This clinical trial aims to find a better drug concentration of Remifentanil in Uterine Fibroid Ablation. The main question it seeks to answer is:
\[primary hypothesis 1\] Remifentanil concentration of 2.0 ng/mL provides better pain control in Uterine Fibroid Ablation.
There is a comparison group in this study: Researchers will compare Remifentanil concentration of 1.0 ng/mL to see if provides similar pain control with fewer side effects.
Participants will be separated into two groups, one group with a Remifentanil concentration of 2.0 ng/mL and the other 1.0 ng/mL. During uterine fibroid ablation, the patient\'s pain index will be recorded (using a Visual Analogue Scale (VAS) of 0\~10 points). We will also record vital signs during the procedure.