DSA vs. BIS for Anesthesia and Analgesia Management (DSA-PRECISION)

Density Spectral Array Provides Intraoperative Precision Anesthesia and Analgesia Management; A Prospective Observational Study

The purpose of this study is to compare two different methods of monitoring brain activity (anesthesia depth) during gynecological surgeries.

When patients undergo surgery under general anesthesia, doctors use monitors to ensure they are at the right level of sleep and pain relief. Traditionally, a method called the Bispectral Index (BIS) is used, which provides a single number to represent brain activity. A newer method, called Density Spectral Array (DSA), provides a more detailed, color-coded map of brain waves in real-time.

Researchers want to see if using the more detailed DSA map helps anesthesiologists adjust medication more precisely. The study will compare the total amount of anesthetic and pain-relief drugs used in patients monitored with DSA versus those monitored with BIS. The goal is to determine if DSA leads to more personalized care, potentially reducing drug use and improving recovery after surgery

Study Overview

• Status: Completed
• Conditions: Anesthesia, General; Intraoperative Monitoring; Gynecologic Surgical Procedures; Anesthesia Depth Monitoring
• Intervention / Treatment: Device: Density Spectral Array (DSA) Monitoring; Device: Bispectral Index (BIS) Monitoring

Detailed Description

This prospective observational study will include 45 patients undergoing elective gynecological oncology surgery under general anesthesia. Patients will be monitored using standard anesthesia monitoring (Pulse oximetry, non-invasive blood pressure, ECG, and ETCO2) along with brain activity monitoring.

The anesthesia management will follow a Total Intravenous Anesthesia (TIVA) protocol consisting of propofol, remifentanil, and lidocaine. Patients will be divided into two groups based on the anesthesiologist's preference for monitoring anesthesia depth: the Bispectral Index (BIS) group and the Density Spectral Array (DSA) group.

Hemodynamic parameters (heart rate, blood pressure), BIS values, and DSA images will be recorded at specific intervals: before induction, after induction, at the start of surgery, every 30 minutes during the procedure, at the end of surgery, and after extubation. The total amounts of propofol and remifentanil used during the operation will be documented for each patient.

In the postoperative period, patients will be monitored in the recovery unit at the 15th, 30th, and 60th minutes. Visual Analog Scale (VAS) scores for pain, additional analgesic requirements, and hemodynamic parameters will be recorded. Once orientation and cooperation are established, patients will also be evaluated for any signs of intraoperative awareness

• Study Type: Observational
• Enrollment (Actual): 45

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Ankara, Turkey (Türkiye), 06
    • Dr. Abdurrahman Yurtaslan Oncology Training and Research Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study population consists of female patients aged 18-65 years, with an ASA physical status of I-III, who are scheduled for elective gynecological oncology surgery under general anesthesia at a single tertiary oncology center. Participants are selected from patients who meet the inclusion criteria and do not require premedication, ensuring a standardized group for monitoring anesthesia depth and drug consumption.

Description

Inclusion Criteria:

• Aged between 18 and 65 years
• ASA physical status I-III
• Patients scheduled for elective gynecological oncology surgery
• Body mass index (BMI) ≤ 35 kg/m²
• Able to provide voluntary informed consent
• Patients who do not require premedication

Exclusion Criteria:

• Allergy or hypersensitivity to propofol, opioids, or lidocaine
• Liver failure or kidney failure
• Previous adjuvant chemotherapy
• Emergency surgery
• Operations lasting longer than 3 hours
• Neurological diseases such as epilepsy, Alzheimer's disease, or dementia
• Cerebrovascular disease or known brain lesions
• Heart conduction disorders such as high-degree atrioventricular block
• Patients requiring premedication
• History of chronic pain
• Chronic opioid use
• Diabetes mellitus with neuropathy
• Patients unable to establish cooperation

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
DSA Group (Density Spectral Array); Patients in this group will have their anesthesia depth monitored and managed using Density Spectral Array (DSA) in addition to standard monitoring. Anesthesia will be maintained using a Total Intravenous Anesthesia (TIVA) protocol with propofol, remifentanil, and lidocaine. The anesthesiologist will adjust the drug infusion rates based on real-time color-coded brain wave maps provided by the DSA to maintain an optimal level of anesthesia and analgesia.	Device: Density Spectral Array (DSA) Monitoring; Anesthesia depth and analgesia will be managed using real-time color-coded EEG power spectrum analysis (Density Spectral Array). The anesthesiologist will adjust the infusion rates of propofol and remifentanil based on the visual representation of brain wave frequencies and power distribution. This method allows for a more detailed and individualized assessment of the patient's response to anesthetic and analgesic agents compared to numerical indices alone.
BIS Group (Bispectral Index); Patients in this group will have their anesthesia depth monitored and managed using the Bispectral Index (BIS) in addition to standard monitoring. Anesthesia will be maintained using a Total Intravenous Anesthesia (TIVA) protocol with propofol, remifentanil, and lidocaine. The anesthesiologist will adjust the drug infusion rates based on the numerical BIS values (target range 40-60) to maintain an optimal level of anesthesia and analgesia.	Device: Bispectral Index (BIS) Monitoring; Anesthesia depth will be managed using the processed EEG numerical index (Bispectral Index). The anesthesiologist will adjust the infusion rates of propofol and remifentanil to maintain a target BIS value between 40 and 60. This represents the standard clinical practice for monitoring the hypnotic component of general anesthesia using a simplified numerical scale from 0 to 100.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Amount of Propofol Consumption	The total amount of propofol (in milligrams) administered to the patient during the entire surgical procedure to maintain the target anesthesia depth. The study compares whether monitoring with Density Spectral Array (DSA) leads to a significant reduction in total propofol consumption compared to Bispectral Index (BIS) monitoring.	From the start of anesthesia induction until the end of the surgical procedure (approximately 1 to 3 hours).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Amount of Remifentanil Consumption	The total amount of remifentanil (in micrograms) administered to the patient during the entire surgical procedure to maintain the target analgesia level. The study compares whether monitoring with Density Spectral Array (DSA) leads to a significant reduction in total remifentanil consumption compared to Bispectral Index (BIS) monitoring.	From the start of anesthesia induction until the end of the surgical procedure (approximately 1 to 3 hours).
Postoperative Pain Scores (Visual Analog Scale - VAS)	Assessment of postoperative pain using the Visual Analog Scale (VAS), where 0 represents no pain and 10 represents the worst possible pain. The scores will be recorded to evaluate the quality of postoperative analgesia between the two groups.	At the 15th, 30th, and 60th minutes in the post-anesthesia care unit (PACU).
Postoperative Rescue Analgesic Requirement	The total amount and frequency of additional (rescue) analgesic medications required by the patient in the recovery unit. This measure evaluates whether the intraoperative anesthesia management with Density Spectral Array (DSA) reduces the need for extra pain relief compared to Bispectral Index (BIS) monitoring.	During the first 60 minutes in the post-anesthesia care unit (PACU).

Collaborators and Investigators

• Sponsor: Dr Abdurrahman Yurtaslan Ankara Oncology Training and Research Hospital

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2025
• Primary Completion (Actual): December 31, 2025
• Study Completion (Actual): March 1, 2026

Study Registration Dates

• First Submitted: March 25, 2026
• First Submitted That Met QC Criteria: March 25, 2026
• First Posted (Actual): March 30, 2026

Study Record Updates

• Last Update Posted (Actual): April 6, 2026
• Last Update Submitted That Met QC Criteria: March 31, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: hypnosis; nociception; eeg; dsa
• Other Study ID Numbers: 2025-03/51; AbdurrahmanYAOTRH (Other Identifier: Dr. Abdurrahman Yurtaslan Ankara Oncology Training and Research Hospital)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data (IPD) will not be shared to ensure patient confidentiality and data privacy, as per the institutional ethics committee guidelines. The study results will be disseminated through peer-reviewed publications and conference presentations in an aggregated format, ensuring that no individual patient can be identified.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No