[Case of neuroleptic malignant syndrome following open heart surgery for thoracic aortic aneurysm with parkinson's disease].

An 80-year-old woman with Parkinson's disease was scheduled for open heart surgery to repair thoracic aortic aneurysm. Parkinson's symptoms were normally treated using oral levodopa (200 mg), selegiline-hydrochloride (5 mg), bromocriptine-mesilate (2 mg), and amantadine-hydrochloride (200 mg) daily. On the day before surgery, levodopa 50mg was infused intravenously. Another 25 mg of levodopa was infused immediately after surgery. Twenty hours later, the patient developed tremors, heyperventilation, but no obvious muscle rigidity. Two days after surgery, the patient exhibited high fever, hydropoiesis, elevated creatine kinase, and a rise in blood leukocytes. She was diagnosed with neuroleptic malignant syndrome. She was intubated, and received dantrolene sodium. Symptoms of neuroleptic malignant syndrome disappeared on the fourth postoperative day. The stress of open heart surgery, specifically extracorporeal circulation and concomitant dilution of levodopa, triggered neuroleptic malignant syndrome in this patient. Parkinson's patients require higher doses of levodopa prior to surgery to compensate and prevent neuroleptic malignant syndrome after surgery.