An obese, 65 years old woman admitted to the department of orthopedics for total knee replacement arthroplasty under the diagnosis of severe degenerative arthritis and pain of both knee joints. Incidentally, an asymptomatic huge hepatic cyst (size 25 x 27 cm) was found in the pre-operative check ups During the induction of general anesthesia, severe hypotension and intractable atrial fibrillation with RVR suddenly developed. Initially, various tilting positions together with rapid fluid replacement were tried immediately considering the clinical features as supine hypotensive episode, but with little improvement of clinical situation. Then, a bolus of intravenous hydrocortisone succinate 100 mg was tried empirically, resulting in the immediate normalization of blood pressure. Her laboratory findings after the incidence showed decreased blood cortisol level, but ACTH stimulation test was within normal limits. We concluded the case, clinically, as functional adrenal insufficiency and report the case with the reviews of related articles