Effect of Propofol, Sevoflurane and Isoflurane on Postoperative Cognitive Function Following Laparoscopic Cholecystectomy in Elderly Patients

Postoperative cognitive dysfunction (POCD) is characterized by impairment of memory, attention, and executive functions following surgery and anesthesia, particularly in elderly patients. With increasing life expectancy and a growing elderly population undergoing surgery, POCD has emerged as an important perioperative concern.

Elderly patients are more vulnerable to cognitive decline due to reduced neuronal reserve, age-related cerebral changes, and altered pharmacodynamics of anesthetic agents. Laparoscopic cholecystectomy, though minimally invasive, still involves general anesthesia and pneumoperitoneum, which can affect cerebral perfusion and cognitive outcomes.

Among commonly used anesthetic agents, propofol, sevoflurane, and isoflurane differ in their mechanisms of action, cerebral metabolic effects, and neuroinflammatory responses. This study was undertaken to compare their impact on postoperative cognitive function in elderly patients undergoing laparoscopic cholecystectomy.

Study Design and Setting

A prospective, randomized, comparative study conducted at a tertiary care teaching hospital after approval from the Institutional Ethics Committee.

Study Population

Elderly patients aged ≥60 years scheduled for elective laparoscopic cholecystectomy.

Inclusion Criteria

Age ≥60 years

ASA physical status I–III

MMSE score ≥24 preoperatively

Written informed consent

Exclusion Criteria

Pre-existing cognitive impairment or psychiatric illness

History of stroke or neurodegenerative disease

Alcohol or drug abuse

Conversion to open surgery

Intraoperative complications or prolonged surgery (>2 hours)

Randomization and Group Allocation

Patients were randomized into three equal groups:

Group P: Propofol-based total intravenous anesthesia

Group S: Sevoflurane-based inhalational anesthesia

Group I: Isoflurane-based inhalational anesthesia

Anesthetic Technique

Standard monitoring (ECG, NIBP, SpO₂, EtCO₂)

Induction with fentanyl and muscle relaxant

Maintenance with assigned anesthetic agent

BIS monitoring maintained between 40–60

Standard postoperative analgesia

Cognitive Assessment

Cognitive function was assessed using the Mini-Mental State Examination (MMSE) at:

Preoperative baseline

6 hours postoperative

24 hours postoperative

72 hours postoperative

Statistical Analysis

Data were analyzed using SPSS software. Continuous variables were expressed as mean ± SD. Intergroup comparison was done using ANOVA, and p < 0.05 was considered statistically significant.

Demographic Profile

There were no statistically significant differences among the three groups in terms of age, gender distribution, ASA status, duration of surgery, or anesthesia.

Table 1. Demographic Characteristics

Values are expressed as mean ± standard deviation or number of patients. ASA = American Society of Anesthesiologists.

MMSE Scores

Table 2. Mean MMSE Scores at Different Time Intervals

Values are expressed as mean ± standard deviation. MMSE = Mini-Mental State Examination.

The decline was maximum in the isoflurane group (p < 0.05).

Recovery at 72 hours was complete in the propofol group, partial in sevoflurane, and incomplete in isoflurane group.

cerebral autoregulation.

Sevoflurane demonstrated intermediate effects. Although it provides rapid induction and emergence, studies suggest that volatile agents may increase amyloid beta aggregation and neuroinflammation, contributing to transient cognitive impairment.

Isoflurane showed the highest incidence and persistence of POCD. Isoflurane has been associated with increased neuronal apoptosis, calcium dysregulation, and enhanced inflammatory pathways, especially in aged brains.

Our findings are consistent with previous studies that report lower POCD incidence with propofol compared to volatile anesthetics. The results highlight the importance of anesthetic selection in elderly patients to minimize postoperative neurocognitive complications.

Limitations

Single-center study

Small sample size

Short follow-up duration

Use of MMSE alone may not detect subtle cognitive changes

Further multicentric studies with larger samples and long-term follow-up are recommended.

Propofol-based anesthesia provides superior cognitive outcomes compared to sevoflurane and isoflurane in elderly patients undergoing laparoscopic cholecystectomy. Isoflurane is associated with greater and prolonged postoperative cognitive dysfunction. Careful selection of anesthetic agents can significantly reduce POCD and improve postoperative recovery in elderly patients.