Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MRS211 > GIT > Flashcards

GIT Flashcards

1
Q

What is an acute lower gastro-intestinal haemorrhage (LGIH)?

A
  • abnormal intraluminal blood loss from a source distal to the ligament of Treitz (between the jejunum and duodenum)
  • acute haemorrhage is continuous, gross bleeding from the rectum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the annual incidence of hospitalisations for LGIH?

A
  • 22.0/ 100 000 of the general population
  • 20.5/ 100 000 of those already hospitalised
  • 24.2/ 100 000 males
  • 17.2/ 100 000 females
  • Incidence increases with age
  • 1.0/ 100 000 of 20-29 year old
  • 205.3/ 100 000 for those over 79 years
  • Bleeding rate increases with age and in males
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the most common causes of major LGIH

A
  • Diverticular disease

- Angiodysplasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are some less common causes of major LGIH

A
  • Ischemia
  • Neoplasia
  • Inflammatory bowel disease
  • Haemophilia
  • Perianal disease
  • Aorta-enteric fistula
  • Solitary rectal ulcer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the most common causes of minor LGIH

A
  • Haemorrhoids
  • Fissures
  • Perianal disease
  • Proctitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the most common causes of major LGIH

A
  • Neoplasia
  • Ischemic bowel disease
  • Infectious colitis
  • Radiation colitis
  • Angiodysplasia
  • Ischemia
  • Rectal ulcer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is some pathology of diverticulosis? List 3

A
  • Incidence; 30% in ——45+, 50% in 60+ and 66% in 85+
  • Typically painless
  • Most (60%) located in the left colon; descending colon
  • Diverticula of the right colon tend to bleed more often with 60-80% of bleeding being of arterial origin in the right colon
  • 20% of people with the disease will experience bleeding and 5% will experience massive haemorrhage
  • 2.5% of people over 60 are at risk of massive haemorrhage due to diverticular disease
  • A single diverticulum is generally the source of bleeding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is some pathology of angiodysplasia? List 3

A
  • Colonic angiodysplasia are acquired lesions
  • Typically multiple, painless, small and occur in the right colon
  • Degenerative lesions
  • Increasing incidence with age
  • Tend to cause slow and repeated episodes of capillary and venous bleeding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

There are 3 patterns of how a patient may present with LGIH. Explain one of these

A
  • Occult or obscure haemorrhage tends to be microscopic bleeds that may not be detectable by visual examination of the stools. Usually present with iron deficiency anaemia
  • Overt haemorrhage tends to be intermittent bleeding with visible evidence of blood in the stools (haemorrhoids). While the anorectum is the most common site, more proximal sources need to be eliminated as the source
  • Acute haemorrhage is continuous, gross bleeding from the rectum and patients may present as hemodynamically stable or unstable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the issue with LGIH?

A
  • Mortality rates are up to 30%
  • 85% spontaneously resolve
  • Critical to identify the 15% of high risk patients
  • Incidence increases with age
  • Aging population in Aus. Will see an emergence of acute LGIH as a major source of morbidity and health care cost
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

List the 4 steps to LGIH management

A
  • Characterise (the bleed); patient history and physical examination (upper or lower GIT)
  • Resuscitate; Intervention to stabilise physical condition (hypotension, BP, level of consciousness)
  • Differentiation and localisation: type of bleed (acute, occult, overt), bleeding rate (severity), detect and locate the bleeding site (colonoscopy, angiography and scintigraphy)
  • Treat; stop the bleeding and prevent recurrent bleeding (colonoscopy, angiography and surgery)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

List 3 of the 6 signs and symptoms of GIH

A
  • Haematemesis is bloody vomitus which can be bright red blood or matter of ‘coffee ground’ appearance
  • Melena results from degradation of blood in the GIT and is characterised by black, tarry stools with a foul odour
  • Haematochezia is generally associated with the passage of bright red or maroon blood from the rectum and may be in the form of bloody diarrhoea or blood mixed with a formed stool
  • Occult blood loss is generally only detected by laboratory examination of the stool.
  • Anaemia or other symptoms of blood loss.
  • Bleeding sites of the upper colon or distal small intestine generally result in dark blood in the stools while bleeding originating from the oesophagus, stomach or duodenum tend to produce melena.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the signs and symptoms of a sudden, massive haemorrhage?

A

weakness, dizziness or faintness, dyspnea, abdominal pain, diarrhoea, shock, tachycardia (greater than 110 beats per minute), hypotension (less than 100 mmHg systolic) or an orthostatic drop in blood pressure by greater than 16 mmHg, difficulty producing urine, pallor, oliguria or a change in mental status

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the diagnostic problem with GIH?

A
  • The origin of bleeding may be anywhere in the GIT
  • Bleeding is frequently intermittent
  • Evidence of active bleeding may not be obvious until after bleeding has ceased
  • Emergency surgery may be required for both a specific diagnosis and localisation of the bleeding site
  • Post therapy recurrence of bleeding is common
  • There is no consensus on appropriate patient management.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the imaging modalities utilised for GIH?

A
  • CT angiogram
  • Mesenteric Angiogram
  • Nuclear Scintigraphy (99m-Technetium labelled red blood cells)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

LGIH

- What are the benefits of a colonoscopy?

A
  • define anatomic cause
  • diagnosis of other pathology
  • doesn’t require active bleeding
  • therapeutic option
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

LGIH

- What are the limitations of a colonoscopy?

A
  • delay due to bowel preparation
    -poor visibility during active bleeding
  • expensive, invasive and higher risk
    expertise required
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

LGIH

- What is the role of a colonoscopy?

A
  • when bleeding has stopped

- when 99mTc RBC is negative

19
Q

LGIH

- What are the benefits of 99mTc RBC?

A
  • wide window of opportunity (hours) for imaging intermittent bleed
  • minimum detectable bleed rate of 0.1ml/min
  • cheap, safe and non invasive
    readily available
  • easily performed in acute illness
20
Q

LGIH

- What are the limitations of 99mTc RBC?

A
  • localisation, especially with retrograde or antegrade migration
  • minimum detectable bleed volume of 3.0-5.0ml
  • high background activity
21
Q

LGIH

- What is the role of 99mTc RBC?

A
  • intermittent bleeding
  • chronic bleeding
  • acute but not massive bleeding
  • minimise unnecessary angiograms
22
Q

LGIH

- What are the benefits of angiography?

A
  • therapeutic option
  • define anatomic cause
  • diagnosis of other pathology
  • accurate localisation when positive
23
Q

LGIH

- What are the limitations of angiography?

A
  • intermittent bleeding
  • narrow window of opportunity (minutes) for imaging intermittent bleeding
  • minimum detectable bleed rate of 1.0ml/min
  • expensive, invasive and higher risk
  • availability
  • expertise required
24
Q

LGIH

- What is the role of angiography?

A
  • acute, massive bleeding suspected to be occurring
  • following a positive 99mTc RBC
  • performed when active bleeding that precluded colonoscopy occurs after colonoscopy has failed
25
Q

What are the 3 main treatment options for LGIH?

A
  • Colonoscopy (first option)
  • Angiography
  • Surgery (mainstream option)
26
Q

LGIH

list 3 points of colonoscopic treatment

A
  • Colonoscopic coagulation generally provides temporary cessation of bleeding
  • Therapeutic options offered by colonoscopy include: mechanical devices, injection therapy, thermal methods, snares and polypectomy, laser therapy and argon plasma coagulation
  • Colonoscopic coagulation to be most effective in angiodysplasia but was associated with a 13% to 53% re-bleed rate
  • Despite the re-bleed rate, colonoscopic coagulation is preferred in angiodysplasia because angiography is ineffective due to the capillary and venous bleeding while surgery is associated with high mortality and morbidity
  • Colonoscopic coagulation is not usually appropriate in patients with diverticulosis because of the severity and location of the bleeding site
27
Q

LGIH

List 3 points of angiographic treatment

A
  • Angiography offers two main therapeutic options for the acute LGIH patient; vasopressin and embolization
  • Vasopressin is a pituitary hormone and following selective intra-arterial infusion into the mesenteric artery, causes vasoconstriction and contraction of the smooth muscle of the blood vessels and colon wall
  • Intra-arterial vasopressin infusion therapy is a simple yet long and labour intensive technique that leads to a 65% to 85% cessation rate in bleeding, however, re-bleeding occurs in 30% of patients
  • Transcatheter embolisation has emerged as a front line therapy
  • Percutaneous intervention is more immediate, more definitive but significantly more difficult with a catheter being required to be selectively introduced into the bleeding artery allowing introduction of a thrombogenic agent that occludes the vessel
  • Embolisation therapy aims to reduce arterial pressure while maintaining sufficient blood supply via collaterals to maintain viability
  • Embolisation has a high success rate (90% to 100%) and a re-bleed rate of virtually 0%
28
Q

LGIH

List 3 points of surgical treatment

A
  • Surgery is generally the option for the management of massive or recurrent LGIH
  • When the bleeding site is localised, the usefulness of segmental resection is well recognised, however, there are still many patients in whom ‘blind’ surgery is the only option
  • Up to 25% of acute LGIH patients will undergo surgery without presurgical localisation of the bleeding site
  • Emergency surgery is required in 10% to 25% of patients presenting with acute LGIH
  • More accurate localisation of the bleeding site has reduced mortality rate associated with surgery to 13% (from 28-47%)
  • Segmental resection, subtotal colectomy
29
Q

How does the biliary system work?

A
  • Hepatocytes take bilirubin out of the blood and drain it into the biliary tree which comes out through the common bile duct, sphincter body into the duodenum
  • Some will back fill via the cystic duct into the gallbladder –> bile
  • Bile is used to emulsify fats during digestion
30
Q

What is cholelithiasis?

A
  • Presence of 1 or more calculi (gallstones) in the gallbladder
  • Blockage of bile ducts can cause inflammation including bacterial infection
31
Q

What is acute cholecystitis?

A

Gallbladder inflammation developing over hours due to complete obstruction of the cystic duct

32
Q

What is chronic cholecystitis?

A

Long standing gallbladder inflammation without complete obstruction but usually associated with gallstones

33
Q

What is choledocholithiasis?

A

Presence of stones in the bile ducts

34
Q

What is cholangitis?

A

Bile duct inflammation and infection

35
Q

What are some signs and symptoms of cholecystitis?

A
  • RUQ pain
  • R shoulder pain
  • Tenderness
  • Nausea
  • Fever
36
Q

What is the role of ultrasound for imaging the biliary system?

A
  • Modality of choice for gallstones
  • Sensitivity and specificity both 95%; will show gallstones 95% of time, if it says they have gallstones, 95% of patients do
  • Can detect sludge
  • It is fast, real-time, non-invasive, and does not utilise ionizing radiation
  • High sensitivity for detection of cholelithiasis
  • Diagnosis based on visualisation of a mobile, hyperechoic, intraluminal mass with acoustic shadowing
  • High sensitivity for detection of acute cholecystitis
  • Diagnosis based on presence of cholelithiasis, gallbladder wall thickening, pericholecystic fluid
  • Limited by skill of operator, and patient’s body habitus.
37
Q

What are some features of acute cholecystitis on ultrasound?

A
  • Calculi in the gallbladder (GB), present in more than 90% of patients (calculi may be difficult to detect in the Hartmann pouch or cystic duct)
  • Anterior GB-wall thickness of more than 3 mm
  • Positive Murphy sign (pain on compression of the GB with the ultrasonographic probe)
  • Pericholecystic fluid in severe cases (indicative of actual or impending perforation)
  • Echo-poor halo in or around the GB wall or striated GB wall (indicative of oedema)
  • Non-visualisation of the GB in a truly fasting patient (strong evidence of GB disease)
38
Q

what is the role of x-ray in biliary system imaging?

A
  • This was used in the past, but has been widely replaced by the ultrasound
  • Can be used to visualise calcified stones, emphysematous cholecystitis (gas within the wall of the gallbladder), biliary fistula (gas within the biliary system), porcelain gallbladder.
39
Q

what is the role of oral cholecystography (OCG) in biliary system imaging?

A
  • Used to be the imaging modality of choice for detecting cholelithiasis. It is now used as an adjunct to ultrasound
  • Obtained when the patient has the symptoms of cholelithiasis, but a negative ultrasound
  • It is more useful than ultrasound for visualizing large stones, and also is useful for counting the number of stones present
  • Partially replaced by USG
40
Q

what is the role of CT in biliary system imaging?

A

The diagnosis of AC requires the presence of 2 major criteria or 1 major and 2 minor criteria. This classification is particularly helpful in the diagnosis of acalculous AC. Major criteria include the following:
-GB wall thickening of greater than 3 mm
-A halo surrounding the GB, resulting from oedema of the GB
-Extension of inflammation to the GB fossa
-Pericholecystic fluid in the absence of ascites
-GB mucosal sloughing
-Intramural GB gas
Minor criteria include:
-GB dilatation, with the transverse diameter being greater than 5 cm, and sludge in the GB.

41
Q

what is the role of Magnetic Resonance Cholangiopancreatography (MRCP) in biliary system imaging?

A
  • Becoming a more viable imaging technique, as MRI technology improves
  • However, CT and ultrasound are faster, easier, and more readily available, so they are used more frequently than MRCP
  • MRCP is emerging as a new tool for non-invasive evaluation of the pancreatic and biliary ductal systems
42
Q

what is the role of biliary scintigraphy in biliary system imaging?

A

Looking at the gallbladder and how the biliary tree functions give patient a fatty meal
Clinical indications:
-Acute cholecystitis
-Acalculous cholecystitis: acute and chronic
-Sphincter of Oddi dysfunction
-Biliary atresia
-Postoperative leaks
-Assess biliary reflux to duodenum and stomach after surgery
-Transplant assessment
-Focal nodular hyperplasia
-Hepatocellular carcinoma

43
Q

What are the treatment options for gallstones

A

Gallstones (uncomplicated):

  • Laparoscopic cholecystectomy
  • Stone dissolution using ursodeoxycholic acid
  • Non symptomatic rarely opt for surgery
  • Recurrence of pain means most symptomatic patient elect to have cholycystectomy
44
Q

What are the treatment options for acute cholecystitis?

A
  • Hydration
  • Antibiotics
  • Analgesics
  • Cholecystectomy
  • Percutaneous cholecystostomy for those with surgical risk and acalculous

MRS211 (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions