Effects of Sevoflurane vs Desflurane on Early Recovery and Cognitive Function in Elderly Patients Undergoing Scheduled Non-Cardiac Surgery

Delayed emergence from anesthesia and early postoperative cognitive decline represent important clinical challenges in elderly surgical patients, who commonly exhibit reduced physiological reserve, altered pharmacodynamics, and multiple comorbidities. The combination of age-related organ changes, diminished drug clearance, and increased sensitivity of the central nervous system places this population at heightened risk of prolonged awakening, impaired reflexes, and postoperative disorientation. Volatile anesthetics such as sevoflurane and desflurane are widely used in geriatric anesthesia owing to their low blood/gas solubility and generally favorable recovery profiles, yet their comparative impact on early emergence and cognitive recovery remains insufficiently established. This prospective randomized single-blind trial is therefore designed to compare desflurane with sevoflurane in elderly patients undergoing elective non-cardiac surgery, with the objective of determining whether desflurane's lower blood/gas partition coefficient translates into clinically meaningful improvements in postoperative recovery.

Conditions Conditions: Postoperative Delayed Emergence and Early Cognitive Decline in Elderly Surgical Patients Keywords: general anesthesia, elderly, desflurane; sevoflurane; recovery, cognition. Study Design Study Type: Interventional. The perioperative protocol begins with standard patient preparation, including verification of the pre-anesthesia checklist and initiation of monitoring with ECG, pulse oximetry, non-invasive blood pressure, and capnography. Three baseline hemodynamic readings are recorded to establish reference values. Two peripheral IV lines (18-20G) are inserted for fluids and medication administration. Patients underwent a baseline Short Orientation Memory Concentration Test (SOMCT). Anesthesia induction is standardized with Fentanyl: 2 µg/kg, Propofol: titrated to loss of consciousness, Cisatracurium: 0.15 mg/kg to facilitate intubation. Endotracheal intubation is confirmed by capnography. Patients are randomized into two groups:

Group D - Desflurane, Group S - Sevoflurane, maintenance protocol under controlled ventilation targeting ETCO₂ between 30 and 40 mmHg. Volatile agents are discontinued at the end of surgery, and emergence parameters-including time to eye opening, response to verbal commands, and extubation-were recorded by a blinded observer. In the post-anesthesia care unit, recovery is assessed using the modified Aldrete Score (MAS) until ≥9 and SOMCT until ≥20, and discharge times are documented. Hemodynamic, respiratory, and anesthetic variables are continuously monitored throughout the procedure. Statistical Analysis: Data entry and analysis will be performed using SPSS software (version 25.0). Descriptive Analysis: Normally distributed continuous quantitative variables will be summarized as mean ± standard deviation. Non-normally distributed continuous variables will be reported as median and interquartile range [IQR: 25%-75%]. Categorical variables will be presented as absolute frequencies (n) and relative frequencies (%). Analytical Analysis: Associations between two categorical variables will be assessed using Pearson's chi-square test when conditions are met; otherwise, Fisher's exact test will be applied. For comparisons between a categorical and a normally distributed quantitative variable, Student's t-test will be used, while the Mann-Whitney U test will be employed for non-parametric data. A significance level of p < 0.05 will be considered statistically significant. In multivariate analysis, risk estimates will be expressed as odds ratios (OR) with 95% confidence intervals (95% CI).

Inclusion criteria

• Elderly patients whose ages are superior to 60 years of age [1].
• Patients with an American Society of Anesthesiologists Classification (ASA) I, II or III stable (Annex 1).
• Patients undergoing elective non-cardiac surgery under general anesthesia with tracheal intubation.

Non-inclusion criteria:

• Patients having declined to participate in the study protocol.
• Patients with a contraindication for minimal flow anesthesia such as hyperthermia, smoke intoxication and ketoacidosis metabolic condition (for example, anorexia nervosa).
• Patients with history of malignant hyperthermia.
• Patients with Psychotic disorders.
• Patients with substance abuse.
• Patients with severe obstructive or restrictive pulmonary disease.
• Patients with hepatic disease.
• Patients with end stage renal disease.
• Patients with history of allergy to study drugs.

Exclusion criteria

• We excluded from our study patients who presented with perioperative complication or instability requiring ICU transfer due to extubation failure.