[Changes of blood volume and blood propofol concentration during the anesthetic management of a pheochromocytoma patient].

A 44-year-old man with right pheochromocytoma was scheduled for tumor resection. General anesthesia was maintained with nitrous oxide (66%), oxygen (33%), continuous infusion of propofol (4 mg.kg-1.hr-1), and continuous epidural block (1.5% mepivacaine 4 ml.hr-1). During operation, cardiac output and blood volume (BV) were measured by pulse dye-densitometry using DDG-2001 (Nihon Kohden, Japan), and arterial and mixed venous blood concentrations of propofol were measured by high performance liquid chromatography (HPLC). After tumor resection, cardiac output increased without change in BV, on the other hand, both arterial and mixed venous blood propofol concentrations clearly decreased. In conclusion, during the anesthetic management with propofol in case of pheochromocytoma, attention should be paid to depth of anesthesia because of changing propofol blood concentration.