GI Block Flashcards
The largest membrane in the body is what… and what kind of cells is it made up off
The peritoneum
And a layer of simple squamous cells
What organs are retroperitoneal
Kidneys, ascending and descending colon
Duodenum
And Head/ Body of pancreas ( not the tail)
What are the layers of the esophagus
Adventitia, Muscualris and mucosa
Muscularis is 1/3 skeletal muscle, 1/3 mixed, and 1/3 smooth muscle for superior to interior
Mucosa: smooth muscle, lamina propia, and Nonkeratinized Stratified squamous
Note the difference between the UES and the LES
UES: upper esophageal sphincter is skeletal muscle
LES: lower sphincter is smooth muscle
What is the 1st part of the small intestine
Duodenum
What are the 4 main regions of the stomach
Cardia, Fundus, Body, Pylorus
What are the cells in the gastric pit
Surface mucous cell, Mucous neck cells, Parietal cells (HCL and IF) , Chief cells (Pepsinogen, Gastric lipase) , G cells (Gastrin)
In the presence of histamine how do ACh and Gastrin react
They are secreted more, making histamine a synergistic component (hence H2 blockers)
What are the ducts of the pancreas
Pancreatic duct ( Duct of Wirsung): connects to the common bile duct and enters the duodenum and the “AMPULA of VATER” controlled by the sphincter of oddi
Duct of Santorini (accessory duct): connects to the duodenum superior to the ampulla of Vater
What are the cell types of the pancreas
Clusters of glandular Epithelial cells call acini
And pancreatic islets (langerhaans)
Start at the left hepatic duct and trace your way to the duodenum
Left hepatic combines with right hepatic to form the common hepatic which joins with the cystic duct to make the common bile duct with connects to the duct of Wirsung (pancreatic duct) to make the ampulla of Vater, that passes through the sphincter of oddi into the duodenum
Ph of pancreatic juices
7-8
What stops the action of Pepsid from the stomach
Pancreatic juices (pH)
What enzyme digests starch
Pancreatic amylase
What enzyme breaks down proteins
Trypsin, Chymotrypsin, Carboxypeptidase, Elastase
What is the principle enzyme that breaks down triglycerides
Pancreatic lipase
What divides the two lobes of the liver
Falciform ligament
What connects the falciform ligament to the umbilicus
Ligamentum teres
Where does the liver receive blood from
Hepatic artery 25% (O2)
Portal Vein 75%
What is the blood flow through the liver
Hepatic artery+portal vein Hepatic sinusoids Central vein Hepatic vein I. VC Right atrium
Where does bile come from
Hepatic lobules to bile canaliculi to bile ducts
What makes up the portal tríad
Bile duct, portal venue, portal artriole
What are the general functions of the liver
Carb and lipid and protein metabolism, synthesis of bile salts, activation of vitamin D, Metz of drugs and hormones, excretion of bilirubin
Storage of glycogen and fat vitamins, as well as copper and iron,
Phagocytosis
PH of Bile
7.6-8.6
What is the longest and shortest portion of the small intestine
Longest: ileum (6 ft)
Shortest: duodenum ( 10 inches)
What vitamins are produced in the large intestine
Vitamin K and biotin
What are the 4 regions of the large intestine
Cecum, colon, rectum, and anal canal
What is the pectinate line of the anal canal
Inferior most portion of the anal columns
Above this line is visceral innervation (sensitive to only stretch)
Below this line somatic innervation, sens. To pai, temp and touch
Important to hemorrhoid location
What is the definition of dyspepsia
Acute, chronic, or recurrent pain located in the upper abdomen
Clinically relevant > 1 month
What are the associated s/s of dyspepsia
Postprandial fullness Early satiation Anorexia Belching Nausea/vomiting Bloating Heartburn Regurgitation
Does dyspepsia= heartburn
No
What are the 2 types of dyspepsia
Organic: GI tract dysfunction, mediations, Pancreatic/biliary DOs, systemic conditions, PUD and GERD
Functional
What is the most common cause of chronic dyspepsia
Functional dyspepsia
What is the DO criteria for functional dyspepsia
Postprandial fullnes, early fullness, Epi gastric pain or burning
With no evidence of structural dz
What are the alarm features of dyspepsia
Unintentional weight loss New-onset dyspepsia after age 55 years Dysphagia Persistent vomiting Any overt gastrointestinal bleeding, hematemesis, or melena Family history of esophageal or gastric cancer Iron deficiency anemia Palpable abdominal mass or lymph node
What labs should be ordered in dyspepsia
H pylori
CBC
CMP
Thyroid panel
Others:
Celiac disease test
Stool for ova and parasites, guardia, fecal fat, or elastase
Ultrasound or CT ( pancreatic, biliary, Volvulus, or vascular dz)
Gastric emptying studies
What is the investigation of choice for dyspepsia
Upper endoscopy
What patients get an upper endoscopy
All patients over 60 with new onset of dyspepsia
All pts with alarm features
What is the most important risk factor for gastric cancer
H pylori
What are the 4 tests for H pylori
Invasive: Gastric mucosal biopsies
Non invasive: Fecal Antigen, Urea breath test, serology
What test is the initial DO for H pylori and to confirm eradication
Fecal antigen test
What is the Tx for H pylori
high resistance: PPI, Bismuth, Tetra, and metro
Low resistance: PPI, Clarytho, Amoxicilin, metro
What is the managment of function dyspepisa
Lifestyle changes ( smaller meals, food diary, quit smoking)
Antisecratory Tx x 4 weeks
Antidepressants
Metocloprimide
What is the brain stem vomiting center
Área póstrema, nucleus tractus solitarios, and central pattern generator
All within the medulla
Acute onset of nausea without Ab pain what is the DDx
Food poisoning, acute gastroenteritis, systemic illness
Acute onset of N/V with Ab pain, DDx?
Peritoneal irritation, acute gastric or intestinal obstruction, or pancreaticobiliary disease
Persistent N/V, DDx ?
Pregnancy, gastric outlet obstruction, gastroparesis, intestinal dysmotility, psychogenic disorders, and central nervous system or systemic disorders.
Vomitting immediately after meals, DDx?
Bulimia or psychogenic
What is the criteria for orthostatic HOTN
Orthostatic hypotension - the presence of at least one of the following within 3 min of standing:
Decrease in systolic blood pressure by ≥20 mm Hg
or
Decrease in diastolic blood pressure by ≥10 mm Hg
A HR increase of ≥30 bpm may suggest hypovolemia, independent of whether the patient meets criteria for orthostatic hypotension
What is Ondansetron
Seretonin 5-HT3 antagonists
ANTIEMETIC
What are promethazine and prochloperazine
Dopamine antagonists
ANITEMETICS
What are meclizine, dimenhydrinate, scopalamine, and diphenhydramine
Antihistamines
ANTIEMETICS
What is singultus
Hiccups
Causes of hiccups
Sudden excitement, emotion Gastric distention Esophageal obstruction Alcohol ingestion Sudden change in temperature
Persistent hiccups are a clue to
Persistent hiccups may be a sign of serious underlying pathology.
CNS – neoplasm, infection, trauma
Metabolic – uremia, hypocapnia
Chronic irritation of the vagus or phrenic nerve
Postoperative
Psychogenic
What is the managment of hiccups
Physical maneuvers: Teaspoon of dry sugar Holding breath/Valsalva Rebreathing Scaring
Consider medications if persistent >48 hrs
- PPI if GERD is present
- Baclofen, gabapentin, or metoclopramide
Surgical referral for ablation/stimulation of the phrenic nerve for refractory
What is eructation
Belching, burping
What is FODMAPs
Causes of flatus
Fermentable Oligosacharides Disaccharides Monosaccharides Polyps
What are the drugs to tx flatus
Alpha-d-galactosidase enzyme (Beano®)
Simethicone (Gas-X®)
Lactase enzyme (Lactaid®)
What is the definition of constipation
Decreased stool frequency
(fewer than three bowel movements [BM] per week)
with complaints of excessive straining, lower abdominal fullness, hard stools, feeling of incomplete evacuation, commonly associated with hardened feces or another underlying disorder.
Common causes of constipation
Dehydration, poor diet, poor habits, DM, hypothyroid, Cancer, Drugs, IBS
What is the constipation W-Up
Dullness to percussion in the lower quadrants (left)
DRE- obstruction and hard stool in rectal vault
CBC
CMP
Thyroid Panel
FOBT
Radiographs Endoscopy (colonoscopy or sigmoidoscopy)
What is the pharm managment of constipation
Pharmacotherapy:
Osmotic Laxative:
- Magnesium hydroxide (Milk of Magnesia, Epsom Salts)
- Polyethelyne glycol 3350 (Miralax)
- *Polyethelyne glycol (GoLYTELY)
- *Magnesium citrate
Stimulant Laxative: -Bisacodyl (Dulcolax) -Senna (ExLax) Stool Surfactants: -Docusate Sodium (Colace)
Enema:
Tap water
Saline (Fleet)
What is the managment to fecal Impaction
Initial treatment is directed at relieving the impaction with enemas (saline, mineral oil, or diatrizoate) or digital disruption of the impacted fecal material.
When should pts get referrals for constipation
Symptoms are refractory to treatments Patient has structural abnormality Evidence of obstruction Over age 50 or Alarm symptoms Referral for scope
What is the definition of diarrhea
Increased stool frequency (>3 BMs/day)
and/or
Loose/liquid stools
What is often the cause of non inflammatory diarrhea
Virus, sometime bacteria and rarely parasites
What is the time frame for acute vs chronic diarrhea
Acute is less than 2 weeks
Chronic is longer than 4 weeks
What is the criteria for persistent diarrhea
Lasting 2-4 weeks
What is the essential DO for acute non inflammatory diarrhea
Less than 2 weeks
Non bloody
Mild and self limited
Caused by a virus or non invasive bacteria
When should evaluation for Diarhea be performed
For severe cases or lasting longer than 7 days
What are the agents that can cause non inflammatory acute diarrhea
Viral (most common):
- Norovirus (50%)
- Rotavirus (children, older adults)
- Cytomegalovirus (AIDS)
Bacterial (less common):
- Clostridum perfringens, Bacillus cereus, Staphylococcus aureus
- Shiga toxin–producingEscherichia coli
- Vibrio choleraetoxin (causes the small intestinal cells to secrete, rather than absorb, fluid and electrolytes)
Parasites:
-Giardia, Cryptosporidium, Cyclospora, Cystoisospora belli
What is essential to DO acute inflamatory diarrhea
Less than 2 weeks
Bloody
Pus
Fever
What is the evaluation W-up for acute inflammatory diarrhea
Routine stool cultures ( e.coli 0h157)
C. Diff testing, ova and parasites
What is tenesmus
Rectal cramping seen in acute inflammatory diarrhea
What are the agents that curse acute inflammatory diarrhea
Salmonella (most common) Campylobacter Shigella Shiga toxin–producing Escherichia coli Enteroinvasive Escherichia coli Clostridium difficile (recent antibiotics) Nosocomial origin Yersinia Entamoeba histolytica (bloody diarrhea in patients who recently traveled to a developing country)
When is prompt eval of diarrhea warranted
Signs of inflammatory diarrhea:
- Fever
- WBC 15,000/mcL or more
- Bloody diarrhea
- Severe abdominal pain
- Profuse watery diarrhea and dehydration
- Frail older patients or nursing home residents
- Immunocompromised patients
- Exposure to antibiotics
- Hospital-acquired diarrhea (onset following at least 3 days of hospitalization)
- Systemic illness
How will fecal leukocytes be in non inflamatory diarrhea
Negative
How many samples are needed in ova and parasite testing
3
What is the test that is a marker of intestinal inflammation
Fecal lactoferrin
What are the anti motility agents used to tx acute diarrhea
Loperamide
Bismuth (good for travelers diarrhea)
When should ABX be used in the Tx of diarrhea
Patients with fever, abdominal pain, bloody diarrhea, or dysentery presumed due to Shigella
Patients who have recently traveled internationally with body temperatures 38.5 °C or higher and/or signs of sepsis
Immunocompromised patients with severe illness and bloody diarrhea
Patients with severe diarrhea in the context of hospitalization or antibiotic therapy (C dif)
What are the DOC for empiric diarrhea ABX Tx
Fluoroquinolones – drugs of choice:
- Ciprofloxacin 500 mg BID for 5-7 days
- Ofloxacin 400 mg BID for 5-7 days
- Levofloxacin 500 mg QD for 5-7 days
What are the drugs that are used to Tx travelers Diarhhea
Fluoroquinolones – 3 day courses
Not useful for travel to Southeast Asia
Azithromycin – 1000mg single dose
Rifaximin 200 mg TID x 3 days
ABX in diarrhea should only be used to Tx which agents
Shigellosis Cholera Extraintestinal salmonellosis Listeriosis Traveler’s diarrhea C difficile Giardiasis Amebiasis
When should a pt be admitted with diarrhea
Severe dehydration for intravenous fluids
Bloody diarrhea that is severe or worsening
Severe abdominal pain, worrisome for toxic colitis, inflammatory bowel disease, intestinal ischemia, or surgical abdomen.
Signs of severe infection or sepsis (temperature higher than 39.5°C, leukocytosis, rash).
Severe or worsening diarrhea in patients who are older than 70 years or immunocompromised.
Signs of hemolytic-uremic syndrome (acute kidney injury, thrombocytopenia, hemolytic anemia).
What is the first step in evaluating a pt with chronic diarrhea
Review their med list
What should be considered in all pts with chronic postprandial diarrhea
Carb malabsorption
How will fasting effect osmotic diarrhea?
Secretory diarrhea?
Osmotic : Stool volume decreases with fasting
Increased stool osmotic gap
Secretory: Increased intestinal secretion or decreased absorption
High volume, watery stool
Little to no change with fasting
Normal stool osmotic gap
What can cause secretory chronic diarrhea
Laxative abuse
Endocrine tumors
Bile salt malabsorption
What are the causes of chronic inflammatory diarrhea
Inflammatory Bowel Disease
- Crohn Disease
- Ulcerative Colitis
Microscopic Colitis
Malignancy
Radiation
A young adult with lower Ab pain and altered bowel habits, with out wt loss, nocural diarrhea, anemia or GI bleeding think?
IBS
What are the causes of chronic infectious diarrhea
Parasitic infections
Giardia, E histolytica, and Cyclospora
Intestinal nematodes
What is the W-up to chronic diarrhea
First exclude most common causes:
Medications, IBS, lactose intolerance
Evaluation directed at most likely etiology based on symptoms and history
Lab Tests:
CBC, Chem 17, LFT, Thyroid studies, ESR, CRP
Stool studies
Culture, Leukocytes, Lactoferrin, Occult blood, O&P, electrolytes
Colonoscopy ( r/o IBD and neoplasm)
24 hr stool collection
Referral to gastro
What is the anatomic landmark that separates upper and lower GI
Ligament of trietz
What defines Acute upper GI bleeding
Essentials of Diagnosis
-Hematemesis
-Varying degrees of hypovolemia
+/- Melena (may be hematochezia in massive bleed)
-Bleeding proximal to the Ligament of Treitz
What are the general causes of acute upper GI bleeding
PUD Portal Hypertension (esophageal varices) Mallory Weiss tears (alcohol abuse) Angioectasis Telangiectasis Neoplasms Erosive gastritis/ esophagitits
Boerhaave syndrome (rupture of esophagus)
What is the 1st and most important step in the managment of an acute upper GU bleed
Stable or unstable?
Unstable: SBP< 100
HR>100
What is the managment of unstable upper GI bleed
Start IV
- CBC, PT/INR, CMP, type and screen
- Fluid or Blood Replacement
- Start isotonic fluids
- 2-4 units PRBC
- NG Tube
May be helpful in initial assessment, aspiration of blood or coffee grounds confirmatory
Consider octreotide if patient has liver disease or portal hypertension
Reduces splanchnic blood flow and portal BP
What are the high risk factors for rebleeding in acute upper GI bleeds
Age > 60
Comorbid illnesses
SBP < 100 mmHg
Pulse > 100 bpm
Bright red blood in NG aspirate or upon rectal examination
Where do high risk pts with upper GI bleeds get sent to
ICU
What do all pts with acute upper GI bleeds get
EGD (endoscopy)
What is the pharm approach to acute upper GI bleed
PPI
Octreotide ( reduces portal BP and lowers rebleed RSK)
D/c NSAIDS
ABX if H. Pylori
What are the causes of lower GI bleeding
Anorectal Disease (MC mild) -Hemorrhoids, fissures, ulcers
Diverticulosis (MC severe)
-Painless, bright red blood, “large” volume
Inflammatory Bowel Disease
-Ulcerative Colitis, Crohn Disease
Infectious Colitis
Neoplasm
Angioectasias
-Commonly in older patients (> 70 yrs)
Ischemic Colitis
What is the causes of lower GI bleeds in pts less than 50
Anorectal Disease
Inflammatory Bowel Disease
Infectious Colitis
What are the likely causes of lower GI bleed in pts over 50
Diverticulosis
Malignancy
Angioectasias
Ischemic Colitis
What is the DDI with painful defecation
External hemorrhoids or anal fissures
What is the DDx with abdominal pain/ .cramps
IBD or colitis
What is the DDx with pts with lower GI bleeds yet painless
Internal hemorrhoids or diverticular bleeding
If the lower GI bleeding is a large volume thing
Diverticular bleeding
If the lower GI bleeding is low volume think
IBD, or hemorrhoids
What is an ominous sign in LGIB
Anemia- particularly If suspecting a neoplasm
What is the W- up/ .testing of LGIB
Exclude upper source ( NGT, EGD)
Colonoscopy- if large volume or older than 45
(Within 24 hrs if active bleed)
Anoscopy or sigmoidoscopy - if small volume or younger than 45
Technetium scal and angiography- if continued unstable or hematochezia
Capsule endoscopy
What is the Tx approach to Large volume LGIB
Therapeutic colonoscopy
-Vasoconstrictive injection, cautery, clips/bands
Intra-arterial embolization
Surgery
- Last resort
- Indicated if patient requires > 6 units of PRBC in 24 hrs or more than 10 units total
Where is obscure bleeding in the GI tract usually from
Small intestine
What is occult blood in the GI tract from
(positive result of fecal occult blood testing, usually in the setting of iron deficiency anemia)
What type of bleeding does a fecal immuniochemical test detect
Only LGIB
The presence of unexplained anemia or abnormal CBC think
Occult bleeding
If there is an occult GIB, you must investigate for a..
Neoplasm
Asymptomatic pt with incidental FOBT w/out anemia, gets what test
Colonoscopy
Symptomatic pt with +FOBT and or unexaplined anemia should get..
Upper Endoscopy AND Colonoscopy
IF the GI bleeding is bright red, what is the likely source
Left colon
If the GI bleeding is brown with streaks of red, what is the likely source
Rectosigmoid or anus
If the GI bleeding is maroon, what is the likely source
Small intestine ro right colon
If the GI bleeding is Black what is the likely source? N
Upper GI
What is the definition of ascites
The pathologic accumulation of fluid in the peritoneal cavity
What is the normal amount of fluid in the peritoneum
Men: none
Women -/+ 20 ml ( menestral dependent)
What is the most common cause of ascites
Portal hypertension
- hepatic congestion (CHF)
- liver dz (80%)
- hepatitis
Others: Hypoalbunima and Nephrotic syndrome
Chylous, pancreatic DO, bile ascites
Infections or Cancer
What two veins lead to the hepatic portal vein
Splenic and Superior Mesenteric
What is portal HTN
Pressure gradient between the portal vein and the IVC > 10 mmHg
What is the pt hz relevant to ascites
Alcohol, hepatic, and cancer
Fever with ascites suggests
Bacterial peritonitis
What are the prominent physical exam findings in Ascites
Hepatic enlargement, elevated JVP, and large adominal wall veins
W/ liver dz: muscle wasting and malnourishment
What is the physical exam test for ascites
Shifting Dulles test