How to differentiate sites of gastrointestinal bleeding in patients with hematochezia by using clinical factors? Gastroenterol Res Pract. 2013;2013:265076. [PMID: 24348531 PMCID: PMC3852082 DOI: 10.1155/2013/265076]

Emergency medicine updates: Lower gastrointestinal bleeding

INTRODUCTION

Lower gastrointestinal bleeding (LGIB) is a condition commonly seen in the emergency department. Therefore, it is important for emergency medicine clinicians to be aware of the current evidence regarding the diagnosis and management of this disease.

OBJECTIVE

This paper evaluates key evidence-based updates concerning LGIB for the emergency clinician.

DISCUSSION

LGIB is most commonly due to diverticulosis or anorectal disease, though there are a variety of etiologies. The majority of cases resolve spontaneously, but patients can have severe bleeding resulting in hemodynamic instability. Initial evaluation should focus on patient hemodynamics, the severity of bleeding, and differentiating upper gastrointestinal bleeding from LGIB. Factors associated with LGIB include prior history of LGIB, age over 50 years, and presence of blood clots per rectum. Computed tomography angiography is the imaging modality of choice in those with severe bleeding to diagnose the source of bleeding and guide management when embolization is indicated. Among stable patients without severe bleeding, colonoscopy is the recommended modality for diagnosis and management. A transfusion threshold of 7 g/dL hemoglobin is recommended based on recent data and guidelines (8 g/dL in those with myocardial ischemia), though patients with severe bleeding and hemodynamic instability should undergo emergent transfusion. Anticoagulation reversal may be necessary. If bleeding does not resolve, embolization or endoscopic therapies are necessary. There are several risk scores that can predict the risk of adverse outcomes; however, these scores should not replace clinical judgment in determining patient disposition.

CONCLUSIONS

An understanding of literature updates can improve the care of patients with LGIB.

Preclinical study of a novel ingestible bleeding sensor for upper gastrointestinal bleeding

BACKGROUND/AIMS

Upper gastrointestinal bleeding (UGIB) is a life-threatening condition that necessitates early identification and intervention and is associated with substantial morbidity, mortality, and socioeconomic burden. However, several diagnostic challenges remain regarding risk stratification and the optimal timing of endoscopy. The PillSense System is a noninvasive device developed to detect blood in patients with UGIB in real time. This study aimed to assess the safety and performance characteristics of PillSense using a simulated bleeding model.

METHODS

A preclinical study was performed using an in vivo porcine model (14 animals). Fourteen PillSense capsules were endoscopically placed in the stomach and blood was injected into the stomach to simulate bleeding. The safety and sensitivity of blood detection and pill excretion were also investigated.

RESULTS

All the sensors successfully detected the presence or absence of blood. The minimum threshold was 9% blood concentration, with additional detection of increasing concentrations of up to 22.5% blood. All the sensors passed naturally through the gastrointestinal tract.

CONCLUSION

This study demonstrated the ability of the PillSense System sensor to detect UGIB across a wide range of blood concentrations. This ingestible device detects UGIB in real time and has the potential to be an effective tool to supplement the current standard of care. These favorable results will be further investigated in future clinical studies.

LONG-HOSP Score: A Novel Predictive Score for Length of Hospital Stay in Acute Lower Gastrointestinal Bleeding - A Multicenter Nationwide Study

INTRODUCTION

Length of stay (LOS) in hospital affects cost, patient quality of life, and hospital management; however, existing gastrointestinal bleeding models applicable at hospital admission have not focused on LOS. We aimed to construct a predictive model for LOS in acute lower gastrointestinal bleeding (ALGIB).

METHODS

We retrospectively analyzed the records of 8,547 patients emergently hospitalized for ALGIB at 49 hospitals (the CODE BLUE-J Study). A predictive model for prolonged hospital stay was developed using the baseline characteristics of 7,107 patients and externally validated in 1,440 patients. Furthermore, a multivariate analysis assessed the impact of additional variables during hospitalization on LOS.

RESULTS

Focusing on baseline characteristics, a predictive model for prolonged hospital stay was developed, the LONG-HOSP score, which consisted of low body mass index, laboratory data, old age, nondrinker status, nonsteroidal anti-inflammatory drug use, facility with ≥800 beds, heart rate, oral antithrombotic agent use, symptoms, systolic blood pressure, performance status, and past medical history. The score showed relatively high performance in predicting prolonged hospital stay and high hospitalization costs (area under the curve: 0.70 and 0.73 for derivation, respectively, and 0.66 and 0.71 for external validation, respectively). Next, we focused on in-hospital management. Diagnosis of colitis or colorectal cancer, rebleeding, and the need for blood transfusion, interventional radiology, and surgery prolonged LOS, regardless of the LONG-HOSP score. By contrast, early colonoscopy and endoscopic treatment shortened LOS.

CONCLUSIONS

At hospital admission for ALGIB, our novel predictive model stratified patients by their risk of prolonged hospital stay. During hospitalization, early colonoscopy and endoscopic treatment shortened LOS.

Making Hematochezia of Unknown Origin Known: A Retrospective Analysis

INTRODUCTION

Hematochezia is observed frequently in daily practice. However, natural hemostasis often prevents identification of the bleeding source during observations. This study was conducted to clarify risk factors related to rebleeding in hematochezia patients without an identified cause of bleeding.

METHODS

We analyzed patients who were admitted to Dokkyo Medical University Hospital during April 1, 2009, through March 31, 2015, with the chief complaint of hematochezia. Main outcome measures included the rebleeding rate and the period until rebleeding in hematochezia patients without an identified bleeding source.

RESULTS

We selected 159 patients for analyses. Rebleeding was observed in 46 (28.9%) of 159 patients. The median period until first rebleeding was 166 days (2-3,046 days). Univariate analysis indicated that risk factors for rebleeding were male gender (p = 0.029), higher age (p = 0.023), antithrombotic medicines (p = 0.047), lower hemoglobin on admission (p = 0.024), and the presence of diverticula (p = 0.002). Multivariate analysis indicated the presence of diverticula (p = 0.023) and male gender (p = 0.043) as rebleeding risk factors.

DISCUSSION/CONCLUSION

In patients with hematochezia of unknown origin, risk factors for rebleeding indicated in this study, especially the presence of diverticula and male gender, should be given particular attention by physicians.

Acute Upper Non-variceal and Lower Gastrointestinal Bleeding

Acute gastrointestinal (GI) bleeding is a common surgical emergency requiring hospital admission and associated with high morbidity and mortality. Appropriate decision-making is essential to make a prompt diagnosis, accurate risk assessment, and proper resuscitation of patients with gastrointestinal bleeding. Despite multiple randomized trials and meta-analyses, there is still controversy on various management issues like appropriate risk stratification, the timing of endoscopy, choosing an appropriate endoscopic, and radiological intervention in these groups of patients. As the usage of nonsteroidal anti-inflammatory drugs, antiplatelet, and antithrombotic agents is common in patients with gastrointestinal bleeding, the physician is challenged with proper management of these drugs. The present review summarizes the current strategies for risk stratification, localization of bleeding source, endoscopic and radiological intervention in patients with acute nonvariceal upper GI, middle GI, and lower GI bleeding.

Diagnostic evaluation of urea nitrogen/creatinine ratio in dogs with gastrointestinal bleeding

Background

Urea nitrogen/creatinine ratio (UCR) is a marker for upper gastrointestinal bleeding (GIB) in people.

Objectives

To assess the usefulness of UCR to predict occult GIB and distinguish upper from lower GIB in dogs.

Animals

Eighty‐nine dogs with GIB and 65 clinically healthy dogs. Dogs were grouped according to 65 overt GIB and 24 occult GIB, and based on lesion localization (37 upper, 13 lower, and 8 both).

Methods

Seventy‐four dogs were included retrospectively and 15 dogs prospectively. Serum urea nitrogen and creatinine concentrations, UCR, hemoglobin concentration, hematocrit, mean corpuscular volume, and mean corpuscular hemoglobin concentration were compared between groups. Logistic regression models were fitted to assess if variables could distinguish occult GIB from being healthy and upper from lower GIB.

Results

The UCR was significantly higher in dogs with overt GIB compared to control dogs (P = .02) and dogs with occult GIB (P = .05). The UCR was not significantly associated with occult GIB vs being healthy, or upper vs lower GIB (P > .05 each). Dogs with higher hemoglobin concentration and hematocrit had significantly lower odds of having occult GIB than being healthy (P < .0001 each).

Conclusions and Clinical Importance

The UCR does not seem to be a clinically useful marker of occult GIB and appears to have poor discriminatory ability between upper and lower GIB. An increased UCR in a dog without signs of overt GIB, especially if its hematocrit is within the middle or upper reference interval, does not appear to warrant prompt prescription of gastrointestinal protectants.

Explainable Machine Learning Model for Predicting GI Bleed Mortality in the Intensive Care Unit

INTRODUCTION

Acute gastrointestinal (GI) bleed is a common reason for hospitalization with 2%-10% risk of mortality. In this study, we developed a machine learning (ML) model to calculate the risk of mortality in intensive care unit patients admitted for GI bleed and compared it with APACHE IVa risk score. We used explainable ML methods to provide insight into the model's prediction and outcome.

METHODS

We analyzed the patient data in the Electronic Intensive Care Unit Collaborative Research Database and extracted data for 5,691 patients (mean age = 67.4 years; 61% men) admitted with GI bleed. The data were used in training a ML model to identify patients who died in the intensive care unit. We compared the predictive performance of the ML model with the APACHE IVa risk score. Performance was measured by area under receiver operating characteristic curve (AUC) analysis. This study also used explainable ML methods to provide insights into the model's outcome or prediction using the SHAP (SHapley Additive exPlanations) method.

RESULTS

The ML model performed better than the APACHE IVa risk score in correctly classifying the low-risk patients. The ML model had a specificity of 27% (95% confidence interval [CI]: 25-36) at a sensitivity of 100% compared with the APACHE IVa score, which had a specificity of 4% (95% CI: 3-31) at a sensitivity of 100%. The model identified patients who died with an AUC of 0.85 (95% CI: 0.80-0.90) in the internal validation set, whereas the APACHE IVa clinical scoring systems identified patients who died with AUC values of 0.80 (95% CI: 0.73-0.86) with P value <0.001.

DISCUSSION

We developed a ML model that predicts the mortality in patients with GI bleed with a greater accuracy than the current scoring system. By making the ML model explainable, clinicians would be able to better understand the reasoning behind the outcome.

Upper Gastrointestinal Bleeding

Although its incidence is decreasing, upper gastrointestinal bleeding represents a significant cause of morbidity and mortality. We present the most common sources of upper gastrointestinal bleeding and treatments.

Blood Urea Nitrogen to Creatinine ratio in Differentiation of Upper and Lower Gastrointestinal Bleedings; a Diagnostic Accuracy Study

INTRODUCTION

Finding easily accessible and non-invasive methods for differentiating various sources of gastrointestinal (GI) bleeding before performing endoscopy and colonoscopy is of great interest. The present study was designed with the aim of evaluating the screening performance characteristics of blood urea nitrogen (BUN) to Creatinine (Cr) ratio in this regard.

METHODS

The present diagnostic accuracy study was performed on patients with acute GI bleeding presenting to emergency department from 2011 to 2016, in a retrospective manner. BUN/Cr ratio was calculated for all patients and its accuracy in differentiation of upper and lower GI bleedings, confirmed via endoscopy or colonoscopy, was evaluated.

RESULTS

A total of 621 patients with the mean age of 59.49±17.94 (5 - 93) years were studied (60.5% male). Area under the receiver operating characteristic (ROC) curve of BUN/Cr ratio for predicting the source of GI bleeding was 0.63 (95% CI: 0.57 - 0.68). Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios of BUN/Cr ratio at 35 cut-off point were 19.63% (95%CI: 16.69 - 23.45), 90.16% (95%CI: 83.11 - 94.88), 89.09 (95%CI: 81.35 - 93.98), 21.53 (95%CI: 18.09 - 25.39), 8.16 (95%CI:4.76 - 13.98), and 3.65 (95%CI: 3.44 - 3.87), respectively.

CONCLUSION

Considering the relatively proper specificity and positive predictive value of BUN/Cr ratio, in cases that bleeding source cannot be determined using other non-invasive methods, values higher than 35 can predict upper GI bleeding with high probability. However, due to the low sensitivity, values less than 35 are not diagnostic.

Initial management for acute lower gastrointestinal bleeding

Acute lower gastrointestinal bleeding (LGIB) is a common indication for hospital admission. Patients with LGIB often experience persistent or recurrent bleeding and require blood transfusions and interventions, such as colonoscopic, radiological, and surgical treatments. Appropriate decision-making is needed to initially manage acute LGIB, including emergency hospitalization, timing of colonoscopy, and medication use. In this literature review, we summarize the evidence for initial management of acute LGIB. Assessing various clinical factors, including comorbidities, medication use, presenting symptoms, vital signs, and laboratory data is useful for risk stratification of severe LGIB, and for discriminating upper gastrointestinal bleeding. Early timing of colonoscopy had the possibility of improving identification of the bleeding source, and the rate of endoscopic intervention, compared with elective colonoscopy. Contrast-enhanced computed tomography before colonoscopy may help identify stigmata of recent hemorrhage on colonoscopy, particularly in patients who can be examined immediately after the last hematochezia. How to deal with nonsteroidal anti-inflammatory drugs (NSAIDs) and antithrombotic agents after hemostasis should be carefully considered because of the risk of rebleeding and thromboembolic events. In general, aspirin as primary prophylaxis for cardiovascular events and NSAIDs were suggested to be discontinued after LGIB. Managing acute LGIB based on this information would improve clinical outcomes. Further investigations are needed to distinguish patients with LGIB who require early colonoscopy and hemostatic intervention.

Lower GI bleeding: a review of current management, controversies and advances

PURPOSE

Lower gastrointestinal (GI) bleeding is defined as bleeding distal to the ligament of Treitz. In the UK, it represents approximately 3 % of all surgical referrals to the hospital. This review aims to provide review of the current evidence regarding the management of this condition.

METHODS

Literature was searched using Medline, Pubmed, and Cochrane for relevant evidence by two researchers. This was conducted in a manner that enabled a narrative review of the evidence covering the aetiology, clinical assessment and management options of continuously bleeding patients.

FINDINGS

The majority of patients with acute lower GI bleeding can be treated conservatively. In cases where ongoing bleeding occurs, colonoscopy is still the first line of investigation and treatment. Failure of endoscopy and persistent instability warrant angiography, possibly preceded by CT angiography and proceeding to superselective embolisation. Failure of embolisation warrants surgical intervention.

CONCLUSIONS

There are still many unanswered questions. In particular, the development of a more reliable predictive tool for mortality, rebleeding and requirement for surgery needs to be the ultimate priority. There are a small number of encouraging developments on combination therapy with regard to angiography, endoscopy and surgery. Additionally, the increasing use of haemostatic agents provides an additional tool for the management of bleeding endoscopically in difficult situations.

Availability of blood urea nitrogen/creatinine ratio in gastrointestinal bleeding with melena in children

PURPOSE

The aims of our study were to evaluate the blood urea nitrogen to creatinine ratio (BUN/Cr ratio) for distinguishing between an upper and lower gastrointestinal bleeding (GIB), and differentiating between the two most common causes of upper gastrointestinal bleeding (UGIB) presenting with melena in children.

METHODS

Retrospective data of patients with GIB presenting with melena were analyzed. The data from 60 cases were reviewed including demographics, laboratory findings, diagnostic modalities and results, treatments, and transfusions.

RESULTS

Among the 60 cases, UGIB and lower gastrointestinal bleeding (LGIB) were found in 35 cases (58.3%) and 14 cases (23.3%), respectively. The two common causes of UGIB were varices (37.1%), and peptic ulcer diseases (PUD) (31.4%). The BUN/Cr ratio of 30 or greater was higher in UGIB than LGIB (odds ratio [OR], 6.9; 95% confidence interval [95% CI], 1.3-37.2). In UGIB, the BUN/Cr ratio of the varices group was higher than that of the PUD group (p=0.015). The OR for the BUN/Cr ratio appeared as 1.2 per unit increase in the varices group than the PUD group (95% CI, 1.03-1.3). There was no difference between the PUD group and Meckel's diverticulum group.

CONCLUSION

The BUN/Cr ratio was not uneven in differentiating UGIB from LGIB of children with melena in our study. This suggests that BUN/Cr ratio should be interpreted carefully.