LOWER GI BLEEDNG

CLINICAL PRESENTATION A 68 yrs old presents to the ER with BRBPR. He has several

episodes, beginning on the evening before presentation. He describes the bleeding as profuse and filling the toilet, he felt

light headed and almost passed out while sitting on the toilet. PMHx: htn Meds: amlodipine P.Ex: B.P. =86/42mm hg, pulse = 134/min,

pt. is orthostatic. Abdominal examination reveals slight

abdominal distention with hyperactive bowel sounds. Rectal exam shows gross blood

Wbc-10 Hct-28 % Plt-180 Lytes – wnl Coagulation profile wnl LFTs wnl

Estimation of blood lossEstimated Fluid and Blood Losses in Shock

Class 1 Class 2 Class 3 Class 4

Blood Loss, mL

Up to 750 750-1500 1500-2000 >2000

Blood Loss,% blood volume Up to 15% 15-30% 30-40% >40%

Pulse Rate, bpm <100 >100 >120 >140

Blood Pressure

Normal Normal Decreased Decreased

Respiratory Rate

Normal or Increased

Decreased Decreased Decreased

Urine Output, mL/ h

14-20 20-30 30-40 >35

CNS/ Mental Status

Slightly anxious

Mildly anxious

Anxious, confused

Confused, lethargic

Fluid Replacement, 3-for-1 rule

Crystalloid Crystalloid Crystalloid and blood

Crystalloid and blood

Initial steps in the management of upper gastrointestinal bleeding

Airway protection

Airway monitoring

Endotracheal intubation (if indicated)

Hemodynamic stabilization

Large bore intravenous access

Intravenous fluids

Red cell transfusion (for symptomatic anemia)

Fresh-frozen plasma, platelets (if indicated)

Consider erythropoeitin

Nasogastric oral administration

Large bore orogastric tube/lavage

Clinical and laboratory monitoring

Serial vital signs

Serial hemograms, coagulation profiles, and chemistries (as clinically indicated)

Electrocardiographic monitoring

Hemodynamic monitoring (if indicated in high-risk patients)

Endoscopic examination and therapy

RESUSCITATION High-risk patients (eg, those who are elderly or who have severe

co morbid illnesses such as coronary disease or cirrhosis) should receive packed red blood cell transfusions to maintain the hematocrit above 30 percent.

Patients who are elderly or have known cardiovascular disease are at increased risk for a myocardial infarction and should thus be monitored appropriately; consideration should be given to ruling out a myocardial infarction.

Young and otherwise healthy patients should be transfused to maintain their hematocrit above 20 percent.

Patients with active bleeding and a coagulopathy (prolonged prothrombin time with INR >1.5) or low platelet count (<50,000/microL) should also be transfused with fresh frozen plasma and platelets, respectively.

Lower GI bleeding

Next step

Risk stratificationInitial Emergency Department Risk Stratification for Patients with Gastrointestinal Bleeding

Low Risk Moderate Risk High Risk

Age <60 Age >60

Initial SBP ≥100 mm Hg

Initial SBP <100 mm Hg

Persistent SBP <100 mm Hg

Normal vitals for 1 hr Mild ongoing tachycardia for 1 hr

Persistent moderate/severe tachycardia

No transfusion requirement

Transfusions required ≤4 U

Transfusion required >4 U

No active major comorbid diseases

Stable major comorbid diseases

Unstable major comorbid diseases

No liver disease Mild liver disease—PT normal or near-normal

Decompensated liver disease—i.e., coagulopathy, ascites, encephalopathy

No moderate-risk or high-risk clinical features

No high-risk clinical features

Risk stratification Strate and colleagues retrospectively collected data on 24

clinical variables available in the first 4 hours of evaluation in 252 consecutive patients. Seven independent predictors of severity in acute LGIB

hypotension tachycardia, syncope, nontender abdominal exam, bleeding within 4 hours of presentation, aspirin use, and more than two comorbid diseases

Risk stratification

Based on these factors, patients could be stratified into three risk groups:

Patients with more than three risk factors had an 84% risk of severe bleeding,

One to three risk factors a 43% risk, and No risk factors a 9% risk.

Risk stratification

In another study clinical predictors in the first hour of evaluation in patients with severe LGIB included

initial hematocrit of no more than 35%, presence of abnormal vital signs 1 hour

after initial medical evaluation, and gross blood on initial rectal examination.

Next step

localization An upper gastrointestinal source of bleeding is detected in 10% to

15% of patients presenting with severe hematochezia . Patients with hemodynamic compromise and hematochezia should

have a nasogastric tube placed. If bile is present, an upper source is unlikely.

If the aspirate is nondiagnostic (no blood or bile), or if there is a strong suspicion of an upper bleeding source (i.e., history of previous peptic ulcer disease or frequent NSAID use), then an upper endoscopy should be performed before examining the colon .

An upper endoscopy should be performed if no source of bleeding is identified during colonoscopy.

LOCALIZATION The duration, frequency, and color of blood passed per rectum

may help discern the severity and location of bleeding. Characteristically, melena or black, tarry stool, indicates bleeding

from an upper gastrointestinal or small bowel source, Maroon color suggests rt. Sided lesion whereas bright red blood per rectum signifies bleeding from the

left colon or rectum. However, patient and physician reports of stool color are often inaccurate and inconsistent

In addition, even with objectively defined bright red bleeding, significant proximal lesions can be found on colonoscopy

LOCALIZATION past medical history may also help to elucidate a specific bleeding source. antecedent constipation or diarrhea (hemorrhoids, colitis), the presence of diverticulosis (diverticular bleeding), receipt of radiation therapy (radiation enteritis), recent polypectomy (postpolypectomy bleeding), and vascular disease/hypotension (ischemic colitis). A family history of colon cancer increases the likelihood of a colorectal

neoplasm and generally calls for a complete colonic examination in patients with hematochezia.

Nonetheless, even after a detailed history, physicians cannot reliably predict which patients with hematochezia will have significant pathology and a history of bleeding from one source does not eliminate the possibility of bleeding from a different source.

LOCALIZATION Multiple factors make the identification of a precise

bleeding source in LGIB challenging. The diversity of potential sources, The length of bowel involved, The need for colon cleansing, and The intermittent nature of bleeding. In up to 40% of patients with LGIB, more than one

potential bleeding source will be noted and Stigmata of recent bleeding in LGIB are infrequently

identified As a result, no definitive source will be found in a large

percentage of patients

Clinical scenarios

Pt. continued to bleed with hypotension and tachycardia. Patient requires 2 units of PRBCs

Pt. stopped bleeding. Vitals normalizes

Options to diagnose and control the bleeding

RBC scan, requires 0.5-1 ml/min bleeding

Mesenteric angiography, requires 1-1.5 ml/min bleeding

Colonoscopy Surgery Meckels scan

Scenario one- Pt. continues to bleed

and is unstable.

Rbc scan vs colonoscopy

COLONOSCOPY

Colonoscopy is undoubtedly the best test for confirming the source of LGIB and for excluding ominous diagnoses, such as malignancy.

The diagnostic yield of colonoscopy ranges from 45% to 95% Perform after golytely prep(w/in 12-24h) Identifies lesion in 75 % or more Can provide endoscopic therapy Early colonoscopy associated with reduced stay Complications 0.5-1 % most patients undergoing radiographic evaluation for LGIB

regardless of findings and interventions will subsequently require

a colonoscopy to establish the cause of bleeding.

URGENT COLONOSCOPY Jensen et al

Reduced rate of rebleeding and emergency surgery from diverticular bleed when compared to historical controls

Green et al100 randomized to urgent (w/in 8hrs)

colonoscopy to standard careDefinitive source more common in urgent

group No difference in multiple clinical outcomes

Issue is still not resolved

CLINICAL SCENARIO

Patient continues to bleed RBC scan is positive on the left side?

How much true this information is?? What to do next? surgery, ?angio with

embolization?

RADIONUCLIDE SCAN radionuclide scanning has variable accuracy, cannot confirm the

source of bleeding, and may delay other diagnostic and therapeutic procedures.

Correct localization rate is 41-100% Accuracy appears to be best when the scan becomes positive within a

short period of time In one study, 42% of patients underwent an incorrect surgical

procedure based on scintigraphy results. In addition, several studies have found that regardless of accuracy, scintigraphy did not affect surgical management

Predictors of positive response-hemodynamic instability= 62% vs. 21%

->2units transfused within 24 hrs= 64% vs. 32%

CLINICAL SCENARIO

Patient underwent angiogram with embolization

Vitals improved What are the chances that pt. will

rebleed? Colonoscopy?

MESENTERIC ANGIOGRAM Selective embolization initially controls

hemorrhage in up to 100% of patients, but rebleeding rates are 15% to 40%

Advantages:-Precise localization-Can provide therapy with intra-arterial vasopressin or coil embolization-Procedure of choice in briskly bleeding pts-Minor complication rate of 9% and a 0% major complication rate

Disadvantages:-Invasive

-Less sensitive in detecting venous bleeding

-Can cause ischemia, contrast reactions, arterial injury

Advantages and disadvantages of common diagnostic procedures used in the evaluation of lower gastrointestinal bleeding

Procedure Advantages Disadvantages

Colonoscopy • Therapeutic possibilities • Bowel preparation required

• Diagnostic for all sources of bleeding

• Can be difficult to orchestrate without on-call endoscopy facilities or staff

• Needed to confirm diagnosis in most patients regardless of initial testing

• Invasive

• Efficient/cost-effective

Angiography • No bowel preparation needed • Requires active bleeding at the time of the exam

• Therapeutic possibilities • Less sensitive to venous bleeding

• May be superior for patients with severe bleeding

• Diagnosis must be confirmed with endoscopy/surgery

• Serious complications are possible

Radionuclide scintigraphy

• Noninvasive • Variable accuracy (false positives)

• Sensitive to low rates of bleeding • Not therapeutic

• No bowel preparation • May delay therapeutic intervention

• Easily repeated if bleeding recurs • Diagnosis must be confirmed with endoscopy/surgery

Flexible sigmoidoscopy

• Diagnostic and therapeutic • Visualizes only the left colon

• Minimal bowel preparation • Colonoscopy or other test usually necessary to rule out right-sided lesions

• Easy to perform

Pt. under went colonoscopy for definitive diagnosis.

In how many patients there will be more than one potential diagnosis?

In how many patients there will be no diagnosis found?

ETIOLOGYDifferential Diagnosis of Lower Gastrointestinal Hemorrhage

COLONIC BLEEDING (95%) % SMALL BOWEL BLEEDING (5%)

Diverticular disease 30-40 Angiodysplasias

Ischemia 5-10 Erosions or ulcers (potassium, NSAIDs)

Anorectal disease 5-15 Crohn's disease

Neoplasia 5-10 Radiation

Infectious colitis 3-8 Meckel's diverticulum

Postpolypectomy 3-7 Neoplasia

Inflammatory bowel disease 3-4 Aortoenteric fistula

Angiodysplasia 3

Radiation colitis/proctitis 1-3

Other 1-5

Unknown 10-25

DIAGNOSTIC DIFFICULTIES

When compared with EGD for upper GI bleeding, the diagnostic modalities for lower GI bleeding are not as sensitive or specific in making an accurate diagnosis.

Diagnostic evaluation is further complicated by the observation that, in up to 40% of patients with lower GI bleeding, more than one potential source of hemorrhage is identified.

If more than one source is identified, it is critical to confirm the responsible lesion before initiating aggressive therapy.

This approach may occasionally require a period of observation with several episodes of bleeding before a definitive diagnosis can be made.

In fact, in up to 25% of patients with lower GI hemorrhage, the bleeding source is never accurately identified.

CLINICAL SCENARIO

COLONOSCOPY SHOWEDold and BRB in mid colon

tics seen throughout Dx= probably diverticular beed Pt was d/c home

CLINICAL SCENARIO

2 wks later readmitted with rebleed and syncope

Hct 32--- 24 Urgent tagged RBC scan – neg Deep mid AC diverticulum with clot that

could not be removed What is the next step

SURGERY Surgery usually is employed for hemorrhage in two settings:

massive or recurrent bleeding. It is required in 15% to 25% of patients who have diverticular

bleeding and is recommended for patients with a high transfusion requirement (generally more than four units within a 24-hour period or greater than 10 units total)

Recurrent bleeding from diverticula occurs in 20% to 40% of patients and generally is considered an indication for surgery

In patients with serious comorbid medical conditions and without exsanguinating hemorrhage, this decision should be made carefully.

Great effort should be made to accurately localize the site of bleeding preoperatively so that segmental rather than subtotal colectomy can be performed Operative mortality is 10% even with accurate localization and up to 57% with blind subtotal colectomy.