Successful management of unsuspected retroperitoneal paraganglioma via the use of combined epidural and general anesthesia: a case report

INTRODUCTION Similar to pheochromocytomas, paragangliomas can secrete catecholamines, although they are usually non-functional and clinical presentation is non-specific. We present a case of accidental, intra-operatively diagnosed neuroendocrine-active sympathetic paraganglioma, which was suspected and confirmed during elective retroperitoneal tumor removal. CASE PRESENTATION A 25-year-old Caucasian Croatian man, American Society of Anesthesiologists status 1, underwent elective surgery for retroperitoneal tumor removal. The tumor had been discovered by chance during a routine examination and was suspected to be a sarcoma. Our patient had no history of previous medical conditions nor did he have symptoms characteristic of a neuroendocrine secreting tumor. The results of ultrasound and magnetic resonance imaging studies showed a large, well demarcated retroperitoneal tumor mass in his upper abdomen localized between the aorta and vena cava, measuring approximately 9×6×4.5cm. In the operating room an epidural catheter was inserted at the T7 to T8 level prior to induction of general anesthesia. Epidural analgesia was maintained by an infusion pump with local anesthetic and opiate mixture. During the surgical excision of the tumor, hemodynamic changes occurred, with hypertension (205/110mmHg) and tachycardia (up to 120 beats/minute). In spite of the fact that the surgical field of work did not include adrenal glands whose direct manipulation could explain this occurrence, there was a high degree of suspicion for the presence of a neurosecreting tumor. His clinical symptoms were relieved after administration of urapidil, esmolol and magnesium sulfate. After tumor excision, our patient developed severe hypotension. Hemodynamic stability was reinstated with aggressive volume replacement, with crystalloids and colloids, vasopressors and hydrocortisone. His post-operative course was unremarkable and on the eighth post-operative day our patient was discharged from hospital, with no consequences or symptoms on follow-up two years after surgery. CONCLUSIONS Our patient's case emphasizes the need to consider the presence of extra-adrenal paragangliomas in the differential diagnosis of retroperitoneal tumors, despite their rare occurrence. In our patient's case, invasive hemodynamic monitoring during combined general anesthesia and epidural analgesia and early recognition of catechol-induced symptoms raised suspicion of the existence of a paraganglioma, and this led to an adequate therapeutic approach and favorable outcome of the surgery. Pre-operative recognition of paragangliomas could lead to better pre-operative preparation, but even high clinical suspicion in undiagnosed forms during surgery and the availability of rapid and short-acting vasodilatators, α-blockers and β-blockers might favor good outcome.