The goal of this observational study is to investigate the incidence, management, and outcomes of complications following bariatric surgery in patients in the United Kingdom. The main questions it aims to answer are:

• What is the prevalence of unplanned interventions due to complications following bariatric surgery in the UK?
• What are the current practices for managing these complications, and how do they impact patient outcomes?

Participants will:

Be identified from hospitals treating patients presenting with complications following bariatric surgery.

Have their data collected regarding demographics, surgical history, complications, treatments, and outcomes.

Researchers will compare different management strategies and their impact on patient outcomes, with the aim of identifying best practices to improve emergency bariatric care and factors leading to patients attending as an emergency.

The National Emergency Bariatric Surgery Audit (NEBSA) is an observational study aimed at investigating the incidence, management, and outcomes of complications following bariatric surgery in the United Kingdom. The detailed description of the protocol includes the following components:

Patient Recruitment and Data Collection:

Patients will be identified in hospitals across the UK where they present for an unplanned intervention to treat a complication related to or following bariatric surgery.

Data on demographics, surgical history, site and type of index bariatric surgery, comorbidities, complications, treatments, and outcomes will be collected through a combination of electronic health records and manual data extraction.

Quality Assurance Plan:

Data checks will be performed to ensure range, completeness and consistency with other data fields in the registry.

Data entry is restricted in most fields of the data form to ensure conformity of the entries and facilitate analysis.

Sample Size Assessment:

This is a prospective observational study, so a sample size assessment is not required. Data collection will continue for a six month period per centre then analysed to report any statistically significant findings.

Plan for Missing Data:

Missing data is reported back to the collaborating sites to complete.

Statistical Analysis Plan:

The Shapiro-Wilk test will be used to check variables for Gaussian distribution. Basic demographics will be presented as absolute numbers of participants with the respective percentage per group or as parameter mean and standard deviation or median and range, depending on distribution. For comparisons of interval-scaled variables, unpaired t tests will be performed. Nonparametric between-group testing will be undertaken with 2-tailed Mann-Whitney U tests. Additionally, the chi-square test or Fisher exact test will be applied to nominal scale data. Multivariable linear regression be performed for differences among baseline demographics. Analyses will be performed in RStudio with significance defined with p < 0.05.

The NEBSA will provide valuable insights into the prevalence, management, and outcomes of complications following bariatric surgery in the UK. By comparing different management strategies and their impact on patient outcomes, this study aims to identify best practices for emergency bariatric care, ultimately improving patient outcomes and overall healthcare quality. Another important aim is analysing the effect of patient demographics, and engagement with NHS specialised weight loss services on the choice of route for bariatric surgery.

Inclusion Criteria:

• Admissions from i) the emergency department, clinic, urgent care or primary care to the bariatric surgical team as an emergency; ii) from an inpatient team as an urgent referral; iii) a return to theatre following an elective bariatric procedure; iv) another hospital via patient transfer to a specialised unit.
• Participants undergoing any intervention or procedure to treat or diagnose bariatric complications, (e.g., OGDs, interventional radiology, surgery, supplemental enteral or parenteral nutrition).

Exclusion Criteria:

• age <18 years old
• have a length of stay <24 hrs.
• initial diagnosis of BSE is changed or if their readmission is found to be unrelated to previous bariatric surgery.

All patients admitted from these locations i) the emergency department, clinic, urgent care or primary care to the bariatric surgical team as an emergency; ii) from an inpatient team as an urgent referral; iii) a return to theatre following an elective bariatric procedure; iv) another hospital via patient transfer to a specialised unit,with the intent to treat or diagnose complications of bariatric surgery