Clinical variables associated with positive angiographic localization of lower gastrointestinal bleeding

Twenty years of embolization for acute lower gastrointestinal bleeding: a meta-analysis of rebleeding and ischaemia rates

BACKGROUND

Transarterial embolization (TAE) for acute lower gastrointestinal bleeding (LGIB) can be technically challenging due to the compromise between achieving haemostasis and causing tissue ischaemia. The goal of the present study is to determine its technical success, rebleeding, and post-embolization ischaemia rates through meta-analysis of published literature in the last twenty years.

METHODS

PubMed, Embase, and Cochrane Library databases were queried. Technical success, rebleeding, and ischaemia rates were extracted. Baseline characteristics such as author, publication year, region, study design, embolization material, percentage of superselective embolization were retrieved. Subgroup analysis was performed based on publication time and embolization agent.

RESULTS

A total of 66 studies including 2121 patients who underwent embolization for acute LGIB were included. Endoscopic management was attempted in 34.5%. The pooled overall technical success, rebleeding, post-embolization ischaemia rates were 97.0%, 20.7%, and 7.5%, respectively. Studies published after 2010 showed higher technical success rates (97.8% vs 95.2%), lower rebleeding rates (18.6% vs 23.4%), and lower ischaemia rates (7.3% vs 9.7%). Compared to microcoils, NBCA was associated with a lower rebleeding rate (9.3% vs 20.8%) at the expense of a higher post-embolization ischaemia rate (9.7% vs 4.0%). Coagulopathy (P = .034), inotropic use (P = .040), and malignancy (P = .002) were predictors of post-embolization rebleeding. Haemorrhagic shock (P < .001), inotropic use (P = .026), malignancy (P < .001), coagulopathy (P = .002), blood transfusion (P < .001), and enteritis (P = .023) were predictors of mortality. Empiric embolization achieved a similarly durable haemostasis rate compared to targeted embolization (23.6% vs 21.1%) but a higher risk of post-embolization ischaemia (14.3% vs 4.7%).

CONCLUSION

For LGIB, TAE has a favourable technical success rate and low risk of post-embolization ischaemia. Its safety and efficacy profile has increased over the last decade. Compared to microcoils, NBCA seemed to offer a more durable haemostasis rate at the expense of higher ischaemia risk. Due to the heterogeneity of currently available evidence, future prospective and comparative studies are warranted.

ADVANCES IN KNOWLEDGE

(1) Acute LGIB embolization demonstrate a high technical success rate with acceptable rate of rebleeding and symptomatic ischaemia rates. Most ischaemic stigmata discovered during routine post-embolization colonoscopy were minor. (2) Although NBCA seemed to offer a more durable haemostasis rate, it was also associated with a higher risk of ischaemia compared to microcoils. (3) Coagulopathy, malignant aetiology, and inotropic use were predictors of rebleeding and mortality. (4) Routine post-embolization endoscopy to assess for ischaemia is not indicated.

Variceal and Nonvariceal Upper Gastrointestinal Bleeding Refractory to Endoscopic Management: Indications and Role of Interventional Radiology

For over 60 years, diagnostic and interventional radiology have been heavily involved in the evaluation and treatment of patients presenting with gastrointestinal bleeding. For patients who present with upper GI bleeding and have a contraindication to endoscopy or have an unsuccessful attempt at endoscopy for identifying or controlling the bleeding, interventional radiology is often consulted for evaluation and consideration of catheter-based intervention.

Review article: Advances in the management of lower gastrointestinal bleeding

BACKGROUND

Lower gastrointestinal bleeding (LGIB) is a common emergency with substantial associated morbidity and mortality. Elective colonoscopy plays an essential role in management, with an even more important role for radiology in the acute setting. Recent advances in the management of patients with LGIB warrant review as the management has recently evolved.

AIMS

To provide a comprehensive and updated overview of advances in the approach to patients with LGIB METHODS: We performed a comprehensive literature search to examine the current data for this narrative review supplemented by expert opinion.

RESULTS

The incidence of LGIB is increasing worldwide, partly related to an ageing population and the increasing use of antithrombotics. Diverticulosis continues to be the most common aetiology of LGIB. Pre-endoscopic risk stratification tools, especially the Oakland score, can aid appropriate patient triage. Adequate resuscitation continues to form the basis of management, while appropriate management of antithrombotics is crucial to balance the risk of worsening bleeding against increased cardiovascular risk. Radiological imaging plays an essential role in the diagnosis and treatment of acute LGIB, especially among unstable patients. Colonoscopy remains the gold-standard test for the elective management of stable patients.

CONCLUSIONS

The management of LGIB has evolved significantly in recent years, with a shift towards radiological interventions for unstable patients while reserving elective colonoscopy for stable patients. A multidisciplinary approach is essential to optimise the outcomes of patients with LGIB.

One in four patients with gastrointestinal bleeding develops shock or hemodynamic instability: A systematic review and meta-analysis

BACKGROUND

Hemodynamic instability and shock are associated with untoward outcomes in gastrointestinal bleeding. However, there are no studies in the existing literature on the proportion of patients who developed these outcomes after gastrointestinal bleeding.

AIM

To determine the pooled event rates in the available literature and specify them based on the bleeding source.

METHODS

The protocol was registered on PROSPERO in advance (CRD42021283258). A systematic search was performed in three databases (PubMed, EMBASE, and CENTRAL) on 14th October 2021. Pooled proportions with 95%CI were calculated with a random-effects model. A subgroup analysis was carried out based on the time of assessment (on admission or during hospital stay). Heterogeneity was assessed by Higgins and Thompson's I2 statistics. The Joanna Briggs Institute Prevalence Critical Appraisal Tool was used for the risk of bias assessment. The Reference Citation Analysis (https://www.referencecitationanalysis.com/) tool was applied to obtain the latest highlight articles.

RESULTS

We identified 11589 records, of which 220 studies were eligible for data extraction. The overall proportion of shock and hemodynamic instability in general gastrointestinal bleeding patients was 0.25 (95%CI: 0.17-0.36, I2 = 100%). In non-variceal bleeding, the proportion was 0.22 (95%CI: 0.14-0.31, I2 = 100%), whereas it was 0.25 (95%CI: 0.19-0.32, I2 = 100%) in variceal bleeding. The proportion of patients with colonic diverticular bleeding who developed shock or hemodynamic instability was 0.12 (95%CI: 0.06-0.22, I2 = 90%). The risk of bias was low, and heterogeneity was high in all analyses.

CONCLUSION

One in five, one in four, and one in eight patients develops shock or hemodynamic instability on admission or during hospitalization in the case of non-variceal, variceal, and colonic diverticular bleeding, respectively.

Gastrointestinal bleeding in von Willebrand patients: special diagnostic and management considerations

INTRODUCTION

Severe and recurrent gastrointestinal (GI) bleeding caused by angiodysplasia is a significant problem in patients with von Willebrand disease (VWD) and in those with acquired von Willebrand syndrome (AVWS). At present, angiodysplasia-related GI bleeding is often refractory to standard treatment including replacement therapy with von Willebrand factor (VWF) concentrates and continues to remain a major challenge and cause of significant morbidity in patients despite advances in diagnostics and therapeutics.

AREAS COVERED

This paper reviews the available literature on GI bleeding in VWD patients, examines the molecular mechanisms implicated in angiodysplasia-related GI bleeding, and summarizes existing strategies in the management of bleeding GI angiodysplasia in patients with VWF abnormalities. Suggestions are made for further research directions.

EXPERT OPINION

Bleeding from angiodysplasia poses a significant challenge for individuals with abnormal VWF. Diagnosis remains a challenge and may require multiple radiologic and endoscopic investigations. Additionally, there is a need for enhanced understanding at a molecular level to identify effective therapies. Future studies of VWF replacement therapies using newer formulations as well as other adjunctive treatments to prevent and treat bleeding will hopefully improve care.

Utility of CBCT and AVD for intraprocedural diagnosis and treatment of lower GI bleeding

BACKGROUND

Intraprocedural Cone Beam CT (CBCT) is assessed to examine if use improves diagnosis and embolization rates of acute lower GI bleed (LGIB) and if automatic vessel detection (AVD) software can identify feeding vessels (FV) for embolization.

METHODS

Patients with inconclusive DSA findings had CBCT and retrospective analysis with AVD software (Innova 3100, GE Company, USA). Technical success was defined as the ability to detect a lower GIB site while clinical success was defined as successful embolization without evidence of rebleeding or death within 30 days. AVD technical success was defined by the ability to identify the FV on both CTA and CBCT upon independent review by 3 blinded IRs, who also assigned a degree of certainty on a 5-point Likert scale.

RESULTS

74 patients in total were treated for lower GI bleed of which 34 had indeterminate DSA. Of those, 10 patients received DSA only, of which 1 was super selective. 24 patients with GIB on pre-procedural CTA and inconclusive DSA underwent CBCT. Use of CBCT identified 9 bleeds not seen on DSA and an additional source artery in 1 case representing a 42% change in intraprocedural management as all findings were embolized. When a bleed could not be identified on CBCT, but the FV could be identified on CTA, the same suspected FV could be selected on AVD 62% of the time with an average certainty of 4.0.

CONCLUSION

CBCT is useful in the intraprocedural detection of GIB when DSA is indeterminate. Furthermore, AVD software can feasibly be utilized to accurately identify FVs for empiric treatment when intraprocedural imaging is inconclusive.

LEVEL OF EVIDENCE

Level III, therapeutic study.

CT angiograms for lower GI bleeding: the experience of a large UK teaching hospital

INTRODUCTION

The clinical presentation of lower gastrointestinal bleeding (LGIB) is variable in severity, cause and potential investigations. The British Society of Gastroenterology recently published LGIB guidelines, recommending CT angiography (CT-A) for haemodynamically unstable patients, defined by shock index (SI) greater than 1. The aim of this study was to assess the use and role of CT-A in diagnosing LGIB, by assessing the pickup rate of active LGIB defined by contrast extravasation or 'blush' and to determine any association between positive CT-A with various patient and clinical characteristics.

METHODS

A retrospective analysis was carried out of 4 years of LGIB admissions. Demographics, inpatient observations and use of blood products were acquired. Vital signs nearest the time of CT-A plus abnormal vital signs preceding imaging were used to calculate SI, Age SI, National Early Warning Score 2 (NEWS2) and Standardised Early Warning Score (SEWS). A consultant gastrointestinal radiologist further reviewed all consultant-reported scans.

RESULTS

In total, 930 patients were admitted with LGIB. Median age was 71 years and 51% were male; 179 (19.2%) patients received red blood cell transfusion and 93 patients (10%) underwent CT-A, who were older and were likely to be hypotensive and receive red cell transfusions. Following exclusions, 92 CT-As were included in the analysis. Nine (9.8%) were positive. Univariate analysis showed no association between positive CT-A and any scoring system. A multivariate analysis, including age and gender, showed association between both NEWS2 and SEWS scores with positive CT-A.

CONCLUSION

In our analysis of the typical LGIB population, CT-A has shown relatively low pick up rate of active bleeding. CT-A clearly has a role in the investigation of LGIB, but selection remains challenging.

A clinical predictive model for risk stratification of patients with severe acute lower gastrointestinal bleeding

BACKGROUND

Lower gastrointestinal bleeding (LGIB) is a common presentation of surgical admissions, imposing a significant burden on healthcare costs and resources. There is a paucity of standardised clinical predictive tools available for the initial assessment and risk stratification of patients with LGIB. We propose a simple clinical scoring model to prognosticate patients at risk of severe LGIB and an algorithm to guide management of such patients.

METHODS

A retrospective cohort study was conducted, identifying consecutive patients admitted to our institution for LGIB over a 1-year period. Baseline demographics, clinical parameters at initial presentation and treatment interventions were recorded. Multivariate logistic regression was performed to identify factors predictive of severe LGIB. A clinical management algorithm was developed to discriminate between patients requiring admission, and to guide endoscopic, angiographic and/or surgical intervention.

RESULTS

226/649 (34.8%) patients had severe LGIB. Six variables were entered into a clinical predictive model for risk stratification of LGIB: Tachycardia (HR ≥ 100), hypotension (SBP < 90 mmHg), anaemia (Hb < 9 g/dL), metabolic acidosis, use of antiplatelet/anticoagulants, and active per-rectal bleeding. The optimum cut-off score of ≥ 1 had a sensitivity of 91.9%, specificity of 39.8%, and positive and negative predictive Values of 45% and 90.2%, respectively, for predicting severe LGIB. The area under curve (AUC) was 0.77.

CONCLUSION

Early diagnosis and management of severe LGIB remains a challenge for the acute care surgeon. The predictive model described comprises objective clinical parameters routinely obtained at initial triage to guide risk stratification, disposition and inpatient management of patients.

Diagnosis and management of acute lower gastrointestinal bleeding: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends that the initial assessment of patients presenting with acute lower gastrointestinal bleeding should include: a history of co-morbidities and medications that promote bleeding; hemodynamic parameters; physical examination (including digital rectal examination); and laboratory markers. A risk score can be used to aid, but should not replace, clinician judgment.Strong recommendation, low quality evidence. 2 : ESGE recommends that, in patients presenting with a self-limited bleed and no adverse clinical features, an Oakland score of ≤ 8 points can be used to guide the clinician decision to discharge the patient for outpatient investigation.Strong recommendation, moderate quality evidence. 3 : ESGE recommends, in hemodynamically stable patients with acute lower gastrointestinal bleeding and no history of cardiovascular disease, a restrictive red blood cell transfusion strategy, with a hemoglobin threshold of ≤ 7 g/dL prompting red blood cell transfusion. A post-transfusion target hemoglobin concentration of 7-9 g/dL is desirable.Strong recommendation, low quality evidence. 4 : ESGE recommends, in hemodynamically stable patients with acute lower gastrointestinal bleeding and a history of acute or chronic cardiovascular disease, a more liberal red blood cell transfusion strategy, with a hemoglobin threshold of ≤ 8 g/dL prompting red blood cell transfusion. A post-transfusion target hemoglobin concentration of ≥ 10 g/dL is desirable.Strong recommendation, low quality evidence. 5: ESGE recommends that, in patients with major acute lower gastrointestinal bleeding, colonoscopy should be performed sometime during their hospital stay because there is no high quality evidence that early colonoscopy influences patient outcomes.Strong recommendation, low quality of evidence. 6 : ESGE recommends that patients with hemodynamic instability and suspected ongoing bleeding undergo computed tomography angiography before endoscopic or radiologic treatment to locate the site of bleeding.Strong recommendation, low quality evidence. 7 : ESGE recommends withholding vitamin K antagonists in patients with major lower gastrointestinal bleeding and correcting their coagulopathy according to the severity of bleeding and their thrombotic risk. In patients with hemodynamic instability, we recommend administering intravenous vitamin K and four-factor prothrombin complex concentrate (PCC), or fresh frozen plasma if PCC is not available.Strong recommendation, low quality evidence. 8 : ESGE recommends temporarily withholding direct oral anticoagulants at presentation in patients with major lower gastrointestinal bleeding.Strong recommendation, low quality evidence. 9: ESGE does not recommend withholding aspirin in patients taking low dose aspirin for secondary cardiovascular prevention. If withheld, low dose aspirin should be resumed, preferably within 5 days or even earlier if hemostasis is achieved or there is no further evidence of bleeding.Strong recommendation, moderate quality evidence. 10: ESGE does not recommend routinely discontinuing dual antiplatelet therapy (low dose aspirin and a P2Y12 receptor antagonist) before cardiology consultation. Continuation of the aspirin is recommended, whereas the P2Y12 receptor antagonist can be continued or temporarily interrupted according to the severity of bleeding and the ischemic risk. If interrupted, the P2Y12 receptor antagonist should be restarted within 5 days, if still indicated.Strong recommendation, low quality evidence.

Extravasation Volume at Computed Tomography Angiography Correlates With Bleeding Rate and Prognosis in Patients With Overt Gastrointestinal Bleeding

OBJECTIVE

Despite the identification of active extravasation on computed tomography angiography (CTA) in patients with overt gastrointestinal bleeding (GIB), a large proportion do not have active bleeding or require hemostatic therapy at endoscopy, catheter angiography, or surgery. The objective of our proof-of-concept study was to improve triage of patients with GIB by correlating extravasation volume of first-pass CTA with bleeding rate and clinical outcomes.

MATERIALS AND METHODS

All patients who presented with overt GIB and active extravasation on CTA from January 2014 to July 2019 were reviewed in this retrospective, institutional review board-approved and Health Insurance Portability and Accountability Act-compliant study. Extravasation volume was assessed using 3-dimensional software and correlated with hemostatic therapy (primary endpoint) and with intraprocedural bleeding, blood transfusions, and mortality as secondary endpoints using logistic regression models (P < 0.0125 indicating statistical significance). Odds ratios were used to determine the effect size of a threshold extravasation volume. Quantitative data (extravasation volume, aorta attenuation, extravasation attenuation and time) were input into a mathematical model to calculate bleeding rate.

RESULTS

Fifty consecutive patients including 6 (12%) upper, 18 (36%) small bowel, and 26 (52%) lower GIB met inclusion criteria. Forty-two underwent catheter angiography, endoscopy, or surgery; 16 had intraprocedural active bleeding, and 24 required hemostatic therapy. Higher extravasation volumes correlated with hemostatic therapy (P = 0.007), intraprocedural active bleeding (P = 0.003), and massive transfusion (P = 0.0001), but not mortality (P = 0.936). Using a threshold volume of 0.80 mL or greater, the odds ratio of hemostatic therapy was 8.1 (95% confidence interval, 2.1-26), active bleeding was 11.8 (2.6-45), and massive transfusion was 18 (2.3-65). With mathematical modeling, extravasation volume had a direct and linear relationship with bleeding rate, and the lowest calculated detectable bleeding rate with CTA was less than 0.1 mL/min.

CONCLUSIONS

Larger extravasation volumes correlate with higher bleeding rates and may identify patients who require hemostatic therapy, have intraprocedural bleeding, and require blood transfusions. Current CTAs can detect bleeding rates less than 0.1 mL/min.

ACR Appropriateness Criteria® Radiologic Management of Lower Gastrointestinal Tract Bleeding: 2021 Update

Diverticulosis remains the commonest cause for acute lower gastrointestinal tract bleeding (GIB). Conservative management is initially sufficient for most patients, followed by elective diagnostic tests. However, if acute lower GIB persists, it can be investigated with colonoscopy, CT angiography (CTA), or red blood cell (RBC) scan. Colonoscopy can identify the site and cause of bleeding and provide effective treatment. CTA is a noninvasive diagnostic tool that is better tolerated by patients, can identify actively bleeding site or a potential bleeding lesion in vast majority of patients. RBC scan can identify intermittent bleeding, and with single-photon emission computed tomography, can more accurately localize it to a small segment of bowel. If patients are hemodynamically unstable, CTA and transcatheter arteriography/embolization can be performed. Colonoscopy can also be considered in these patients if rapid bowel preparation is feasible. Transcatheter arteriography has a low rate of major complications; however, targeted transcatheter embolization is only feasible if extravasation is seen, which is more likely in hemodynamically unstable patients. If bleeding site has been previously localized but the intervention by colonoscopy and transcatheter embolization have failed to achieve hemostasis, surgery may be required. Among patients with obscure (nonlocalized) recurrent bleeding, capsule endoscopy and CT enterography can be considered to identify culprit mucosal lesion(s). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Clinical factors associated with successful embolization of lower gastrointestinal bleeding

AIM

To develop a model of clinical factors that may predict: (1) technically and clinically successful embolization of a bleeding vessel at digital subtraction angiography (DSA) for lower gastrointestinal bleed (LGIB); (2) a negative DSA in the presence of positive CT-mesenteric angiography (CTMA) for LGIB.

METHODS

A retrospective cohort study of all DSAs conducted with intent for embolization for acute LGIB over a 10-year period was undertaken. Pre-procedural and intra-procedural clinical variables were evaluated using uni- and multi-variate analysis.

RESULTS

One hundred and twenty-three DSAs were evaluated. Technical success was 81% and clinical success 78% where DSA was positive. Technical success was associated with super-selective approach, contrast extravasation on CT, haemoglobin drop, anatomical source and time from CT to DSA on univariate analysis. On multivariate analysis, time from CT to DSA was significant with a higher success probability within 120 min with different factors being salient depending on degree of delay. Clinical success was only associated with activated partial thromboplastin time (<27.5 s). A negative DSA was associated with anatomical source, haemodynamic stability, platelet count and time from CT to DSA on univariate analysis. The latter three remained so on multivariate analysis.

CONCLUSION

A triaging approach to utilizing emergency DSA may be helpful. If prolonged delay between CT and DSA is anticipated, with haemodynamic stability and a near-normal platelet count, the DSA may not be fruitful. Technical success may be more likely if DSA occurs within 120 min. Clinical success may be more likely if activated partial thromboplastin time is within normal range.

Effectiveness of endoscopic hemostasis in preventing diverticular bleeding with extravasation detected by contrast-enhanced computed tomography: A single-center retrospective cohort study

In diverticular bleeding, extravasation detected by computed tomography indicates active bleeding. It is unclear whether an endoscopic procedure is the best method of hemostasis for diverticular bleeding. This retrospective study was conducted to examine the effectiveness of endoscopic hemostasis in preventing diverticular rebleeding with extravasation visualized by contrast-enhanced computed tomography.This single-center, retrospective, the observational study utilized data from an endoscopic database. Adult patients admitted to our hospital due to diverticular bleeding diagnosed by colonoscopy were included. We compared the data between the extravasation-positive and extravasation-negative groups. The primary outcome was the proportion of successful hemostasis without rebleeding within 1 month after the first endoscopic procedure. Altogether, 69 patients were included in the study (n = 17, extravasation-positive group; n = 52, extravasation-negative group). The overall rebleeding rate was 30.4% (21/69). The rebleeding rate was higher in the extravasation-positive group than in the extravasation-negative group, although without a statistically significant difference. However, among the patients who underwent endoscopic hemostasis, the rebleeding rate was significantly higher in the extravasation-positive group than in the extravasation-negative group (50% [8/16] vs 10.5% [2/19], p = .022). In the extravasation-positive group, all 8 patients with rebleeding underwent repeat colonoscopy. Of these, 5 patients required additional clips; bleeding was controlled in 3 patients, while arterial embolization or surgery was required for hemostasis in 2 patients. None of the remaining 3 patients with rebleeding in the extravasation-positive group required clipping; thus, their conditions were only observed.Many patients with diverticular bleeding who exhibited extravasation on computed tomography experienced rebleeding after endoscopic hemostasis. However, bleeding in more than half of these patients could be stopped by 2 endoscopic procedures, without performing transcatheter arterial embolization or surgery even if rebleeding occurred. Some serious major complications due to such invasive interventions are reported in the literature, but colonoscopic complications did not occur in our patients. Endoscopic hemostasis may be the preferred and effective first-line therapy for patients with diverticular bleeding who have extravasation, as visualized by contrast-enhanced computed tomography.

Empiric cone-beam CT-guided embolization in acute lower gastrointestinal bleeding

OBJECTIVES

To evaluate the clinical effect and safety of cone-beam CT (CBCT)-guided empirical embolization for acute lower gastrointestinal bleeding (LGIB) in patients with a positive CT angiography (CTA) but subsequent negative digital subtraction angiography (DSA).

METHODS

A retrospective study of consecutive LGIB patients with a positive CTA who received a DSA within 24 h from January 2008 to July 2019. Patients with a positive DSA were treated with targeted embolization (TE group). Patients with a negative DSA underwent an empiric CBCT-guided embolization of the assumed ruptured vas rectum (EE group) or no embolization (NE group). Recurrent bleeding, major ischemic complications, and in-hospital mortality were compared by means of Fisher's exact test. Further subgroup analysis was performed on hemodynamic instability.

RESULTS

Eighty-five patients (67.6 years ± 15.7, 52 men) were included (TE group, n = 47; EE group, n = 19; NE group, n = 19). If DSA was positive, technical success of targeted embolization was 100% (47/47). If DSA was negative and the intention to treat by empiric CBCT-guided embolization, technical success was 100% (19/19). Recurrent bleeding rates in the TE group, EE group, and NE group were 17.0% (8/47), 21.1% (4/19), and 52.6% (10/19) respectively. Empiric CBCT-guided embolization reduced rebleeding significantly in patients with a negative DSA and hemodynamic instability (EE group, 3/10 vs NE group, 10/12, p = .027). Major ischemic complications occurred in one patient (TE group). Overall, the in-hospital mortality rate was 7.1% (6/85).

CONCLUSION

Empiric cone-beam CT-guided embolization proved to be a feasible, effective, and safe treatment strategy to reduce rebleeding and improve clinical success in hemodynamically unstable patients with acute LGIB, positive CTA but negative DSA.

KEY POINTS

• A novel transarterial embolization technique guided by cone-beam CT could be developed extending the "empiric" embolization strategy to lower gastrointestinal bleeding. • By implementing the empiric treatment strategy, nearly all patients with an active lower gastrointestinal bleeding on CTA will be eligible for a superselective empiric embolization, even if subsequent catheter angiography is negative. • In patients with a negative catheter angiography, empiric embolization reduces the rebleeding rate and, particularly in hemodynamically unstable patients, improves clinical success compared with a conservative "wait-and-see" management.

Angiography versus colonoscopy in patients with severe lower gastrointestinal bleeding: a nation-wide observational study

Aim

Clinical guidelines for acute lower gastrointestinal bleeding (LGIB) recommend non‐endoscopic treatment when endoscopic treatment is difficult or the patient is hemodynamically unstable. The aim of this study was to investigate whether angiography should be prioritized as initial treatment for severe LGIB patients over colonoscopy.

Methods

We undertook a retrospective cohort study using the Japanese Diagnosis Procedure Combination inpatient database. We compared adult patients who underwent colonoscopy or angiography within 1 day of admission for severe LGIB from 2010 to 2017. The primary outcome was in‐hospital mortality. Secondary outcomes included surgery carried out within 1 day after admission and surgery carried out between 2 and 7 days of admission. Propensity score‐matched analyses were undertaken to adjust for confounders.

Results

We identified 6,546 eligible patients. The patients were divided into the colonoscopy group (n = 5,737) and angiography group (n = 809). After one‐to‐four propensity score matching, we compared 3,220 and 805 patients who underwent colonoscopy and angiography, respectively. The angiography group was not significantly associated with reduced in‐hospital mortality compared with the colonoscopy group. In contrast, the number of patients who underwent surgery within 1 day of admission was significantly lower in the angiography group than in the colonoscopy group.

Conclusions

The present study revealed that in‐hospital mortality did not significantly differ between colonoscopy and angiography, even in severe LGIB patients. Although this study was unable to identify which subgroups should undergo angiography for primary hemostasis, angiography might be a better option than colonoscopy for initial hemostasis in more severe cases of LGIB.

Localization and Definitive Control of Lower Gastrointestinal Bleeding with Angiography and Embolization

Angiography has long been a mainstay of lower gastrointestinal bleeding localization. More recently, angioembolism has been used therapeutically for bleeding control, but there are limited data on its efficacy. This study was designed to evaluate the efficacy of angiography and embolization for localizing and treating lower gastrointestinal bleeding as well evaluate the occurrence of bowel ischemia after embolization. This study is a retrospective descriptive review of all patients undergoing mesenteric angiography at a tertiary hospital over an eight-year period. Clinical data were recorded including patient demographics, causes of bleeding, procedures, and outcomes. Patients were excluded if the cause of bleeding was upper gastrointestinal bleeding or the medical record was missing data. Localization and definitive control of bleeding was the primary end point. One hundred fifty-nine angiograms were performed on 152 patients. Mean age was 72 years. Angiographic localization was successful in 23.7 per cent of patients. Although embolization after angiographic localization achieved definitive control of bleeding in 50 per cent of patients, the success rate was only 8.6 per cent of all patients who had angiography. One patient developed postembolization ischemia requiring laparotomy. Angiographic localization of lower gastrointestinal bleeding is successful in only 23.7 per cent of patients. Definitive hemostasis through embolization was successful in only 8.6 per cent of patients who underwent angiography for lower gastrointestinal bleeding.

Trauma CT evaluation prior to selective angiography in patients with traumatic injuries: negative predictive power and factors affecting its utility

PURPOSE

To evaluate the predictive power of arterial injury detected on contrast-enhanced CT (trauma CT (tCT)) imaging obtained prior to selective angiography for treatment of patients with traumatic abdominal and pelvic injuries.

MATERIALS AND METHODS

A retrospective chart review was performed of all patients who underwent angiography after undergoing contrast-enhanced CT imaging for the evaluation/treatment of traumatic injuries to the abdomen and pelvis between March 2014 and September 2018. Data collection included demographics, pertinent history and physical findings, CT and angiography findings, treatment information, and outcomes.

RESULTS

Eighty-nine (63 males, mean age = 45.8 ± 20.5 years) patients that were found to have 102 traumatic injuries on tCT and subsequently underwent angiography met inclusion criteria for this study. Sixty-four injuries demonstrated evidence of traumatic vascular injury on initial tCT. A negative tCT was able to predict subsequent negative angiography in 83% of cases (negative predictive power = 83%). The ability of tCT to rule out a positive finding on subsequent angiography was also 83% (sensitivity = 83%). The average systolic blood pressure and hemoglobin concentration at the time of tCT were higher in patients who had positive tCT than in patients with negative tCT (p < 0.05 and p < 0.01, respectively). The average time to angiography was greater in patients whom had subsequent negative angiography than the patients who had subsequent positive angiography (p < 0.05).

CONCLUSION

Contrast-enhanced CT imaging may be able to help stratify patients who may have subsequent negative angiograms. Hemodynamic factors may affect sensitivity of tCT. Shorter time to angiography may increase the chance of identifying the injury on subsequent angiography.

Diagnosis and Management of Non-Variceal Gastrointestinal Hemorrhage: A Review of Current Guidelines and Future Perspectives

Non-variceal gastrointestinal bleeding (GIB) is a significant cause of mortality and morbidity worldwide which is encountered in the ambulatory and hospital settings. Hemorrhage form the gastrointestinal (GI) tract is categorized as upper GIB, small bowel bleeding (also formerly referred to as obscure GIB) or lower GIB. Although the etiologies of GIB are variable, a strong, consistent risk factor is use of non-steroidal anti-inflammatory drugs. Advances in the endoscopic diagnosis and treatment of GIB have led to improved outcomes. We present an updated review of the current practices regarding the diagnosis and management of non-variceal GIB, and possible future directions.

Analysis of time delay between computed tomography and digital subtraction angiography on the technical success of interventional embolisation for treatment of lower gastrointestinal bleeding

INTRODUCTION

A retrospective study was undertaken to determine a potential relationship, based on the time delay, between a positive lower gastrointestinal bleed demonstrated on computed tomography (CT) and a positive digital subtraction angiographic (DSA) study and the impact on technical success.

METHODS

This study investigated the correlation of time delays between imaging modalities and technical success with endovascular embolisation procedures over a 10-year period.

RESULTS

A total of 110 patient events were analysed, and it was observed that the greater the time delay between modalities (up to 7 h), the weaker the correlation between a bleed observed on CT and DSA. This was also reflected by the technical success of the embolisation treatment. Patients experienced shorter delays when the event occurred out of normal business hours, however with decreased rates of technical success.

CONCLUSIONS

There is a suggestion patients should be escalated to the angiography suite for DSA imaging as soon as possible to maximise the ability to angiographically observe acute bleeding and treat appropriately with interventional embolisation. More research in this area is required to statistically confirm this.

Diagnosis and therapeutic strategies for small bowel vascular lesions

Small bowel vascular lesions, including angioectasia (AE), Dieulafoy’s lesion (DL) and arteriovenous malformation (AVM), are the most common causes of obscure gastrointestinal bleeding. Since AE are considered to be venous lesions, they usually manifest as a chronic, well-compensated condition. Subsequent to video capsule endoscopy, deep enteroscopy can be applied to control active bleeding or to improve anemia necessitating blood transfusion. Despite the initial treatment efficacy of argon plasma coagulation (APC), many patients experience re-bleeding, probably because of recurrent or missed AEs. Pharmacological treatments can be considered for patients who have not responded well to other types of treatment or in whom endoscopy is contraindicated. Meanwhile, a conservative approach with iron supplementation remains an option for patients with mild anemia. DL and AVM are considered to be arterial lesions; therefore, these lesions frequently cause acute life-threatening hemorrhage. Mechanical hemostasis using endoclips is recommended to treat DLs, considering the high re-bleeding rate after primary APC cauterization. Meanwhile, most small bowel AVMs are large and susceptible to re-bleeding therefore, they usually require surgical resection. To achieve optimal diagnostic and therapeutic approaches for each type of small bowel lesion, the differences in their epidemiology, pathology and clinical presentation must be understood.

Diagnosis and management of acute lower gastrointestinal bleeding: guidelines from the British Society of Gastroenterology

This is the first UK national guideline to concentrate on acute lower gastrointestinal bleeding (LGIB) and has been commissioned by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG). The Guidelines Development Group consisted of representatives from the BSG Endoscopy Committee, the Association of Coloproctology of Great Britain and Ireland, the British Society of Interventional Radiology, the Royal College of Radiologists, NHS Blood and Transplant and a patient representative. A systematic search of the literature was undertaken and the quality of evidence and grading of recommendations appraised according to the GRADE(Grading of Recommendations Assessment, Development and Evaluation) methodology. These guidelines focus on the diagnosis and management of acute LGIB in adults, including methods of risk assessment and interventions to diagnose and treat bleeding (colonoscopy, computed tomography, mesenteric angiography, endoscopic therapy, embolisation and surgery). Recommendations are included on the management of patients who develop LGIB while receiving anticoagulants (including direct oral anticoagulants) or antiplatelet drugs. The appropriate use of blood transfusion is also discussed, including haemoglobin triggers and targets.

The Clinician's Guide to Suspected Small Bowel Bleeding

Small bowel bleeding accounts for 5-10% of gastrointestinal bleeding. With the advent of capsule endoscopy, device-assisted enteroscopy, and multiphase CT scanning, a small bowel source can now be found in many instances of what has previously been described as obscure gastrointestinal bleeding. We present a practical review on the evaluation and management of small bowel bleeding for the practicing clinician.

Predicting the need for transfer and interventional angiography for patients with acute colonic haemorrhage in a regional setting

BACKGROUND

Radiological angioembolization is an important strategy in management of acute colonic bleeding. Due to requirement for specialized interventional radiology, many hospitals rely on transfer for this service. This study aimed to identify patient and clinical factors associated with positive (blush) computed tomography mesenteric angiogram (CTMA) or need for invasive angiography. The secondary aim was to identify a patient population who may forego transfer and be safely managed in a regional centre.

METHODS

All presentations to Central Coast Local Health District with colonic bleeding from June 2013-June 2017 were included. A guideline for transfer of patients with positive CTMA from Central Coast Local Health District to Royal North Shore Hospital had been established prior to the study period. Demographics, medical background, transfusion requirement, presentation details and mortality data were collected on all patients.

RESULTS

Of 2378 patients presenting with colonic bleeding, 71 of 247 patients investigated with CTMA had a blush. Forty-six patients were transferred to Royal North Shore Hospital. Of these, 28 proceeded to interventional angiography with 19 undergoing angioembolization. Acute transfusion ≥5 units (odds ratio 6.78, P < 0.01) was the only significant predictor of needing interventional angiography. There was no association between age, bleeding site (right or left), use of antiplatelet or anticoagulation, diverticular disease or chronic kidney disease and identification of arterial bleeding on interventional angiography. There was no mortality or significant procedure-related morbidity.

CONCLUSION

A patient's medical background demonstrates a lack of correlation to identification of active bleeding on interventional angiography. Patients requiring ≥5 units blood transfusion should be considered for transfer and interventional angiography.

Diagnostic and therapeutic considerations for obscure gastrointestinal bleeding in patients with chronic kidney disease

Recurrent obscure gastrointestinal bleeding amongst patients with chronic kidney disease is a challenging problem gastroenterologists are facing and is associated with an extensive diagnostic workup, limited therapeutic options, and high healthcare costs. Small-bowel angiodysplasia is the most common etiology of obscure and recurrent gastrointestinal bleeding in the general population. Chronic kidney disease is associated with a higher risk of gastrointestinal bleeding and of developing angiodysplasia compared with the general population. As a result, recurrent bleeding in this subgroup of patients is more prevalent and is associated with an increased number of endoscopic and radiographic procedures with uncertain benefit. Alternative medical therapies can reduce re-bleeding; however, more studies are needed to confirm their efficacy in this subgroup of patients.

Transcatheter arterial embolisation for acute lower gastrointestinal haemorrhage: a single-centre study

OBJECTIVE

To investigate the safety and efficacy of transcatheter arterial embolisation (TAE) in the management of lower gastrointestinal bleeding (LGIB) and to identify predictors of clinical outcomes.

METHODS

Between December 2005 and April 2017, 274 patients underwent diagnostic angiography for signs and symptoms of LGIB; 134 patients with positive angiographic findings were retrospectively analysed. The technical success of TAE and clinical outcomes, including recurrent bleeding, major complications, and in-hospital mortality were evaluated. The associations of various clinical and technical factors with clinical outcomes were analysed. Predictors for clinical outcomes were evaluated using univariate and multivariate logistic regression analyses.

RESULTS

A total of 134 patients (mean age, 59.7 years; range, 14-82 years) underwent TAE for LGIB. The bleeding foci were in the small bowel in 74 patients (55.2%), colon in 35 (26.1%), and rectum in 25 (18.7%). Technical success was achieved in 127 patients (94.8%). The clinical success rate was 63% (80/127). The rates of recurrent bleeding, major complications, and in-hospital mortality were 27.9% (31/111), 18.5% (23/124), and 23.6% (33/127), respectively. Superselective embolisation and the use of N-butyl cyanoacrylate (NBCA) were significant prognostic factors associated with reduced recurrent bleeding (OR, 0.258; p = 0.004 for superselective embolisation, OR, 0.313; p = 0.01 for NBCA) and fewer major complications (OR, 0.087; p ˂ 0.001 for superselective embolisation, OR, 0.272; p = 0.007 for NBCA).

CONCLUSIONS

TAE is an effective treatment modality for LGIB. Superselective embolisation is essential to reduce recurrent bleeding and avoid major complications. NBCA appears to be a preferred embolic agent.

KEY POINTS

• Transcatheter arterial Embolisation (TAE) is a safe and effective treatment for lower gastrointestinal tract haemorrhage. • Superselective embolisation is essential to improve outcomes. • N-butyl cyanoacrylate (NBCA) appears to be a preferred embolic agent with better clinical outcomes.

Small bowel bleeding: cause and the role of endoscopy and medical therapy

PURPOSE OF REVIEW

The objective is to provide an overview on the cause of small bowel bleeding. We discuss the role of small bowel endoscopy in the management of small bowel bleeding and provide an outline of pharmacotherapy that can be additionally beneficial.

RECENT FINDINGS

Small bowel capsule endoscopy (SBCE) is the initial diagnostic investigation of choice in small bowel bleeding. Computed tomography (CT) can be helpful in the context of small bowel tumours. Device-assisted enteroscopy (DAE) enables several therapeutic procedures such as argon plasma coagulation (APC) and haemoclip application. It can also guide further management with histology or by marking culprit lesions with India ink. A persistent rate of rebleeding despite APC is increasingly being reported. Pharmacotherapy has an emerging role in the management of small bowel bleeding. Somatostatin analogues are a well tolerated class of drugs that can play an additional role in the management of refractory bleeding secondary to small bowel angioectasias.

SUMMARY

SBCE is useful in determining the cause of small bowel bleeding. DAE offers an endoscopic therapeutic approach to small bowel bleeding replacing surgery and intraoperative enteroscopy. Pharmacotherapy, in addition to endotherapy, can play an important role in the management of multifocal, recurring bleeding small bowel lesions.

Predictors of Active Extravasation and Complications after Conventional Angiography for Acute Intraabdominal Bleeding

Conventional angiography is used to evaluate and treat possible sources of intraabdominal bleeding, though it may cause complications such as contrast-induced nephropathy (CIN). The study’s purpose was to identify factors predicting active extravasation and complications during angiography for acute intraabdominal bleeding. All conventional angiograms for acute bleeding (January 2013–June 2015) were reviewed retrospectively, including 75 angiograms for intraabdominal bleeding in 70 patients. Demographics, comorbidities, vital signs, complications within one month, and change in hematocrit (ΔHct) and fluids and blood products administered over the 24 h prior to angiography were recorded. Of 75 exams, 20 (27%) demonstrated extravasation. ΔHct was the only independent predictor of extravasation (p = 0.017), with larger ΔHct (−17%) in patients with versus those without extravasation (–1%) (p = 0.01). CIN was the most common complication, occurring in 10 of 66 angiograms (15%). Glomerular filtration rate (GFR) was the only independent predictor (p = 0.03); 67% of patients with GFR < 30, 29% of patients with GFR 30–60, and 8% of patients with GFR > 60 developed CIN. For patients with intraabdominal bleeding, greater ΔHct decrease over 24 h before angiography predicts active extravasation. Pre-existing renal impairment predicts CIN. Patients with large hematocrit declines should be triaged for rapid angiography, though benefits can be weighed with the risk of renal impairment.

The use of super-selective mesenteric embolisation as a first-line management of acute lower gastrointestinal bleeding

Introduction

In this study, we aim to assess the efficacy and safety of digital subtraction angiography (DSA) and super-selective mesenteric artery embolisation in managing lower gastrointestinal bleeding (LGIB) at a multi-centre health service in Melbourne (Australia).

Method

A retrospective case series of patients with LGIB treated with superselective embolisation in our area health service. Patients with confirmed active LGIB, on either radionuclide scintigraphy (RS) or contrast-enhanced multi-detector CT angiography (CE-MDCT), were referred for DSA, and subsequently endovascular intervention. Data collected included patient characteristics; screening modality; bleeding territory; embolisation technique; technical and clinical success; short to mediumterm complications and mortality up to 30 days; and the need for surgery related to procedural failure or complications.

Results

There were 55 hospital admissions with acute unstable lower gastrointestinal bleeding that were demonstrable on CE-MDCT or RS over a 30-month period (from 1 January 2014 to 30 June 2016). Of these, eighteen patients were embolised. Immediate haemostasis was achieved in all embolised cases. Eight patients (44%) had clinical re-bleeding postembolisation and warranted repeated imaging. However, only one case (5.6%) had active bleeding identified and was re-embolised. There was no documented case of bowel ischemia or ischemic-stricture and none progressed on to surgery. 30 day mortality was zero.

Conclusion

Super-selective mesenteric embolisation is a viable, safe and effective first line management for localised LGIB. Our results overall compare favourably with the published experiences of other institutions. It is now accepted first-line practice at our institution to manage localised LGIB with embolisation.

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A study into the efficacy of mesenteric embolisation in managing acute lower GI bleeding.

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Mesenteric embolisation is an effective management for localised acute lower GI bleeding.

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Our results compare favourably with published experiences of other institutions.

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It is first-line practice at our institution to embolise localised acute lower GI bleeds.

Detection of suspected small bowel bleeding: challenges and controversies

Detection of small bowel (SB) bleeding remains a challenge to gastroenterologists, with a dearth of standardized recommendations regarding evaluation and management. Areas covered: A recursive literature search was performed using PubMed, Cochrane and Medline databases for original and review articles on SB and obscure gastrointestinal bleeding (OGIB). Based upon the available literature, this review outlines the main challenges and controversies, and provides a practical and cost-effective approach towards SB bleeding. Expert commentary: SB bleeding is suspected in patients with persistent or recurrent bleeding after negative bidirectional endoscopy, and unexplained iron deficiency anemia. Selection of test(s) should be individualized based upon patient presentation and suspicion for type of underlying lesion. Endoscopic or radiologic evaluation and treatment is the mainstay in the majority of patients, while pharmacologic agents may have a role in patients with refractory bleeding, and those unable to undergo evaluation.

ACG Clinical Guideline: Diagnosis and Management of Small Bowel Bleeding

Bleeding from the small intestine remains a relatively uncommon event, accounting for ~5-10% of all patients presenting with gastrointestinal (GI) bleeding. Given advances in small bowel imaging with video capsule endoscopy (VCE), deep enteroscopy, and radiographic imaging, the cause of bleeding in the small bowel can now be identified in most patients. The term small bowel bleeding is therefore proposed as a replacement for the previous classification of obscure GI bleeding (OGIB). We recommend that the term OGIB should be reserved for patients in whom a source of bleeding cannot be identified anywhere in the GI tract. A source of small bowel bleeding should be considered in patients with GI bleeding after performance of a normal upper and lower endoscopic examination. Second-look examinations using upper endoscopy, push enteroscopy, and/or colonoscopy can be performed if indicated before small bowel evaluation. VCE should be considered a first-line procedure for small bowel investigation. Any method of deep enteroscopy can be used when endoscopic evaluation and therapy are required. VCE should be performed before deep enteroscopy if there is no contraindication. Computed tomographic enterography should be performed in patients with suspected obstruction before VCE or after negative VCE examinations. When there is acute overt hemorrhage in the unstable patient, angiography should be performed emergently. In patients with occult hemorrhage or stable patients with active overt bleeding, multiphasic computed tomography should be performed after VCE or CTE to identify the source of bleeding and to guide further management. If a source of bleeding is identified in the small bowel that is associated with significant ongoing anemia and/or active bleeding, the patient should be managed with endoscopic therapy. Conservative management is recommended for patients without a source found after small bowel investigation, whereas repeat diagnostic investigations are recommended for patients with initial negative small bowel evaluations and ongoing overt or occult bleeding.

What if endoscopic hemostasis fails? Alternative treatment strategies: interventional radiology

Since the 1960s, interventional radiology has played a role in the management of gastrointestinal bleeding. What began primarily as a diagnostic modality has evolved into much more of a therapeutic tool. And although the frequency of gastrointestinal bleeding has diminished thanks to management by pharmacologic and endoscopic methods, the need for additional invasive interventions still exists. Transcatheter angiography and intervention is a fundamental step in the algorithm for the treatment of gastrointestinal bleeding.

The American Society for Gastrointestinal Endoscopy (ASGE) diagnostic algorithm for obscure gastrointestinal bleeding: eight burning questions from everyday clinical practice

The diagnosis and management of patients with obscure gastrointestinal bleeding are often long and challenging processes. Over the last 10 years the introduction in clinical practice of new diagnostic and therapeutic procedures (i.e. Capsule Endoscopy, Computed Tomographic Enterography, Magnetic Resonance Enterography, and Device Assisted Enteroscopy) has revolutionized the diagnostic/therapeutic work-up of these patients. Based on evidence published in the last 10 years, international scientific societies have proposed new practice guidelines for the management of obscure gastrointestinal bleeding, which include these techniques. However, although these algorithms (the most recent ones are endorsed by the American Society for Gastrointestinal Endoscopy - ASGE) allow the management of the large majority of patients, some issues still remain unsolved. The present paper reports the results of the discussion, based on the literature published up to September 2011, among a panel of experts and gastroenterologists, working with Capsule Endoscopy and with Device Assisted Enteroscopy, attending the 6th annual meeting of the Italian Club for Capsule Endoscopy and Enteroscopy. Eight unresolved issues were selected: each of them is presented as a "Burning question" and the "Answer" is the strategy proposed to manage it, according to both the available evidence and the discussion among participants.

Mesenteric angiography for acute gastrointestinal bleed: predictors of active extravasation and outcomes

BACKGROUND

Ongoing gastrointestinal bleeding (GIB) following endoscopic therapy and deciding between mesenteric angiography and surgery often challenge surgeons. We sought to identify predictors of positive angiographic study (active contrast medium extravasation) and characterize outcomes of embolization for acute GIB.

METHODS

We retrospectively analyzed angiographies for GIB at 2 teaching hospitals from January 2005 to December 2008. The χ2, Wilcoxon rank sum and t tests determined significance. A Cox proportional hazards model was used for multivariate analyses.

RESULTS

Eighteen of 83 (22%) patients had active extravasation on initial angiography and 25 (30%) were embolized. Patients with active extravasation had more packed red blood cell (PRBC; 5.3 v. 2.8 units, p < 0.001) and fresh frozen plasma (4.8 v. 1.7 units, p = 0.005) transfusions 24 hours preangiography and were more likely to be hemodynamically unstable at the time of the procedure (67% v. 28%, p = 0.001) than patients without active extravasation. Each unit of PRBC transfused increased the risk of a positive study by 30% (hazard ratio [HR] 1.3, 95% confidence interval [CI] 1.2-1.6 per unit). Embolization did not decrease recurrent bleeding (53% v. 52%) or length of stay in hospital (28.1 v. 27.5 d, p = 0.95), but was associated with a trend toward fewer emergency surgical interventions (13% v. 26%, p = 0.31) and greater 30-day mortality (33% v. 7%, p = 0.006) than nonembolization. Blind embolization was performed in 10 of 83 (12%) patients and was found to be an independent predictor of death in patients without active extravasation (HR 9.2, 95% CI 1.5-55.9).

CONCLUSION

The number of PRBC units transfused correlates with greater likelihood of a positive study. There was a significant increase in mortality in patients who underwent angioembolization. Large prospective studies are needed to further characterize the indications for angiography and blind embolization.

Mesenteric embolization for lower gastrointestinal bleeding

PURPOSE

Mesenteric embolization is an established treatment for lower gastrointestinal bleeding. The aim of this study was to determine the outcome of angiography and embolization and its influencing factors.

METHODS

A prospective database of all mesenteric angiograms performed for lower gastrointestinal bleeding at a tertiary center between 1998 and 2008 was analyzed in combination with chart review.

RESULTS

There were 107 angiograms performed during 83 episodes of lower gastrointestinal bleeding in 78 patients. Active bleeding was identified in 40 episodes (48%), and embolizations were performed in 37 (45%). One patient without active bleeding on angiogram also underwent embolization, making a total of 38 embolizations. Overall mortality was 7% with 4 deaths due to rebleeding and 2 deaths due to a medical comorbidity (respiratory failure, pneumonia). Short-term complications of angiography were false aneurysm (1 patient) and Enterobacter sepsis (1 patient). Long-term complications were groin lymphocele (1 patient) and late rebleed from collateralization (1 patient). In 43 episodes, angiography did not demonstrate active bleeding. Twelve (28%) of these patients continued to bleed, 9 of whom had successful surgery. Of the 38 patients who had embolizations, all had immediate cessation of bleeding. Nine patients (24%) later rebled; 5 of these patients required surgery and 3 had reembolizations. Of the 3 patients who underwent reembolization, 2 developed ischemic bowel and 1 stopped bleeding; surgery was required in 1 patient.

CONCLUSIONS

Mesenteric angiography for lower gastrointestinal bleeding effectively identifies the site of bleeding in 48% of patients and allows embolization in 45%. Embolization achieves clinical success in 76% of patients but repeat embolization is associated with a high rate of complications.

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.

Angiographically negative acute arterial upper and lower gastrointestinal bleeding: incidence, predictive factors, and clinical outcomes

OBJECTIVE

To evaluate the incidence, predictive factors, and clinical outcomes of angiographically negative acute arterial upper and lower gastrointestinal (GI) bleeding.

MATERIALS AND METHODS

From 2001 to 2008, 143 consecutive patients who underwent an angiography for acute arterial upper or lower GI bleeding were examined.

RESULTS

The angiographies revealed a negative bleeding focus in 75 of 143 (52%) patients. The incidence of an angiographically negative outcome was significantly higher in patients with a stable hemodynamic status (p < 0.001), or in patients with lower GI bleeding (p = 0.032). A follow-up of the 75 patients (range: 0-72 months, mean: 8 +/- 14 months) revealed that 60 of the 75 (80%) patients with a negative bleeding focus underwent conservative management only, and acute bleeding was controlled without rebleeding. Three of the 75 (4%) patients underwent exploratory surgery due to prolonged bleeding; however, no bleeding focus was detected. Rebleeding occurred in 12 of 75 (16%) patients. Of these, six patients experienced massive rebleeding and died of disseminated intravascular coagulation within four to nine hours after the rebleeding episode. Four of the 16 patients underwent a repeat angiography and the two remaining patients underwent a surgical intervention to control the bleeding.

CONCLUSION

Angiographically negative results are relatively common in patients with acute GI bleeding, especially in patients with a stable hemodynamic status or lower GI bleeding. Most patients with a negative bleeding focus have experienced spontaneous resolution of their condition.

Accurate localization of life threatening colonic hemorrhage during nuclear medicine bleeding scan as an aid to selective angiography

Purpose

To describe a new technique to help localize life threatening colorectal bleeding during nuclear medicine bleeding scan to aid in selective angiography.

Methods

During the gastrointestinal bleeding scan, a simple metallic marker (paper clip) was used to localize the bleeding site on the patient body. Angiography was then performed within 2 hours. The marker was then used to guide superselective angiography and embolization.

Results

5 cases of patients with colorectal bleeding were performed using this technique with cessation of bleeding in 4/5 initial attempts. 1 patient required a repeat angiogram that did demonstrate the bleeding on the second attempt allowing superselective angiography and embolization that resulted in cessation of bleeding. This patient with a rectal bleed required selection of additional vessels guided by the marker on the second attempt.

Conclusion

The dilemma of positive scintigraphic evidence of colonic bleeding with negative arteriography can be resolved with the use of a metal marker during the scintigram to guide superselective angiography. Although in our small series of patients this technique appears to be simple and effective, further clinical investigation is warranted with a larger patient population. This technique may offer a role in therapy in coordination with the colorectal surgeon for the high risk patient in an otherwise life threatening situation.

Angiography and transcatheter embolizaion for acute lower gastrointestinal hemorrhage: clinical value and influencing factors of diagnosis and treatment

AIM: To evaluate the clinical value of angiography and transcatheter embotherapy in patients with acute massive lower gastrointestinal (GI) hemorrhage, and to analyze the influencing factors.

METHODS: We retrospectively analyzed data of 39 cases with acute massive arterial hemorrhage of lower gastrointestinal tract, including such data as transfusion amount, blood pressure and hemoglobin (Hb) before and after embolization. Baseline, procedural, and outcome parameters were recorded in accordance with current Society of Interventional Radiology guidelines. Follow-up time was three to six months. Outcomes included technical success (Immediate disappearance of bleeding signs or obstruction of leaking-blood artery after embotherapy), clinical success (without rebleeding within 30 days), delayed rebleeding (more than 30 days), and major or minor complication rates.

RESULTS: Twenty-six patients of the 39 with acute massive lower GI hemorrhage received blood transfusion before embolization, and only 4 patents with HB below 40 g/L before embolization, received the transfusion post-embolization. The positive diagnostic rates of lower GI hemorrhage of angiograms were 31% with catheter-tips located at 2^nd-grade-blood vessels (superior mesenteric arteries, inferior mesenteric arteries), and 69% at 3^rd-grade-blood vessels (jejunal artery, iliac artery, iliac-cecal artery, cecal artery, and marginal artery), respectively. The total positive diagnostic rate of angiography about lower GI bleeding reached 100%. Embolization was performed with injection of gelatin sponge particles or thin strips via catheter following angiogram with angiographical catheter (5French size) or with microcatheter (3French size). Immediate cessation bleeding post-embolization was 92%. The technical success rates and clinical success rates reached 100% and 89.7%, respectively. Transient epigastric pains occurred to 4 patients because of superior mesenteric artery spasm, 2 cases were managed with medications, and the others were relieved spontaneously. Three days after transcatheter embolization, endoscopy examination of four patients showed the areas of mucosal erythema, swelling and pallor. None of major complications was found such as necrosis or serious ischemia of lower GI.

CONCLUSION: Angiography and transcatheter embolization are effective and safe methods to locate the bleeding spot and stop bleeding immediately, which can be considered as alternatives to diagnosis and treatment of acute massive lower GI hemorrhage. The positive-bleeding-diagnostic rates of angiograms in lower GI hemorrhage and the efficacy of embolization are influenced by varied factors.

Radiographic work-up and treatment of lower gastrointestinal bleeding

Lower gastrointestinal hemorrhage is a common reason for hospital admission. Spontaneous cessation occurs in the majority of these patients; however, continued major bleeding is a difficult clinical problem. Emergency surgery, without prior knowledge of the bleeding site is associated with high morbidity and mortality rates. Accurate localization is therefore desirable. The authors present a review of current radiological imaging modalities and therapeutic options available to the clinician. They also provide a management algorithm to aid in the strategic management of this group of patients.

ACR Appropriateness Criteria on treatment of acute nonvariceal gastrointestinal tract bleeding

Acute upper gastrointestinal (UGI) tract bleeding is best initially investigated and treated with endoscopy. For patients who fail therapeutic endoscopy, both surgery and transcatheter arteriography and intervention (TAI) are equally effective. Transcatheter arteriography and intervention should be considered as a treatment option in patients with UGI bleeding, particularly those at high risk for surgery. Transcatheter arteriography and intervention for UGI bleeding has a low rate of major complications, and prolonged clinical success is seen in at least 65% of patients. Transcatheter arteriography and intervention is the best method of treatment for bleeding occurring into the biliary tree or pancreatic duct. In patients with acute lower gastrointestinal (LGI) tract bleeding who are hemodynamically stable, either colonoscopy or nuclear medicine scans can be used for diagnosis. Colonoscopy will identify the site of bleeding more frequently than other methods and can provide effective treatment. The use of emergent TAI is most appropriate for patients with massive LGI bleeding, because contrast extravasation is more likely to be seen on diagnostic arteriography, and this can then guide therapeutic embolization. Transcatheter arteriography and intervention may successfully stop bleeding in 40% to 85% of patients. Major complications from TAI are uncommon, but the risk for rebleeding is quite high, particularly when LGI bleeding originates from the jejunum, ileum, or cecum. Transcatheter arteriography and intervention is most effective for the treatment of bleeding from colonic diverticulitis and for bleeding occurring distal to the cecum. The choice of colonoscopy, TAI, or surgery for hemodynamically unstable patients with acute LGI bleeding will depend on institutional expertise and whether the site of bleeding has been localized.

Interventional management of lower gastrointestinal bleeding

Lower gastrointestinal bleeding (LGIB) arises from a number of sources and is a significant cause of hospitalization and mortality in elderly patients. Whereas most episodes of acute LGIB resolve spontaneously with conservative management, an important subset of patients requires further diagnostic workup and therapeutic intervention. Endovascular techniques such as microcatheter embolization are now recognized as safe, effective methods for controlling LGIB that is refractory to endoscopic intervention. In addition, multidetector CT has shown the ability to identify areas of active bleeding in a non-invasive fashion, enabling more focused intervention. Given the relative strengths and weaknesses of various diagnostic and treatment modalities, a close working relationship between interventional radiologists, gastroenterologists and diagnostic radiologists is necessary for the optimal management of LGIB patients.