Early predictors of severe lower gastrointestinal bleeding and adverse outcomes: a prospective study

Intra-arterial treatment in patients with acute massive gastrointestinal bleeding after endoscopic failure: comparisons between positive versus negative contrast extravasation groups

Objective

To determine whether treatment outcome is associated with visualization of contrast extravasation in patients with acute massive gastrointestinal bleeding after endoscopic failure.

Materials and Methods

From January 2007 to December 2009, patients that experienced a first attack of acute gastrointestinal bleeding after failure of initial endoscopy were referred to our interventional department for intra-arterial treatment. We enrolled 79 patients and divided them into two groups: positive and negative extravasation. For positive extravasation, patients were treated by coil embolization; and in negative extravasation, patients were treated with intra-arterial vasopressin infusion. The two groups were compared for clinical parameters, hemodynamics, laboratory findings, endoscopic characteristics, and mortality rates.

Results

Forty-eight patients had detectable contrast extravasation (positive extravasation), while 31 patients did not (negative extravasation). Fifty-six patients survived from this bleeding episode (overall clinical success rate, 71%). An elevation of hemoglobin level was observed in the both two groups; significantly greater in the positive extravasation group compared to the negative extravasation group. Although these patients were all at high risk of dying, the 90-day mortality rate was significantly lower in the positive extravasation than in the negative extravasation (20% versus 42%, p < 0.05). A multivariate analysis suggested that successful hemostasis (odds ratio [OR] = 28.66) is the most important predictor affecting the mortality in the two groups of patients.

Conclusion

Visualization of contrast extravasation on angiography usually can target the bleeding artery directly, resulting in a higher success rate to control of hemorrhage.

Impact of upper and lower gastrointestinal blood loss on healthcare utilization and costs: a systematic review

OBJECTIVES

Gastrointestinal (GI) blood loss is a common medical condition which can have serious morbidity and mortality consequences and may pose an enormous burden on healthcare utilization. The purpose of this study was to conduct a systematic review to evaluate the impact of upper and lower GI blood loss on healthcare utilization and costs.

METHODS

We performed a systematic search of peer-reviewed English articles from MEDLINE published between 1990 and 2010. Articles were limited to studies with patients ≥18 years of age, non-pregnant women, and individuals without anemia of chronic disease, renal disease, cancer, congestive heart failure, HIV, iron-deficiency anemia or blood loss due to trauma or surgery. Two reviewers independently assessed abstract and article relevance.

RESULTS

Eight retrospective articles were included which used medical records or claims data. Studies analyzed resource utilization related to medical care although none of the studies assessed indirect resource use or costs. All but one study limited assessment of healthcare utilization to hospital use. The mean cost/hospital admission for upper GI blood loss was reported to be in the range $3180-8990 in the US, $2500-3000 in Canada and, in the Netherlands, the mean hospital cost/per blood loss event was €11,900 for a bleeding ulcer and €26,000 for a bleeding and perforated ulcer. Mean cost/ hospital admission for lower GI blood loss was $4800 in Canada, and $40,456 for small bowel bleeding in the US.

CONCLUSIONS

Our findings suggest that the impact of GI blood loss on healthcare costs is substantial but studies are limited. Additional investigations are needed which examine both direct and indirect costs as well as healthcare costs by source of GI blood loss focusing on specific populations in order to target treatment pathways for patients with GI blood loss.

Randomized trial of urgent vs. elective colonoscopy in patients hospitalized with lower GI bleeding

OBJECTIVES

We sought to determine, in patients with serious hematochezia, the proportion who have an upper gastrointestinal (GI) source and whether urgent colonoscopy improves outcomes as compared with elective colonoscopy in those without an upper source.

METHODS

Patients with hematochezia were eligible if they also had heart rate >100, systolic blood pressure <100, orthostatic change in heart rate or blood pressure >20, hemoglobin drop ≥ 1.5 g/dl, or blood transfusion. Patients had upper endoscopy within 6 h. Those without an upper source were randomized to urgent (≤ 12 h) or elective (36-60 h after presentation) colonoscopy. The primary end point was further bleeding. Patients were followed for the duration of hospitalization.

RESULTS

Eighty-five eligible patients had urgent upper endoscopy; 13 (15%) had an upper source. The remaining 72 were randomized to urgent (N=36) or elective (N=36) colonoscopy. Further bleeding occurred in 8 (22%) vs. 5 (14%) of the urgent vs. elective groups (difference=8%, 95% confidence interval (CI)=-9 to 26%). Units of blood (1.5 vs. 0.7), hospital days (5.2 vs. 4.8), subsequent diagnostic or therapeutic interventions for bleeding (36% vs. 33%), and hospital charges ($27,590 vs. $26,633) also were not lower in the urgent group. A major limitation is that the study was terminated before reaching the prespecified sample size.

CONCLUSIONS

Patients with clinically serious hematochezia should have upper endoscopy initially to rule out an upper GI source. Use of urgent colonoscopy in a population hospitalized with serious lower GI bleeding showed no evidence of improving clinical outcomes or lowering costs as compared with routine elective colonoscopy.

Editorial: Urgent colonoscopy in lower GI bleeding: not so fast

The role of urgent colonoscopy in lower gastrointestinal bleeding (LGIB) remains controversial. Although some studies have shown that examinations performed within 12-24 h of admission improve diagnostic yield and reduce rebleeding and surgery, others have not. In this issue of the American Journal of Gastroenterology, Laine and Shah present a randomized trial of urgent (<12 h from admission) vs. elective (36-60 h from admission) colonoscopy in 72 patients with LGIB. A total of 15% of patients with presumed LGIB were found to have upper gastrointestinal bleeding, highlighting the importance of excluding a gastroduodenal source in patients with severe hematochezia. The majority of patients with LGIB (72%) stopped bleeding spontaneously, and there were no differences in rebleeding, blood transfusions, diagnostic or therapeutic interventions, length of hospital stay, or hospital charges in patients undergoing urgent vs. elective colonoscopy. However, the limited number of patients in this study and the fact that patients in the urgent colonoscopy arm appeared to have more severe bleeding than those undergoing elective examinations make it difficult to draw conclusions regarding the utility of urgent vs. elective colonoscopy in LGIB.

The role of colonoscopy and radiological procedures in the management of acute lower intestinal bleeding

There are multiple strategies for evaluating and treating lower intestinal bleeding (LIB). Colonoscopy has become the preferred initial test for most patients with LIB because of its diagnostic and therapeutic capabilities and its safety. However, few studies have directly compared colonoscopy with other techniques and there are controversies regarding the optimal timing of colonoscopy, the importance of colon preparation, the prevalence of stigmata of hemorrhage, and the efficacy of endoscopic hemostasis. Angiography, radionuclide scintigraphy, and multidetector computed tomography scanning are complementary modalities, but the requirement of active bleeding at the time of the examination limits their routine use. In addition, angiography can result in serious complications. This review summarizes the available evidence regarding colonoscopy and radiographic studies in the management of acute LIB.

Video capsule endoscopy in life-threatening GI hemorrhage after negative primary endoscopy (with video)

BACKGROUND

Video capsule endoscopy (VCE) continues to evolve as a key diagnostic tool. Traditionally VCE has been used to detect occult and obscure GI bleeding in adult patients. VCE has not been documented or accepted as an early diagnostic tool for acute life-threatening GI hemorrhage.

OBJECTIVE

Our purpose was to demonstrate the use of VCE as an early diagnostic tool in acute life-threatening GI hemorrhage.

DESIGN

Case series.

PATIENTS

Patients with life-threatening GI hemorrhage.

INTERVENTIONS

VCE after negative primary endoscopy.

RESULTS

VCE allowed rapid diagnosis and reliable data before surgical intervention. Although proving to be a beneficial diagnostic tool for acute GI hemorrhage, VCE was not associated with increased morbidity or mortality rates.

LIMITATIONS

This report only focuses on cases where VCE successfully led to a diagnosis. There is no prospective control group to which these patients can be compared. There were no other attempted acute VCE studies in patients with life-threatening bleeding during the time period of these case reports.

CONCLUSIONS

The use of VCE is a simple and relatively safe diagnostic tool in the evaluation of continuing GI hemorrhaging in endoscopy-negative patients. The use of VCE can be considered as a another useful tool in the armamentarium of the endoscopist in the evaluation of GI bleeding. Prospective studies should be undertaken to determine the appropriate timing and clinical use in this group of patients.

Gross lower gastrointestinal bleeding in patients on anticoagulant and/or antiplatelet therapy: endoscopic findings, management, and clinical outcomes

OBJECTIVES

Gross gastrointestinal (GI) bleeding is a serious complication of anticoagulant/antiplatelet drug therapy. This study compares the frequencies of colorectal pathologies, endoscopic and resuscitative management measures, and clinical outcomes of patients hospitalized with lower GI bleeding (LGIB) while using anticoagulants/antiplatelets with those of patients not using them.

METHODS

A retrospective review of the records of 166 admissions for patients with gross LGIB over 12 years was conducted. The colonoscopic findings, management measures, and clinical outcomes were compared between 2 groups. Group A composed of 100 patients using any antiplatelet/anticoagulant, and group B 66 patients not using any such drugs. Independent t tests and chi were used to test for association between taking antiplatelet/anticoagulant and other variables.

RESULTS

Patients in group A were older and had more comorbidities than patients in group B. Severe LGIB occurred in 55.1% and 35.4% in groups A and B, respectively (P=0.01). Severity was not related to old age or the presence of comorbidities. A higher percentage of patients in group A had a hospital stay > or =6 days (44% vs. 27.3%; P<0.03), required blood transfusions (68% vs. 51.5%; P=0.03), and had in-hospital complications (37% vs. 22.7%; P=0.052). The most common source of bleeding was diverticulosis in both groups. Colorectal abnormalities were present in most patients; and in those using warfarin, colon cancer was common.

CONCLUSIONS

Use of antiplatelets/anticoagulant drugs is an independent predictor of severe LGIB and is associated with adverse outcomes. Colonoscopy is required in patients who bleed while using such drugs.

Risk factors for mortality in lower intestinal bleeding

BACKGROUND & AIMS

Previous studies of lower intestinal bleeding (LIB) have limited power to study mortality. We sought to identify characteristics associated with in-hospital mortality in a large cohort of patients with LIB.

METHODS

We used the 2002 Healthcare Cost and Utilization Project Nationwide Inpatient Sample to study a cross-sectional cohort of 227,022 hospitalized patients with discharge diagnoses indicating LIB. Predictors of mortality were identified by using multiple logistic regression.

RESULTS

In 2002, an estimated 8737 patients with LIB (3.9%) died while hospitalized. Independent predictors of in-hospital mortality were age (age >70 vs <50 years; odds ratio [OR], 4.91; 95% confidence interval [CI], 2.45-9.87), intestinal ischemia (OR, 3.47; 95% CI, 2.57-4.68), comorbid illness (>or=2 vs 0 comorbidities, OR, 3.00; 95% CI, 2.25-3.98), bleeding while hospitalized for a separate process (OR, 2.35; 95% CI, 1.81-3.04), coagulation defects (OR, 2.34; 95% CI, 1.50-3.65), hypovolemia (OR, 2.22; 95% CI, 1.69-2.90), transfusion of packed red blood cells (OR, 1.60; 95% CI, 1.23-2.08), and male gender (OR, 1.52; 95% CI, 1.21-1.92). Colorectal polyps (OR, 0.26; 95% CI, 0.15-0.45), and hemorrhoids (OR, 0.42; 95% CI, 0.28-0.64) were associated with a lower risk of mortality, as was diagnostic testing for LIB when added to the multivariate model (OR, 0.37; 95% CI, 0.28-0.48). Hospital characteristics were not significantly related to mortality. Predictors of mortality were similar in an analysis restricted to patients with diverticular bleeding.

CONCLUSIONS

The all-cause in-hospital mortality rate in LIB was low (3.9%). Advanced age, intestinal ischemia, and comorbid illness were the strongest predictors of mortality.

Clinical risk stratification for gastrointestinal hemorrhage: still no consensus

A lack of consensus exists in the pre-endoscopic risk stratification of patients with upper or lower gastrointestinal hemorrhage. The work by Das and colleagues in the previous issue of Critical Care serves to externally validate the BLEED criteria. Their results suggest that hemodynamically stable patients without evidence of ongoing bleeding or unstable comorbidities may be at lower risk for hospital complications. While their results reinforce previous studies, further investigation is needed before comprehensive practice guidelines can be established.

Epidemiology of lower gastrointestinal bleeding

Lower GI bleeding is a very broad topic, which can encompass situations from a small amount of red blood on tissue paper associated with formed brown stool, to life-threatening severe haemorrhage. Much of the literature on this topic focuses on acute bleeding necessitating hospitalisation and urgent intervention. The literature that is available focuses primarily on medical intervention and support, which will be covered in another review in this series. Causes for lower GI bleeding include diverticular disease, vascular ectasia, ischemic, inflammatory or infectious colitis, colonic neoplasia (including post polypectomy bleeding), anorectal causes (including haemorrhoids, fissures and rectal varices), and small bowel lesions (Crohn's, vascular ectasia, Meckel's diverticula, and small bowel tumours). Different clinical series identified these lesions in varying frequencies. Factors associated with the development of acute lower GI bleeding include advanced age and use of non-steroidal anti-inflammatory medication. Colonoscopy is the single most frequent intervention in evaluating all the patients with lower GI bleeding. Determining the precise impact of colonoscopy on the outcome of lower GI bleeding is difficult due to the retrospective nature of many studies, and the frequent inability to definitively establish the exact bleeding site.

Management of lower gastrointestinal tract bleeding

Acute bleeding from the colon and rectum is less frequent and less dramatic than haemorrhage from the upper gastrointestinal tract. In most cases, bleeding from the colon and rectum is self-limiting and requires no specific therapy. Diverticula and angiectasias are the most frequent sources of bleeding. Malignancy, colitis (inflammatory bowel disease, non-steroidal anti-inflammatory drugs, and infectious colitis), ischaemia, anorectal disorders, postpolypectomy bleeding, and HIV-related problems are less frequent causes. The recurrence rate, especially in diverticular bleeding, is high. Resuscitation and haemodynamic stabilisation of the patient is the first step in the management of colonic bleeding. Urgent colonoscopy is the method of choice for diagnosis and therapy. By analogy with peptic ulcer bleeding, risk stratification using stigmata of haemorrhage is gaining more importance. Modern endoscopic techniques such as injection therapy, thermocoagulation and mechanical devices seem to be effective in achieving haemostasis and avoiding precarious surgery. Angiography and nuclear scintigraphy are reserved for those patients in whom colonoscopy is not possible or has repeatedly failed to localise the bleeding site.

A decision support system to facilitate management of patients with acute gastrointestinal bleeding

OBJECTIVE

To develop a model to predict the bleeding source and identify the cohort amongst patients with acute gastrointestinal bleeding (GIB) who require urgent intervention, including endoscopy. Patients with acute GIB, an unpredictable event, are most commonly evaluated and managed by non-gastroenterologists. Rapid and consistently reliable risk stratification of patients with acute GIB for urgent endoscopy may potentially improve outcomes amongst such patients by targeting scarce healthcare resources to those who need it the most.

DESIGN AND METHODS

Using ICD-9 codes for acute GIB, 189 patients with acute GIB and all available data variables required to develop and test models were identified from a hospital medical records database. Data on 122 patients was utilized for development of the model and on 67 patients utilized to perform comparative analysis of the models. Clinical data such as presenting signs and symptoms, demographic data, presence of co-morbidities, laboratory data and corresponding endoscopic diagnosis and outcomes were collected. Clinical data and endoscopic diagnosis collected for each patient was utilized to retrospectively ascertain optimal management for each patient. Clinical presentations and corresponding treatment was utilized as training examples. Eight mathematical models including artificial neural network (ANN), support vector machine (SVM), k-nearest neighbor, linear discriminant analysis (LDA), shrunken centroid (SC), random forest (RF), logistic regression, and boosting were trained and tested. The performance of these models was compared using standard statistical analysis and ROC curves.

RESULTS

Overall the random forest model best predicted the source, need for resuscitation, and disposition with accuracies of approximately 80% or higher (accuracy for endoscopy was greater than 75%). The area under ROC curve for RF was greater than 0.85, indicating excellent performance by the random forest model.

CONCLUSION

While most mathematical models are effective as a decision support system for evaluation and management of patients with acute GIB, in our testing, the RF model consistently demonstrated the best performance. Amongst patients presenting with acute GIB, mathematical models may facilitate the identification of the source of GIB, need for intervention and allow optimization of care and healthcare resource allocation; these however require further validation.

Prediction of outcome in acute lower gastrointestinal hemorrhage: role of artificial neural network

Acute lower gastrointestinal hemorrhage (LGIH) has traditionally been defined as bleeding that occurs distal to the ligament of Treitz. More recently, however, it has been subdivided into mid-intestinal (small bowel) hemorrhage and bleeding that originates from the colon. Acute LGIH has diverse etiologies, is a frequent cause of hospital admission, and is associated with significant patient morbidity and mortality, as well as substantial economic cost. In contrast to hemorrhage from the upper gastrointestinal tract (UGIH), the management of acute LGIH is less well defined; furthermore, there is a paucity of published studies that evaluate predictive models in this disorder. Nonetheless, extrapolating from what is known in UGIH, the development of reliable predictive models in LGIH may lead to improved patient care and outcome, by enhancing clinical triage, and by the more cost-effective use of limited healthcare resources. In this review, we discuss the technical development and potential use of artificial neural network in patients presenting with acute LGIH.

Lower gastrointestinal bleeding: a review

Lower gastrointestinal bleeding (LGIB) continues to be a problem for physicians. Acute LGIB is defined as bleeding that emanates from a source distal to the ligament of Treitz. Although 80% of all LGIB will stop spontaneously, the identification of the bleeding source remains challenging and rebleeding can occur in 25% of cases. Some patients with severe hematochezia require urgent attention to minimize further bleeding and complications. This article reviews the causes, diagnostic methods, and endoscopic treatment of LGIB.

Severe acute lower gastrointestinal bleeding: risk factors for morbidity and mortality

BACKGROUND

Many factors can cause morbidity and mortality in patients with severe acute lower gastrointestinal bleeding (LGIB). The objectives of this study are to analyze three aspects related to severe acute LGIB: (1) indications and prognostic factors for urgent surgery, (2) risk factors for morbidity and mortality, and (3) relapse rates.

PATIENTS AND METHODS

A retrospective cohort was collected between 1985 and 2002 in a tertiary referral center. One hundred seventy-one patients with severe acute LGIB were reviewed (LGIB is defined as frank rectal bleeding either with a hematocrit decrease >/=10 points or when a transfusion of at least three units of concentrated red blood cells is needed). The main outcome measures are: (1) indications for urgent surgery and results, (2) morbidity and mortality, and (3) relapse.

RESULTS

There were 158 (92%) stable patients, and in 61% of these, the bleeding was identified via colonoscopy. Bleeding was identified using urgent colonoscopy in a higher percentage of patients compared to delayed colonoscopy (68% versus 14%; p < 0.001). Urgent surgery was indicated in 24 (14%) patients, and the approach was peri-anal in 5 (21%) patients and abdominal in the rest. Local intestinal resection was performed on the 15 patients in which bleeding was identified, whereas a subtotal colectomy was performed on the remaining 4 patients. The presence of hypotension (p = 0.001; 35 versus 10%) and etiology of LGIB (p < 0.001) are prognostic factors of urgent surgery. Morbidity was 6.4%, and mortality was 4.7%. The only morbidity or mortality risk factors detected were the presence of associated comorbidities (p = 0.008) and the need for urgent surgery (p = 0.002). The most frequent etiology was diverticulosis (25%). After a mean follow-up of 132 +/- 75 months, bleeding relapsed in 30% of patients.

CONCLUSIONS

It is difficult to predict which patients are going to need urgent surgery in severe acute LGIB; only the presence of hypotension on arrival at the emergency ward would lead us to suspect a negative outcome for the hemorrhage. In severe acute LGIB, morbidity and mortality is high, and this is mainly due to the high level of associated comorbidity and the need for urgent surgery. It is necessary for strict hemodynamic monitoring of the patients at risk if we want to improve outcomes. The bleeding relapse rate is high in LGIB, although generally, it is not severe.

[Management of rectorrhagia having uncertain origin]

Rectorrhagia is a very frequent reason for hospital and Primary Health Care medical visits. Its main problem is that it is made up of a very heterogeneous group of patients and a correct diagnosis is difficult to make. The main diagnostic test is the colonoscopy, and in severe cases, the arteriography. When these examinations do not provide the diagnosis, small intestine disease should be suspected. In most of the cases, rectorrhagia abates spontaneously or is controlled with conservative measures, and the subsequent treatment with depend on the etiology that caused the bleeding. The great problem arises in 0.5%-4% of rectorrhagies that do not abate and unstabilize the patient, emergency surgery due to the bleeding being required.

Lower gastrointestinal bleeding--management

Although acute LGIB is only about one fifth as common and is usually less hemodynamically significant than upper gastrointestinal bleeding, it presents numerous unique clinical challenges. The best diagnostic approach for patients with active bleeding is unknown, but urgent prepared colonoscopy is safe and likely to be beneficial (Fig. 3, Table 2). In patients who have aggressive bleeding or recurrent bleeding, it is critical for the practitioner to judge when angiography and surgery are necessary.

Lower GI bleeding: epidemiology and diagnosis

Lower gastrointestinal bleeding is one of the most common gastrointestinal indications for hospital admission, particularly in the elderly. Diverticulosis accounts for up to 50% of cases, followed by ischemic colitis and anorectal lesions. Though most patients stop bleeding spontaneously and have favorable outcomes, long-term recurrence is a substantial problem for patients with bleeding from diverticulosis and angiodysplasia. The management of LGIB is challenging because of the diverse range of bleeding sources, the large extent of bowel involved, the intermittent nature of bleeding, and the various complicated and often invasive investigative modalities. Advances in endoscopic technology have brought colonoscopy to the forefront of the management of LGIB. However, many questions remained to be answered about its usefulness in routine clinical practice. More randomized controlled trials comparing available diagnostic strategies for LGIB are needed.

Validation of a clinical prediction rule for severe acute lower intestinal bleeding

OBJECTIVES

Acute lower intestinal bleeding is a heterogeneous disorder and identification of high-risk patients is challenging. We previously retrospectively identified predictors of severity in patients with acute lower intestinal bleeding. The aim of this study was to prospectively validate a clinical prediction rule for severe acute lower intestinal bleeding.

METHODS

This was a prospective, observational cohort study of consecutive patients admitted to an academic, tertiary care or a community-based teaching hospital for management of acute lower intestinal bleeding. Data were collected on seven previously identified predictors of severe bleeding: heart rate > or = 100/min, systolic blood pressure < or = 115 mmHg, syncope, nontender abdominal exam, rectal bleeding in the first 4 h of evaluation, aspirin use, and >2 comorbid conditions. Severe bleeding was defined as transfusion of > or =2 units of red blood cells, and/or a decrease in hematocrit of > or =20% in the first 24 h, and/or recurrent rectal bleeding after 24 h of stability (accompanied by a further decrease in hematocrit of > or =20%, and/or additional blood transfusions, and/or readmission for acute lower intestinal bleeding within 1 wk of discharge). Patients were stratified into 3 risk groups according to the previously developed prediction rule: low (no risk factors), moderate (1-3 risk factors), and high (>3 risk factors).

RESULTS

A total of 275 patients with acute lower intestinal bleeding were identified. The risk of severe bleeding in each risk category was similar in the validation and derivation cohorts (p values >0.05): low risk 6%versus 9%, moderate risk 43%versus 43%, and high risk 79%versus 84%. The area under the receiver operating characteristic curve was 0.754 for the validation cohort and 0.761 for the derivation cohort. The magnitude of the risk score was significantly correlated with major clinical outcomes including surgery, death, blood transfusions, and length of stay.

CONCLUSION

We have developed and prospectively validated a clinical prediction rule for acute severe lower intestinal bleeding. This prediction rule could improve the triage of patients to appropriate levels of care and interventions, and guide a more standardized approach to acute lower intestinal bleeding.

Review article: the management of lower gastrointestinal bleeding

Several recent advances have been made in the evaluation and management of acute lower gastrointestinal bleeding. This review focuses on the management of lower gastrointestinal bleeding, especially acute severe bleeding. The aim of the study was to critically review the published literature on important management issues in lower gastrointestinal bleeding, including haemodynamic resuscitation, diagnostic evaluation, and endoscopic, radiologic, and surgical therapy, and to develop an algorithm for the management of lower gastrointestinal bleeding, based on this literature review. Publications pertaining to lower gastrointestinal bleeding were identified by searches of the MEDLINE database for the years 1966 to December 2004. Clinical trials and review articles were specifically identified, and their reference citation lists were searched for additional publications not identified in the database searches. Clinical trials and current clinical recommendations were assessed by using commonly applied criteria. Specific recommendations are made based on the evidence reviewed. Approximately, 200 original and review articles were reviewed and graded. There is a paucity of high-quality evidence to guide the management of lower gastrointestinal bleeding, and current endoscopic, radiologic, and surgical practices appear to reflect local expertise and availability of services. Endoscopic literature supports the role of urgent colonoscopy and therapy where possible. Radiology literature supports the role of angiography, especially after a positive bleeding scan has been obtained. Limited surgical data support the role of segmental resection in the management of persistent lower gastrointestinal bleeding after localization by either colonoscopy or angiography. There is limited high-quality research in the area of lower gastrointestinal bleeding. Recent advances have improved the endoscopic, radiologic and surgical management of this problem. However, treatment decisions are still often based on local expertise and preference. With increased access to urgent therapeutic endoscopy for the management of acute upper gastrointestinal bleeding, diagnostic and therapeutic colonoscopy can be expected to play an increasing role in the management of acute lower gastrointestinal bleeding.

Endoscopic Approach to the Treatment of Gastrointestinal Bleeding

Gastrointestinal endoscopy is the primary diagnostic and therapeutic modality in the management of gastrointestinal bleeding. Esophagogastroduodenoscopy, small bowel enteroscopy, and colonoscopy are well-established standards for initial evaluation of gastrointestinal bleeding, and have been used effectively for diagnosis, prognosis, and therapy. Although thermal, injection, and mechanical methods have been the mainstay of endoscopic therapy, promising new technologies such as endoscopic ultrasound and wireless capsule endoscopy will further advance our ability to improve morbidity and mortality from severe gastrointestinal hemorrhage. Herein we review current standards and recent advances in the endoscopic management of upper, lower, and obscure gastrointestinal bleeding.

The clinical utility of nuclear medicine imaging for the detection of occult gastrointestinal haemorrhage

Acute gastrointestinal bleeding is often intermittent and the bleeding source may be difficult to locate, resulting in delay of potentially life-saving treatment. The aim of this study was to determine the clinical utility of 99mTc labelled red blood cell imaging and [99mTc]pertechnetate (Meckel's scan) imaging in a series of 137 patients admitted over a 5 year period to hospital for management of acute gastrointestinal bleeding. Of the 137 patients, 70 had positive 99mTc red blood cell studies. Eleven of 24 patients who had imaging performed beyond 3 h had positive scans that would otherwise have been missed. Only 47 patients had a definite final diagnosis at the time of hospital discharge, of which six were negative on 99mTc red blood cell imaging. The correct site of bleeding was localized in seven of 21 patients with foregut bleeding, and 15 of 20 patients with colonic bleeding. Endoscopy yielded a diagnosis in 13 of the 47 patients (28%). Eleven patients had Meckel's scans but all were negative. Angiography was diagnostic in one of 17 patients studied. 99mTc red blood cell imaging is a useful test in the management of acute gastrointestinal bleeding. Imaging beyond 3 h may further improve the bleeding detection rate. This test, however, may be an unreliable means of localization of bleeding, particularly in the foregut.