ANI and Remifentanil in Skull Pin Fixation.

Kaohsiung Medical University Chung-Ho Memorial Hospital27 enrolled

Overview

Forty patients were enrolled, and all patients used total intravenous anesthesia (remifentanil-propofol based total intravenous analgesia) as anesthesia induction and maintenance. According to the preliminary data of this department, patients who underwent intracranial surgery for skull pin fixation used remifentanil 5.0-6.0 ng/ml, while the hemodynamics is relatively stable. Therefore, when this plan is implemented, the patient needs to be under the same depth of anesthesia (monitored by electroencephalography, maintaining a value of 40-60), first start with remifentanil 6.0 ng/ml, and use the up and down method as adjust 0.5 ng/ml of concentration of remifentanil each time. An Analgesia Nociception Index(ANI) lower than 30 and hyperdynamics (the increased heart rate(HR) and mean blood pressure(MBP) up 20% of baseline or HR\>100bpm and arterial blood pressure(ABP)\>180/100mmHg) indicates insufficient analgesia, therefore increase it by 0.5 ng/ml; an ANI higher than 30 and stable hemodynamics (the changes of HR and MBP within 20% of baseline or HR\<50bpm and ABP\<90/50mmHg) indicates that analgesia is acceptable, and the next patient will decrease it by 0.5 ng/ml during skull pin fixation. Data collection: Heart Rate, Measure blood pressure, Analgesia Nociception Index, Bispectral index, concentrations of propofol and remifentanil before 2 mins, during, 5, and 15 mins of skull pin fixation were recorded and analyzed.

Study Type

INTERVENTIONAL

Allocation

Purpose

PREVENTION

Masking

NONE

Enrollment

Conditions

Pain, Procedural

Interventions

RemifentanilDRUG

First start with remifentanil 6.0 ng/ml, and use the up and down method as adjust 0.5 ng/ml of concentration of remifentanil each time. An ANI lower than 30 and hyperdynamics (the increased heart rate and mean blood pressure up 20% of baseline or heart rate\>100bpm and arterial blood pressure\>180/100mmHg) indicates insufficient analgesia, therefore increase it by 0.5 ng/ml; an ANI higher than 30 and stable hemodynamics (the changes of HR and MBP within 20% of baseline or HR\<50bpm and ABP\<90/50mmHg) indicates that analgesia is acceptable, and the next patient will decrease it by 0.5 ng/ml during skull pin fixation.

Eligibility

Sex: ALLMin age: 20 YearsMax age: 80 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Must be at least 20 years old and less than 80 years old 2. With anesthesia risk grade below grade three (including grade three) (ASA I\~III) 3. Patients who are expected to undergo intracranial surgery for skull pin fixation Exclusion Criteria: 1. Those with anesthesia risk classification ASA class IV or higher 2. Those who are allergic to opioid analgesics or propofol drugs 3. Emergency patients

Outcomes

Primary Outcomes

50% effect concentration of remifentanil

50% effect concentration of remifentanil will be recorded at 2 mins before fixation, during fixation, 5mins after fixation, and 15 mins after fixation.

Time frame: peri-fixation period

90% effect concentration of remifentanil

90% effect concentration of remifentanil will be recorded at 2 mins before fixation, during fixation, 5mins after fixation, and 15 mins after fixation.