Please assess the completion status of the following clinical trial:

Trial Title: The EC90 of Remifentanil Blunting Hemodynamic Changes to Head Fixation

Study Design Characteristics:
- Allocation: None
- Intervention Model: SINGLE_GROUP
- Observational Model: None
- Primary Purpose: PREVENTION
- Time Perspective: None
- Masking: NONE
- Phase: None
- Number of Arms: 1.0

Eligibility Criteria:
Inclusion Criteria:~* patients undergoing neurosurgery that require head fixation with mayfield head holder~* patients who agree to our study~Exclusion Criteria:~* patients who don't agree to our study~* BMI\<16.0 or BMI\>30~* cardiovascular disease, pulmonary disease, renal disease~* alcoholic abuser or drug abuser~* patients who takes any drug having an influence on cardiovascular system or sympathetic nervous system~* any use of local anesthetics or drugs which have an influence on cardiovascular system from beginning of induction to peri-fixation period

- Gender: ALL
- Minimum Age: 20 Years
- Maximum Age: 65 Years
- Healthy Volunteers: f

Study Arms:
- neurosurgery with fixation (Type: EXPERIMENTAL): None

Based on this trial design, predict the completion outcome and termination type (if applicable).