Abstract:

Objective To analyze the effects of epidural block combined with general anesthesia on cognitive function and cellular immune function in elderly patients after radical lung cancer operation. Methods Patients treated at our hospital were randomly assigned to be treated with intravenous anesthesia （n=20） or the combination of epidural block and general anesthesia （n=20）. Levels of T cell subsets and NK cells were determined using double antibody-sandwich enzyme-linked immunosorbent assay （ELISA）. The simple mental state examination （MMES） was used to assess cognitive function in both groups. Pain and sedation were assessed using the VAS score and Ramsay sedation score. Postoperative time to spontaneous breathing，eye opening and extubation were also recorded. Results The combination therapy group showed significantly shorter operating time than the intravenous anesthesia group，as well as significantly shorter time to spontaneous breathing，eye opening，and extubation（P<0.05）. The two treatment groups showed similar VAS pain scores and Ramsay sedation scores at 6 and 12 h postoperatively （P>0.05）. Compared to preoperative day 1，levels of CD3⁺，CD4⁺，and NK cells as well as the CD4⁺/CD8⁺ ratio were lower on postoperative day 1 （P<0.05），while the level of CD8⁺cells was higher on postoperative day 1（P<0.05）. Levels of CD3⁺，CD4⁺，and NK cells as well as the CD4⁺/CD8⁺ ratio on postoperative day 1 and postoperative day 7 were significantly higher in the combination therapy group than in the intravenous anesthesia group （P<0.05），while the level of CD8⁺ cells was no significant difference. In two treatment groups，levels of CD3⁺，CD4⁺，and NK cells cells as well as the CD4⁺/CD8⁺ ratio were significantly higher on postoperative day 7 than on postoperative day 1，while the level of CD8⁺ cells was significantly lower. On postoperative day 7，levels of CD3⁺，CD4⁺，and NK cells as well as the CD4⁺/CD8⁺ ratio were significantly higher in the combination therapy group than in the intravenous anesthesia group，while the level of CD8⁺ cells was significantly lower（P<0.05）. Both treatment groups scored significantly lower on cognitive function on postoperative than on preoperative（P<0.05），while the combination therapy group scored significantly higher than the intravenous anesthesia group（P<0.05）. Conclusion Epidural block combined with general anesthesia is associated with significantly better cognitive function and recovery of cellular immune function in elderly patients following radical lung cancer surgery.

Key words: Lung neoplasm, Epidural block, General anesthesia, Lung cancer operation, Elderly people, Cognitive function, Cellular immune function