tokens: METHODS : Following induction of anesthesia by fentanyl ( 0 . 15 mg kg ( - 1 ) ) and propofol ( 2 . 0 mg kg ( - 1 ) ) , 13 patients received phenylephrine ( 0 . 1 mg iv ) and 12 patients received ephedrine ( 10 mg iv ) to restore mean arterial pressure ( MAP ) .