Permissive hypercapnia combined with goal-directed fluid therapy improve postoperative mental health in elderly patients undergoing laparoscopic surgery

Figure 1 Independent predictors of postoperative depression. The analysis shows that the permissive hypercapnia + goal-directed fluid therapy protocol significantly reduced the risk of depression during the 7-day follow-up (hazard ratio = 0.45). Other factors linked to higher depression risk included high tumor necrosis factor α levels (> 40 pg/mL), high cortisol levels (> 350 nmol/L), and longer hospital stays (> 6 days). PH: Permissive hypercapnia; GDFT: Goal-directed fluid therapy; TNF-α: Tumor necrosis factor α; HR: Hazard ratio.