External validation of the Oakland score to assess safe hospital discharge among adult patients with acute lower gastrointestinal bleeding in an accident and emergency department in Hong Kong

Abstract

Objective: To externally validate the use of the Oakland score in identification of low-risk lower gastrointestinal bleeding patients who can be safely managed without hospitalisation in an accident and emergency department in Hong Kong. Methods: This single-centre retrospective cohort study included adult patients who attended the accident and emergency department for lower gastrointestinal bleeding and were subsequently admitted to hospital from 1 January 2020 to 31 December 2020. Safe discharge was defined as absence of all of the following adverse outcomes after hospital presentation: blood transfusion; therapeutic colonoscopy, mesenteric embolisation, or laparotomy for bleeding; in-hospital death (all causes); and readmission with subsequent lower gastrointestinal bleeding within 28 days. The sensitivities, specificities and area under the receiver-operating characteristic curve of the Oakland score were calculated. Results: Among 376 patients who were included in this study, 114 (30.3%) of them experienced one or more adverse outcomes. The area under the receiver-operating characteristic curve for safe discharge was 0.88 (95% confidence interval, 0.84–0.91). Using an Oakland score threshold of ⩽8 points as in the original derivation study can achieve 100% sensitivity (95% confidence interval, 96.8%–100%) and 7.3% specificity (95% confidence interval, 4.4%–11.1%) for safe discharge. When the Oakland score threshold was extended to ⩽11 points, a much greater proportion of low-risk patients could be identified, with 97.4% sensitivity (95% confidence interval, 92.5%–99.5%) and 32.8% specificity (95% confidence interval, 27.2%–38.9%) for safe discharge. Conclusion: The Oakland score performed well in identification of lower gastrointestinal bleeding patients who were at low risk of experiencing adverse outcomes and could thus be safely managed without hospitalisation. Extension of the Oakland score threshold to ⩽11 points can allow identification of a greater proportion of low-risk patients while sensitivity is reasonably maintained.

External Validation of the Oakland Score for Predicting Safe Discharge in Patients Presenting With Lower Gastrointestinal Bleeding at the William Harvey Hospital in the United Kingdom

“…However, there were more adverse events [9]. Furthermore, the Fong study found that a threshold of ≤11 points resulted in a sensitivity of safe discharge at 97% [10]. Similar results were also seen in the 2021 Martin et al study.…”

“…As seen in other external validation studies such as the Oakland et al or Fong study, the AUROC for the ability of the Oakland score to safe discharge in LGIB patients was 0.84 compared to 0.87 and 0.88, respectively [9,10]. This is therefore suggesting that the Oakland score is a good tool to predict safe discharge in this cohort of patients as the AUROC > 0.8 [8].…”

“…However, this does not always happen and therefore it is possible that more patients with LGIB could have been missed. Finally, because of the above limitations, the study has a smaller sample size compared to other external validation studies although similar results were seen [9,10].…”

“…Similarly, patients who suffered from comorbidities were not at an increased risk of developing adverse outcomes -only 16 patients out of 51 had co-morbidities and adverse outcomes. However, compared to other studies validating the Oakland score [9,10], the sample size of the cohort was smaller and therefore the relationship between anticoagulation use, comorbidities, and the risk of adverse outcomes could not be studied accurately.…”

“…As a predictor for mortality, a recent study by Yeon et al showed that the AIMS65 score and ABC score were better at predicting 30-day mortality than the Oakland score [14]. It has been suggested in other studies that a higher cut of 10 or more could be used [9,10]. Indeed, 38 patients with a score >8 were safely discharged.…”