5. Esophageal Motility Flashcards
Esophagus is a hollow muscular tube that traverses cervical, thoracic and abdominal
compartments reaching _____in length and _____ in dimension
18-26 cm
2-3 cm expansion
Esophageal wall structure consists of four layers:
mucosa, submucosa, muscularis prorpia and adventitia:
upper quarter of the esophagus and upper esophageal sphincter (UES) are composed of
striated muscle
lower half of esophagus, along with intrinsic lower esophageal sphincter (LES) are
composed of
smooth muscle.
What structure reinforces the LES
Crural diaphragm
coordinated and propulsive
sequential contraction of the
esophageal muscle
peristalsis
• Primary peristalsis occurs in concert with appropriately timed relaxation of
the upperand lower esophageal sphincters.
How do you record peristalsis in the esophagus?
Primary peristalsis as recorded by an
intraluminal manometry catheter
triggered by swallow and associated with pharyngeal contraction and
UES relaxation
Esophageal Primary Peristalsis
Describe the features of secondary peristalsis
triggered by esophageal distention
Contraction starts PROXIMAL to distention
What controls the intrinsic and extrinsic peristalsis?
Intrinsic: Enteric neural plexus
Extrisinic: vagus
Swallowing (a) evokes a peristaltic wave of contraction that migrates
smoothly from the striated to smooth muscle esophagus. Simultaneous
electrical activation of all______ efferent neurons produces
________ in the striated muscle esophagus, and in the smooth muscle segment a ________ is induced.
vagal
simultaneous contractions
peristaltic wave
intrinsic neurons activated by vagal efferent nerve stimulation are capable of evoking a peristaltic contraction without the need for
centrally mediated sequencing.
Proximal esophageal striaghted muscle peristalsis we have a motor end plate and an action potetial… what occurs in the action potential
Ca 2+ Release mainly from sarcoplasmic reticulum via Ttubules
in the PROXIMAL part of the esophagus; Sequence of peristalsis is generated by the swallowing __________ of brainstem
“central pattern generator”
Distal Esophageal Smooth Muscle Peristalsis is generated by:
varicose nerve endings and gap jnxs with Ca+ influx from outside (unlike Ttubs in the proximal esophagus)
In distal esophageal smooth muscle, Peristalsis in smooth
muscle is physiologically regulated as
“a wave of inhibition followed by a wave of excitation”
Vagal efferent synapse on excitatory adn inhibitory myenteric mortor neurosns, what is the excitatory one and what happens?
Excitatory motor neurons: Predominantly Acetylcholine –>
Ca2+ release –> depolarization –> second messenger pathways
(substance P)
What the is vagal inhibitory neuron and it’s action
Inhibitory motor neurons:
Predominantly Nitric oxide –>cGMP dependent pathway –> inhibition of
Ca2+ entry–> hyperpolarization
• (Vasoactive intestinal peptide)
Described as: “Sticks”,“Caught”,“hangs up”
• Most specific esophageal symptom
• Almost always organic and different from globus sensation (always a lump in throat)
Dysphagia
Pain during swallow and bolus transit
Odynophagia
Dysphagia in what location?
sticks or hangs up after swallow
may or may not have chest pain
Esophageal dysphagia
Dysphagia when you have difficulty swallowing and cough or choke w/ nasal regurg
pharyngeal dysphagia
- Peptic stricture
- Esophageal ring
- Cancer
All are what kind of etiology of dysphagia
Mechanical
- Achalasia
- Esophageal spasm
- Dysmotility
are what etiology of dysphagia
neuromuscular
Uncommon______ causes of dysphagia:
- Scleroderma
- Chagas disease
- Collagen VascularDisorders
neuromuscular
Uncommon_____ cause of dysphagia
- Web
- Diverticulum
- Benign Tumors
- Foreign body
- Extrinsic (tumor)
Person over 50 comes in with progressive dysphagia, whats most likely dx?
cancer
Individual has dysphagia with Solid foods only and have chronic heartburn, cuase of dysphagia?
peptic stricture
Pt comes in with intermittent dysphagia of solid foods, dx?
esophageal ring
Pt has issues swallowing both solids and liquids. this is progressive and pts has heartburn adn regurg.
Scleroderma or Achalasia
Pt comes in with intermittent dysphagia of solids and liquids and has chest pain. Dx?
esophageal spasm
Diagnostic approach for Esophageal disorders includes?
Upper GI endoscopy: gets us structure info
Esophageal manometry: gives us functional info (squeeze pressure)
Radiography: Esophagram gives both
True and false
vocal cords and Arytenoids
Hypopharynx
is the technique for measurement of esophageal intra-luminal pressures
• The gold standard for diagnosis of esophagealmotor disorders
Esophageal manometry
- ____ relaxes for half a second to allow bolus passage
- ______ wave produces a lumen-occluding contraction with amplitude of 30-150 mmHg
- Peristaltic duration is _____ and migrates aborally at a speed of 3-5 cm/sec
- LES relaxes for 3-8 seconds to allow _______
UES
Primary peristaltic
3-7 sec
bolus emptying into the stomach
