Modafinil Role in Preventing Postoperative Cognitive Dysfunction: A Randomized Clinical Trial in Sleeve Gastrectomy Patients Under General Anesthesia

Background: Postoperative cognitive dysfunction (POCD) is highly prevalent after bariatric surgery, particularly among patients with obesity. This study aims to assess whether single-dose preoperative modafinil enhances cognitive outcomes and prevents POCD in patients undergoing sleeve gastrectomy under general anesthesia. Methods: This randomized, double-blind trial included 80 adults scheduled for sleeve gastrectomy, who received either 200 mg oral modafinil or placebo before surgery. Cognitive and emotional function were evaluated using the Addenbrooke’s Cognitive Examination (ACE), Mini-Mental State Examination (MMSE), and Depression Anxiety Stress Scale (DASS-21), with Bonferroni-adjusted significance thresholds. Results: Baseline cognitive impairment was highly prevalent (80% ACE < 88; 26.25% MMSE < 27). Both groups demonstrated significant postoperative improvement in global ACE scores, verbal fluency, and memory (all p < 0.001), but not in attention or visuospatial domains. The language domain improved significantly only in the modafinil group ( p = 0.001). Critically, the modafinil group showed a 20% increase in patients achieving normal ACE scores and a 17.5% decrease in those with abnormal scores( p < 0.001), while changes in the placebo group were not significant. DASS-21 and MMSE scores remained stable, and adverse events were rare and mild. Conclusions: Sleeve gastrectomy led to robust cognitive improvement; single-dose modafinil provided categorical cognitive benefit but did not significantly impact global or emotional outcomes.