BIS Variability and Change in Quality of Recovery After Surgery

NCT07454629 | Recruiting

• 1 other identifier: SEAH-BISVARIABILITY-2026
• Study Type: observational
• Target: 126
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective observational study aims to examine the relationship between fluctuations in anesthesia depth, measured by bispectral index (BIS) monitoring during surgery, and changes in patients' postoperative recovery quality. BIS monitoring is routinely used during general anesthesia to assess the depth of anesthesia, but BIS values often fluctuate over time rather than remaining stable. The clinical significance of this variability is not well understood. In this study, BIS variability during anesthesia induction and maintenance will be evaluated and compared with changes in postoperative recovery quality. Recovery quality will be assessed using the Quality of Recovery-15 (QoR-15) questionnaire, which will be administered before surgery and again on the first postoperative day. The primary outcome of the study will be the change in QoR-15 score from the preoperative baseline to postoperative day one (ΔQoR-15). Delirium screening and routine perioperative clinical data will also be collected. No additional interventions beyond standard anesthesia care will be performed. The results of this study may help improve understanding of how intraoperative anesthesia stability relates to patient recovery after surgery.

Conditions

Cholecystectomy, Laparoscopic; Bispectral Index Variability During General Anesthesia and Postoperative Recovery

Keywords

Bispectral Index; Anesthesia Depth; Quality of Recovery; General Anesthesia; Postoperative Recovery; Bispectral Index Variability

Outcome Measures

Primary Outcomes (1)

• Change in Quality of Recovery-15 (ΔQoR-15) Score

  The primary outcome is the change in postoperative recovery quality measured using the Quality of Recovery-15 (QoR-15) questionnaire. ΔQoR-15 is defined as the difference between the postoperative day one QoR-15 total score and the preoperative baseline QoR-15 total score. The QoR-15 is a validated 15-item questionnaire with total scores ranging from 0 to 150 points, where higher scores indicate better recovery quality. ΔQoR-15 will be analyzed as a continuous variable (points).

  From preoperative baseline to postoperative day one

Secondary Outcomes (2)

• Incidence of Postoperative Delirium (Nu-DESC ≥ 2)

  From preoperative baseline to early postoperative recovery in the post-anesthesia care unit (PACU), within the first 2 hours after anesthesia

• Postoperative Pain Intensity (VAS)

  Postoperative day 1

Study Arms (1)

Elective Laporoscopic Cholecystectomy Patients Undergoing General Anesthesia

This cohort consists of adult patients undergoing elective laparoscopic cholecystectomy under general anesthesia. All participants will receive routine anesthetic management according to standard clinical practice. No experimental intervention or protocol-driven modification of anesthesia care will be applied. Intraoperative bispectral index (BIS) monitoring will be used as part of standard anesthesia monitoring. BIS data and routine perioperative clinical variables will be recorded for observational analysis. Postoperative recovery will be assessed using validated questionnaires administered before surgery and on postoperative day one. The study involves a single observational cohort without a comparison or control group.

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adult patients aged 18 to 65 years undergoing elective laparoscopic cholecystectomy under general anesthesia. All participants will receive routine perioperative care according to standard clinical practice, including intraoperative bispectral index (BIS) monitoring. The study includes a single prospective observational cohort, and no experimental intervention or alteration of standard anesthesia management will be performed. Participants will be assessed preoperatively and postoperatively to evaluate changes in recovery quality following surgery.

You may qualify if:

• Adults aged 18 to 65 years
• Scheduled for elective laparoscopic cholecystectomy
• American Society of Anesthesiologists (ASA) physical status I-III
• Planned general anesthesia with routine bispectral index (BIS) monitoring
• Ability to provide written informed consent

You may not qualify if:

• History of neurological disease
• Use of neuropsychiatric medications
• Cognitive impairment or mental retardation
• Inability to complete the Quality of Recovery-15 (QoR-15) questionnaire

Sponsors & Collaborators

• Sakarya University: lead

Study Sites (1)

Sakarya University Training and Research Hospital, Department of Anesthesiology and Reanimation

Sakarya, Serdivan, 54000, Turkey (Türkiye)

RECRUITING

Study Officials

• Ayça Taş Tuna, Professor, M.D.

  Sakarya University Faculty of Medicine

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Ahmet R Doğan, M.D

CONTACT

+905427988070; a.ridvandogan@gmail.com

Ayça Taş Tuna, Prof. Dr

CONTACT

+90 532 300 48 26; aycatas@yahoo.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Prof.Dr.

Study Record Dates

• First Submitted: February 18, 2026
• First Posted: March 6, 2026
• Study Start: January 1, 2026
• Primary Completion (Estimated): May 1, 2026
• Study Completion (Estimated): December 30, 2026
• Last Updated: April 8, 2026

Record last verified: 2026-04

Locations

TU (1)