Adiposity and Immunometabolism in Sepsis

Obesity has been shown to increase adverse outcomes in some critically ill patients e.g. those with COVID-19. For patients with sepsis this association is less clear cut but there is evidence that body fat distribution, resulting from impaired subcutaneous adipose tissue function, is associated with adverse clinical outcomes in critical care. The investigators aim to study subcutaneous adipose tissue function in lean and obese sepsis patients in critical care and compare that to healthy controls. First, the study will investigate differences in adipose tissue function (inflammation and mitochondrial function) related to obesity. Second, the investigators will examine whether lean critically ill patients with sepsis have enhanced adipose tissue inflammation and mitochondrial dysfunction compared to lean controls and whether this is further exacerbated by obesity. Patients will be either undergoing emergency abdominal surgery, or will have been admitted to a critical care unit with a diagnosis of sepsis. The investigators will collect blood and adipose tissue biopsies from the patients, and these will be analysed for markers of inflammation and of mitochondrial function. The aim is to better understand the relationship between obesity, inflammation, mitochondrial dysfunction and sepsis. The investigators hope that this may improve the understanding of the pathophysiology of sepsis and allow more targeted interventions for patients based on differences in their baseline metabolic state.