Gastrointestinal Assessment Spring '24-2 Flashcards
1
Q
What are the main functions of the GI tract?
A
Motility, digestion, absorption, excretion, circulation
2
Q
What are the layers of the GI tract from outermost to innermost?
A
Serosa, longitudinal muscle, circular muscle, submucosa, mucosa
3
Q
What layers are within the mucosa of the GI tract?
A
Muscularis mucosae, lamina propria, epithelium
4
Q
What is the serosa in the GI tract?
A
Smooth membrane of thin connective tissue and cells
5
Q
How does the longitudinal muscle layer contribute to gut motility?
A
Shortens the length of the intestinal segment
6
Q
What is the function of the circular muscle layer in gut motility?
A
Decrease the diameter of the intestinal lumen
7
Q
How do the longitudinal and circular muscle layers work together in gut motility?
A
Propagate gut motility
8
Q
What is the innervation of the GI organs up to the proximal transverse colon?
A
Celiac plexus
9
Q
Where does the innervation of the descending colon and distal GI tract come from?
A
Inferior hypogastric plexus
10
Q
How can the celiac plexus be blocked?
A
Transcrural, intraoperative, endoscopic ultrasound-guided, peritoneal lavage
11
Q
Where does the myenteric plexus lie? What does the myenteric plexus regulate?
A
Between smooth muscle layers. It regulates mooth muscle
12
Q
What does the submucosal plexus do?
A
Transmits information to nervous systems
13
Q
What is the mucosa composed of?
A
Muscularis mucosa, lamina propria, immune cells, epithelium
14
Q
What is the function of the muscularis mucosa?
A
Move the villi
15
Q
What is found in the lamina propria?
A
Blood vessels & nerve endings
16
Q
What are some functions of the epithelium in the mucosa?
A
Sensing GI contents, secreting enzymes, absorbing nutrients, excreting waste
17
Q
What is the innervation of the GI tract?
A
Autonomic nervous system
18
Q
What are the components of the GI ANS?
A
Extrinsic SNS, Extrinsic PNS, Enteric NS
19
Q
What is the function of the extrinsic SNS in the GI tract?
A
Inhibitory, decreases GI motility
20
Q
What is the function of the extrinsic PNS in the GI tract?
A
Excitatory, activates GI motility
21
Q
What does the enteric nervous system control?
A
Motility, secretion, blood flow
22
Q
What is the enteric system comprised of?
A
Myenteric plexus and submucosal plexus
23
Q
What does the myenteric plexus control?
A
Motility
24
Q
What controls absorption, secretion, and mucosal blood flow?
A
Submucosal plexus
25
How do both plexuses respond to stimulation?
Sympathetic and parasympathetic
26
What is an Upper Gastrointestinal Endoscopy?
Endoscope inserted into upper GI tract
27
What areas does an upper GI endoscopy examine?
Esophagus, stomach, pylorus, duodenum
28
What are some challenges related to anesthesia in upper GI endoscopy?
Sharing airway with endoscopist
29
What are some challenges related to anesthesia in colonoscopy?
Dehydration due to bowel prep
30
What is High Resolution Manometry (HRM)?
Pressure catheter measures pressures along esophageal length
31
What is a common use of High Resolution Manometry?
Diagnose motility disorders
32
What is assessed in a GI series with ingested barium?
Swallowing function and GI transit
33
What is a Gastric emptying study?
Patient fasts, then consumes a meal with a radiotracer and undergoes imaging
34
What is the purpose of small intestine manometry?
Evaluates contractions and motility
35
What are the three periods during which contractions are evaluated in small intestine manometry?
Fasting, during a meal, post-prandial
36
What are abnormal results in small intestine manometry grouped into?
Myopathic and/or neuropathic causes
37
What does a lower GI series involve? How does this help in a lower GI series?
Barium enema administration. This Outlines the intestines for radiograph visibility
38
What are the three groups that esophageal diseases are grouped into?
Anatomical, Mechanical, Neurologic
39
What are examples of anatomical causes of esophageal diseases?
Diverticula, Hiatal hernia, Chronic acid reflux
40
What are examples of mechanical causes of esophageal diseases?
Achalasia, Esophageal spasms, Hypertensive LES
41
What can cause neurologic causes of esophageal diseases?
Neurologic disorders like stroke, vagotomy, hormone deficiencies
42
What are the most common symptoms of esophageal disease?
Dysphagia, heartburn, GERD
43
What is dysphagia?
Difficulty swallowing
44
What are the two types of dysphagia?
Oropharyngeal, esophageal
45
How is esophageal dysmotility characterized?
Symptoms occur with both liquids & solids
46
What type of dysphagia is characterized by symptoms only occurring with solid food?
Mechanical esophageal dysphagia
47
What is gastroesophageal reflux disease (GERD)?
Effortless return of gastric contents into pharynx
48
What are the common symptoms of GERD?
Heartburn, nausea, 'lump in throat'
49
What is Achalasia characterized by?
Outflow obstruction and inadequate LES tone
50
What could be the cause of Achalasia?
Loss of ganglionic cells of esophageal myenteric plexus
51
What are the symptoms of Achalasia?
Dysphagia, regurgitation, heartburn, chest pain
52
How is Achalasia diagnosed?
Esophageal manometry and/or esophagram
53
What are the three classes of Achalasia?
Type 1, Type 2, Type 3
54
What are the treatments for esophageal disease Achalasia?
Medications, Endoscopic botox injections, Pneumatic dilation, Laparoscopic Hellar Myotomy, Peri-oral endoscopic myotomy (POEM), Esophagectomy
55
Which treatment is considered the most effective nonsurgical option for Achalasia?
Pneumatic dilation
56
What is the best surgical treatment for Achalasia?
Laparoscopic Hellar Myotomy
57
What does POEM stand for in the context of Achalasia treatment?
Peri-oral endoscopic myotomy
58
When is esophagectomy considered as a treatment for Achalasia?
Only in the most advanced disease states
59
What is indicated for patients with Achalasia at increased risk for aspiration?
RSI or awake intubation
60
What are diffuse esophageal spasms?
Spasms in distal esophagus; common in elderly
61
How are diffuse esophageal spasms diagnosed?
Dx on esophagram
62
What is a characteristic symptom of pharyngoesophageal diverticulum?
Bad breath from food retention
63
What is the recommended treatment for diffuse esophageal spasms?
NTG, antidepressants, PD-I's
64
Why are all types of esophageal diverticula considered aspiration risks?
Removal of particles and RSI indicated
65
What is a hiatal hernia?
Stomach herniation into thoracic cavity
66
What are some causes of hiatal hernia?
Weakening of anchors of GE junction to diaphragm
67
What are common symptoms associated with hiatal hernia?
May be asymptomatic; often linked to GERD
68
What is the incidence rate of esophageal cancer in the US?
4-5/100,000 people
69
What are common presentations of esophageal cancer?
Progressive dysphagia and weight loss
70
Why is the survival rate of esophageal cancer poor?
Abundant lymphatics leading to lymph node metastasis
71
What is the most common type of esophageal cancer?
Adenocarcinomas located in lower esophagus
72
What risk factors are associated with adenocarcinomas of the esophagus?
GERD, Barretts, Obesity
73
Which type of esophageal cancer accounts for the rest?
Squamous cell carcinoma
74
What are the different types of esophagectomy approaches?
Transthoracic, transhiatal, minimally invasive
75
What is a risk associated with esophagectomy related to the recurrent laryngeal nerve?
High risk of injury, 40% resolve spontaneously
76
Why are patients often malnourished preoperatively and for months after esophagectomy?
Pts often malnourished
77
What complications may present in patients with a history of chemotherapy or radiation who undergo esophagectomy?
Pancytopenia & dehydration
78
What is a significant risk for post-esophagectomy patients?
High aspiration risk for life
79
What is GERD associated with in terms of gastric functions?
Incompetence of the gastro-esophageal junction
80
What are the primary symptoms of GERD?
Heartburn, dysphagia, mucosal injury
81
What percentage of adults suffer from GERD?
15%
82
What types of substances are refluxed in GERD?
HCl, pepsin, pancreatic enzymes, bile
83
What is bile reflux related to in GERD patients?
Bile reflux is associated with Barrett metaplasia & adenocarcinoma
84
What are the three mechanisms leading to GE incompetence in GERD?
Transient LES relaxation, LES hypotension, Autonomic dysfunction of GE junction
85
What is the average LES pressure in patients with GERD?
13 mmHg
86
What is the normal LES pressure?
29 mmHg
87
What are the treatment options for GERD?
Avoid trigger foods, use Antacids, H2 blockers, PPIs, consider surgery
88
What are some preoperative interventions for GERD?
Cimetidine, Ranitidine, PPIs, Sodium Citrate, Metoclopramide
89
What is Metoclopramide used for in GERD patients?
Gastrokinetic; often reserved for diabetics, obese, pregnant
90
What precautions should be considered for GERD patients?
Aspiration precautions!
91
When is RSI indicated in GERD patients?
RSI indicated. Cricoid pressure has become controversial
92
What factors can increase the risk of intraoperative aspiration?
Emergent surgery, Full Stomach, Difficult airway, Inadequate anesthesia depth
93
Which conditions or situations can contribute to a higher risk of intraoperative aspiration?
Autonomic Neuropathy, Gastroparesis, DM, Pregnancy
94
What are some other factors that can increase the risk of intraoperative aspiration?
Lithotomy, ↑ Intraabdominal pressure, Severe Illness, Morbid Obesity
95
What is the shape of the stomach?
J-shaped
96
What are the main functions of the stomach?
Reservoir for food, mixes/breaks down food, forms chyme, slows emptying into the small intestine
97
To what size must solids be broken down before entering the duodenum?
1-2 mm particles
98
What type of regulation controls the motility of the stomach?
Intrinsic and extrinsic neural regulation
99
What effect does parasympathetic stimulation have on stomach contractions?
Increases number and force
100
Which nerve is involved in parasympathetic stimulation of the stomach?
Vagus nerve
101
What does sympathetic stimulation do to stomach contractions?
Inhibits them
102
Which nerve is involved in sympathetic stimulation of the stomach?
Splanchnic nerve
103
What substances increase the strength and frequency of stomach contractions?
Gastrin & motilin
104
What substance inhibits stomach contractions?
Gastric inhibitory peptide
105
What is the most common cause of non-variceal upper GI bleeding?
Peptic Ulcer Disease
106
What is the lifetime prevalence of peptic ulcer disease in women? What is the lifetime prevalence in men?
Women 10%
Men 12%
107
How many deaths per year are attributed to peptic ulcer disease?
15,000
108
What is commonly seen with peptic ulcer disease?
Helicobacter Pylori
109
What are the symptoms of peptic ulcer disease?
burning epigastric pain exacerbated w/fasting and improved w/meals
110
What is the risk of perforation in those who do not receive treatment for peptic ulcer disease?
10%
111
What can occur in perforation of a peptic ulcer?
sudden/severe epigastric pain c/b acidic secretions into peritoneum
112
What is the main cause of mortality in peptic ulcer disease cases?
shock or perforation >48h
113
What are the potential onsets for Gastric Outlet Obstruction?
Acute or slow
114
What can cause acute obstructions in Gastric Outlet Obstruction?
Edema & inflammation in pyloric channel
115
Symptoms of Pyloric Obstruction include:
Recurrent vomiting, dehydration, hyperchloremic alkalosis
116
Initial treatment options for Gastric Outlet Obstruction
NGT, IV hydration
117
Usual resolution time for Gastric Outlet Obstruction with initial treatment
72h
118
What can repetitive ulceration & scarring lead to in Gastric Outlet Obstruction?
Fixed-stenosis and chronic obstruction
119
What are the common causes of gastric ulcers?
Excessive NSAIDs, H. Pylori, ETOH
120
What is the treatment for gastric ulcers?
Antacids, H2 blockers, PPIs
121
How is H. Pylori infection usually treated in the context of gastric ulcers?
Triple therapy (2 abx + PPI) x 14 days
122
What is Zollinger-Ellison Syndrome?
Non B cell islet tumor of pancreas causing gastrin hypersecretion
123
How does gastrin contribute to Zollinger-Ellison Syndrome?
Stimulates gastric acid secretion with absent feedback loop
124
What are the symptoms of Zollinger-Ellison Syndrome?
Peptic ulcer dz, erosive esophagitis, diarrhea
125
What is the treatment for Zollinger-Ellison Syndrome?
PPIs and surgical resection of gastrinoma
126
What percentage of patients with gastrinomas are metastatic at the time of diagnosis?
Up to 50%
127
How do patients with Zollinger-Ellison Syndrome present in terms of gender and age?
Males more than females; most common between ages 30-50
128
What is the major function of the small intestine?
To circulate the contents and expose them to the mucosal wall to maximize absorption of water, nutrients, and vitamins.
129
How does small intestinal motility aid digestion?
It mixes contents of the stomach with digestive enzymes, reducing particle size and increasing solubility.
130
What mechanism does the small intestine use to ensure ample absorption time?
Segmentation
131
What controls segmentation in the small intestine?
Mainly the enteric nervous system with modulation by the extrinsic nervous system.
132
What are the two muscle layers of the small intestine involved in segmentation?
The circular and longitudinal muscle layers.
133
What are some reversible causes of small bowel dysmotility?
mechanical obstruction, bacterial overgrowth, ileus
134
What are some nonreversible causes of small bowel dysmotility?
structural or neuropathic
135
What are examples of structural causes of nonreversible small bowel dysmotility?
scleroderma, connective tissue disorders, IBD
136
What are examples of neuropathic causes of nonreversible small bowel dysmotility?
pseudo-obstruction
137
What symptoms can neuropathic causes of small bowel dysmotility lead to?
bloating, nausea, vomiting, abdominal pain
138
What is the function of the large intestine?
Acts as a reservoir and extracts electrolytes/water
139
How does distention of the ileum affect the ileocecal valve?
Relaxes to allow intestinal contents into the colon
140
What role do giant migrating complexes play in the large intestine?
Produce mass movements
141
What is the primary symptom of colonic dysmotility?
Altered bowel habits and/or intermittent cramping
142
What are the most common diseases associated with colonic dysmotility?
IBS and IBD
143
What are the Rome II criteria for IBS?
Abdominal discomfort + 2 of the following: defecation relieves discomfort, pain with abnormal frequency, pain with change in stool form
144
What is the effect of inflammation on colonic contractions in IBD?
Suppression
145
How do giant migrating complexes contribute to hemorrhage and erosion in IBD?
Increased frequency and pressure compress inflamed mucosa
146
What is the second most common inflammatory disorder?
IBD
147
What are the two main types of IBD?
UC & Crohn's
148
What is the incidence of IBD?
18:100,000 ppl
149
What are the symptoms of Ulcerative Colitis?
Diarrhea, rectal bleeding, crampy abdominal pain, N/V, fever, weight loss
150
What are some laboratory findings in UC?
↑plts, ↑ESR, ↓H&H, ↓albumin
151
When does hemorrhage in UC warrant surgical colectomy?
6+ units blood in 24-48 hrs
152
What is toxic megacolon triggered by?
E-lyte disturbances
153
What percentage of UC cases require colectomy?
Around half
154
What is the mortality rate for colon perforation in UC?
15%
155
What is the most common site of Crohn’s Disease?
Terminal ilium
156
What are the two patterns of disease in Crohn’s Disease?
Penetrating-fistulous, obstructing
157
What are common symptoms of Crohn’s Disease?
Weight loss, fear of eating, anorexia, diarrhea
158
What happens due to persistent inflammation in Crohn’s Disease?
Fibrous narrowing & stricture formation
159
What does extensive inflammation in Crohn’s Disease lead to?
Malabsorption & steatorrhea
160
How can Crohn's Disease affect areas outside the bowel?
Arthritis, dermatitis, kidney stones
161
What is the mainstay treatment for IBD?
5-Acetylsalicylic acid (5-ASA)
162
What types of medications are used during IBD flares?
PO/IV Glucocorticoids
163
Name two antibiotics used in IBD treatment.
Rifaximin, Flagyl, Cipro
164
What type of drugs are used as a last resort in IBD treatment before surgery?
Purine analogues
165
When is surgery considered in IBD treatment?
Last resort
166
How much of the small intestine can be safely resected to avoid short bowel syndrome?
<1/2 length
167
What is the consequence of resecting >2/3 of the small intestine?
Short bowel syndrome, requiring TPN
168
What is the origin of most carcinoid tumors?
GI tract
169
What are some substances secreted by carcinoid tumors?
Peptides, vasoactive substances
170
What symptoms may occur in carcinoid syndrome?
Flushing, diarrhea, HTN/HoTN, bronchoconstriction
171
How is carcinoid syndrome diagnosed?
Urinary or plasma serotonin levels
172
What is a treatment option for carcinoid tumors?
Avoid serotonin-triggers, control diarrhea
173
What should be given preoperatively for carcinoid tumors to attenuate hemodynamic changes?
Octreotide
174
What is acute pancreatitis?
Inflammatory disorder of the pancreas
175
What are the common causes of acute pancreatitis?
Gallstones and alcohol abuse
176
How does alcoholism contribute to the increased incidence of acute pancreatitis?
Likely due to increased alcoholism
177
How can pancreatitis be triggered?
Failure of autodigestion prevention mechanisms
178
What obstructs the ampulla of Vater in pancreatitis?
Gallstones
179
What are the symptoms of Acute Pancreatitis?
excruciating epigastric pain, N/V, abd distention, steatorrhea, ileus, fever, tachycardia, HoTN
180
What are the hallmark labs seen in Acute Pancreatitis?
↑serum amylase & lipase
181
What imaging modalities are used in Acute Pancreatitis?
contrast CT or MRI, endoscopic US (EUS)
182
What are the complications of Acute Pancreatitis?
shock, ARDS, renal failure, necrotic pancreatic abscess
183
What is the treatment for Acute Pancreatitis?
Aggressive IVF, NPO, enteral feeding, opioids
184
What is the preferred feeding method over TPN in Acute Pancreatitis?
enteral feeding
185
What are the interventions in Endoscopic-retrograde cholangiopancreatography (ERCP)?
stone removal, stent placement, sphincterotomy, hemostasis
186
What percentage of blood loss will lead to hypotension and tachycardia?
>25%
187
What does melena indicate about the location of the bleed?
Above the cecum
188
What is the usual indication of orthostatic hypotension in GI bleeding?
HCT <30%
189
What is typically elevated in the blood due to absorbed nitrogen in upper GI bleeding?
BUN >40 mg/dL
190
What is the diagnostic/therapeutic procedure of choice for upper GI bleeding?
EGD
191
What is the last resort for uncontrolled variceal bleeding?
Mechanical balloon tamponade
192
What are some causes of lower GI bleeding?
Diverticulosis, tumors, colitis
193
What procedure is performed as soon as the patient is hemodynamically stable in lower GI bleeding?
Unprepped sigmoidoscopy
194
When is a colonoscopy performed in lower GI bleeding?
If patient can tolerate prep
195
What is the next step if there is persistent bleeding in lower GI bleeding cases?
Angiography and embolic therapy
196
What is adynamic ileus?
Massive dilation of colon without obstruction
197
What are the causes of adynamic ileus?
Electrolyte disorders, immobility, narcotics, anticholinergics
198
How is adynamic ileus treated?
Restore electrolyte balance, hydrate, mobilize, suction, enemas
199
What is the effect of neostigmine in adynamic ileus?
Produces immediate results in 80-90%
200
What can happen if adynamic ileus is left untreated?
Ischemia and perforation
201
How does anxiety levels in patients impact GI activity preoperatively?
Higher anxiety = higher inhibition of GI activity
202
What effect do volatile anesthetics have on GI activity?
Depress activity in stomach, small intestine, and colon
203
Which part of the GI tract is the first to recover postoperatively?
Small intestine
204
What can volatile agents coupled with sympathetic nervous system hyperactivity do to GI function?
Inhibit GI function and motility
205
What is the effect of nitrous oxide on gas-containing cavities?
Diffuses faster than nitrogen
206
When should nitrous oxide be avoided?
Lengthy abdominal surgeries or distended bowel
207
How do neuromuscular blockers (NMBs) affect GI motility?
Remains intact
208
What effect does Neostigmine have on bowel peristalsis?
Increase PNS activity and bowel peristalsis
209
How do anticholinergic medications counteract the bradycardia associated with neostigmine?
By partially offsetting cholinergic activity
210
Does Sugammadex have any effect on motility?
No
211
What are the effects of opioids on the GI system?
Reduced motility, constipation, delayed gastric emptying
212
Where are the peripheral mu-opioid receptors located in the GI system?
Myenteric and submucosal plexuses
213
What adverse events can result from opioid use in the GI system?
Nausea, anorexia, delayed digestion
214
What are the layers of the GI tract wall from outermost to innermost?
Serosa, longitudinal muscle, circular muscle, submucosa, mucosa
215
Which nervous system innervates the GI tract and what are its components?
Autonomic nervous system; SNS, PNS
216
What are the two primary movements within and along the GI tract?
Mixing and propulsive movements
217
How can anesthesia medications affect GI function?
Alter mechanisms
218
What adverse effect do opioids have on the bowel?
Decrease GI function
219
What conditions can be induced by hemodynamic changes and bowel manipulation?
Ileus, inflammatory states, mesenteric ischemia
