This document discusses lower gastrointestinal (GI) bleeding, including: - Causes of lower GI bleeding in adults include diverticulosis, angiodysplasia, and colorectal cancers and polyps. Risk factors include low fiber diet and medications like NSAIDs. - Evaluation involves history, physical exam, labs, and endoscopic procedures like colonoscopy to identify the bleeding source and provide treatment. - Colonoscopy is the gold standard for diagnosis and treatment but must be performed carefully in unstable patients. Angiography and nuclear scans can help localize bleeding in severe cases.

1. Lower GI Bleeding
Dr. Kiran Pandey
MS General Surgery Resident (NAMS)
MS General Surgery Resident

2. Lower GI bleeding is defined as abnormal
hemorrhage into the lumen of the bowel from
a source distal to the ligament of Treitz

3. Epidemiology
 Overall mortality <5%.
[Frequency and severity of UGIB >LGIB]
 LGIB is more common in women > men.
 Incidence and prevalence related to specific etiologies
 More than 80% of lower GI bleeds will stop
spontaneously, and overall mortality has been noted to
be 2% to 4%.

4. • Lower GI bleeds: 20% to 30% of all patients
presenting with major GI bleeding.
• The incidence is higher in older patients and
multiple medications.
• Approximately, 80% to 85% originate distal to the
ileocaecal valve, with only 0.7% to 9% originating
from the small intestine.
• The remaining cases usually begin in the upper GI
tract. Present with brisk bleeding, melena, or
bright red blood per rectum.

5. Categorization based on severity
Massive
Moderate
Mild

6. https://www.ncbi.nlm.nih.gov/books/n/statpearls/article-22103

7. Risk factors
 Low fiber diet
 Obesity, Physical Inactivity
 Radiation
 NSAID or Aspirin usage
 Advancing age
 Co morbidities

8. Causes in adults
Diverticulosis (30 - 50%)
Angiodysplasia (20 - 30%)
(or AVM, or Vascular Ectasias)
Neoplastic (10- 15%)
Polyps
Cancer

9. Causes in adults
Inflammatory (15 - 20%)
Radiation - Intestinal damage due to fibrosis and
ischemia.
IBD
Ulcerative colitis
Crohn’s Disease
Infectious (E. Coli 0157:H7, C. Difficile, C. Jejuni )
Ischemic (Hypoperfusion and Vasoconstriction)
Hypotension, Heart Failure, Arrhythmia
Vasculitis

10.  Others (5 – 10%)
Post-polypectomy bleeding
Aortoenteric fistula
Coagulation deficiency
 Hemorrhoids
(< 50 y.o. most common) (5 – 10%)
 Unknown (10 – 15%)
Causes in adults

11. Causes in children
 Anal Fissure
 Infectious Colitis
 IBD
Crohn’s Disease
Ulcerative Colitis
 Polyps
 Intussusception
 Meckel’s Diverticulum (embryonic diverticulum)
 Pseudomembransous Colitis

13. History
chronicity of bleeding and medication
use .
 anti coagulants such as warfarin.
 low molecular weight heparin.
 inhibitors of platelet aggregation such
as NSAID
 clopidrogel this can
 associated with mesentric
ischemia

14. History
Use of digitalis
can associated with mesenteric ischemia
Comorbid medical conditions like cardiac
conditions.
Family history of colorectal cancer
Coagulopathy

15. Signs and Symptoms
 Hematochezia (most often painless)
 Anemia
 Occult blood in stool
 Rarely melena (UGIB most common)
 Normal Bowel Sounds, Normal Renal
Function (BUN/Cr)
 Nasogastric aspirate usually clear

16.  Massive upper gastrointestinal bleed can
present with hematochezia.
 An NG aspirate that contains bile and no
blood effectively rules out upper tract
bleeding in most patients.
 Majority of cases bleeding regresses
spontaneosly

17.  Outcome depends on risk stratification
 Predictors of poor outcome in lower GI bleed
 Hemodynamic instability
 Ongoing hematochezia
 Presence of comorbid illness

18. CONDITIONS WITH RECTAL BLEEDING BUT NO PAIN:
 Blood mixed with stool :colon carcinoma
 Blood streak on stool:rectal carcinoma
 Blood after defaecation: haemorrhoids
 Blood and mucus: colitis
 Blood alone diverticular disease
 Melaena:peptic ulcer

19.  PAIN AND BLEEDING:
Fissures
 PAIN, LUMP AND BLEEDING:
Prolapsed haemorrhoids
Carcinoma of the anal canal
Prolapsed rectal polyp or
carcinoma
Prolapsed rectum

20. Manangement
 Includes
a) Identification of site of bleeding
b) Stopping the bleeding and treating the cause
c) Digital rectal examination should be done to
exclude anorectal pathology as well as
confirm the patient’s description of stool
color.

21. Investigations
 CBC - Anemia, Infection, Thrombocytopenia, Protein
Levels, Iron, Crossmatch
 Coagulation
 Hemoccult and Stool cultures
 ECG

22. Endoscopic investigations
 Proctoscopy
 Sigmoidoscopy
 Colonoscopy
 Video Capsule Endoscopy
 Double balloon endoscopy
 Intraoperative Endoscopy

23. Radiological investigations
 Abdominal X rays
 Angiography
 Radionuclide scintigraphy
• Technetium Sulfur Colloid
• 99mTc pertechnate-labeled RBC
 Multidetector row CT (MDCT)
Barium studies have no role in lower GI
bleeding

25. Colonoscopy
 Usually done after stabilizing the patient
 Provide both diagnosis and hemostasis
 Better than Sigmoidoscopy
 The diagnostic yield of urgent colonoscopy in
between 75-97% , depending on the definition
of the bleeding source, patient selection criteria,
and timing of colonoscopy

26.  Bowel preparation
 Recent studies have suggested that performiang colonoscopy
shortly after presentation is advantageous

27. Criteria for identifying site of bleeding oncolonoscopy
 Active colonic bleeding
 Adherent clot
 Fresh blood localized to a colonic segment
 Ulceration of diverticulum with fresh blood in
adjoining area
 Absence of fresh bleed in terminal ileum with
fresh blood in the colon

29. Screening of colorectal cancer and adenomatous
polyps is Asymptomatic men and women ≥ 50 years
of age
Screening for colorectal cancer

30. Low-risk individuals:
Complete colonoscopy (gold standard):
Repeat every 10 years if no polyps or Carcinoma
Annual fecal occult blood test ( FOBT):
Sigmoidoscopy every 5 years and FOBT every 3 y
Annual fecal immunochemical testing (FIT)
CT colonography every 5 years

31. Histology of removed polyp Recommended interval until next
control colonoscopy
Hyperplastic Polyp < 10 mm in size in
the rectum or sigmoid
10 years
•Low risk ademoma: 1–2 tubular polyps < 10
mm in size and without
intraepithelial Neoplasia (IEN)
5–10 years
•High risk adenoma
• 3–10 tubular polyps
• 1 polyp ≥ 10 mm
• 1 villous or tubulovillous polyp
• 1 tubular polyp with high-
grade dysplasia
3 years
•More than 10 adenoma < 3 years; depends on the case (i.e., family
history)
Surveillance following Polypectomy

32. High-risk individuals
Complete colonoscopy 10 years earlier than the
index patient's age at diagnosis or no later than 40
years of age

33. Lynch syndrome and FAP syndrome
Colonoscopy:
every 1–2 years, starting at 20–25 years of age, or
2–5 years before the earliest recorded case in family
whichever comes first
Annual upper endoscopy with biopsy of the gastric
antrum starting at 30–35 years of age
Annual physical exam and urinylasis

34. Video Capsule Endoscopy
 Capsule endoscopy uses a small capsule with a
video camera that is swallowed and acquires
video images as it passes through the GI tract.
 This modality permits visualization of the entire
GI tract, but offers no interventional capability.
 It is also very time consuming

36.  Visualizes entire gastrointestinal tract
in real time
 The two balloons inflate and deflate
intermittently creating a peristaltic
movement so that the scope can
move forward
Double balloon endoscopy

37. Intraoperative Endoscopy
 Intraoperative enteroscopy is reserved for patients
who have transfusion-dependent obscure-overt
bleeding in whom an exhaustive search has failed
to identify a bleeding source.
 This typically uses a pediatric colonoscope
introduced through an enterotomy in the small
bowel made by the surgeon.

38. Abdominal X rays
 Perforation
 Obstruction
 “Thumb-printing” = Ischemic/Infectious
Colitis
 Megacolon

39. Angiograph
 Both diagnostic and therapeutic
 Requires a bleeding rate of at least 0.5 to 1.0 ml/min
 Done in hemodynamically unstable patients
 Reserved for massive bleeding

40.  Vasopressin was the first therapeutic modality
 Major complications occurred in 10% to 20% of
patients and included arrhythmias, pulmonary
edema, hypertension and ischemia
 Re bleeding occurred in up to 50% of patients
 Earlier embolization was associated with
infraction
 Technologic advances in coaxial microcatheters
and embolic materials have enabled the
embolization of specific distal arterial branches
with increased success and fewer complications

41. Radionuclide scintigraphy
 Non-invasive
 Done as screening before angiography
 More sensitive
 Detects bleeding as low as 0.1 ml/min
 Major disadvantage false localisation
 Two methods are used
Technetium Sulfur Colloid
99mTc pertechnate-labeled RBC

42. Tc-99m Red Blood Cells
 Tc-99m RBCs remain in the vascular
compartment
 In vitro or modified in vivo labeling of RBC is
done
 Allows continuous monitoring of the whole
gastrointestinal tract for a long period
 False-positive readings due to misinterpretation
of intravascular activity and the possibility of
free pertechnetate accumulation
 sensitivity and specificity of this method are
very high

43. Tc-99m sulfur colloid
 Rapid blood clearance of this tracer from
circulation allows for increased detection at
very low bleeding rates (0.05 to 0.1 ml/min)
 Detects bleeding only up to 15 minutes after
intravenous injection

45. Multidetector Row CT (MDCT)
 Show contrast extravasation into any portion of the
gastrointestinal tract
 Detects bleeding rates as low as 0.3 to 0.5 ml per minute
 The average yield of MDCT for lower GI bleed Is 60%, with yields
ranging from 25% to 95%.
 Lack of therapeutic capability is a major limitation
 Useful in guiding further:angioembolisation

47. Advantages and disadvantages of common diagnostic procedures used in the evaluation of lower
gastrointestinal bleeding
Procedure Advantages Disadvantages
Colonoscopy
-
• Bowel preparation required
•Can be difficult to orchestrate without on
call endoscopy facilities or staff
• Invasive
Angiography
• Therapeutic possibilities
•Diagnostic for all sources of
bleeding
•Needed to confirm diagnosis in
most patients regardless of initial
testing
• Efficient/cost -effective
• No bowel preparation needed
• Therapeutic possibilities
• May be superior for patients with
severe bleeding
Radionuclide
scintigraphy
• Noninvasive
•Requires active bleeding at the time of the
exam
• Less sensitive to venous bleeding
• Diagnosis must be confirmed with
endoscopy/surgery
• Serious complications are possible
• Variable accuracy (false positives)
• Sensitive to low rates of bleeding
• No bowel preparation
• Easily repeated if bleeding recurs
Flexible
sigmoidoscopy
• Diagnostic and therapeutic
• Not therapeutic
• May delay therapeutic intervention
• Diagnosis must be confirmed with
endoscopy/surgery
• Visualizes only the left colon
• Minimal bowel preparation • Colonoscopy or other test usually
necessary to rule out right- sidedlesions
• Easy to perform

49. Conclusions:
Post-interventional LGIB was effectively addressed by LE. For other causes of LGIB, CTA was
efficient, and more available than colonoscopy. Treatment was conservative for most patients.
In case of active bleeding, CTA could localize the bleeding source and predict the need for
surgery.

50. References
• Bailey’s and Love Short Practice of Surgery, 26th Edition
• Hammilton Bailey’s Demonstration of physical sign in clinical Surgery 19th Edition
• Clerc et al. World Journal of Emergency Surgery (2017) 12:1 DOI 10.1186/s13017-
016-0112-3
• Edelman, D.A., Sugawa, C. Lower gastrointestinal bleeding: a review. Surg
Endosc 21, 514–520 (2007). https://doi.org/10.1007/s00464-006-9191-7
• https://www.ncbi.nlm.nih.gov/books/n/statpearls/article-22103
• Lower Gastrointestinal Bleeding, Don C. Rockey
DOI: https://doi.org/10.1053/j.gastro.2005.11.042
• https://www.cancer.org/cancer/colon-rectal-cancer/detection-diagnosis-
staging/screening-tests-
• https://www.amboss.com/us/knowledge/Colorectal_cancerused.html
• https://www.amboss.com/us/knowledge/Lynch_syndrome#xid=fS0k_2&anker=Z2
23291f8ddc1791ddb38550c25b8a05c