Unanticipated intraoperative haemodynamic challenges during adrenalectomy for a phaeochromocytoma misdiagnosed as an adrenocortical tumour.

A hypertensive woman in her mid-30s presented with flank pain probably secondary to a left adrenal mass. Biochemical evaluation, including serum cortisol, dehydroepiandrosterone and 24-hour urinary metanephrines, was negative, and the mass was diagnosed as a non-functioning adrenocortical tumour. Intraoperatively, tumour manipulation precipitated abrupt hypertensive surges with bradycardia, necessitating nitroglycerine and sodium nitroprusside infusion. Following adrenal vein ligation, profound hypotension ensued, requiring transient noradrenaline infusion to maintain adequate mean arterial pressure. Histopathology confirmed phaeochromocytoma, with positive synaptophysin and chromogranin A staining. This case underscores the potential for biochemically and clinically silent phaeochromocytomas and explores possible reasons for false-negative biochemical results. Intraoperative haemodynamic instability during adrenal manipulation should raise suspicion of catecholamine secretion, even in the absence of classical symptoms. The report emphasises the importance of invasive monitoring and anaesthetic preparedness to manage unexpected catecholamine release.