lesser = T10,11
Least = T12
Visceral branches of sympthetic trunks:
Splanchnic nn arise as _____ branches of the trunks
Cardiopulm splanchnic nn convey _____ fibers to thoracic viscera and synapse in ____ ganglia
Abdominopelvic splanchnic nn convey ____ fibers to innervate the abdominal and pelvic viscera and synapse in _____ ganglia
Medial
Postsynaptic; paravertebral
Presynaptic; prevertebral
Cell bodies of sympathetic postsynaptic fibers are found in what 2 places?
Paravertebral ganglia of sympathetic trunks - fibers distributed to all parts of body EXCEPT abdominopelvic viscera (pass thru but do not synapse)
Prevertebral ganglia of paraaortic plexus; clustered around roots of major branches, fibers distributed to abdominopelvic viscera
One exception to the normal path taken by abdominal sympathetics is innervation of the suprarenal glands. What path do autonomics to the suprarenals follow?
The same path as abdominopelvic splanchnics until the prevertebral ganglia - where they will bypass the ganglia without synapsing! They synapse directly on secretory cells of the medulla which act as neurons
Sympathetic nerves have short presynaptic fibers and long postsynaptic fibers
Parasympathetic nerves have _______ presynaptic fibers that synapse on intrinsic ganglia such as the _______ plexus of visceral organs
Very long; myenteric
Parasympathetic presynaptic neuron fibers are transmitted only via which 2 pathways? Which one is dominant?
Cranial outflow = CN III, VII, IX, or X = dominant (extends to left colic flexure of gut)
Sacral outflow = S2-S4
What is the difference between postsynaptic ganglia in the trunk vs. the head?
In the trunk, ganglia are widely scattered, irregularly spaced, microscopic, and usually located in/on effector organ
In the head there are 4 discrete ganglia: ciliary, otic, pterygopalatine, submandibular
T/F: parasympathetic nerves travel with spinal nerves and their peripheral branches
False, this is never the case. Parasympathetics usually travel with vagus n.
Functions of sympathetics in GI tract
Constriction of blood vessels of skin and GI tract (diverting blood to skeletal muscle)
Decreases peristalsis, constricts sphincters
Stimulates suprarenal galnds to release adrenaline
Vasomotion, sudomotion, pilomotion
Functions of parasympathetics in the GI tract
Stimulates peristalsis
Inhibits sphincters, stimulates contraction of bladder and rectum
Primary stimulator of GI tract
Active in elimination
A “splanchnic nerve” is made up of what 2 nerve components?
Visceral afferent (sensory) fiber - receptors for pain and reflexes
Visceral motor (autonomic) fiber - smooth muscle, glands, etc.
Visceral afferent fibers travel with sympathetics or parasympathetics?
Both! 80% of fibers in vagus are afferents, 20% of fibers in splanchnic nn are afferent
Physiologic receptors, such as those detecting O2 saturation, travel with parasympathetics or sympathetics?
Parasympathetics (vagus or pelvic splanchnics)
Pain travels with sympathetics or parasympathetics?
Sympathetics, EXCEPT below the pelvic pain line (distal to middle of sigmoid colon)- where it travels with parasympathetics
Acute vs. chronic vs. subacute abdomen
Acute = less than 3 days duration
Chronic = greater than 3 weeks duration
Subacute = 3 days - 3 weeks
Pathologies of abdomen that cause pain
Inflammation Ischemia Stretching Obstruction Trauma Functional disease (IBS)
2 types of abdominal pain
Visceral - diffuse, poorly localized, often referred to somatic regions, injury to internal organs and tissues that support them
Somatic - well localized, caused by injury to skin, muscles, joint, bone, and CT
Parietal pain, in contrast to visceral pain, can be localize to the ______ superficial to the site of painful stimulus
Visceral pain that progresses can lead to parietal pain
Dermatome
Visceral pain can be localized by the sensory cortex to an approximate spinal cord level determined by the embryologic origin of the organ involved. Where does pain localize from foregut vs midgut vs hindgut?
Foregut (stomach, duodenum,biliary tract) = epigastric pain
Midgut (small bowel, appendix, cecum) = periumbilical pain
Hindgut (most of colon, including sigmoid) = suprapubic or hypogastric pain
Visceral pain travels with what sympathetics for:
Liver Stomach Pancreas Spleen Small intestine Kidneys Cecum Ascending colon Transverse colon Descending colon Sigmoid colon Rectum/anus
Liver = T6-9 Stomach = T6-9 Pancreas = T6-9 Spleen = T6-8 Small intestine = T8-10 Kidneys = T10-L1 Cecum = T10 Ascending colon = T10 Transverse colon = T11 Descending colon = T12-L1 Sigmoid colon = L2(3) Rectum/anus = S2-4
Esophagitis
Peptic ulcer
Perforated ulcer
Pancreatitis
The above would refer pain to what embryologic origin?
Foregut
Early appendicitis
Mesenteric adenitis
Meckel’s diverticulitis
Lymphomase
The above would be referred to what embryologic origin
Midgut
Testicular torsion
Urinary retention
Cystitis
Placental abruption
The above would refer pain to what embryologic origin?
Hindgut
Intermittent cramp like pain caused by obstruction of hollow muscular viscus
Colicky pain
Pain associated with gastric ulcer
Foregut visceral pain
Worse on eating, patient tends to avoid meals
What condition might be indicated by the following?
Foregut chronic visceral pain
Sudden severe pain spreading all over abdomen
Signs of generalized peritonitis
Perforated gastric ulcer
What condition might be indicated by the following?
foregut visceral pain Somatic pain in RUQ Referred pain to right shoulder Nausea/vomiting Fever Tender RUQ Positive Murphy’s sign
Acute cholecystitis
What condition might be indicated by the following?
Midgut visceral pain Somatic pain in RLQ N/V Fever Tender RLQ
Acute appendicitis
What condition might be indicated by the following?
Midgut visceral colicky pain Vomiting No flatus or bowel action Possible dehydration Distended soft abdomen, nontender Increased bowel sounds Hx of abdominal surgery
Adhesive SBO
What condition might be indicated by the following?
sudden onset severe colicky pain from loin to groin Severe back pain Patient writhing or pacing about Possible hematuria Afebrile Soft abdomen CVA tenderness
Passage of kidney stone
What condition might be indicated by the following?
Older age Weight loss Hindgut visceral colicky pain No flatus or feces Distended abdomen Increased bowel sounds Mass in LLQ
Obstructing cancer of descending colon
What condition might be indicated by the following?
Woman of childbearing age Missed LMP Sudden onset severe hypogastric pain radiating to sacral area Afebrile Localized peritonitis in suprapubic area Tenderness in rectouterine pouch
Ruptured ectopic pregnancy
What condition might be indicated by the following?
Elderly male with hx of atherosclerotic disease such as HTN or cardiac disease
Sudden onset severe back pain
Pale and shocked, hypotensive
Tender epigastrium
Palpable impulse from aneurysm in epigastrium
Leaking aortic aneurysm
