FES Flashcards
How many fiber optic fiber bundles are there?
Their functions?
How thick are they?
2.
One to deliver the light and one to transmit the image from the organ back to the viewer
8-10 micrometer
What is one disadvantage of the flexible fiber optic endoscope?
Fragility of the fibers. When an individual fiber breaks, you get dark spots
Fiber optics are now only used for what kind of scopes?
Scopes that require small diameter like bronch or choledoschoscope. No longer used in standard GI scopes
How is modern video endoscopy different from the fiber optic scopes?
Light is delivered via fiber optic.
But the viewing fiber optic is replaced with a charge-coupled device (CCD) chip based camera at the tip of the endoscope
What are the two possible sources of light
Xenon Arc
Halogen filled tungsten filament lamp
How wide are the instrument channels?
2-4.2mm
The umbilical cable contains connectors for what things?
Air insufflation, suction, water irrigation
Why not use saline for water bottle connecting to the scope?
May crystallize in the channel. Use sterile water
What is the advantage of disinfecting the scope with gluteraldehyde as opposed to ethylene oxide?
Ethylene oxide needs overnight cycle. Gluteraldehyde doesn’t.
What is the most common complication during colonoscopy?
Hypoxia (5.6%)
Hypotension (1.2%)
Bradycardia (0.8%)
Arrhythmia (0.1%)
What % of post-colonoscopy perforation needs an operation?
~50%
What is the incidence of post-colonoscopy perforation?
0.07%
What is the mortality rate of colonoscopy?
0.007%
What are the most common upper scope complications?
Hypoxia (up to 70%)
What is the incidence of perforation after upper endoscopy?
What is the mortality rate of upper endoscopy?
0.03% incidence
Mortality: 0.001%
Isoosmotic vs. hyperosmotic prep
Which one is better tolerated and more likely to be taken completely?
Which one is safe to use for pts who have electrolyte imbalance, liver disease, CHF, or renal failure?
Hyperosmotic more likely to be taken completely because it requires ingestion of only a small amount.
Isoosmotic prep is safe for liver disease, renal disease, etc
What is a potential side effect of sodium phosphate prep?
Nephrocalcinosis
Is magnesium citrate isoosmotic or hyperosmotic?
It also releases what hormone?
Hyperosmotic
Causes CCK release. Also promotes intestinal motility
Sodium phosphate prep might cause what electrolyte abnormality?
Hyperphos
Hypokalemia
What is the incidence of bacterial endocarditis during upper GI and colonoscopy?
4.4%
Which endoscopic procedure is associated with the highest risk of bacteremia?
Esophageal stricture dilation & sclerotherapy for esophageal varices
Risk of major pulmonary embolism in pts with mechanical heart valves in the absence of anticoagulation is what?
What is it with anticoagulation?
What about pts with AFib with no valvular disease without AC?
4 per 100 person-years without AC
2.2 with AC
5-7% for AFib alone
What are the 4 stages of sedation?
Mild, moderate, deep, general
What are the 2 most effective methods of identifying hypoventilation?
Side channel end tidal CO2
Transcutaneous CO2
What is MOAA?
The scale goes from what to what?
Modified observers assessment of awareness
0: doesn’t respond to noxious stimulation
1: doesn’t respond to mild stimulus
2: responds only to mild stimulus
3: responds only to loud voice
4: lethargic response to voice
5: fully responds
What’s the usual starting dose of versed?
0.5 - 2 mg IV or 0.05 to 0.1 mg/kg given as a bolus
What’s the onset of action of versed?
Allow how many minutes after giving a dose before dosing the next one?
3-5 minutes
Wait at least 2 min before redosing
Does flumazenil decrease time to discharge?
Usually not. Only when pt was given 0.09mg/kg of versed
Starting dose of flumazenil. How to titrate
Start with 1mg IV and titrate by 0.2mg to effect
How to dose fentanyl.
What’s the half life?
On avg 50-100 ug
Half life: 2-4hrs
What’s the usual starting dose of narcan?
0.4mg IV, repeating as necessary up to 2mg.
What is the reversal agent for propofol?
There is none
Propofolnis contraindicated in patients with what,m
Hypersensitivity to eggs or soybeans
Does distraction during colonoscopy decrease the need for sedatives?
When auditory and visual distractions are used together, yes
What is the role of nitrous oxide with colonoscopy?
Pts have more pain, tolerates the procedure less well, less satisfiee
Preceded vs. Fentanyl/versed?
Less effective compared to fentanyl/versed
What is the diameter of a small caliber scope?
Can this scope biopsy things?
3-6mm
Yes
What is the maximum amount of sprayed lidocaine you can use?
200mg
What are some negative effects associated with small caliber endoscopy?
Contraindication to SCE?
Vagal stimulation -> hypotension, hypoxia. Epistaxis
Coagulopathy, prior trauma to nasopharynx
What’s the half life of naloxone vs. fentanyl?
Naloxone: 1 - 1.5 hrs
Fentanyl: 2 - 4 hrs
Upper endoscopy surveillance:
Familial polyposis
Barrett’s esophagus
Esophageal varices
Esophageal/gastric ulcers
Pernicious anemia
Familial polyposis: 1-2 years
Barrett’s:
Low risk: every 2 yrs
High risk: 6mo-1yr
Esophageal varices: every 6-8 weeks
Esophageal/gastric ulcers: every 6 weeks until healed
Pernicious anemia: single endoscopy, no followup
Correct or positioning for upper endoscopy.
When would you do right side down?
Left side down, head slightly elevated
Right side down: acute UGI bleed. When left side down the blood collects in the fundus. Right side down will empty the blood
Upon reaching the sharp turn of the superior angle of the duodenum what should you do with the scope?
Dial up and right
Twist the shaft clockwise
Does bite block help or hurt airway?
It acts as a reverse jaw thrust. Higher risk of airway obstruction
HNPCC accounts for what % of colon cancers?
HNPCC develops cancer how many years earlier than the general public
What is the screening guideline for HNPCC?
6%
20 years
Begin at age 20-25 or 10 years earlier than the youngest agree of CRCA. Repeat every 1-2 years
Colonoscopy should be done how soon after colon resection:
1) if the pt had a pre-op colonoscopy?
2) if the pt didn’t have a pre-op colonoscopy?
(+) pre-op scope: 1-2 years post-op
(-) pre-op scope: 3 months post-op
For colonoscopy, the endoscopist stands on the patient’s (left/right)
Length of normal colonoscope
Length of a flexible signoidoscope
The patient’s right
Colonoscope: 130-160cm
Flex sig: 70cm
What can you do if the angle of the flexure is too acute?
Turn the pt on their back or to the right side
What is the incidence of polyps among ppl undergoing screening endoscopy?
What’s the size cutoff for small vs. large polyp?
~ 30%
1cm
(T/F) lipomas found during colonoscopy should be biopsied
What sign is associated with lipomas
False
Pillow sign (soft and spongy indentation when palpating using biopsy forceps)
What is the reported complication rate for
Diagnostic colonoscopy?
Polypectomy?
What is the mortality of colonoscopy?
Dx colonoscope: 1:1500
Polypectomy: 1:100
1/10,000
What are the causes of early endoscopic bleeding vs. late bleeding
Early: scope trauma, inadequate control of a bleeding source
Late: 1-2 weeks after hot biopsy or snare polypectomy
ERCP in cardiopulmonary instability or shock
In pregnant pt
Coagulopathic pts
Shock: may be of benefit if cholangitis
Pregnant: temporizing measure until completion of pregnancy
Coagulopathic: stent without sohincterotomy
What is brush biopsy’s cancer detection rate?
Needle aspiration?
Brush: 20-60%
Needle aspiration: 6-30%
Endoscopic sphincterotomy. Apply gentle pressure with the cutting wire towards (what clock) position. Continue the sphincterotomy until (what) portion of the bike duct is cut. Blended current with cutting and coagulation settings of (what) J are commonly used. Balloon dilation is associated with (higher/lower) rates of ERCP pancreatitis
11’oclock position
Intramural portion of the bile duct cut
15-20J
Dilation: higher rates of pancreatitis
How long do plastic CBD stents stay open?
What do you need to do when that time is almost up? Because why?
How long can pancreatic stents stay in? Why?
How long can nasobiliary tubes stay?
What is SEMS? better or worse patency rate? When are they used generally?
3-6 months.
You gotta remove or exchange the stent. bc if stents are clogged then they can get cholangitis
Pancreatic stents can stay in for ~3 weeks. If left longer, can cause ductal damage
Nasobiliary tubes are long plastic catheters similar to my tubes. Traversing the papilla into the biliary tree. Can be left in for several days. Does not require endoscopy for removal
Self Expanding Metal Stents. Longer patency rate. Usually used for malignant obstructions. No further intervention may be needed for the patient’s lifetime
When should ppl stop Coumadin or antiplatelets before ERCP?
Coumadin: 5 days + heparin/lovenox then stop heparin a day before
Antiplatelets: 10 days prior and not restart 5-7 days if sphincterotomy performed
Pt positioning for ERCP
If doing through duodenum is difficult what can you do?
Endoscopy cart is placed on which side of the pt?
Prone position, head turned towards right shoulder
Left lateral decubitus then switch to prone once the endoscope passed the pylorus
Supine is much harder
Endoscopy cart on the right side of the pt
Which part of upper scope is very painful for the pt and therefore you should try to complete as fast as possible?
In order to advance the scope across the pylorus and into the duodenum you must place the pylorus almost completely out of view along the (what)o’clock position
The major papilla is usually found in the medial aspect of the second portion of the duodenum. It will appear at the (what) o’clock position on the monitor?
Traversing the greater curvature because the excess looping is very painful
6 o’clock
1-2 o’clock position
For selective pancreatic cannulation, direct the sphincterotomy towards the (what) o’clock position
For selective biliary cannulation, direct the sphincterotomy towards (what) o’clock position
Pancreatic: 1-3 o’clock
Biliary: 11-12 o’clock
Incidence of post ERCP pancreatitis
3-5%
What is post-ERCP pancreatitis defined as?
How to decrease pancreatitis
Increased abd pain
Serum AMYLASE x3 above normal
Requires hospitalization
Limit contrast injected into pancreatic duct
ERCP is performed with a side viewing scope. When is a front viewing scope useful?
Duodenal stricture
Concentration of epinephrine for submucosal injection
Two mechanism submucosal injection works
How much can you inject?
(T/F) submucosal injections have associations with both perforation and stricture
1:10,000
Create tamponade, vasospasm of the feeding vessels
0.5-1cc at a time up to 10cc
T
Band ligation. What complications can be seen after band ligating esophageal varices?
Compared to sclerotherapy, band ligation has a (high/lower) complication rate.
What is the main disadvantage of band ligation?
Ulcers and stricture
Lower complication rate compared to sclerotherapy.
Main disadvantage: band ligating device cap can impair visualization
When are endoscopic clips useful? After what failed?
Endoscopic clips have (higher/lower) success rate compared to other hemostatic techniques
After thermal energy failed or too dangerous
Lower success rate due to difficulty with application
Monopolar vs. Bipolar cautery
Which one has higher risk of full thickness enteric injury?
Vessels up to what diameter are typically well controlled with cautery?
Monopolar has higher risk for full thickness enteric injury
Vessels up to 2mm
How is argon plasma coagulation different from electric cautery?
Ionized argon gas. Does not adhere to the probe. So the clot is not likely to be displaced on probe withdrawal. Also doesn’t have the tamponade effect. Used when deeper thermal injury leading to perforation is a high concern
Sessile polypectomy.
Why use hypertonic saline or hyaluronic acid?
Slows the redistribution/absorption of the injectate.
Inject at the proximal end of the colon and at the distal end of the foregut. This causes the lesion to be raised toward the endoscopist’s vision
For lesions > (what size) piecemeal excision can be used.
Piecemeal polypectomy is not a good idea in which portion of the bowel? Why?
> 2-2.5cm
Not good in cecum because wall is thin and may perforate
Most significant experience with mucosal resection has been in the management of what lesion?
Early gastric cancer
What diameter channel is needed to use large biopsy forceps?
3.5mm
What does lugol solution and methylene blue stain?
Lugol (1-2%) - stains glycogen containing normal esophageal squamous mucosal cell
Methylene blue (0.5-1%) - taken up by intestinal absorptive epithelium
Useful for identifying areas of intestinal metaplasia and focal carcinoma
What is the depth of coagulation of argon plasma coagulation?
2mm
Absolute contraindication for PEG or PEJ?
Removal of tubes within how many hours still require surgical closure?
Poorly controlled or massive ascites -> leak of ascietes or infection of ascites
96hrs
What are the three forms of bougies?
Stricture in general shouldn’t be dilated more than how many times?
For esophageal dilation, what bougie size usually relieve symptoms?
Blunt tipped (Hurst)
Tapered-tip (Maloney)
Wire-guided (Savary)
Three successive french sizes
40Fr is usually enough for esophagus
Balloon dilation for achalasia has perforate rate of what %?
2-3%
Plastic stents have (higher/lower) perforation rate than self Expanding stents
Lower with self Expanding stents
Rigid scope vs. flex scope for esophageal foreign body
Rigid: can use more rigid, large instruments
Flex is often successful, less prone to perforation.
Why is tattooing not very feasible for gastric lesions?
Thickness of the gastric muscular layer and the rapid diffusion of eyes within the gastric wall
