GI Bleeding Flashcards
GI bleeding 2 types
- Overt (visible bleeding)
- Occult (no exteriorization of blood, but person is slowly becoming anemic)
Epidemiology: 4 most common types/causes of GI bleeding
- Upper GI bleeding (60.6)
- Lower GI bleeding (35.7)
- Peptic ulcer bleeding (32.1)
- Colonic diverticular bleeding (23.9)
3 types of overt GI bleeding
- Upper (esophagus, stomach, upper duodenum)
- Obscure/Middle (small intestine)
- Lower (large intestine, rectum)
Know how to define these in terms of GI regions!
Upper GI bleeding - Symptoms (3)
- Hematemesis (vomiting of blood or coffee-ground material)
- Melena (black, tarry stool)
- Hypovolemic shock (+/-)
What percentage of patients who present with hematochezia (passage or RBCs or clots per rectum) have an upper GI source of bleeding?
15-20%
3 main causes of severe upper GI bleeding
- gastric or duodenal ulcer
- gastric or esophageal varices (rupture)
- erosive esophagitis (due to reflux, drugs, toxins)
Upper GI bleeding: Initial Management (4 steps)
- ABCs (IV, intubation, INR correction)
- Type and cross-match (figure out what blood type the patient has and make sure transfusion blood is ready if needed)
- Fluid resuscitation
- Risk stratification (clinical or endoscopic)
How can the nitrogen and creatinine level help us diagnose upper GI bleeding
In upper GI bleeding, the blood urea nitrogen level typically increases to a greater extent than the creatinine level.
Patients with upper GI bleeding should undergo … within 12-24 hours.
endoscopic evaluation
Why is endoscopic evaluation so important for patients with upper GI bleeding
It identifies the site of bleeding with a sensitivity of 92% and a specificity near 100% while also providing hemostasis, if needed.
What is the goal of endoscopic therapy for UGIB? (2)
To stop acute bleeding and reduce the risk of recurrent bleeding.
Endoscopic therapy (UGIB) is reserved for…
lesions that have a high risk stigmata
What are some of the available endoscopic treatments (4)
Injection
Thermal coagulation
Mechanical compression (clips)
Hemostatic powders
Briefly understand how these work
Briefly describe the following endoscopic treatments:
Injection
Thermal coagulation
Mechanical compression
Hemostatic powders
Injection: Epinephrine is injected to the site of injury to induce vasoconstriction
Thermal coagulation: A probe applies heat to coagulate the bleeding vessel
Mechanical compression: Hemostatic clips are placed on the bleeding vessel to stop the bleeding.
Hemostatic powders: Are sprayed on the site of bleeding to promote clot formation
Describe the medical therapy for (non-variceal) UGIB (i.e. medications)
Proton Pump Inhibitors:
Result in profound acid suppression that promotes platelet aggregation and clot formation
Why are PPIs such a good therapy for UGIB?
They reduce re-bleeding and surgery rates; in patients with high-risk stigmata post endoscopic therapy reduce mortality.
For patients with high-risk stigmata post endoscopic therapy - What is the PPI dose?
High-dose IV PPI over 72 hours (reduces mortality)
UGIB prognosis depends on…
the cause of bleeding
Compare the chances of re-bleeding if the UGIB cause is non-variceal vs variceal
Non-variceal: 9%
Variceal: 60%
Compare the mortality risk if the UGIB cause is non-variceal vs variceal
Non-variceal: 2%
Variceal: 33%
Explain variceal bleeding in the esophagus (UGIB)
Variceal bleeding happens because of high pressure in the portal vein (portal hypertension), usually due to liver cirrhosis. This forces blood to reroute (shunt) through small veins in the lower esophagus, causing them to swell and form varices. These swollen veins have thin walls and can easily break, leading to severe bleeding into the esophagus.
How is variceal UGIB treated?
Combination of pharmacotherapy and endoscopy.
Pharmacotherapy:
* octreotide
* somatostatin
* antibiotics
Endoscopy:
* band ligation, sclerotherapy
Also if needed: radiological therapy (prosthetic shunting)
What may suggest lower GI bleeding on history? (3)
- History of diverticulosis
- Abdominal cramping followed by bloody diarrhea
- Recent polypectomy.
Lower GI bleeding: Initial Management
- Resuscitation (same as UGIB)
- Endoscopic evaluation
- Flexible sigmoidoscopy/anoscopy
- Colonoscopy
What is the purpose of a colonoscopy in LGIB management? (2)
Allows for diagnosis
May help with hemostasis of amenable lesions
In what case is colonoscopy not useful (LGI)
Acute setting (severe bleeding - you won’t even see anything)
Most common causes of lower Gi bleeding (5)
- Diverticulosis
- Internal hemorrhoids
- Ischemic colitis
- Rectal ulcers
- Colonic vascular lesions
Briefly define diverticulosis
Diverticulitis occurs when small bulging pockets form on the inner wall of the colon. They may rupture and bleed.
LGIB: Therapy
Hemodynamically unstable
Hemodynamically stable
Severe/persistent bleeding
If hemodynamically unstable:
1. Stabilize the patient (resuscitation, ABCs)
2. Consider upper endoscopy once stabilized (to rule out upper GI source of bleeding)
Hemodynamically stable:
Elective colonoscopy (urgent colonoscopy does not improve outcomes)
Severe/Persistent bleeding:
Perform radiologically guided percutaneous embolization
What is the risk of angiographic embolization or infusion of vasoconstrictors when treating LGIB?
10% risk of causing local ischemia
(but success rate is 80%)
Is surgical management of LGIB often required?
No, because most LGIB is self-limited or easily managed with medical or endoscopic therapy (LGIB is less dangerous than UGIB).
Surgical treatment of LGIB is reserved for… (2)
- Patients with malignat lesions
- Patients with recurrent or persistent ischemic colitis or diverticulosis
What is the prognosis for LGIB? What does it depend on?
Overall mortality rate is low (2-4%).
The outcome depends on the cause of bleeding (but is favourable in most cases).
Where is the source of bleeding in patients with obscure (middle) GI bleeding?
The small intestine or any region that is beyond the reach of an upper endoscope or colonoscope.
We consider obscure GI bleeding to be present if…
bleeding is persistent and recurrent despite a negative initial GI evaluation (including upper endoscopy and colonoscopy).
Since the small intestine cannot be accessed by endoscopy nor colonoscopy, how can we examine for obscure bleeding?
Videocapsule endoscopy (enteroscopy): a non-invasive procedure that uses a small, pill-sized camera that the patient swallows
Most common cause of small intestinal bleeding (obscure GIB)
Vascular lesions (angiectasias)
Abnormal, dilated blood vessels in the GI that can cause chronic or intermittent bleeding
Other than vascular lesions, 2 other causes of small intestinal bleeding
Ulcers
Tumours
Name 2 types of lesions that cause obscure GI bleeding and are within reach of standard endoscopes but are not recognized as the bleeding site.
Cameron’s ulcers
Internal hemorrhoids
Name an intermittently bleeding lesion considered a source of obscure Gi bleeding
Dieulafoy’s lesion
What is another name for enteroscopy?
videocapsule endoscopy
What is an important consequence of both overt or occult blood loss?
Iron deficiency
Is iron deficiency frequently caused by GI bleeding?
No, a lot of the time it is caused by…
* iron deficiency in diet
* iron malabsorption
* chronic red blood cell destruction (hemolysis)
