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JC WCS > Colorectal Surgery JC061: Fresh Blood In Stool: Lower GI Bleeding > Flashcards

Colorectal Surgery JC061: Fresh Blood In Stool: Lower GI Bleeding Flashcards

1
Q

Lower GI bleeding

A

Bleeding from gut ***distal to Suspensory ligament of Treitz (Duodeno-Jejunal flexure)
- Small bowel, Colon, Rectum, Anus
- trivial to life-threatening blood loss
- hard to differentiate —> haemorrhage from upper GI tract can present with features similar to lower GI bleeding

(Upper GI bleeding: Proximal to Suspensory ligament of Treitz
Small bowel bleeding: Distal to Major duodenal papilla, Proximal to IC valve)

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2
Q

Characteristics of Lower GI bleeding

A
  1. Acute / Chronic
    - Acute LGIB: bleeding of recent duration, may result in **instability of vital signs, anaemia, need for **transfusion (e.g. **Diverticulum bleeding, **Angiodysplasia)
    - Chronic LGIB: passage of blood over a period of several days, slow loss of blood (e.g. tumour)
  2. Overt / Occult
  3. Massive / Slow
  4. “Obscure GI bleeding”
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3
Q

Outlet bleeding

A

Bleeding from Anorectal sources:
- **Fresh blood
- **Separated from stool
- Variable amount, usually small
- ***Anorectal symptoms (e.g. pain in Anal fissure, prolapsed mass in Haemorrhoids)
- Usually no haemodynamic disturbance
- Assessed + Managed as outpatient

Common causes (記: 潰瘍, 發炎, 裂, 痔瘡, 腫瘤, 手術, 流血不止, Diverticulitis, Angiodysplasia):
1. **Haemorrhoids
2. Fissure-in-ano
3. Rectal ulcer (more common in elderly with chronic constipation)
4. **Colorectal neoplasm (esp. recent onset in elderly)
5. ***Proctocolitis
- IBD
- Radiation
- Infection

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4
Q

Acute Lower GI bleeding

A
  • Disease of elderly (∵ mostly due to **Diverticular disease, **Angiodysplasia)
  • Annual incidence requiring hospitalisation: 20-27 / 100,000
  • ↑ Incidence with advancing age
  • 200 fold ↑ in patients in 3rd decade to 9th decade
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5
Q

Management of Acute Lower GI Bleeding

A
  1. Resuscitation + Haemodynamic stabilisation
    - Venous access
    - **IV crystalloid solution —> expand IV volume
    - Cross match blood + **    Transfusion (if massive bleeding)
    - Monitor haemodynamic status
    - History, PE, Investigations should not delay resuscitation
  2. Localisation of bleeding site
  3. Therapeutic intervention
    - **Endoscopic
    - **    Angiographic
    - ***Surgery
    (Bleeding usually stop spontaneously in 75% patients)
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6
Q

Indications of Transfusion

A
  1. Profuse bleeding
  2. ***Persistent haemodynamic instability despite crystalloid resuscitation
  3. Symptomatic anaemia
  4. **AMI / Unstable angina with **low Hb (i.e. Haemodynamically unstable)
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7
Q

***History taking in Lower GI bleeding

A
  1. Severity
  2. Duration
  3. GI symptoms (abdominal pain / change in bowel habit)
  4. Anorectal symptoms
  5. Systemic symptoms
    - e.g. Coagulopathy
  6. History of previous bleeding episodes
  7. Previous investigations
  8. Significant comorbid conditions (heart / liver diseases)
  9. Medications (NSAID, anticoagulants, antiplatelets)
  10. Social history, Family history
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8
Q

P/E of Lower GI Bleeding

A
  1. Haemodynamic status
    - BP
    - Pulse
    - RR
    - **Urine output
    - **    CVP
  2. Abdominal examination (usually negative, seldom can feel abdominal mass)
  3. ***PR examination
    - characteristics of blood
    - anorectal conditions
  4. ***Proctoscopy
    - characteristics of blood
    - inflammatory changes in rectum
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9
Q

Investigations / Monitoring of Lower GI bleeding

A
  1. Haemodynamic status (TURBO-P)
    - BP
    - Pulse
    - RR
    - **Urine output
    - **    CVP
  2. Blood tests
    - Hb, Hct, MCV
    - Plt
    - LRFT
    - **Clotting profile
    - **    Type + Cross match for transfusion

Localisation of bleeding site
3. **Endoscopy
- Proctoscopy / Sigmoidoscopy —> exclude bleeding from anorectal pathology
- Upper endoscopy —> exclude UGIB (~10% proximal to ligament of Treitz in patients with haematochezia)
- Colonoscopy
- Enteroscopy
- Intraoperative endoscopy
- NG tube? —> bile stained aspiration: bleeding from UGIT excluded
4. **Angiography
5. Radionuclide scan (RBC, sulphur colloid)
6. Other imaging (CT, small bowel contrast)

(failure in localisation 8-12%)

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10
Q

Colonoscopy

A
  • Accurate tool to evaluate lower GI bleeding (75-90% diagnostic yield)
  • Early colonoscopy —> ↑ detection of bleeding source + shorter hospital stay
  • Low complication rate
  • Therapeutic procedure possible
    —> most bleeding from colonic lesions stop spontaneously
    —> therapeutic modalities (    Sclerotherapy (injection of sclerosants / vasoconstrictors), **Heat probe, Electrocoagulation, **Laser, **Haemoclips, **Argon beam coagulation)
    —> effective in Angiodysplasia, Diverticulitis, Proctocolitis
  • Bowel preparation:
    —> ↑ diagnostic yield without ↑ morbidity
    —> not feasible in unstable patients
    —> balance between accuracy of colonoscopy / tolerance of patients to bowel prep (bleeding might have stopped before bowel prep done)
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11
Q

CT angiography

A
  • Similar accuracy to Scintigraphy
  • Quicker + More accurate
  • Can be performed prior to Conventional Angiography
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12
Q

Conventional Angiography

A
  • Confirm bleeding + Locate bleeding site
  • Selective catheterisation of SMA, IMA, Celiac artery by ***Seldinger technique
  • Bleeding 1-1.5 ml/min can be detected
  • Positive test: ***Extravasation of contrast into lumen (X presence of lesion)
  • 27-67% diagnostic yield
  • Complications:
    —> ***Contrast allergy
    —> Renal failure
    —> Bleeding from puncture site
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13
Q

Therapeutic angiography

A
  1. ***Embolisation
    - risk of bowel ischaemia, infarction
  2. ***Injection of vasopressin (vasoconstrictor)
    - cardiac SE
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14
Q

Radionuclide scan

A
  • **Tc-99 labelled Sulphur colloid / **Tagged RBC
  • Labelled RBC not cleared rapidly + not taken up by liver / spleen
  • ***High sensitivity (80-98%: detects bleeding as slow as 0.1 ml/min)
  • No therapeutic value
  • Less specific
    —> **less able to locate bleeding site (vs Angiography)
    —> used as **    screening tool to confirm bleeding prior to Angiography for non-life-threatening bleeding
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15
Q

Surgery

A
  • Required in ~15-20% of patients with Acute LGIB
  • ***Last resort, usually delayed (∵ bleeding usually not profuse, haemodynamic less affected)
  • Indications:
    —> **Haemodynamic instability
    —> **    Transfusion requirement (>=6 units of blood)
    —> ***Persistent bleeding
    —> Rebleeding within 1 week

With localisation:
- ***Segment resection

Without localisation:
- **Subtotal colectomy if bleeding from colon
- **Intraoperative Colonoscopy / Enteroscopy for localisation

Outcome:
- Segmental resection with localisation:
—> rebleeding: 0-15%
—> mortality: 0-13%

  • Blind segmental resection:
    —> rebleeding: up to 75%
  • Subtotal colectomy:
    —> mortality: 0-40%
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16
Q

***Common causes of Lower GI bleeding

A

記: Diverticulosis, Angiodysplasia, Colitis, Tumour, Anorectal, Small bowel

  1. ***Diverticular disease
  2. ***Ischaemic colitis (∵ degenerative vessels)
  3. ***Angiodysplasia (∵ vascular ectasia)
  4. Colitis
    - IBD
    - radiation (e.g. treatment for gynaecological tumour, prostate cancer)
    - infective
  5. ***Neoplasm
  6. Post-polypectomy
  7. ***Anorectal sources
    - haemorrhoids
    - rectal ulcers
    - rectal varices
    - fissures
  8. Small bowel sources
    - Meckel’s diverticulitis
    - Vascular lesions (    Angiodysplasia, Haemangioma)
    - Small bowel tumours
    - Small bowel ulcers (    NSAID induced)
    - ***Crohn’s disease
    - Aortoenteric fistula
  9. Massive bleeding from UGIT
17
Q

Diverticular disease

A
  • Western: Sigmoid colon
  • Asia: ***Ascending colon

Treatment:
- Injection with adrenaline

18
Q

Angiodysplasia

A
  • ***Ectasia of vessels lying in Submucosa
  • Acquired condition associated with degeneration (2/3 >=70yo)
  • May be associated with Vascular malformations in other GI tract (**Osler-Weber-Rendu disease (HHT)) and **Aortic stenosis

Features:
- More commonly in **Descending colon (but can occur throughout whole colon)
- Bleeding less severe than Diverticular haemorrhage (but tends to be **intermittent i.e. higher recurrence rate)
- Bleeding stops in 85-90%
- Rebleeding 25-85%

Treatment:
- ***Not necessary for non-bleeding angiodysplasia
- Endoscopic
- Surgery

19
Q

Colitis

A
  1. IBD
    - **Crohn’s disease (sometimes significant bleeding)
    - **    Ulcerative colitis (rectum + diarrhoea)
  2. Infective colitis
  3. ***Radiation colitis (more common now)
    - treatment for gynaecological / prostate cancer
  4. ***Ischaemic colitis
    - ∵ atherosclerosis
  5. Idiopathic ulcers
20
Q

IBD

A
  • ***Bloody diarrhoea
  • Not life-threatening

UC:
- Bloody diarrhoea
- Small amount
- 6-10% UC with LGIB enough to necessitate emergency surgery
- **High chance of rebleeding
—> **Surgery recommended
—> Total colectomy in emergency

Crohn’s disease:
- Life-threatening LGIB uncommon
- Usually due to colitis
- **Total colectomy recommended
—> Anastomosis: depend on extent of rectal involvement
- **Segmental small bowel resection (preserve as much as possible) for bleeding from small bowel (localisation of lesion)

21
Q

Radiation proctocolitis

A

Features:
1. **Damage of rectal mucosa (∵ long term SE from radiation treatment)
2. Formation of Vascular **telengiectasis
3. Chronic rectal bleeding (1-5% necessitate hospitalisation + transfusion regularly)

Treatment:
1. No cure (∵ damage done, cannot be reversed)

  1. **Endoscopic treatment (multiple sessions)
    - **    Infrared coagulation
    - **Argon beam coagulation
    - **    Laser
  2. ***Formalin: Local application of 4% formalin
  3. ***Surgery (for uncontrolled bleeding)
    - Diversion colostomy
    - Proctectomy (high mortality / morbidity)
22
Q

Anorectal sources

A
  • ~10% LGIB

Causes:
1. Haemorrhoids (∵ faecal impaction —> faecal evacuation)
2. Fissure-in-ano
3. Anal / Rectal ulcer
4. Rectal varices
- associated with portal hypertension
- severe bleeding
- local therapy: ***injection sclerotherapy
- surgery: shunting (for uncontrolled bleeding)

Investigations:
- PR exam
- Proctoscopy

23
Q

Obscure GI bleeding

A

Bleeding of unknown origin that persists / recur after a negative initial endoscopy (Colonoscopy / Upper endoscopy)
- ***usually in Small bowel

Treatment:
- Repeat Colonoscopy / Upper endoscopy
—> identified 35% of bleeding lesions in Small bowel

24
Q

***Bleeding from small bowel

A
  • 5% LGIB

Causes (記: Diverticulosis, Angiodysplasia, Colitis, Tumour, Drug):
1. **Angiodysplasia
2. Jejunoileal diverticula
3. **Meckel’s diverticulum (Ectopic gastric / pancreatic mucosa)
4. **Neoplasm
- GIST (grow towards mucosa causing ulcer —> bleeding)
- Neuroendocrine tumour
- Adenocarcinoma (rare)
5. **Crohn’s enteritis
6. ***Drug related ulcers
7. Infection (TB)

(vs Upper GI bleeding (記: 潰瘍, 發炎, 靜脈曲張, 嘔, 腫瘤))

25
Q

Diagnosis of Small bowel bleeding

A
  1. ***Angiography
    - difficult to interpret (SMA? IMA? Celiac artery?)
  2. ***RBC scan
    - non-specific
  3. Small bowel enema
  4. ***CT Enteroclysis
    - low yield
    - cannot detect vascular lesions
  5. **Enteroscopy
    - Push enteroscopy
    - **    Single balloon enteroscopy
    - **Double balloon enteroscopy
    - **    Intraoperative
26
Q

Push enteroscopy

A
  • Upper endoscopy beyond ***DJ flexure
  • Paediatric colonscope
  • Long endoscope with ***overtube (therapeutic tools to stop bleeding)
  • Length of Jejunum examined varies
  • Procedures well tolerated with few complications
  • Channel for therapeutic measures
  • 30% diagnostic yield
27
Q

Capsule enteroscopy

A
  • Diagnostic capsule that take colour video images
  • ***Need bowel preparation
  • Signal of its location transmitted + detected by sensor (carried by patient, can be ***ambulatory)
  • No additional diagnosis made by push enteroscopy
28
Q

Double balloon enteroscopy

A
  • Long
  • ***Specialised balloons + overtube
    —> anchor overtube + advance endoscope (蚯蚓咁郁)
    —> to advance scope into more distal part of small bowel
  • Tip of scope can be smoothly inserted to reach area of diagnosis
  • Passes from mouth / anus to completely examine small bowel
  • ***Biopsy / Therapeutic procedures can be performed
29
Q

Intraoperative endoscopy

A
  • In situations where prior localisation cannot be made
  • Allows ***complete examination of small bowel
  • Higher diagnostic yield

Colonoscopy:
- Foley catheter inserted through appendicotomy / enterotomy
- Bowel preparation by on table antegrade irrigation
- Effluent from anus

Route:
- Trans-anal
- Per-oral
- Through enterotomy
- Laparoscopic assisted

30
Q

Summary

A
  • Successful management of LGIB requires aggressive resuscitation + localisation of bleeding site
  • Surgery indicated in massive + continuous bleeding
    —> require good localisation of bleeding site
  • Bleeding from small bowel is difficult to localise

JC WCS (134 decks)

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