Hemodynamic instability and shock are associated with untoward outcomes in gastrointestinal bleeding. However, there are no studies in the existing literature on the proportion of patients who developed these outcomes after gastrointestinal bleeding.

To determine the pooled event rates in the available literature and specify them based on the bleeding source.

The protocol was registered on PROSPERO in advance (CRD42021283258). A systematic search was performed in three databases (PubMed, EMBASE, and CENTRAL) on 14th October 2021. Pooled proportions with 95%CI were calculated with a random-effects model. A subgroup analysis was carried out based on the time of assessment (on admission or during hospital stay). Heterogeneity was assessed by Higgins and Thompson's I2 statistics. The Joanna Briggs Institute Prevalence Critical Appraisal Tool was used for the risk of bias assessment. The Reference Citation Analysis (https://www.referencecitationanalysis.com/) tool was applied to obtain the latest highlight articles.

We identified 11589 records, of which 220 studies were eligible for data extraction. The overall proportion of shock and hemodynamic instability in general gastrointestinal bleeding patients was 0.25 (95%CI: 0.17-0.36, I2 = 100%). In non-variceal bleeding, the proportion was 0.22 (95%CI: 0.14-0.31, I2 = 100%), whereas it was 0.25 (95%CI: 0.19-0.32, I2 = 100%) in variceal bleeding. The proportion of patients with colonic diverticular bleeding who developed shock or hemodynamic instability was 0.12 (95%CI: 0.06-0.22, I2 = 90%). The risk of bias was low, and heterogeneity was high in all analyses.

One in five, one in four, and one in eight patients develops shock or hemodynamic instability on admission or during hospitalization in the case of non-variceal, variceal, and colonic diverticular bleeding, respectively.

The aim of study is to identify the frequency of acute complications and imaging findings at gastro-intestinal transit (GI) and computerised tomography (CT) in a group of obese patients who developed clinical suspicion of acute complications (painful and meteoric abdomen, nausea, vomiting, fever, intestinal blockage) in post bariatric surgery.

We retrospectively review 954 obese patients who underwent bariatric surgery between 2013 and 2019. The study included 72 patients who developed clinical suspicion of acute complications (painful and meteoric abdomen, nausea, vomiting, fever, intestinal blockage) within 6 days of bariatric surgery of sleeve gastrectomy, gastric banding, gastric bypass with Roux loop confirmed by CT, and who underwent a gastrointestinal transit before the CT examination.

GI exam allowed visualisation of 58% of complications. Analysing the data for each surgical technique, 46 post-operative complications were found involve gastric banding. The most frequent was bandage migration (26 cases, 56 %), identified in all cases at GI transit and then confirmed on CT.

The study suggests that CT should be used to clarify all doubtful or clinically discordant GI transit exam results. The participation of a radiologist in qualification and post-operative evaluation is important for bariatric surgery patients.