Effects of Low-Dose Ketamine Added to Propofol Sedation During Colonoscopy

The Effects of Adding Low-Dose Ketamine to Propofol Sedation on Bispectral Index Values, Hemodynamic Stability, and Recovery Time in Patients Undergoing Colonoscopy

"This prospective observational study aims to evaluate the effects of adding low-dose ketamine (0.25 mg/kg) to standard propofol sedation on hemodynamic stability, sedation depth, and recovery times in adult patients undergoing elective colonoscopy. Sedation depth will be objectively monitored using the Bispectral Index (BIS) alongside clinical scoring. The study observes and compares two standard sedation regimens routinely used in the clinic: propofol alone versus a combination of propofol and low-dose ketamine.

Researchers will record intraoperative hemodynamic parameters (mean arterial pressure, heart rate, oxygen saturation) and BIS values at regular intervals from baseline to the end of the procedure. Furthermore, postoperative recovery quality, cognitive function, and discharge readiness will be comprehensively assessed using the Modified Aldrete Score, Post Anesthetic Discharge Scoring System (PADSS), and a computerized Psychomotor Vigilance Test (PVT-B) at specific time points. The total amount of propofol consumed to maintain adequate sedation will also be compared between the two observational cohorts."

Inclusion Criteria:

• Patients scheduled for elective colonoscopy
• ASA physical status I-II

Exclusion Criteria:

• ASA physical status ≥ III
• Allergy to propofol or ketamine
• History of psychiatric illness
• Advanced cardiac disease
• Pregnancy
• Chronic use of opioids or sedatives
• Inability to cooperate
• Body Mass Index (BMI) > 35 kg/m^2