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

Differences in emergency endoscopy outcomes according to gastrointestinal bleeding location

BACKGROUND AND AIM

With recent technological advances in the field of endoscopic hemostasis, the prognosis of patients with gastrointestinal (GI) bleeding has improved. However, few studies have reported on the clinical course of patients with GI bleeding. This study aimed to evaluate the differences in clinical outcomes of patients with lower GI bleeding (LGIB) compared with upper GI bleeding (UGIB) and the factors related to their prognosis.

METHODS

Patients who had undergone emergency endoscopy for GI bleeding were retrospectively reviewed. The severity of GI bleeding was evaluated using the Glasgow-Blatchford (GB), AIMS65, and NOBLADS scores. Patients in whom obvious GI bleeding relapsed and/or iron deficiency anemia persisted after emergency endoscopy were considered to exhibit rebleeding.

RESULTS

We reviewed 1697 consecutive patients and divided them into UGIB (1054 patients) and LGIB (643 patients) groups. The proportion of patients with rebleeding was significantly greater in the UGIB group than in the LGIB group; the mortality rate was significantly higher in the UGIB group than in the LGIB group. Multivariate analysis showed that a GB score ≥12 and an AIMS65 score ≥2 were significantly associated with rebleeding in the UGIB group, whereas a NOBLADS score ≥4 was significantly associated with rebleeding in the LGIB group. Notably, the influence of emergency endoscopy differed according to GI bleeding location.

CONCLUSIONS

The clinical course was significantly worse in patients with UGIB than in patients with LGIB. The influence of emergency endoscopy differed according to GI bleeding location.

Does Urgent Colonoscopy Improve Outcomes in the Management of Lower Gastrointestinal Bleeding?

Colonoscopy continues to be an essential diagnostic and therapeutic tool in the management of lower gastrointestinal bleeding (LGIB). Studies that have evaluated the role of urgent colonoscopy for treating LGIB have reached conflicting conclusions. We conducted a systematic review and meta-analysis to evaluate the role of urgent colonoscopy in several outcomes in patients with LGIB. We searched Medline, Embase, Scopus and Cochrane databases from inception to July 10, 2016 for comparative studies evaluating the role of urgent versus elective colonoscopy in the management of LGIB. We evaluated mortality, rate of rebleeding, length of stay in hospital, identification of bleeding source, stigmata of recent hemorrhage and need for surgery. Pooled odds ratios (OR) were calculated for dichotomous variables whereas standard mean differences were calculated for continuous variables. We assessed quality using the Cochrane tool and Newcastle Ottawa Scale for randomized controlled trials and observational studies, respectively. We used the GRADE framework to interpret our findings. A total of 6 studies (2 randomized controlled trials and 4 observational studies) with 23,419 patients (9,498 urgent colonoscopy and 13,921 elective colonoscopy) were included in this meta-analysis. Pooled ORs with 95% CI for mortality, rebleeding and identification of bleeding source were 0.84 (0.46-1.53), 1.18 (0.64-2.16) and 1.49 (0.86-2.59), respectively. Stigmata of recent hemorrhage were more readily identified with urgent colonoscopy OR 2.85 (1.90-4.28). There were no differences in requirement for surgery, length of hospital stay or rate of endoscopic intervention. However, these effect sizes were limited by considerable heterogeneity, which was probably due to studies being conducted in different countries having different criteria for discharge and on variations in the type of endoscopic therapy for stigmata of recent hemorrhage. In conclusion, among patients with acute LGIB, there is no evidence that urgent colonoscopy reduces mortality, rebleeding or requirement for surgery or that it improves the rate of identification of the bleeding source. However, urgent colonoscopy does increase the rate of detection of stigmata of recent hemorrhage.

[Value of urgent colonoscopy in diagnosis of severe acute lower gastrointestinal bleeding in patients with different bowel cleanliness]

OBJECTIVE

To investigate the value of urgent colonoscopy in the diagnosis of severe acute lower gastrointestinal bleeding and the optimal bowel preparation before examination.

METHODS

The clinical data were collected from 188 patients undergoing wither urgent or elective colonoscopy for severe acute lower gastrointestinal bleeding in Nanfang Hospital. Univariate analysis was used to assess the effect of the timing of colonoscopy on the diagnostic rate of hemorrhage, and a multivariate model which stratified bowel cleanliness was used to analyze the impact of bowel cleanliness on the diagnostic rate of urgent colonoscopy.

RESULTS

Of the 188 patients, 118 underwent urgent colonoscopy and 70 underwent elective colonoscopy examinations. The diagnostic rates were comparable between the two groups (44.1% vs 41.4%, P=0.724), but urgent colonoscopy resulted in a significantly higher diagnostic rate for identifying the bleeding source (32.2% vs 18.6%, P=0.041). The proportion of the patients taking oral laxatives was significantly lower in urgent colonoscopy group (P<0.001). Oral laxatives versus enema resulted in good, moderate, and poor bowel cleanliness in 63.6% vs 13.5%, 28.6% vs 24.3%, and 7.8% vs 62.2% of the patients (P<0.001). Univariate analysis indicated that good bowel cleanliness was associated with a significantly higher diagnostic rate of colonoscopy than poor bowel cleanliness (P=0.012). Multivariate analysis showed that with good bowel cleanliness, urgent colonoscopy yielded a significantly higher diagnostic rate than elective colonoscopy (P=0.030); subgroup analyses suggested that good bowel cleanliness improved the diagnostic rate of urgent colonoscopy as compared with poor bowel cleanliness (P=0.015).

CONCLUSION

In patients with good bowel cleanliness, urgent colonoscopy yields a higher diagnostic rate than elective colonoscopy for severe acute lower gastrointestinal bleeding. Poor bowel cleanliness resulting from bowel preparation by enema significantly lowers the diagnostic performance of urgent colonoscopy. Oral laxatives are recommended over enemas for bowel preparation before urgent colonoscopy when the patients have stable hemodynamics.

Achieving the best bowel preparation for colonoscopy

Bowel preparation is a core issue in colonoscopy, as it is closely related to the quality of the procedure. Patients often find that bowel preparation is the most unpleasant part of the examination. It is widely accepted that the quality of cleansing must be excellent to facilitate detecting neoplastic lesions. In spite of its importance and potential implications, until recently, bowel preparation has not been the subject of much study. The most commonly used agents are high-volume polyethylene glycol (PEG) electrolyte solution and sodium phosphate. There has been some confusion, even in published meta-analyses, regarding which of the two agents provides better cleansing. It is clear now that both PEG and sodium phosphate are effective when administered with proper timing. Consequently, the timing of administration is recognized as one of the central factors to the quality of cleansing. The bowel preparation agent should be administered, at least in part, a few hours in advance of the colonoscopy. Several low volume agents are available, and either new or modified schedules with PEG that usually improve tolerance. Certain adjuvants can also be used to reduce the volume of PEG, or to improve the efficacy of other agents. Other factors apart from the choice of agent can improve the quality of bowel cleansing. For instance, the effect of diet before colonoscopy has not been completely clarified, but an exclusively liquid diet is probably not required, and a low-fiber diet may be preferable because it improves patient satisfaction and the quality of the procedure. Some patients, such as diabetics and persons with heart or kidney disease, require modified procedures and certain precautions. Bowel preparation for pediatric patients is also reviewed here. In such cases, PEG remains the most commonly used agent. As detecting neoplasia is not the main objective with these patients, less intensive preparation may suffice. Special considerations must be made for patients with inflammatory bowel disease, including safety and diagnostic issues, so that the most adequate agent is chosen. Identifying neoplasia is one of the main objectives of colonoscopy with these patients, and the target lesions are often almost invisible with white light endoscopy. Therefore excellent quality preparation is required to find these lesions and to apply advanced methods such as chromoendoscopy. Bowel preparation for patients with lower gastrointestinal bleeding represents a challenge, and the strategies available are also reviewed here.

Timing of colonoscopy and outcomes in patients with lower GI bleeding: a nationwide population-based study

BACKGROUND

The role of urgent colonoscopy in lower GI bleeding (LGIB) remains controversial. Population-based studies on LGIB outcomes are lacking.

OBJECTIVE

To investigate the impact of the timing of colonoscopy on outcomes of patients with LGIB.

DESIGN

Cross-sectional study.

SETTING

Nationwide Inpatient Sample 2010.

PATIENTS

International Classification of Diseases, Ninth Revision, Clinical Modification codes identified patients with LGIB who underwent colonoscopy.

MAIN OUTCOME MEASUREMENTS

In-hospital mortality, length of stay, and hospitalization costs in patients who underwent early (≤24 hours) or delayed (>24 hours) colonoscopy.

RESULTS

A total of 58,296 discharges with LGIB were identified; 22,720 had a colonoscopy performed during the hospitalization. A total of 9156 patients had colonoscopy performed within 24 hours (early colonoscopy), and 13,564 had colonoscopy performed after 24 hours (delayed colonoscopy). There was no difference in mortality in patients with LGIB who had early versus delayed colonoscopy (0.3% vs 0.4%, P = .24). However, patients who underwent early colonoscopy had a shorter length of hospital stay (2.9 vs 4.6 days, P < .001), decreased need for blood transfusion (44.6% vs 53.8%, P < .001), and lower hospitalization costs ($22,142 vs $28,749, P < .001). On multivariate analysis, timing of colonoscopy did not affect mortality (adjusted odds ratio 1.5; 95% confidence interval, 0.7-2.7). On multivariate analysis, delayed colonoscopy was associated with an increase in the length of hospital stay by 1.6 days and an increase in hospitalization costs of $7187.

LIMITATIONS

Administrative dataset.

CONCLUSIONS

Early colonoscopy within 24 hours is associated with decreased length of hospital stay and hospitalization costs in patients with LGIB.

Pros and cons of colonoscopy in management of acute lower gastrointestinal bleeding

Acute lower gastrointestinal bleeding (LGIB) is a frequent gastrointestinal cause of hospitalization, particularly in the elderly, and its incidence appears to be on the rise. Endoscopic and radiographic measures are available for the evaluation and treatment of LGIB including flexible sigmoidoscopy, colonoscopy, angiography, radionuclide scintigraphy and multi-detector row computed tomography. Although no modality has emerged as the gold standard in the management of LGIB, colonoscopy is the current preferred initial test for the majority of the patients presenting with hematochezia felt to be from a colon source. Colonoscopy has the ability to diagnose all sources of bleeding from the colon and, unlike the radiologic modalities, does not require active bleeding at the time of the examination. In addition, therapeutic interventions such as cautery and endoclips can be applied to achieve hemostasis and prevent recurrent bleeding. Studies suggest that colonoscopy, particularly when performed early in the hospitalization, can decrease hospital length of stay, rebleeding and the need for surgery. However, results from available small trials are conflicting and larger, multicenter studies are needed. Compared to other management options, colonoscopy is a safe procedure with complications reported in less than 2% of patients, including those undergoing urgent examinations. The requirement of bowel preparation (typically 4 or more liters of polyethylene glycol), the logistical complexity of coordinating after-hours colonoscopy, and the low prevalence of stigmata of hemorrhage complicate the use of colonoscopy for LGIB, particularly in urgent situations. This review discusses the above advantages and disadvantages of colonoscopy in the management of acute lower gastrointestinal bleeding in further detail.