Effect of ketamine on cellular immunity and inflammation in patients who undergo laparoscopic colon cancer surgery: a retrospective study.

Objective: Anesthesia during the surgery impairs immune systems. Ketamine is an anesthetic with immune protective effects. This study intended to investigate the effect of a ketamine-involved anesthetic regimen on cellular immunity and inflammatory cytokines in patients who undergo laparoscopic colon cancer surgery.

Methods: This retrospective study screened 60 patients who underwent laparoscopic colon cancer surgery with an anesthesia regimen involving ketamine (N = 30, ketamine group) or not (N = 30, opioid group). Data on surgery-related parameters, blood pressure, heart rate (HR), blood routine examination parameters, cluster of differentiation (CD) 3 and CD4 T cells, inflammatory cytokines, and adverse reactions were retrieved. Time points were defined as entering the operating room (T1), 5 min after anesthetic induction (T2), the end of surgery (T3), and 24 h after surgery (T4).

Results: The 1 h-postoperative pain score ( < 0.001) and length of stay ( < 0.001) were lower in ketamine group than in opioid group. Blood pressure and HR from T1 to T4 were more stable in ketamine group than in opioid group. Neutrophils ( < 0.001), CD3 ( < 0.001) and CD4 T cells ( = 0.002) at T4 were higher in ketamine group than in opioid group. Interleukin (IL)-10 at T3 ( < 0.001) and T4 ( < 0.001) were higher, while IL-6 at T3 ( < 0.001) and T4 ( < 0.001) were lower in ketamine group than in opioid group. There was no discrepancy in incidences of adverse reactions between groups.

Conclusion: A ketamine-involved anesthetic regimen seems to be correlated with the improvement of cellular immunity and inflammation with a tolerable safety profile. However, more studies with a prospective, randomized, controlled design are needed to verify this finding and draw a solid conclusion.