The Effect of Esketamine on Postoperative Fatigue Syndrome in Middle-Aged and Elderly Patients Undergoing Lumbar Vertebral Body Fusion Surgery—A Retrospective Study

Aims/Background: Lumbar spine disease frequently occurs in middle-aged and elderly individuals, significantly affecting their physical and mental health. Posterior lumbar interbody fusion (PLIF) is widely used for treating these diseases; however, postoperative complications may lead to fatigue. Therefore, we explore the effect of different postoperative doses of esketamine on postoperative fatigue syndrome (POFS) in patients undergoing PLIF. Methods: This retrospective study analyzed the clinical data of 105 patients undergoing PLIF between June 2022 and September 2024. Patients were divided into high-dose esketamine group (Group HS, 30 cases), low-dose esketamine group (Group LS, 35 cases) and control group (Group C, 40 cases) based on the preoperative dosages of esketamine. Furthermore, intraoperative sufentanil usage, heart rate (HR) and mean arterial pressure (MAP) were assessed at different times during surgery. Recovery conditions and the length of hospitalization were compared across the three groups. Fatigue levels and psychological status, evaluated using the Christensen fatigue scale, self-rating depression scale (SDS), and self-rating anxiety scale (SAS), were assessed preoperatively and on postoperative days 3 and 5. Pain intensity was assessed using the numeric rating scale (NRS) at 30 min after awakening and on postoperative days 1 and 2. The incidence of POFS and adverse drug reactions (ADRs) was also analyzed among the three groups. Results: Compared to T0, MAP and HR scores decreased significantly across all groups from T1 to T3 (p < 0.05). From T1–T3, MAP and HR levels were significantly reduced in Group HS than the other groups, while Group LS demonstrated lower levels than Group C (p < 0.05). Intraoperative sufentanil usage was also substantially lower in Group HS than the other groups, with Group LS using less than Group C (p < 0.05). Upon leaving the recovery room, Group HS had a significantly higher recovery score than the other groups (p < 0.05), with Group LS scoring higher than Group C (p < 0.05). On postoperative day 3 and 5, Group HS exhibited lower SDS and SAS scores than the other groups (p < 0.05), while Group LS exhibited lower scores than Group C (p < 0.05). Furthermore, fatigue scores were considerably lower in Group HS compared to the other groups (p < 0.05), whereas the difference between Group C and Group LS did not achieve statistical significance (p > 0.05). The incidence of POFS in Group HS was 46.67%, significantly lower than in Group LS (88.57%) and Group C (92.50%, p < 0.05). On postoperative days 1 and 2, Group HS had lower NRS scores, followed by Group LS, with Group C exhibiting the highest scores (p < 0.05). Additionally, there were no significant differences among the three groups in awakening time, extubation time, length of hospitalization, and incidence of ADR (p > 0.05). Conclusion: Preoperative intravenous esketamine administration effectively prevents POFS in middle-aged and elderly patients undergoing PLIF under general anesthesia in the prone position. An esketamine dose of 0.5 mg/kg shows superior efficacy in reducing postoperative anxiety, depression, and pain levels.