Objective To evaluate the effect of Dexmedetomidine (Dex) combined with remote ischemic preconditioning (RIPC) on regional cerebral oxygen saturation (rSO₂) and postoperative delirium (POD) in elderly patients with one-lung ventilation (OLV).Methods 80 elderly patients with elective thoracoscopic OLV were selected, and they were divided into 4 groups (20 cases in each group) according to the random number table: the control group (C group), the pure Dex group (Dex group), simple RIPC group (RIPC group) and Dex combined with RIPC group (Dex + RIPC group). Record the rSO₂ of each group before induction of anesthesia (T₀), before OLV (T₁), 10 min after OLV (T₂), 30 min after OLV (T₃), end of OLV (T₄) and at the end of surgery (T₅), serum interleukin-10 (IL-10), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) level at T₀, T₂, T₄, 6 h after surgery (T₆) and 24 h after surgery (T₇), and the occurrence of adverse postoperative complications in each group. POD was evaluated 1 day after operation.Results At T₂, rSO₂ in the Dex + RIPC group was significantly higher than that in the other 3 groups (P < 0.05); At T₃ and T₄, rSO₂ in C, Dex, RIPC and Dex + RIPC group increased in sequence, and the differences were statistically significant (all P < 0.05); At T₅, rSO₂ in the RIPC group was significantly higher than that in group C and Dex group (P < 0.05), the Dex + RIPC group was significantly higher than the RIPC group (P < 0.05), but there was no statistical difference between the C and Dex groups. Compared with C group, the difference in CAM-CR scores of Dex group and RIPC group was significantly reduced at 1 day after surgery (P < 0.05), and the Dex + RIPC group was significantly lower than that of Dex group and RIPC group (P < 0.05). The incidence of POD in Dex + RIPC group was significantly lower than that in group C (P < 0.05). Compared with C group, IL-6 and TNF-α in Dex group, RIPC group and Dex + RIPC group decreased at T₄, T₆ and T₇, while IL-10 increased. The incidence of postoperative nausea and vomiting and agitation in Dex + RIPC group was significantly reduced (P < 0.05).Conclusion Dex combined with RIPC can stabilize the rSO₂ level after OLV in elderly patients, and can effectively inhibit the release of inflammatory cytokines and reduce the incidence of postoperative delirium.