Case 1 - swallowing and dysphagia Flashcards
what are the three phases of normal swallowing
oral phase
pharyngeal phase
oesophageal phase
what is included in the oral phase
striated muscle
neural control is by the cortex and the medulla
full voluntary control
what is included in the pharyngeal phase
striated muscle
medulla neural control
some voluntary control
what is included in the oesophageal phase
striated/smooth muscle
medulla/ENS neural control
no voluntary control
what occurs in the oral phase
components for the preparation of bolus and initiation of swallowing
what is chewing
prepares solid food for transfer through the pharynx
the effectors are the teeth, jaws, and masseter muscles
what is salivation
lubricates bolus and begins digestion
the effectors are mucus, amylase, lipase, water and HCO3-
what is the movement of bolus
delivers prepared bolus to oropharynx
the effectors are the tongue
bolus transfer from the mouth to the oesophagus
what are the boundaries of the sphincters defined by and what do they prevent
defined by sphincters and these sphincters prevent influx of air and reflux of gastric contents into the oesophagus
what is the atmospheric pressure
0mmHg
what is the upper oesophageal sphincter pressure
100mmHg
what is the intraoesophageal pressure
-5mmHg
what is the lower oesophageal sphincter pressure
20mm
what is the intragastric pressure
5mmHg
what prevents reflux
the lower oesophageal sphincter having a higher pressure than the intragastric one
neuroanatomy of swallowing diagram
what is the nucleus solitarious
primary an afferent relay centre in the medulla
what is the nucleus of trigeminal
output from this system and have the dorsal motor nucleus and nucleus ambigous
what is the the nucleus ambiguous to do with
swallowing
what is transcranial magnetic stimulation used for
to oversee this action and tell us about the integrity of this system
what is oropharyngeal dysphagia
abnormal bolus transfer to the oesophagus
difficulty initiating a swallow
only one manifestation of the primary disease e.g stroke
what is oesophageal dysphagia
abnormal bolus transport through the oesophagus
Food stops after initiation of swallow
Oesophagus is the location of the primary disease e.g achalasia
what are the methods used to look at swallowing
VFS
fiberoptic endoscopic examination of swallowing
dysphagia after a stroke
common - 50% of all stroke victims
Usually oropharyngeal
30% increased risk of mortality
Aspiration most important complication
Natural swallowing recovery in majority
Decisions about alternative feeding difficult
Optimal timing
Method of delivery
treatment options limited
SALT
what side of the brain takes on the swallowing mechanism after a stroke
the non-dominant side of the brai
what allows pressure to be used to measure the swallow in the oesophagus and the sphincters
manometry
what is manometry
More precise measurement of upper GI motility
Catheters with multiple sensors <2cm apart (24+ arrays)
Spatiotemporal or topographic plot of pressure data (Clouse Plots)
Evolutionary technology
what is Clouse plot
display method can Improve accuracy and speed of recognition of motility disorders even in manometry-naive individuals
It is a coloured plot
We get location, temporal and pressure information
what is achalasia
failure of a ring of muscle fibres such as a sphincter of the oesophagus, to relax
what gene is achalasia associated with
HLA-DQw1
what suggests that alchasia may be autoimmune
circulating antibodies to enteric neurone s
what is the prevalence of achalasia
annual incidence of approx 1 case per 100,000
Men = women
Onset before adolescence unusual
Usually diagnosed between the ages of 25 and 60 years
what is used to diagnose achalasia
clinical history
Endoscopy
Radiology
Manometry
In one series of 87 consecutive patients with newly diagnosed achalasia, the mean duration of symptoms was 4.7 years
what would endoscopy reveal
may reveal a dilated oesophagus containing residual material
May appear normal
Oesophageal stasis predisposes to candida infection that may be apparent
what would be the radiology findings
barium swallow diagnostic accuracy around 95%
Dilated oesophagus with beak like narrowing
Dilation may be so profound that the oesophagus assumes a sigmoid shape
Fluoroscopy reveals the absence of peristalsis
Purposeless, spastic contractions can be observed - some radiologist call this vigorous achalasia
what would manometry show
manometric examination is usually required for confirmation
Three primary findings:
Elevated resting LES pressure - above 45mmHg
Incomplete LES relaxation - this manometric finding distinguishes achalasia from other disorders associated with aperistalsis
aperistalsis - in the smooth muscle portion of the body of the oesophagus. For most patients, low amplitude; in some cases, however, the simultaneous oesophageal contractions have higher amplitudes (>60mmHg) such patients are said to have vigorous achalasia.
what is botulinum toxin
endoscopic injection of BT (type A) into the lower oesophageal sphincter.
mechanism of action of botulinum toxin
inhibits the calcium dependent release of acetylcholine from nerve terminals, thereby countering the effect of the selective loss of inhibitory neurotransmitters
is botulinum toxin effective
it is initially effective in relieving symptoms, in about 85% of patients.
symptoms recur in more than 50% of patients within 6 months, possibly because of regeneration of the affected receptors
what is pneumatic dilation
most effective non-surgical treatment for achalasia
involves placing a balloon across the lower oesophageal sphincter, which is then inflated to a pressure adequate to tear the muscle fibres of the sphincter
what is Hellers Myotomy
involves carrying out an anterior myotomy across the lower oesophageal sphincter
however, whether myotomy should be combined with an antireflux procedure is a cause for debate
how are myotomies usually carried out
laparoscopically through the abdomen with a 1-2c distal myotomy onto the stomach
what is the major complication of Hellers myotomy
uncontrolled gasto-oesophageal reflux in 10% of patients
