Overt gastrointestinal bleeding secondary to left inferior phrenic artery pseudoaneurysm postgastric bypass surgery.

Bleeding from a visceral artery pseudoaneurysm (VAPA) is a rare but significant complication of bariatric surgery. Patients may present with gastrointestinal (GI) haemorrhage in the forms of haematemesis, melaena, haematochezia or haemodynamic compromise. Although CT angiogram, endoscopy and laparoscopy form essential parts of diagnostic assessment, small pseudoaneurysms with intermittent bleeding may be overlooked. We report the case of a man in his 40s who presented to the emergency department with massive GI bleeding and subsequent haemodynamic instability, secondary to a pseudoaneurysm from a vascular injury during a recent bariatric procedure. This case highlights the diagnostic challenges of obscure, intermittent bleeding involving the bypassed stomach with unremarkable investigation findings, and aims to raise awareness among clinicians in considering the less common postgastric-bypass complications.