Electroencephalogram-guided anesthesia and postoperative anxiety and depression in elderly gastric cancer patients with sleep disorders

Abstract

BACKGROUND

Preoperative sleep disorders are common in elderly gastric cancer patients and may increase the risk of postoperative anxiety and depression. Traditional anesthesia depth monitoring relies on clinical signs, which may not accurately reflect the true anesthetic state in elderly patients. This study evaluates the effect of individualized anesthesia guided by electroencephalogram (EEG) monitoring on postoperative anxiety and depression symptoms in elderly gastric cancer patients with preoperative sleep disorders.

AIM

To determine whether EEG-guided anesthesia improves psychological recovery by stabilizing anesthesia depth in elderly gastric cancer patients with preoperative sleep disorders.

METHODS

This retrospective study included 240 patients aged ≥ 65 years with preoperative sleep disorders (Pittsburgh Sleep Quality Index ≥ 5) who underwent elective radical gastrectomy between January 2022 and December 2023. Patients were divided into an EEG monitoring group (n = 118) and a conventional monitoring group (control, n = 122). The EEG group used Bispectral Index (BIS) monitoring to adjust anesthetic dosage, maintaining BIS values between 40 and 60, while the control group relied on conventional clinical indicators for anesthesia depth adjustment. The primary outcomes were Hospital Anxiety and Depression Scale (HADS) scores at 3 days and 1 month postoperatively; secondary outcomes included postoperative delirium incidence, length of stay, and quality of life scores.

RESULTS

A total of 240 elderly gastric cancer patients with preoperative sleep disorders were included (118 EEG group, 122 control group) with well-matched baseline characteristics. EEG-guided anesthesia significantly reduced anesthetic drug consumption (propofol: 5.8 ± 1.2 mg/kg/hour vs 7.3 ± 1.4 mg/kg/hour, P < 0.001; remifentanil: 0.18 ± 0.04 μg/kg/minute vs 0.24 ± 0.05 μg/kg/minute, P < 0.001) and achieved 18.6% cost reduction. Primary outcomes showed the EEG group had significantly lower postoperative anxiety and depression scores at 3 days (HADS total: 11.8 ± 3.7 vs 15.9 ± 4.9, P < 0.001) and 1 month (8.7 ± 3.2 vs 13.2 ± 4.1, P < 0.001). The proportion of patients with clinically significant symptoms was reduced from 62.3% to 39.0% at 3 days and from 45.9% to 21.2% at 1 month (both P < 0.001). Multivariate analysis identified EEG-guided anesthesia as the strongest protective factor [odds ratio (OR) = 0.56, 95%CI: 0.41-0.78, P = 0.003], while poor sleep efficiency (OR = 2.24, P < 0.001) and frequent sleep disturbances (OR = 1.95, P = 0.001) were the most significant risk factors. Subgroup analysis revealed a dose-response relationship, with greatest benefits in patients with severe sleep disorders. BIS stability metrics strongly correlated with psychological outcomes (r = -0.462 for target range maintenance, P < 0.001). Secondary outcomes demonstrated significant improvements in the EEG group: (1) Lower complication rates (32.2% vs 48.4%, P = 0.010); (2) Reduced postoperative delirium (8.5% vs 17.2%, P = 0.038); and (3) Superior pain control, faster recovery, and shorter hospital stay (10.8 ± 2.7 days vs 12.5 ± 3.0 days, P < 0.001).

CONCLUSION

For elderly gastric cancer patients with preoperative sleep disorders, individualized anesthesia guided by EEG monitoring significantly reduces postoperative anxiety and depression symptoms, lowers postoperative delirium risk, shortens hospital stay, and improves postoperative quality of life. The stability of anesthesia depth is closely associated with postoperative mental health outcomes, providing new clinical evidence and individualized strategies for perioperative management of high-risk elderly patients.

Keywords: Elderly patients; Gastric cancer; Sleep disorder; Electroencephalogram monitoring; Anesthesia depth; Postoperative anxiety; Postoperative depression

Core Tip: This study demonstrates that electroencephalogram (EEG)-guided anesthesia significantly reduces postoperative anxiety and depression in elderly gastric cancer patients with sleep disorders, with greatest benefits in severe cases. Anesthesia depth stability, rather than absolute values, critically influences mental health outcomes. EEG monitoring also reduces drug costs by 18.6% and complications, supporting routine Bispectral Index implementation in this vulnerable population.