Efficacy of propofol in controlling myoclonus during rewarming in a brain hypothermia patient

Propofol is an intravenous anaesthetic agent having anticonvulsant property. We report here a case in which propofol was effective in controlling myoclonus during rewarming in brain hypothermia patient. A 35-year-old male patient was admitted in a comatose state with right-sided hemiparesis, anisocoria and absence of bilateral light reflex. On admission, a head CT showed traumatic subarachnoid hemorrhage, left subdural hematoma, 10 mm midline shift and tentorial herniation with massive brain swelling together with extensive hypodensity in the frontal, temporal and occipital lobes bilaterally. Left decompressive hemicraniectomy, removal of hematoma and brain hypothermia therapy were started immediately. Postoperative head CT showed 15 mm midline shift. The temperature of the jugular bulb was maintained at 34 degrees C for 2 days together with sedation using midazolam under artificial ventilation. The patient was gradually rewarmed at a rate of 0.5 degree C per day from the third hospital day. Myoclonus of sudden onset developed on the patient's head and upper extremities on the third hospital day. An intravenous bolus injection of 10 mg midazolam and continued intravenous infusion of midazolam were given but they did not completely stop myoclonus. A bolus of propofol 60 mg was given intravenously and continuous intravenous infusion of propofol 2 mg.kg-1.hr-1 was started after which the progression of myoclonus disappeared. Myoclonus was kept controlled until the continuous intravenous infusion of midazolam and propofol was discontinued on the sixth hospital day, after which myoclonus occurred again after extubation on the seventh hospital day. The clinical course of this case suggests that propofol might be an alternative effective agent to suppress refractory myoclonus.