To investigate the effects of sevoflurane and propofol on lipid metabolism and to analyze the relationship between lipid metabolism-related indicators and cognitive function.

A total of 80 elderly patients scheduled for laparoscopic radical resection of colorectal cancer in Qidong Hospital of Traditional Chinese Medicine from January 2023 to March 2025 were enrolled. According to a random number table, patients were allocated to the sevoflurane group (S group) or the propofol group (P group), with 40 patients in each group. Anesthesia induction: Patients in the S group received inhalation of 8% sevoflurane (oxygen flow 6-8 L/min, oxygen concentration 40%), intravenous rocuronium 0.3 mg/kg, and sufentanil 0.3 μg/kg. Patients in the P group received intravenous propofol 1.5-2.0 mg/kg, rocuronium 0.6-1.0 mg/kg, and sufentanil 0.6-1.0 μg/kg. Anesthesia maintenance: Patients in the S group received inhaled sevoflurane at 0.8-1.3 MAC, continuous intravenous infusion of remifentanil 0.05-2.0 μg/(kg·min), and intermittent intravenous rocuronium 0.3 mg/kg. Patients in the P group received continuous intravenous infusion of propofol 4.0-12.0 mg/(kg·h) and remifentanil 0.05-2.0 μg/(kg·min), with intermittent intravenous rocuronium 0.6 mg/kg. MMSE scores were assessed at 1 day before anesthesia (T0), and on postoperative day 1 (T1), day 3 (T3), and day 7 (T7). Venous blood samples were collected at the same time points to measure lipid metabolism-related indicators, including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), apolipoprotein A1, and lipoprotein (a). In addition, intra-induction hypotension, bradycardia, induction time, postoperative nausea and vomiting (PONV), and recovery time were recorded.

At T1 and T3, MMSE scores, apolipoprotein A1 in the S group were significantly lower than those in the P group (P<0.05), while lipoprotein (a) levels were significantly higher (P<0.05). Spearman correlation analysis showed that apolipoprotein A1 was positively correlated with MMSE scores at T1 and T3 (ρ=0.797, P<0.001; ρ=0.590, P<0.001), whereas lipoprotein (a) was negatively correlated with MMSE scores at T1 and T3 (ρ=-0.734, P<0.001; ρ=-0.388, P=0.001). During anesthesia induction, the incidence of hypotension was significantly lower in the S group compared with the P group (P<0.05), while the induction time was significantly longer (P<0.05).

Sevoflurane can reduce the incidence of hypotension during anesthesia induction, but may increase the risk of early postoperative cognitive decline in elderly patients undergoing colorectal cancer surgery. Propofol shows advantages in cognitive protection and lipid metabolism stability. Lipid metabolism-related indicators, especially apolipoprotein A1 and lipoprotein (a), are closely associated with cognitive function, suggesting that lipid metabolism may play a key role in mediating the impact of anesthetic techniques on postoperative cognition.