Objective:To explore the effects of phased goal directed fluid therapy (GDFT) during anesthesia surgery on tissue perfusion and cognitive function in patients undergoing radical lung cancer surgery.Methods:A total of 108 lung cancer patients were prospectively selected and randomly divided into a control group and a study group using a random number table method. The control group received classical restrictive liquid therapy, while the study group received staged GDFT. We compared the surgical time, intraoperative blood loss, colloid fluid dosage, crystalloid fluid dosage, total output, and urine volume between two groups of patients; Two groups of patients were compared in terms of oxygenation index (OI), respiratory index (RI), central venous oxygen saturation (ScvO 2), lactate (Lac), central venous arterial carbon dioxide partial pressure difference (Pcv-aCO 2), oxygen supply index (DO 2I), and oxygen uptake rate (O 2ERe) before anesthesia induction (T 0), before single lung ventilation (T 1), 1 hour of single lung ventilation (T 2), immediate resumption of dual lung ventilation (T 3), 30 minutes of dual lung ventilation (T 4), and after surgery (T 5); The Mini Mental State Examination (MMSE) was used to evaluate the cognitive function scores of two groups of patients 1 day before surgery and 1 and 3 days after surgery, while recording the incidence of cognitive dysfunction (POCD) and pulmonary complications (including pulmonary infection, acute lung injury, pulmonary embolism, pulmonary edema, atelectasis, etc.) within 3 days after surgery. Results:The amount of crystal fluid and urine output in the research group was significantly lower than that in the control group, while the amount of colloidal fluid was significantly higher than that in the control group (all P<0.05). The OI of the study group T 1-T 5 was significantly higher than that of the control group, while the RI of T 2-T 5 was significantly lower than that of the control group (all P<0.05). The ScvO 2 of the study group T 1 to T 5 was significantly higher than that of the control group, and the Lac was significantly lower than that of the control group (all P<0.05); The MMSE scores of both groups of patients were significantly lower than those before surgery on day 1 and 3 after surgery, and the MMSE scores of the study group were significantly higher than those of the control group on day 1 and 3 after surgery (all P<0.05). The incidence of POCD within 3 days after surgery in the study group was 16.67%(9/54), lower than 37.04%(20/54) in the control group (χ 2=5.704, P=0.017); The incidence of pulmonary complications in the study group was lower than that in the control group (5.56% vs 22.22%, χ 2=4.955, P=0.026). Conclusions:The application of staged GDFT during anesthesia in patients undergoing radical lung cancer surgery can further improve tissue perfusion, improve microcirculation and oxygen supply-demand balance of systemic organs and tissues, including the brain, alleviate perioperative brain function damage, and reduce the occurrence of postoperative POCD compared to conventional liquid therapy.