GI Physiology Flashcards
(303 cards)
1
Q
What are the three top conditions of the upper GI tract
A
Peptic ulcer disease, gasto-esophogeal reflux, gastric cancer
2
Q
What are common presentations of gastroenterology pathology
A
Acute GI bleed, dysphagia, dyspepsia, abdominal pain, malabsorbtion
3
Q
What is dysphagia
A
Dysfunction in swallowing
4
Q
What is Dyspensia
A
dysfunction in stomach
5
Q
What are the three main functions of mastication
A
Lubricate food with salive
Physically grinds up food to facillitate swallowing
Being chemical digestion
6
Q
What are the two chemical digestive enzymes found in saliva
A
Salivary amylase and lingual lipase
7
Q
What is deglutination
A
swallowing
8
Q
What type of neural control is the muscle involved in swallowing innervated by
A
Muscles in back of oral cavity - Striated muscle under voluntary control, innervated by somatic motor neurons
Lower 2/3 of oesophagus - smooth muscle innervated by autonomic neurons
9
Q
What phases of swallowing are voluntary and involuntary
A
Oral phase - voluntary
Pharyngeal phase/oesophageal phase - involuntary
10
Q
Explain the oral phase of swallowing
A
Movement of food to the back of the mouth by the tounge, oropharyngeal receptors detect the food bolus and stimulate the next phase
11
Q
Explain the pharyngeal phase of swallowing
A
Soft palate lifts up to block the nasopharynx
Vocal chords close off opening of the larynx
Epiglottis folds down to cover vocal chords protecting the airway
Upper oesophageal sphincter relaxes, peristaltic waves push food through pharynx
12
Q
Explain the oesophageal phase of swallowing
A
Food bolus is moved towards the stomach by peristalsis contraction
13
Q
Where is the swallowing centre located in the brain
A
Medulla
14
Q
What cranial nerve is the vagal nerve innervated by
A
Carinal nerve 10 (X)
15
Q
What nerve and what cranial nerves are primarily involved in swallowing
A
Nucleus ambiguous
Cranial nerves IX and X
16
Q
Damage of what nerves can cause dysfunction of swallowing
A
V, IX,X
17
Q
What is Achalasia
A
Occurs when the LOS fails to relax during swallowing so food cannot pass through to the stomach
18
Q
What nerve is their dysfunction in during achalasia
A
Myenteric plexus
19
Q
What are 4 treatments options for people with achalasia
A
- medication (Ca2+ channel blockers, nitrates, beta blockers)
- Mechanical dilation
- Chemical paralysis (botox)
- Surgical myotomy
20
Q
What are common symptoms of GORD
A
heartburn, cough, sore throat
21
Q
What part of the anatomy is dysfunction in GORD
A
LOS is opening inappropriately
22
Q
What occurs to the epithelium in Barrett oesophogus
A
replacement of the oesophageal stratified squamous epithelium with columnar cells that are more similar to gastric mucosa
23
Q
What is the effect of GORD on oesophageal structure
A
Can result in narrowing of the oesophagus, making it difficult to swallow
24
Q
What is GORD most commonly treated with
A
Medications to reduce the secretion of HCl - histamine receptor blockers and proton pump inhibitors
25
What can be the consequence of pyloric obstruction
May result in persistent vomiting = malnutrition, loss of H+ ions = metabolic alkalosis
26
What can be the conseuqence of obstruction distal to the stomach
Anti-peristaltic reflux from the small intestine, intestinal juices flow back to stomach
27
What is the consequence of obstruction in the distal colon
constipation, which can eventually lead to vomiting, dehydration
28
What is esophagitis and which individuals are at high risk of getting it
Infection with candida (herpes simplex)
Common in immunosuppressed individuals
29
What sorts of cancers develop along different areas of the oesophagus
Squamous cancers in the middle and upper portions
Adenocarcinoma in lower third
30
What is gastritis, what can cause it
Inflammation of gastric mucosa
Caused by aspirin and alcohol
31
What can be a consequence of gastritis and why
Increased chance of ulcers due to increased permeability of the damaged mucosa susceptible to HCl damage
32
What would be the result of no HCl secretion
Pepsin wouldn't be activated
33
What is pernicious anaemia
Loss of intrinsic factor resulting in impacted absorption of vitamin B12
34
Where are gastric ulcers most commonly found
Near the pyloric sphincter
35
What are mechanically ventilated patients highly susceptible to developing
Highly susceptible to gastric stress ulcers.
They are treated with medication however this increases their chances of having colonisation by gram negative bacteria, causing pneumonia
36
What is the negative effect of gastric pH lowering medication such as proton pump inhibitors
They lower the ability for the mucosa to barrier against gram negative bacteria
37
What is Gastronoma
Rare disease where patients present with gastric ulcers due to high rates of gastric acid secretion
38
What is Omeprazole
potent inhibitor of parietal cells H+/K+ pump
39
What is Gastroparesis
Delayed gastric emptying
40
Where is the vomiting centre located in the brain
Postrema on the lateral wall of the 4th ventricle
41
What types of nerves are innervating the lower part of the upper GI tract
Vagal and sympathetic nerves
42
What types of motility pattern facillitates vomiting
Anti peristalsis
43
What initiates the actual vomiting act
Distention of the duodenum
44
What is the difference between regurgitation and vomiting
Regurgitation occurs without effort
45
In someone with regurgitation syndrome, how soon after a meal will they regurgitate
Within minutes of eating
46
What is the treatment for regurgitation syndrome
Cognitive behaviour therapy
47
What is functional dyspepsia
Discomfort in the upper abdomben area with no sign of ulcers
48
What are the two main gases in the stomach
oxygen and nitrogen
49
What are the 5 top presentations of people with lower GI tract pathology
Diarrhoea
Iron defincy anaemia
Rectal bleeding
Constipation
Tenesmus (cramping when bowel is empty)
50
What 2 motility patterns are in the SI
Segmentation (churning)
Propulsion (propagated peristaltic contraction)
51
Which intestine has fed/fasting motility
Large Intestine
52
What 2 motility patterns are in the LI
Non-propulsive segmentation
Mass movements
53
What is Hirschsprung disease
congenital polygenic disorder resulting in loss of neurons from submucosal and myenteric plexus
Cant relax their sphincters
54
What spinchters are effected in Hirschsprung disease
The internal anal sphincter does not relax after rectal distention but the external sphincter functions normally
55
What is Hartnup disease
Autosomal recessive disorder associated with the small internal and renal tubule dysfunction absorption of neutral amino acids
56
What is Cystinuria
Autosomal recessive disorder associated with dysfunction in absorbing cationic amino acids
57
What is lysinuric protein intolerance and what does it cause
Rare autosomal recessive disorder defect in basolateral membrane transports resulting in malnutrition
58
What is ceoliac disease
Autoimmune condition leading to mucosal inflammation in the upper small bowel
59
What epithelial changes are seen in ceoliac disease
Elongated crypts in duodenum and jejunum
60
What food group is mostly affected by pancreatic failure
Fats
61
What is hemochromatosis and what can it cause
This is excess iron which can cause cirrhosis in the liver if it reaches toxic levels
62
What causes secretory dihorreoa and what changes are their in the mucosa as a result of this
Viruses or bacteria cause secretory
The mucosa becomes irritated - increased insertion of Cl- channels into luminal membrane resulting in increased secretions
63
What is osmotic diarrhoea
Unabsorbed dietary nutrients in the intestinal lumen create an osmotic drive of fluid into the lumen
(i.e lactose deficiency)
64
What is psychogenic diarrhoae
Caused by excessive stimulation of the PNS which excites both motility and excess secretions
65
What changes would you see in a biopsy of someone with IBS
None - there are no visible changes in the histology of IBS
66
What is Crohns disease, where does it occur, what triggers is
Type of IBD - can occur anywhere in the GI tract. Inflammation
usually environmental triggers
67
What is ulcerative colitis
Colon becomes inflammated and ulcerated = bloody diarrhoea
68
What is the effect of ulcerative colitis on motility of the colon
Mass movements occur much of the day instead of the usual 3-10 minutes
69
What is diverticula and diverticulitis
Diverticular are abnormal pouches in colonic wall
Diverticulitis is inflammation of these pouches
70
What is usually associated with diverticulitis
Low fibre diet
71
What causes haemorrhoids/piles
Congestion of the venous plexuses around the anal canal
72
What is rectal prolapse
When the rectum loses its attachment and comes out through the anus
73
Rectocele prolapse
A type of rectal prolapse where the rectum sags and bulges into the vagina
74
What is intussusception
Where one part of the bowel slides into another (like collapsible telescope)
75
What part of defecation is not possible for someone with spinal cord injuries
The voluntary portion of defecation is blocked (external anal sphincter)
76
How are people with spinal cord injuries still able to deficate
Because the spinal cord reflex is still intact, a small edema is often enough to excite action of this cord reflex and stimulate adequate defecation
77
What are the 3 main gases in the lower GI tract
CO2, methane and hydrogen
78
What is the main cause of gases in the lower GI tract
bacterial fermentation of unabsorbed carbohydrates
79
What cranial nerve innervates the taste buds at the back of the throat
X - vagus nerve
80
During the pharyngeal phase of swallowing what causes the closure of naso-pharynx
Soft palete elevates and palatopharyngeal folds appose and close the nasopharynx
81
What are the layers of the gut wall from inside to out
Mucosa
Submucosa
Circular muscle
Myenteric plexus
82
What is the major difference between SI and LI mucosa
SI has microvilli
83
What is xerostomia
Dry mouth
84
What cells secrete the following things
HCl
Gastrin
Pepsinogen
HCl - parietal cells
Gastin - G cells
Pepsin - Cheif Cells
85
What is the main ionic component of fasting gastric juices
NaCl
86
What occurs to parietal cells when they are stimulated
Change morphology so they are able to increase the amount of apical surface area they have and insert more H+/K+ pumps onto this surface
87
What is the cephalic phase of gastric secretions and what nerve is this primarily mediated by
The smell, taste, thought and swallowing of food initiates the cephallic what
Primarily mediated by vagus nerve
88
What stimulates G cells
Partially digested proteins
89
What stimulates the secretion of gastrin in the duodenum
Acid
90
What is the most potent neural stimulator and inhibitor in pancreatic duct HCO3- secretion
Secretin - stimulator
Substance P - inhibitor
91
What food group does bile digest
Fats
92
What is pepsin activated by
Pepsinogen
93
Pepsin, trypsin and peptidases all digest what food group
Proteins
94
Arrival of fatty acids in the duodenum stimulate I cells to secrete what
CCK (which then stimulates bile from the liver)
95
What accounts for most of bilirubin production
Old red blood cells
96
What the 4 indications for esophogeal monometry
Dysphagia
GORD
Rumination Syndrome
Pre-fundoplication assesment of swallow
97
What are 4 contraindications for oesophageal manometry
Oesophageal varices
Large pharyngeal pouches
Large oesophageal diverticulum
Unable to tolerate procedure
98
What is the patient preparation for oesophogeal monometry
Fasting from 12 midnight before test
99
What is the contractile deceleration point (CDP) on oesophageal manometry
Point at which the speed of the peristaltic wave front slows
100
Where in the oesophogus does that contractile deceleration point occur
distal third of the oesophogus
101
What is contractile deceleration point associated with
ampullary emptying
102
What is the distal latancy in oesophageal manometry
Time from the onset of the swallow to the contractile deceleration point
103
What is the normal and premature contraction values of distal latency in oesophageal manometry
>4.5s = normal
<4.5s = premature contraction
104
What is the intergrated relaxation pressure in oesophageal manometry
The pressure during the 4 second period of maximal OGJ relaxation during a swallow
105
When does the integrated relaxation pressure begin
Onset of UOS relaxation
106
What does the distal contractile intergal measure in oesophageal manometry
Contractile vigor
107
What are the normal, weak, failed and hypercontractile values for distal contractile intergral in oesophageal manometry
>450 - 800 = normal
<450 = Weak peristalsis
<100 = Failed peristalsis
>800 = hypercontractile
108
What two values are needed in oesophageal manometry for there to be a failed swallow
DCI < 450
DL < 4.5s
109
What are the 3 essential tests done in oesophageal manometry
10 x single 5mls swallow
5 x single 5mls swallows
Salty water swallow - impedance test
110
What are the three provocative tests done in oesophageal manometry and what do they each assess
Multiple rapid swallows: 2mls water every 2s, 5 times. Assesses peristaltic reserve
Rapid drinking challenge: 200mls water consumed through straw. Assesses OGJ relaxation.
Solid swallows: bread and butter consumed in 8 minutes. Assesses the intergrity of swallows.
111
What classification is used to assess oesophageal manometry results
Chicago Classification 4.0 Hierarchical Classification Scheme
112
What measurements of IRP does there need to indicate pathology in oesophageal manometry
>15mmHg supine
>12mmHg upright
113
Is there are pathological IRP values with peristalsis, what condition does the patient have
GORD
114
If a patient has pathological IRP values with no peristalsis, what condition do they have
Achalsaia
115
Type 1 Achalasia
100% failed peristalsis without panesophageal pressurization
116
Type 2 Achalasia
100% failed peristalsis with > 20% panesophogeal pressurization
117
Type 3 Achalasia
>20% premature contraction +/- paneosophogeal pressurization
118
What 3 characteristics in oesophageal manometry results farther increases the validity of patholoigcal findings
Raised IRP in both upright and supine positions
Incomplete LOS relaxation
Lack of deglutitive inhibition in esophogeal body during rapid drink test
119
When can Chicago classifications not be applied to oesophageal manometry results
Post balloon dilation
Post Hellers myotomy
Post fundoplication
Large paraesophageal hiatal hernia
120
What type of Achalsia is least common and least responsive to treatment
Type III
121
What is deglutive inhibtion
When a swallow abruptly inhibits any ongoing contraction in the esophagus
122
During solid swallow provocative testing what OGJ relaxation pressure is considered normal
<25mmHg
123
What will be the abdominal pressure of someone with regurgitation syndrome
>30mmHg
124
What is the DeMeester score used for
Used to determine if someone has GORD using results from the 24 hours pH test.
125
What values are used in the DeMester score test
Compares the amount of time acid remains in the oesophagus and the amount of reflux episodes
126
What is a normal DeMeester scoire
<14.2
127
What is symptom association probability (SAP) and what value does this need to be for a positive GORD indicator
Measures the strength of the relationship between reflux and symtoms
>95% = postiive for GORD
128
What does acid exposure time (AET) syptom correlation measure and what value is required for a positive GORD result
Correlation between acidic changes measured in the test and symptoms experienced
>50% = postiive
129
What is effect of liquid on impedance during 24hr pH and how does this look on a graph
Retrograde decrease in impedance (look like a bowel on a graph)
130
What is the effect of air on the impedance in 24hr pH testing and what does this look like on a graph
Anterograde increase in impedance (looks like a flat mountain)
131
What results must be seen on 24hr pH trace for an event to be considered an acidic reflux event
Must have a decrease in impedance >50% of baseline and pH <4
132
What results must be seen on 24hr pH trace for an event to be considered an non-acidic reflux event
decreased impedance of >50% and decrease in pH > 4
133
What does esophogeal impedance testing measure
The movement of substance through the oesophogus
134
24hour pH monitoring can detect both acidic and non-acid reflux, true or false?
False - 24 hour pH testing can only detect acidic reflux
135
What 4 characteristics is esophogeal impedance testing and 24hr pH testing combined able to measure
Content of the relfux
Direction of bolus
Height of reflux in oesophogus
pH characteristics
136
Where is the catheter places in 24hours pH tests
5cm above the upper boarder of the OGJ
137
What is the catheter calibrated to prior to 24hr pH testing
pH 4 and pH 7
138
If a patient has normal acid exposure negative SAP what diagnosis do they have
functional heartburn
139
If a patient off PPIs has normal acid exposire, positive SAP what diagnosis do they have
reflux hypersensitivty
140
If a patient off PPIs has abnormal acid exposure and inconclusive SAP what diagnosis do they have
NERD
141
If a patient, on PPIs, has abnormal acid exposure what diagnosis do they have
GERD
142
What is the Lyon Consensus
International consensus for diagnosis for GERD
143
What is Mean Nocturnal Baseline Impedance (MNBI)
Impedance-pH metric assessing mucosal integrity of the oesopgogus due to chronic acid reflux
144
What value of MNBI is abnormal and what pathology does this suggest
<2292 ohms
Inflamed esophogeal muscosa
145
What is post reflux swallow induced peristaltic wave (PSPW)
Anterograde progression of impedance decline within 30s of a reflux episode on a pH-impedance study
146
What is supragastric belching
Phenomenom where air is rapidly drawn into the oesophogus and expelled without reaching the stomach
147
The London Classification outlines classification for what disorders
Anorectal Function
148
What does high resolution anorectal manometry measure
Anorectal muscle function
149
What are 4 indications for anorectal manometry
Referred after organic pathology excluded
Constipation/evacuation disorders
Preoperative assessment
Assessment after obstetric injury
150
What patient preparation is required for anaorectal manometry
Continues to take all meds, no fasting required
151
What is the longitudinal recording length of anorectal manometry
6cm
152
Where should the base of the rectal balloon be based in anorectal manometry
3-5cm above the upper border of the anal canal
153
What is the maximum inflation of the balloon during anorectal testing
400mls
154
How do you measure the rectal anal inhibitory reflex in balloon testing
ramp the baloon 1-5mls/second
155
How do you test the rectal sensation during anorectal balloon testing
physically add 10mls/second
156
What is the balloon expulsion test in anorectal testing
Balloon is filled with 50mls water and measuring the ability for the patients to expel the balloon in <1min
157
What measurement in anorectal manometry can you use to measure the internal anal sphincter function and why
Resting pressure can be a good indicator of internal anal sphincter function.
This is because the anal sphincter accounts for 52-85% of resting pressure
158
What should the rise in pressure be when patients are asked to voluntarily activate the external anal sphincter
Should see the pressure rise at least double and the patients should be able to squeeze for at least 20seconds
159
What is type 1 defecatory dyssynergia
Sufficient rise in rectal pressure (>40mmHg) + paradoxical anal sphincter contraction
160
What is type 2 defecatory dyssynergia
Insufficent rise in rectal pressure (<40mmHg) + paradoxial anal sphincter contraction
161
What is type 3 defecatory dyssynergia
Insufficient rise in rectal pressure + insufficient anal sphincter relaxation
162
What are the London Classifications for type 1, 2, 3, 4 anorectal disorders
I = disorders of the rectoanal inhibitory reflex
II = disorders of anal tone and contractility
III = disorders of rectoanal coordination
IV = disorders of rectal sensation
163
Contraction of the abdominal rectus generates what and should result in what
Should generate rectal drive
Causing relaxation of anal sphincter muscles and stool evacuation
164
What 3 conditions are investigated through hydrogen methane breath testing
Small Intestinal Bacterial Overgrowth (SIBO)
Fructose Malabsorbtion
Lactose malaborbtion
165
What sort of respiration does bacteria in the colon primarily use
Anaerobic
166
What dietary group is usually responsible for the production of hydrogen and methane gases
Carbohydrates and short chain fatty acids
167
What does the bacteria in the small intestine absorb that leads it to release excess gas, and what gases does it release
SI bacteria absorb glucose creating hydrogen and methane
168
In a hydrogen breath test, what measurement is truly positive for SIBO
>20PPM spike in hydrogen is consistent with a truly positive SIBO test
169
What are some indications for hydrogen methane breath testing
Fluctuance, bloating, diarrhea, abdominal pain, constipation
170
What is the result of methane on the gut motility
Methane production slows intestinal transit
171
What is the course of treatment for a positive SIBO test
Antibiotics for SI infection
172
What will be the next course of action if a SIBO test comes back negative
Lactose and fructose malabsorption tests will be carried out
173
What is the suggested treatment for those with a positive lactose and fructose malabsorption test, respectfully
Lactose - lactose free diet
Fructose - low FODMAP diet
174
What are the two primary causes of SIBO
Anatomical abnormalities (recent surguries)
Small intestinal motility disorders
175
What type conditions are commonly associated with fructose malabsorbtion
IBS and ceoliac disease
176
What is the difference between lactose intolerance and lactose malabsorbtion
Intolerance is the symptoms that occur due to lactose malabsorbtion.
Malabsorbtion is the intestinal inability to digest or absorb lactose sugar
177
What are the 5 patient preparations for hydrogen methane breath testing
Avoid antibiotics 4 weeks prior
No colonoscopy/full bowel cleaning prep
Withdrawn motility enhancing drugs or laxatives 1 week prior
Refrain eating complex carbs 24 hours before test
Fasting 12 hours prior
178
What is the solution given to non diabetic patients having hydrogen methane breath testing for SIBO
70g glucose
300mls water
179
What is the solution given to diabetic patients having hydrogen methane breath testing for SIBO
10g lactulose in 300mls water
180
What is the solution given to non diabetic patients having hydrogen methane breath testing testing for fructose malabdorbtion
25g fructose in 300mls water
181
What is the solution given to diabetic patients having hydrogen methane breath testing for lactose malabsorbtion
25g lactose in 300mls water
182
How often is a breath sample taken during hydrogen methane breath testing for glucose/lactulose testing
Every 15mins for 90mins
183
How often is a breath sample taken during hydrogen methane breath testing for fructose
every 30mins for 180 mins
184
How often is a breath sample taken during hydrogen methane breath testing for lactose testing
every 60minutes for 180 minutes
185
What would a double peak of hydrogen in a hydrogen methane breath test results indicate
Hydrogen is being produced in multiple parts of the SI
186
What result for methane in the hydrogen methane breath testing would be indicative of a positive test for SIBO
>10ppm baseline
187
Why is high baseline methane not a indicator of SIBO
Usually all patients having a hydrogen methane breath test will have increased baseline methane, doesnt mean they have SIBO
188
What would a flat line response to a hydrogen methane breath test indicate
Patient predominately produces hydrogen sulphide
189
What are the 4 types of capsule endoscopies
Small bowel, UGI, Colon, Chrons
190
What are some indications for capsule endoscopy
GI bleeding, iron deficiency, IBD
191
What are 3 contraindications for capsule endoscopy
Swallowing disorders, small bowel obstruction, pregnancy
192
How long is the recording period for the UGI capsule
1.5 hours
193
What is the use of the patency capsule in capsule endoscopy
This is a capsule that disintegrated in the GI tract, and is given to patients before a capsule endoscopy if potential obstruction is suspected
194
What is the recording period for Colon/Chrons capsule endoscopy
15 hours
195
In what time period does the patency capsule need to be passed for it to indicate capsule endoscopy can go ahead
Must be passed or disintergrated in <30 hours
196
At what point is a capsule considered a 'retained capsule' during capsule endoscopy
When it has been retained proximal to the intestinal narrowing for at least 2 weeks
197
What is the major advice given to patients regarding further medical treatment after a capsule endoscopy
They should not be receiving any MRI scans for 14 days following the capsule, or if they are unsure if they have passed it or not
198
Was wavelength decreases what happens to the amplitude of the wave and the frequency
Amplitude stays the same
Frequency increases
199
What is radiological density of tissue determined by
Density of the tissue and the atomic number
Higher atomic number, more absorbtion
200
What type of barium is used in barium x ray and why
Barium sulphate - it is not toxic because it is insoluble so never absorbed
201
What preparation is required for patients in advance to barium xray
Fasting
202
What does barium xray allow us to image
Barium spreads along the GI tract so you can see the length of it.
Videoflouroscopy is also used to image movement such as swallowing, bolus movement down the oesophagus or gastric emptying
203
What is barium enema and what is it used for
This is when barium sulphate is injected into the rectum and the patient is asked to expel the paste during xray.
Used to analyse dysfunction in stool evacuation
204
What is radiopaque marker test and what does it allow us to image
Patient is given capsules to swallow with metal bits in them. The progress off these moving down the GI tract is then analysed on xray
Looks at the rate of which components transit through the GI tract
205
What is the relative energy and wavelength of gamma rays in comparrison to xrays
Gamma rays have higher energy and smaller wavelegnths
206
What gamma ray matierial is commonly used in medical diagnostics
Technetium-99m
207
What is radionuclide scintigraphy
Used to non-invasively monitor progress of a radioisotope marker through the intestinal tracks using scintillation or gamma camera
208
What is the gold standard test for measuring colonoic transit
Radionuclide scintigraphy
209
In radionuclide scintigraphy, what test is indium used for and why
Used for assessment of small intestinal and colonic motility because it has a longer half-life
210
When do the indium capsules dissolve in radionuclide scintigraphy and what does this ensure
These dissolve in the distal small intestine to ensure the bolus is released close to the colon
211
How is intraluminal movement expressed in radionuclide scinigraphy
Calculating the geometric centre of the isotope mass in discreetly defined regions of the colon
212
What nervous system is responsible for regulation of gastric smooth muscle
Parasympathetic
213
What are varicosities
Connections between smooth muscle cells
214
What is the behaviour of multiunit smooth muscle cells when they receive synaptic input
When in a multi unit, they can either all contract, or they can also contract independently.
215
What sort of smooth muscle makes up the smooth muscle of the stoamch
Visceral smooth muscle
216
Where is the pacemaker region of the stomach
Antrum
217
Where do slow waves in gastric motility arrise from
Antrum
218
How many slow waves are there in the stomach per minute
~3
219
What cells are the pacemaker cells in the stoamch
Interstital cells of Cajal (ICCs)
220
What are slow waves initiated by
Spike potentials
221
What ion is responsible for driving gastric contractions
Ca2+
222
What is the duration of the spike potentials in gastic motility
100ms
223
What is the results of lumen size when there are circular and longitudinal contractions in the stomach, respectfully
Circular contractions decrease lumen size
Longitudinal contractions decrease lumen legnth
224
What motility underlies grinding activity of the stomach
Propulsive and retrograde contractions
225
Accommodation of the stomach contributes to what
Intragastric pressure which is important for the sensory feedback to the stomach
226
What part of the stomach is primarily involved in storing dietary food and liquids
Proximal region
227
What part of the stomach is primarily involved in mixing the food with the secretions in the stomach
Distal region
228
What types of waves are seen on EGG
Sine waves
229
What filter is used in EGG
Low pass filter - this helps exclude artefact including the heart beat
230
What is the filter band frequencies in EGG machine
0.5Hz - 0.16Hz
231
What sampling frequency would be suffient for EGG machine
1Hz
232
Do patients have to fast in preparation for EGG
Yes
233
Where are the leads for an EGG being placed
Over the antrum
234
What three conditions is EGG used to investigate
Functional dyspepsia
Nausea or vomiting
Gastroparesis
235
What are the 6 possible clinical interpretations for EGG
1. Normal
2. Tachygastria
3. Bradygastria
4. Nonspecific rhythm pattern
5. Lack of post prandial power increases
6. Uninterpretable secondary to technical problem or motion artefact
236
During tachygastria, what motility pattern is common and what does this result in for the state of the stomach
Retrograde depolarisation may propagate with tachycgastria due to the increased amplitude inducing contractions.
This can cause the stomach to become atonic (limp)
237
What is a normal EGG result trace
frequency of waveforms remains constant (~3cpm) but amplitude increases with food ingestion
238
What are 4 symptoms of oesophageal dysfunction
Ineffective transport of food from mouth to stomach
Dysphagia
Odynophagia (pain on swallowing)
Patients may descibre "food getting stuck"
239
What is the first line of investigation when people complain of difficult swallowing
Gastroscopy to exclude any organic pathology
240
What are the two main conditions associated with disorders of OGJ outflow
Achalasia and OGF outflow obstruction
241
What are the 4 conditions associated with disorders of peristalsis
Hypercontraction, absent peristalsis, DOS, IOM
242
What is the primary cause of achalasia believed to be
Selective loss of inhibitory neurons in the myenteric plexus of the distal eosophogus
243
What do excitory and inhibitory neurons release in the oesophagus, respectfully
Excitory - Ach
Inhibitory - Vaso active intestinal peptide and NO
244
What types of achalasia are receptive to Hellers myotomy treatment
Type 1 and Type 2
245
Is peristalsis concerved in OGJ outflow obsturction
Yes
246
What is the relative level of peristaltic waves and DI value in hyp0contractility of the OGJ
DI will be low (<450) and peristaltic waves will be low
247
What is hypocontractility of the OGJ usually due to
Connective tissue disease
247
What is hypocontractility of the OGJ usually the most common cause of
GORD
248
Those with IOM, what HRiM test can sometimes trigger their eosophogus to work
Solid food test
249
What is a feacal immunochemical test
Test to see if there is blood in the stool
249
What is endoscopic retrograde cheolangiopancreatography
is an endoscopic and fluoroscopic procedure in which an endoscope is advanced into the second part of the duodenum, this allowing other tools to be passed into the biliary and pancreatic ducts
249
What is the main cause assocaited with DOS
Opioid use
250
What compound found in stool can distinguish between IBD and non-inflammatory bowel conditions such as IBS
Fecal Calprotein
250
What is a ova, cysts and parasites test
To see if there are any parasites in the GI tract
250
What are 3 indications for esophogeal gastro duodenoscropy (Upper endoscopy)
Persistant abdominal pain
GI bleed
Chronic symptoms of GORD
250
What are 3 indications of colonoscopy
Lower GI bleeding
Surveillance of polyps
Chronic dihorrea
251
What does the Barium Swallow test allow us to assess
Structural changes in the upper GI tract
251
What is the aim of timed barium column study
Assess the oesophageal emptying in patients with suspected achalasia
251
What is video-flouroscopy useful for assess
The oro-pharyngeal phase of swallow
251
What does endo-anal ultrasound allow us to assess
Images the anal sphincters and its surrounding structures as well as the pelvic floor
252
Antacids
- What do they treat
- How do they do it
- Side effects (2)
- When do they need to be withdrawn for 24hr pH testing
Treat mild dyspepsia/heartburn
Neutralise gastric acid and trigger mucosal lining in the stomach to releive burning sensation
Constipation and rebound hyperacidity when discontinued
Withdraw 48 hours before 24hr test
253
Alginates
- What do they treat
- How do they do it
- When do they need to be withdrawn for 24hr pH testing
GORD
Creates a mechnical barrier that displaces the acid in the stomach into a pocket
Withdraw 48 hours before 24hr pH testing
254
H2 receptor antagonist
- What do they treat
- How do they do it
- Side effects (3)
- When do they need to be withdrawn for 24hr pH testing
GORD, peptic ulcers
Inhibit secretion of gastric acid through competitive inhibition of Histamine H2 receptor on parietal cells
Diarrhoa, headache, dizziness
Withdraw 48 hours before 24hr test
255
PPI's
- What do they treat
- How do they do it
- Side effects (4)
- When do they need to be withdrawn for 24hr pH testing
GORD
Bind to H+/K+ATPase on parietal cells to inhibit secretion of HCl
Headache, abdominal pain, decreased bone density, pneumonia
Withdraw 10 days before 24hr pH study and 2 weeks before H.Pylori test
256
Mucosal protective agents
- What do they treat
- How do they do it
- Side effects (1)
- When do they need to be withdrawn for 24hr pH testing
Ulcers
Basic aluminum salt that locally covers the ulcer site and protects it from future attack by acid
Constipation
Withdraw 10 days before 24hr test
257
What are prokinetic agents used for
To enhance the motility by increasing frequency and/or the amplitude of contractions in the stomach
258
What type of drug is metoclopramide
Prokinetic agent - dopamine receptor antagonist
259
What type of drug is Motilium and what condition is it used to treat
Prokinetic agent - dopamine D2 recpetor antagonist.
Used to treat GORD
260
What type of drug is prucalopride
5-HT4 agonist that facilitates GI smooth muscle contractility while suppressing the resistance to propulsion due to circular smooth muscle contraction
261
What drug can be good for refractory constipation
Prualopride
262
What precautions must we as CMPs take patients on Ca2+ channel blockers and Opioids when preparing them for GI testing
We cannot take these patients of these drugs without consulting their physician first
263
What can be a negative implication of Ca2+ blockers in regards to GI pathology
Ca2+ channel blockers are thought to increase the risk of GORD by significantly reducing the tone of the LOS and increasing esophageal exposure to gastric acid
264
What is the effect of Botox on the esophogeal spincheter
Reduces tone of sphincter muscles
265
When should laxatives be withdrawn prior to hydrogen and methane breath testing
1 week
266
What are bulk forming laxitives and an example of it
Organic polymers that absorb water and thus increase stool water content
E.g psyllium husk
267
What is the mechanism of action of stool softers and and example of one
Surface active agents that facilitate water interacting with the stool in order to soften it
E.g arachis oil
268
What is the mechanism of action of osmotic laxatives and an example of one
These are poorly absorbed ions or molecules that create an osmotic gradient within the intestinal lumen, drawing water into the lumen and making the stool soft.
E.g lactulose
269
What is the mechanism of action for stimulant laxitives and an example
Increase peristalsis in the large bowel and fluid secretion in the distal small bowel
E.g bisacody
270
When would the use of antidiarrheal medication be contraindicated
If it is accompanied with high fever, blood in stool, or when inhibition of peristalsis is dangerous for the patient
271
What are some dietary modifications that can be used to treat dysphagia
Softer foods, avoid foods of hot/cold temperature, change consistency of food to maximise swallowing safely
272
What are some behavioural modifications for people with dysphagia
Remove excess distractions when you can, refrain from speaking with eating, special cups/straws can be used, plates fitted with dividers
273
What are some postural adjustments to treat dysphagia
Upright posture during eating and 1 hour post meal
274
Effortful swallowing exercise
Gather the saliva in your mouth in the middle of your tongue. Keep your lips pressed together. Swallow all the saliva at once like you’re swallowing a grape or pill
275
Dynamic shaker swallowing exercise
Lie on your back on a flat surface. Make sure your shoulders are against the surface and do not use a pillow. Lift your chin but keep shoulders down as if you’re trying to look at your feet. Lower your head to the surface, repeat.
276
Jaw thrust swallowing exercise
push your lower jaw as far forward as possible, placing your lower teeth in front of your upper teeth. Hold. Repeat.
277
Masko manoeuvure swallowing techniqie
stick your tongue out of your mouth. Bite down on your tongue to keep it in place. Swallow while holding your tongue between your teeth. Release your tongue. Repat.
278
Mendelsohn Manoeuvure swallowing technique
locate the adam's apple with three fingers. Swallow once, noticing the swallowing movement. Swallow again, and squeeze your throat muscles to hold your Adam's apple at its highest point.
279
Supraglottic manoevrure swallowing exercise
collect saliva in your mouth. Take a deep breath and hodl it. Swallow while holding your breath. Immediately after swallowing, cough.
280
Hyoid lift manoeuvre
use straw to suck up small pieces of paper and transfer to a cup
281
Pitch glides swallowing manouvure
Sing ‘ee’ starting a low tone and then slowly raise your tone to your highest pitch. Hold this pitch for 10-2-0 seconds.
282
How are some ways you can activate sensory-motor feedback in dysphagia
Thermal simulation (cold)
Taste stimuli (sour)
Surface electrical stimulation of neck muscles
283
What are some feeding stratagies for people with dysphagia
Tube feeding if insuffient nutrition
284
2 surgical strategies for people with dysphagia
Botox injections, esophageal stents
285
Lifestyle modifications for people with GORD
Keep head elevated
Try lose weight
Stop smoking
Avoid alcohol, coffee, mint
No eating 2 hours before bed
286
Dietary stratagies for people with gastroparesis
Avoid fatty foods
Eat smaller meals, more frequently
Eat more liquid based foods
287
Surgical treatments for gastroparesis
Botox injection
Endoscopic pyloric dilation
Gastric pacing
288
What type of exercise is best for helping gastric motility
Light exercise - walking
289
Dietary strategies for function dyspepsia
Herbal therapies (peppermint, caraway oil)
Pre/probiotics
290
Psychological and behavioural therapies for function dyspepsia
Cognitive behavioural therapy
Hypnotherapy
Acupuncture
291
Dietary and lifestyle changes for nausea/vomiting
Maintain hydration, bland foods, avoid fatty/spicy/sweet foods.
292
Non-pharamalogical treatments for functional gastrointestinal diroders
e.g IBS - low FODMAP diet, herbal supplements, reduced environemtnal stress
293
Non-pharmalogical treatments for inflammatory bowel disease
Rich vegetable diet, low FODMAP, physical activity, CBT
294
