Evaluation of Response to Pain From Skull Pin Fixation in Craniotomies

Not yet recruiting

• Conditions: Electroencephalography; Craniotomy Surgery; Pain Management
• Interventions: Procedure: Scalp nerve block; Drug: Opioid Anesthetics; Procedure: Local Anesthetic Injection

• Registration Number: NCT06811701
• Lead Sponsor: Diskapi Teaching and Research Hospital

Brief Summary

The goal of this observational study is to investigate the relationship between the response to skull pin fixation pain and the analysis of blood pressure, heart rate, and brain wave activity in adults undergoing brain surgery. The main questions it aims to answer are:

Does the analysis of blood pressure, heart rate, and brain wave activity indicate the patient's response to skull pin fixation pain during brain surgery? How do the methods used to reduce skull pin fixation pain in brain surgeries affect narcotic opioid consumption? The researchers will monitor the patients' response to skull pin fixation pain during surgery through the analysis of brain wave activity.

Detailed Description

Patients with an ASA (American Society of Anesthesiologists) score of I-II who are undergoing elective craniotomy under general anesthesia with the use of a skull clamp will be included in the study. The methods used to manage patients' pin-related pain will be recorded on the follow-up form: 1-intravenous opioids, 2- local anesthetic (LA) injection at the pin site, and 3- scalp block. The patients' hemodynamic responses and their reactions to painful stimuli, as recorded by the BIS-DSA monitor, will be documented during the placement of the skull clamp. These records are automatically archived in the BIS-DSA device. Waveform analyses from the BIS-DSA will later be converted into numerical values using the "Hue formula."

Study Timeline

• Study First Submitted: 2025-01-28
• Status Verified: 2025-02
• Study First Submitted QC: 2025-02-05
• Last Update Submitted: 2025-02-05
• Study First Posted: 2025-02-06
• Last Update Posted: 2025-02-06
• Study Start: 2025-02-28
• Primary Completion: 2025-04-30
• Study Completion: 2025-05-30

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 120

Inclusion Criteria

• Adult patients aged 18-70 years undergoing elective craniotomy.
• Patients classified as ASA I-II according to the American Society of Anesthesiologists (ASA) classification.
• Patients scheduled for surgery under general anesthesia.
• Patients who provide written informed consent to participate in the study.
• Patients with normal cognitive function (i.e., no diagnosed dementia or severe cognitive impairment).
• Patients with a preoperative BIS value within the normal range (i.e., no extreme baseline deviations).

Exclusion Criteria

• Patients classified as ASA III or higher.
• Patients with neurological disorders (e.g., Parkinson's disease, epilepsy, stroke history).
• Patients with psychiatric disorders (e.g., severe depression, schizophrenia) that may affect pain perception and response.
• Patients with known allergies to local anesthetics or opioids.
• Pregnant or breastfeeding women.
• Patients with contraindications to anesthesia, including but not limited to:
• Severe cardiovascular disease (e.g., uncontrolled hypertension, recent myocardial infarction).
• Severe respiratory disease (e.g., COPD, uncontrolled asthma).
• Patients with any neurological or pharmacological condition that may interfere with BIS-DSA or EEG measurements.
• Patients with preoperative chronic opioid use (≥3 months) due to potential tolerance affecting response to intraoperative analgesia.
• Patients with a history of substance abuse that may alter the BIS response or anesthetic metabolism.
• Patients with significant hearing or communication impairments, preventing them from understanding or responding to preoperative assessments.
• Patients with significant scalp pathology (e.g., infections, scars, large vascular malformations) at the BIS electrode placement site, which may interfere with signal acquisition.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Group 1: Scalp group	Scalp nerve block	"This group consists of patients who receive a scalp nerve block for pain management during skull pin fixation."
Group 2: Opioid Group	Opioid Anesthetics	"This group consists of patients who receive intravenous opioids for pain management during skull pin fixation."
Group 3: Local Anesthetic Group	Local Anesthetic Injection	"This group consists of patients who receive a local anesthetic injection at the pin site before skull pin fixation."

Primary Outcome Measures

Name	Time	Method
Changes in BIS-DSA spectral analysis before and after skull pin fixation	From baseline (before skull pin fixation) to 5 minutes after skull pin fixation.	The primary outcome measure will be the changes in brain wave activity, specifically in the BIS-DSA spectral analysis, before and after skull pin fixation. This will be assessed by comparing the pre- and post-fixation BIS values and spectral features such as alpha dropout, beta arousal, and delta changes

Secondary Outcome Measures

Name	Time	Method
Changes in Mean Arterial Pressure (MAP) before and after skull pin fixation	Baseline to 5 minutes after skull pin fixation.	Hemodynamic response will be evaluated by measuring changes in mean arterial pressure before and after skull pin fixation.