The utilization of CTA in management of gastrointestinal bleeding in a tertiary care center ED. Are we using it enough?

The Accuracy of Computed Tomography Angiography Compared With Technetium-99m Labelled Red Blood Cell Scintigraphy for the Diagnosis and Localization of Acute Gastrointestinal Bleeding: A Systematic Review and Meta-Analysis

Imaging tests are commonly used as an initial or early investigation for patients presenting with suspected acute gastrointestinal bleeding (AGIB). However, controversy remains regarding which of two frequently used modalities, computed tomography angiography (CTA) or technetium-99m labelled red blood cell scintigraphy (RBCS), is most accurate. This systematic review and meta-analysis was performed to compare the accuracy of CTA and RBCS for the detection and localization of AGIB. Five electronic databases were searched with additional manual searching of reference lists of relevant publications identified during the search. Two reviewers independently performed screening, data extraction and methodological assessments. Where appropriate, the bivariate model was used for meta-analysis of sensitivities and specificities for the detection of bleeding and Freeman-Tukey double-arcsine transformation used for meta-analysis of proportions of correctly localized bleeding sites. Forty-four unique primary studies were included: twenty-two investigating CTA, seventeen investigating RBCS and five investigating both modalities. Meta-analysis produced similar pooled sensitivities; 0.83 (95% CI 0.74-0.90) and 0.84 (0.68-0.92) for CTA and RBCS respectively. Pooled specificity for CTA was higher than RBCS; 0.90 (0.72-0.97) and 0.84 (0.71-0.91) respectively. However, differences were not statistically significant. CTA was superior to RBCS in correctly localizing bleeding; pooled proportions of 1.00 (0.98-1.00) and 0.90 (0.83-0.96) respectively (statistically significant difference, P < 0.001). There is no evidence that CTA and RBCS have different diagnostic performance with respect to the detection of AGIB. However, CTA is superior to RBCS in terms of correctly localising the bleeding site, supporting usage of CTA over RBCS as the first line imaging investigation.

Clinical Predictors of a Positive Ct Angiogram Study Used for the Evaluation of Acute Gastrointestinal Hemorrhage

BACKGROUND

Acute gastrointestinal (GI) bleeding is one of the leading causes of emergency department visits and hospital admissions. CT angiography (CTA) has had an expanding role in the evaluation of acute GI bleeding because it is rapidly performed, widely available, reasonably sensitive and provides precise localization when positive. We attempted to identify patient and clinical characteristics that predict CTA results in order to help guide the utilization of this modality in patients with acute GI bleeding.

METHODS

In this retrospective study, we analyzed all CTAs performed for the evaluation of GI bleeding in the Duke University healthcare system between October 2019 and March 2020. We captured patient characteristics including age, sex, vital signs, hemoglobin, platelets, PT/INR, and anticoagulation status. Study indications were grouped by suspected source of bleeding: upper GI bleeding (hematemesis or coffee-ground emesis) vs small bowel bleeding (melena or "dark stools") vs lower GI bleeding (hematochezia or bright red blood per rectum (BRBPR)). Chi-square, Wilcoxon, t test, and multivariate logistic regression were used to describe and assess the relationship between patient characteristics and study outcomes (Table 1). Table 1 Univariate analysis of patient characteristics by CT angiography outcome Patient Characteristics by Positive CT for GI Bleed No (N = 274) Yes (N = 43) Total (N = 317) p value Gender 0.45¹  Female 138 (50.4%) 19 (44.2%) 157 (49.5%)  Male 136 (49.6%) 24 (55.8%) 160 (50.5%) Age, median (Q1,Q3) 65 (51,75) 70 (62,80) 66 (52, 76)  < 0.01² Heart rate, median (Q1,Q3) 86 (74,100) 89 (72,98) 86 (74, 99) 0.78² MAP, mean (SD) 87.32 (15.52) 81.72 (16.53) 86.56 0.03³ Shock index, median (Q1,Q3) 0.70 (0.58, 0.85) 0.78 (0.55, 1.00) 0.71 (0.58, 0.85) 0.35² Hemoglobin 0.33²  N 273 43 316  Median (Q1, Q3) 8.50 (6.90, 11.00) 7.70 (6.50, 11.30) 8.45 (6.90, 11.00) Baseline hemoglobin 0.20²  N 258 39 297  Median (Q1, Q3) 11.20 (9.40, 13.00) 12.00 (9.40, 14.00) 11.20 (9.40, 13.00) Hemoglobin drop from baseline 0.06²  N 258 39 297  Median (Q1, Q3) 2.10 (0.60, 3.70) 2.70 (1.20, 4.80) 2.20 (0.70, 3.80) Platelets, median (Q1, Q3) 219.5 (141, 301) 183 (139, 246) 217 (139, 282) 0.10² INR 0.27²  N 263 42 305  Median (Q1, Q3) 1.10 (1.00, 1.30) 1.20 (1.00, 1.30) 1.10 (1.00, 1.30) Anticoagulation 0.13¹  No 155 (56.6%) 19 (44.2%) 174 (54.9%)  Yes 119 (43.4%) 24 (55.8%) 143 (45.1%) Upper GI bleeding 0.40¹  No 251 (91.6%) 41 (95.3%) 292 (92.1%)  Yes 23 (8.4%) 2 (4.7%) 25 (7.9%) Small Bowel bleeding 0.76¹  No 216 (78.8%) 33 (76.7%) 249 (78.5%)  Yes 58 (21.2%) 10 (23.3%) 68 (21.5%) Lower GI bleeding 0.09¹  No 134 (48.9%) 15 (34.9%) 149 (47.0%)  Yes 140 (51.1%) 28 (65.1%) 168 (53.0%) ¹Chi-Square ²Wilcoxon ³Equal Variance T-Test RESULTS: A total of 317 patients underwent CTA between October 2019 and March 2020. Forty-three patients (13.6%) had a CTA positive for active bleeding. Multivariable logistic regression showed that after controlling for age, mean arterial pressure (MAP) and indication, only a hemoglobin drop from baseline was significantly associated with a positive CTA. For each 1 g / dL drop in hemoglobin from the patient's baseline, the odds of a positive CT increased by 1.17 (OR 1.17 95% CI 1.00 - 1.36, p = 0.04). Age (OR 1.02 95% CI 0.99 - 1.04, p = 0.06) and hematochezia / BRBPR (OR 2.09 95% CI 0.94-4.64, p = 0.07) approached statistical significance.

CONCLUSIONS

In patients who present to the hospital with GI bleeding, CTA can be a helpful triage tool that is most helpful in older patients with suspected lower GI bleeding with a drop in hemoglobin from baseline. Other clinical factors including MAP and the use of anticoagulants were not predictive of a positive CTA.

Gastrointestinal bleeding during the transcatheter aortic valve replacement perioperative period: A Review

With the aging of the population, the incidence of senile degenerative valvular heart disease is expected to increase. Transcatheter aortic valve replacement (TAVR) has been used for patients at lower surgical risk with symptomatic severe aortic valve stenosis. Because of the improvements in TAVR technology and increasing experience of the operators, TAVR is regarded as a safe and feasible procedure. Bleeding events during the TAVR perioperative period, especially gastrointestinal (GI) bleeding, have been proven to be related to the long-term prognosis and mortality. Elderly patients with valvular heart disease are susceptible to GI bleeding because of their use of antithrombotic drugs, physical damage of coagulation factors, and GI angiodysplasia. Frequent GI bleeding and low levels of preoperative hemoglobin increase the risk of TAVR, especially for elderly patients. Because of these risks, which are easily overlooked, we should focus more attention on the perioperative management of TAVR. Reasonable screening tools, including blood examinations, risk evaluation scales, and endoscopy, are beneficial to the prevention of complications that can occur during the perioperative period. Additionally, medical therapy can safely help patients at high-risk for bleeding patients throughout the perioperative period. This study aimed to characterize the pathology of TAVR patients and discuss treatment strategies for GI bleeding during the perioperative period.

Acute Lower Gastrointestinal Bleeding in an Emergency Department and Performance of the SHA2PE Score: A Retrospective Observational Study

Lower gastrointestinal bleeding (LGIB) is a frequent cause of emergency department (ED) consultation, leading to investigations but rarely to urgent therapeutic interventions. The SHA₂PE score aims to predict the risk of hospital-based intervention, but has never been externally validated. The aim of our single-center retrospective study was to describe patients consulting our ED for LGIB and to test the validity of the SHA₂PE score. We included 251 adult patients who consulted in 2017 for hematochezia of <24 h duration; 53% were male, and the median age was 54 years. The most frequent cause of LGIB was unknown (38%), followed by diverticular disease and hemorrhoids (14%); 20% had an intervention. Compared with the no-intervention group, the intervention group was 26.5 years older, had more frequent bleeding in the ED (47% vs. 8%) and more frequent hypotension (8.2% vs. 1.1%), more often received antiplatelet drugs (43% vs. 18%) and anticoagulation therapy (28% vs. 9.5%), more often had a hemoglobin level of <10.5 g/dl (49% vs. 6.2%) on admission, and had greater in-hospital mortality (8.2% vs. 0.5%) (all p < 0.05). The interventions included transfusion (65%), endoscopic hemostasis (47%), embolization (8.2%), and surgery (4%). The SHA₂PE score predicted an intervention with sensitivity of 71% (95% confidence interval: 66–83%), specificity of 81% (74–86%), and positive and negative predictive values of 53% (40–65%) and 90% (84–95%), respectively. SHA₂PE performance was inferior to that in the original study, with a 1 in 10 chance of erroneously discharging a patient for outpatient intervention. Larger prospective validation studies are needed before the SHA₂PE score can be recommended to guide LGIB patient management in the ED.