Intraoperative intravenous lidocaine exerts a protective effect on cell-mediated immunity in patients undergoing radical hysterectomy.

ABSTRACT

Surgical procedures cause a decrease in lymphocyte proliferation rate, an increase in apoptosis and shifts the balance of T­helper (Th)1/Th2 cells towards anti­cell­mediated immunity (CMI) Th2 dominance, which is relevant to the immunosuppressive effects of CMI, postoperative septic complications and the formation of tumor metastasis. Previous studies have revealed that lidocaine exhibits antibacterial actions; regulating inflammatory responses, reducing postoperative pain and affecting the duration spent in hospital. Thus, the present study hypothesized that lidocaine may exert a protective effect on the CMI of patients undergoing surgery for the removal of a primary tumor. A total of 30 adult female patients diagnosed with cervical cancer were recruited to the present study and were randomized into two groups. The lidocaine group received an intravenous bolus dose of 1.5 mg/kg lidocaine, followed by continuous infusion at 1.5 mg/kg/h until discharge from the operating room. The control group received the same volume of normal saline. A 10 ml sample of venous blood was drawn, and the lymphocytes were isolated using Ficoll­paque 1 day prior to surgery, at discharge from the operating room and 48 h post­surgery. The proliferation rate of the lymphocytes was assessed using a Cell Counting Kit­8 assay and was found to be higher in the lidocaine group. The early apoptosis of lymphocytes was attenuated following lidocaine treatment at 48 h post­surgery, as detected using flow cytometry with Annexin V­fluorescein isothiocyanate/propidium iodide staining. The level of interferon (IFN)­Î³ in the serum at 48 h was significantly decreased following surgery in the control group, compared with the pre­surgical values (3.782 ± 0.282, vs. 4.089 ± 0.339 pg/ml, respectively) and the ratio of IFN­Î³ to interleukin­4 was well preserved in the lidocaine group. In conclusion, the present study demonstrated that the intraoperative systemic administration of lidocaine exerted a protective effect on CMI in patients with cervical cancer undergoing radical hysterectomy. This may be beneficial in reducing the occurrence of postoperative septic complications and tumor metastasis formation.