Colonoscopy in Acute Lower Gastrointestinal Bleeding: Diagnosis, Timing, and Bowel Preparation

Time to Endoscopy or Colonoscopy Among Adults Younger Than 50 Years With Iron-Deficiency Anemia and/or Hematochezia in the VHA

Importance

To date, the diagnostic test completion rate and the time to diagnostic endoscopy or colonoscopy among adults with iron-deficiency anemia (IDA) and/or hematochezia have not been well characterized.

Objective

To evaluate the diagnostic test completion rate and the time to diagnostic testing among veterans younger than 50 years with IDA and/or hematochezia.

Design, Setting, and Participants

This cohort study was conducted within the Veterans Health Administration between October 1, 1999, and December 31, 2019, among US veterans aged 18 to 49 years from 2 separate cohorts: those with a diagnosis of IDA (n = 59 169) and those with a diagnosis of hematochezia (n = 189 185). Statistical analysis was conducted from August 2021 to August 2023.

Exposures

Diagnostic testing factors included age, sex, race and ethnicity, Veterans Health Administration geographic region, and hemoglobin test value (IDA cohort only).

Main Outcomes and Measures

Primary outcomes of diagnostic testing were (1) bidirectional endoscopy after diagnosis of IDA and (2) colonoscopy or sigmoidoscopy after diagnosis of hematochezia. The association between diagnostic testing factors and diagnostic test completion was examined using Poisson models.

Results

There were 59 169 veterans with a diagnosis of IDA (mean [SD] age, 40.7 [7.1] years; 30 502 men [51.6%]), 189 185 veterans with a diagnosis of hematochezia (mean [SD] age, 39.4 [7.6] years; 163 690 men [86.5%]), and 2287 veterans with IDA and hematochezia (mean [SD] age, 41.6 [6.9] years; 1856 men [81.2%]). The cumulative 2-year diagnostic workup completion rate was 22% (95% CI, 22%-22%) among veterans with IDA and 40% (95% CI, 40%-40%) among veterans with hematochezia. Veterans with IDA were mostly aged 40 to 49 years (37 719 [63.7%]) and disproportionately Black (24 480 [41.4%]). Women with IDA (rate ratio [RR], 0.42; 95% CI, 0.40-0.43) had a lower likelihood of diagnostic test completion compared with men with IDA. Black (RR, 0.65; 95% CI, 0.62-0.68) and Hispanic (RR, 0.88; 95% CI, 0.82-0.94) veterans with IDA were less likely to receive diagnostic testing compared with White veterans with IDA. Veterans with hematochezia were mostly White (105 341 [55.7%]). Among veterans with hematochezia, those aged 30 to 49 years were more likely to receive diagnostic testing than adults younger than 30 years of age (age 30-39 years: RR, 1.15; 95% CI, 1.12-1.18; age 40-49 years: RR, 1.36; 95% CI, 1.33-1.40). Hispanic veterans with hematochezia were less likely to receive diagnostic testing compared with White veterans with hematochezia (RR, 0.96; 95% CI, 0.93-0.98).

Conclusions and Relevance

In the cohorts of veterans younger than 50 years with IDA and/or hematochezia, the diagnostic test completion rate was low. Follow-up was less likely among female, Black, and Hispanic veterans with IDA and Hispanic veterans with hematochezia. Optimizing timely follow-up across social and demographic groups may contribute to improving colorectal cancer outcomes and mitigate disparities.

Evaluation and Management of Lower GI Bleeding

CASE SUMMARY

A 73-year-old woman, who had received apixaban for therapeutic anticoagulation, presented with hypotension and hematochezia. After resuscitation, diagnostic colonoscopy revealed multiple polyps and old blood within the colonic lumen, but no active bleeding (Fig. 1). Nasogastric lavage and subsequent EGD were unremarkable. During her hospitalization, she was admitted to the intensive care unit with worsening anemia, hypotension, and hematochezia. CT angiogram showed extravasation at the transverse colon (Fig. 1). Formal angiogram was unable to localize the source of bleeding, despite provocation. Given the localization on CT angiography and the patient's clinical deterioration, she underwent hand-assisted segmental transverse colectomy. Surgical pathology was notable for multiple adenomas without dysplasia. The patient had no further episodes of GI bleeding after resection.

Contrast extravasation on computed tomography angiography in patients with hematochezia or melena: Predictive factors and associated outcomes

PURPOSE

The purpose of this study was to identify variables associated with extravasation on computed tomography angiography (CTA) in patients with hematochezia/melena and compare the outcome of patients with extravasation on CTA to those without extravasation.

MATERIAL AND METHODS

Ninety-four patients (51 men, 38 women; mean age, 69 ± 16 [SD] years) who underwent CTA within 30 days of hematochezia/melena were included. Variables associated with extravasation on CTA were searched using univariable and multivariable analyses. Outcomes of patients with visible extravasation on CTA were compared with those without visible extravasation.

RESULTS

One hundred and one CTA examinations were included. Extravasation was observed on 26/101 CTA examinations (26%). At multivariable analysis the need for vasopressor drugs (odds ratio [OR], 7.6; P = 0.040), high transfusion requirements (> 2 blood units) (OR, 7.1; P = 0.014), CTA performed on the day of a hemorrhagic event (OR, 46.2; P = 0.005) and repeat CTA (OR, 27.8; P = 0.011) were independently associated with extravasation on CTA. Extravasation on CTA was followed by a therapeutic procedure in 25/26 CTAs (96%; 26 patients) compared to 13/75 CTAs (17%; 68 patients) on which no extravasation was present (P < 0.001). No patients (0/26; 0%) with contrast extravasation on CTA died while 8 patients (8/61; 13%) without contrast extravasation died, although the difference was not significant (P = 0.099).

CONCLUSION

Extravasation on CTA in the setting of hematochezia or melena is especially seen in clinically unstable patients who receive more than two blood units. Presence of active extravasation on CTA leads to more frequent application of a therapeutic procedure; however, this does not significantly affect patient outcome.

The role of colonoscopy and endotherapy in the management of lower gastrointestinal bleeding

Colonoscopy is an integral diagnostic and therapeutic tool in the management of patients with lower gastrointestinal bleeding (LGIB). After resuscitation, reversal of coagulopathy, and exclusion of a proximal source of bleeding, colonoscopy should be performed in most patients with LGIB. Bowel preparation, typically with polyethylene glycol based solutions, is needed to closely inspect the colonic mucosa for bleeding sources. Colonoscopy within 24 h is recommended for high-risk patients with ongoing bleeding, although there is limited evidence that this strategy improves clinical outcomes. When active or stigmata of bleeding is detected, endoscopic intervention is indicated and can reduce future rebleeding. The most common options for endoscopic intervention include clipping, endoscopic band ligation, and coagulation, however rigorous head-to-head comparisons of different endoscopic tools are unavailable. Future research is needed to determine the optimal timing of colonoscopy, appropriate reversal strategies for patients on antithrombotics, and the most effective endoscopic hemostatic therapy.