GI Flashcards
1
Q
Disorders of the esophagus affect: (2)
A
motility or sphincter tone
2
Q
Achalasia
A
impaired relaxation of lower esophageal sphincter
too much tone!
3
Q
GERD
A
consequence of failure of normal antireflux barriers to work properly
4
Q
Barrets esophagus
A
Result of chronic GERD, risk for adenocarcinoma of espohagus
5
Q
What disease can cause achalasia?
A
- DM
-Stroke
-ALS
-connective tissue diseases (amyloidosis and scleroderma)
6
Q
Achalasia pathyphys
A
destruction of nerves to LES followed by degeneration of function of esophageal body
7
Q
Results of achalasia
A
-HTN of LES
-Failure LES to relax = reduced peristalsis
-dyphagia, regurg, weight loss
-aspiration risk
8
Q
Esophagectomy complication
A
10-15% morbidity/mortality
ARDS 10-20%
9
Q
Esophagectomy complications
A
-anastomotic leaks
-dumping syndrome
-esophageal strictures
-high risk aspiration
10
Q
If someone has had a recent esophagectomy, you should not
A
give cricoid pressure because you could rupture the esophagus
*even though patients are at high risk of aspiration
11
Q
UES location
A
between pharynx and cervical esophagus
12
Q
LES location
A
esophagus meets stomach
13
Q
During bag/mask, keep pressure under
A
20 mm H20
14
Q
Keep PIP under _____
A
30 mm H2O
15
Q
Primary GERD defect
A
resting tone of lower esophageal sphincter (LES)
13 in GERD vs 29 w/o GERD
16
Q
Barrier pressure at reflux
A
HIGHER barrier pressure = lower liklihood of reflux
17
Q
Barrer pressure =
A
Barrier pressure = LES pressure - Intragastric pressure
18
Q
____ LES pressure ____ barrier pressure
A
higher LES Pressure increases barrier pressure (good thing, less reflux)
19
Q
______ Intragastric pressure ____ barrier pressure
A
high intragastic pressure decreases barrier pressure (bad thing, more reflux)
20
Q
Things that decreases barrier pressure by decreasing LES tone
A
(bad thing, want higher tone)
-Anticholinergics
-Cricoid Pressure
-Pregnancy
21
Q
Things that decrease barrier pressure by increasing intragastric pressure
A
(bad thing, want decreased intragastric pressure)
-Pregnancy
22
Q
Things that increase barrier pressure
A
-Metoclopramide (increases LES tone)
(good thing, want increased tone)
23
Q
Things that don’t affect barrier pressure
Why?
A
-Succinylcholine
Succ increases LES tone and intragastric pressure = 0 net change
24
Q
What constitutes an aspiration risk (think stomach contents/pH?
A
- 0.4 mL/kg of gastic volume
- pH < 2.5
25
Drugs that increase LES tone (know apex):
see cardflow
- Metocloperamide
-Succ
-Domperidone
-Prochloroperezine
-Metoprolol
-antacids
-alpha-adrenergic stimulants
26
Drugs that decrease LES tone will ______ of gastric reflux
drugs that decrease LES tone will increase risk of gastic acid reflux
27
Drugs that decrease LES tone:
see cardflow
- atropine and glyco
-dopamine
-nitroprusside
-tricyclic antidepressants
-beta adrenergic stimulatnts
-opioids
-propofol
28
Sodium citrate MOA and who to give it to
-increases gastric pH
give with metoclopramide to diabetic, obese, pregnant
29
Cricoid pressure compresses:
Lumen of pharynx between cricoid cartilage and cervical vertebrae
30
____ is superior to all other devices in reducing aspiration risk
ETT
31
Hiatal hernia
herniation where part of the stomach is in thoracic cavity
32
Major autonomic functiion of stomach supplied by:
2 branches of vagus nerve
33
Pyloric sphincter
True anatomic sphincter between stomach and duodenum
34
gastric acid is secreted by ______ and is regulated by _____
secreted by parietal cells and is regulated by:
1. Ach
2. Gastrin
3. histamine
35
Somatostatin role
inhibits gastric acid secretion
36
somatostatin release is stimulated by:
presence of intraluminal acid at pH of 3 or less
37
Somatostatin MOA
1. Inhibits gastrin relase
2. modifies histamine release
38
Major hormonal regulator of gastric phase of acid secretion after a meal
gastrin
39
gastrin released by
G cells in response to gastric distention, which stimulates parietal cell acid secretion
40
Pepsinogen and gastrin release are _______ mediated
vagally mediated
41
Most of the blood supply to the stomach is from
celiac artery
42
Ulcers are caused by
loss of mucosa d/t inflammation
43
Ulcers are a result of
overabundance of hydrochloric acid and pepsin
^erode protective mucosal layer
44
Many gastric ulcers are a result of _____ infection
H. Pylori
45
2nd most common population with ulcers is
patient on NSAIDS
46
Most common complications of PUD
1. Hemorrhage
2. perforation
3. obstruction
(in order of prevalence)
47
Acute stress gastritis is associated with:
shock, stress, resp. failure, hemorrhage, mass transfusion, multiorgan injury
that is why the ICU pts all get pepcid :)
48
Drugs for ulcers
apex?
Oral antacids
H2 receptors antagonists
Proton pump inhibitors
Sucralfate
Antibiotics
49
H2 antagonists MOA
block hydrochloric acid secretion to promote healing
50
H2 antagonists
Cimetidine
Ranitidine
Famotidine
Nizatidine
51
PPI MOA and examples
Block hydrochloric acid
-azoles
52
Sucralfate MOA
binds to ulcers and increases gastric mucous layer (promotes healing process)
53
Misoprostol is a _____. MOA?
Synthetic prostaglandin
preventative therapy for ulcers in pts taking NSAIDS
54
Antibiotic MOA in ulcers
tx gram neg bacteria (H. Pylori)
55
Milk - alkali syndrome: what is it and what does it cause
can occur with daily ingestion of lg amounts of calcium containing antacids and milk
can cause:
-hypercalcemia
-alkalosis
-elevated BUN
56
antacids can produce
Acid rebound
gastric acid secretion increases after acid it neutralized
57
awake N pressure
10-20 N (1-2 kg)
58
Asleep N prssure
30 N or 3 Kg
59
Zollinger Ellison Syndrome
hypersecretion of gastrin (non-beta islet cell tumor of pancreas)
gastrin stimulates acid secretion = PUD, erosive esophagitis, diarrhea
60
Postgastrectomy syndromes (2)
1. Dumping syndrome
2. ALkaline Reflux gastritis
occur as result of gastric surgery for peptic ulcer dz or gastric neoplasm
61
Dumping syndrome tx
octreotide before a meal
62
In severe vases of UC, ____ will be low
albumin
63
What is associated with acute onset of UC?
toxic megacolon
64
In all inflammatory bowel diseases ( Chrohns, UC), ____ is commonly low
Potassium
65
Intraoperative fluid replacement for inflammatory bowel disease
5-6 mg/kg/hr is a good starting point
66
inflammatory bowel disease: what is commonly low?
Albumin and K
hypoalbuminemia and hypokalemia
67
Carcinoid tumors consist of slow growing malignancies composed of
enterochromaffin cells
secrete bioactive humoral agents
they are mostly commonly found in GI tract, most commonly in appendix
68
Most important bioactive agents that carcinoid tumors secrete (3):
Serotonin
Histamine
Kinin peptides
69
Other important substances that carcinoid tumors secrete
Dopamine
Prostaglandins
Substance P
Gastrin
Somatostatin
70
Carcinoid tumor secreting bioactive substances - what happens?
Adrenergic stimulation -->release of serotonin into bloodstream -->metabolized to 5-HIAA (excreted in urine)
71
Marker for excess serotonin production in presence of carcinoid tumor
Elevated 5-HIAA in urine
>30 mg in 24 hour urine
normal is 3-15
72
Serotonin causes (BP)
vasoconstriction AND vasodilation
HTN and hypotension may occur
73
elevated serotonin causes (cardiac):
Inotropic and chronotropic cardiac effects
(release of NE)
74
Elevated serotonin GI (3)
Increased gut motility
Vomiting
secretion of water, sodium, chloride, potassium by small intestine
75
Elevated serotonin: other (3)
-Bronchospasm
-Hyperglycemia
-Prolonged emergence from anesthesia
76
Histamine and carcinoids - what type of carcinoid and what does it cause?
-most commonly seen with gastric carcinoids
responsible for bronchospasm and flushing
77
Carcinoid tumors and Kinens (bradykinin)
what happens when abnormal amounts of bradykinin are produced?
pathway for bradykinin removal is saturation = prolonged exaggerated response
78
What are the prolonged, exaggerated responses with large amounts of bradykinin?
-Profound vasomotor relaxation = severe hypotension
-flushing via nitric oxide synthesis
-Bronchospasm (especially in asthmatics and with concomitant heart disease)
79
Two of the most common signs of carcinoid syndrome are:
Flushing and diarrhea
80
Cardiac manifestations of cardiac carcinoid tumors
-fibrosis of endocardium primarily on R side of heart
81
Left sided lesions that occur with cardiac carcinoid tumors can occur with
pulmonary involvement or via left to right shunt (atrial septal defect, ventricular septal defect, patent foramen ovale)
82
Typical valvular lesions associated with carcinoids syndrome
Pulmonic stenosis
Tricuspid regurgitation
83
Carcinoid syndrome can occur with _______ and manifests as:
can occur with tumor manipulation and manifests as:
-episodic cutaneous flushing (kinins, histamine)
-diarrhea
84
Carcinoid tumor monitoring
a-line (labile BP)
CVP
85
Carcinoid tumor hypotension treatment
phenylephrine
avoid ephedrine to avoid beta adrenergic activation
*stoelting says avoid vasoactive drugs with hypotension.
real world: avoid ephedrine and epi
86
Carcinoid tumor hypertension treatment
-increase anesthetic depth
-increase octreotide
87
Octreotide adverse effect
QT prolongation
88
Carcinoid tumor bronchospasm treatment
-octreotide
-deepen inhaled anesthetic
89
Gastrin site of production
G cells in stomach
90
Gastrin stimulus
Food in stomach
91
Gastrin function
Increase gastric acid secretion
increase pepsinogen secretion
92
Secretin site of production
S sells, small intestine
93
Secretin Stimulus
acid in duodenum
94
Secretin function
-increase pancreatic bicarbonate secretion
-decrease gastrin secretion
95
Cholecystokinin site of production
I cells small intestine
96
Cholecystokinin stimulus
Food in duodenum
97
Cholecystokinin function
1. increase gallbladder contraction for bile release
2. Increase pancreatic enzyme secretion
3. decrease gastric emptying
98
Gastric inhibitor peptide site of production
K cells - small intestine
99
Gastric Inhibitory peptide stimulus
Food in duodenum
100
Gastric inhibitory peptide function
1. Increase insulin release
2. decrease gastric acid secretion
3. decrease gastric motility
101
Somatostatin site of production
D cells - pancreatic islet
stomach
small intestine
102
Somatostatin stimulus
Food in gut
gastrin
CCK
103
Somatostatin function
Decrease all GI function (enzyme and motility)
Universal "off" switch
104
Insulin secretion is inhibited by (3):
1. alpha adrenergic sympathetic stimulation
2. beta adrenergic sympathetic and cholinergic blockade
3. arterial hypoxemia, hypothermia, traumatic stress, surgical stress via a-adrenergic means
105
Insulin secretion is enhanced bye (3):
1. parasympathetic vagal stimulation
2. betta-2 adrenergic sympathetic activation
3. cholinergic drug administration
106
Common cause of acute pancreatitis
ETOH abuse
107
What is the MOA of triggering of acute pancreatitis?
Triggered by damage to the pancreatic acinar cells via obstruction of the pancreatic duct
i.e. gallstones
108
What medication is thought to induce spasm of the sphincter of Oddi?
Morphine
spasm exacerbates bile obstruction and stasis
109
Hallmark of acute pancreatitis
increased serum anylase
110
Important consideration in management of pancreatitis
Fluid resuscitation - internal and external fluid loss are huge in pancreatitis
111
ERCP positioning
prone or lateral
ERCP = endoscopic surgery to improve drainage or pancreatic duct
112
Malabsorption syndrome (what is it and how does it happen)
interferes with nutrient absorption in small intestine through mucosal disruption
113
Fat malabsorption interferes with the uptake of fat soluble vitamins:
vitamins A,D,E, K
114
Most common cause of pancreatic insufficiency
Chronic pancreatitis
115
Other causes of pancreatic insufficiency
Cystic fibrosis
fistulas
gallstones
ischemic enteritis
neoplastic disease processes
116
Maldigestion cause
failure of chemical functions of digestion that take place in intestinal lumen or order of the intestinal mucosa
most commonly seen with ETOH related chronic pancreatitis
117
With an upper GI bleed, when to hypotension and tachycardia occur
> 25% blood volume lost
118
Gastric Volume (mL) =
27 + 14.6 x CSA - [ 1.28 x age)
CSA = cross sectional area
age is in years
119
What conditions guarantee and RSI
1. uncontrolled GERD
2. Pregnancy (18-20 weeks)
3. Bowel obstruction
4. Trauma
5. Post partum (within 48 h rs)
120
When would you use succ for RSI?
1. taking GLP-1-agonist
2.Neuro monitoring
3. hiatal hernia
4. 15 year old female
5. trauma 3 years ago
121
When would you use Roc for RSI?
-MH hx
-Myasthenia gravis
-PChE deficiency
-Burns/trauma
-Child < 8 years old
122
Succ issue
avoid increase in potassium as succ increases potassium (burns/trauma)
123
Succ is a depolarizer or non depolarizer
depolarizer
124
Succ onset
30-60 seconds
125
Succ dose
0.5 - 1 mg/kg
126
Roc onset
1-2 min
127
Roc normal dose
0.6 mg/kg
128
Roc RSI dose
1.2 mg/kg (onset is 2 x as fast)
