Abstract: Objective To investigate the effects of paravertebral nerve block(PVNB) under thoracoscopic direct vision on postoperative pain,stress response and T lymphocyte subsets in patients undergoing thoracoscopic lobectomy under general anesthesia.Methods A total of 104 patients who were scheduled to undergo thoracoscopic lobectomy in the hospital from January 2021 to August 2023 were enrolled in this study.They were divided into the control group(52 cases) and the observation group(52 cases) using the random number table.The control group was given general anesthesia,and the observation group was given PVNB on the basis of general anesthesia.Both groups received patient-controlled intravenous analgesia(PCIA) after surgery.Visual analogue pain (VAS) scores were recorded 1 hour (T₁), 6 hours (T₂), 12 hours (T₃), 24 hours (T₄) and 48 hours (T₅) after surgery in both groups.The drug use for PCIA,postoperative stress response,changes in T lymphocyte subsets,and incidence rates of adverse reactions in the two groups were analyzed.Results From T₁ to T₅,VAS scores of the two groups increased firstly and then decreased.From T₁ to T₄,VAS scores of the observation group were lower than those of the control group(P<0.05).The first pressing time of PCIA in the observation group [(11.18±3.29) h] was longer than that in the control group [(9.61±2.48) h].The pressing times of PCIA and dosage of sufentanil [(4.63±1.51) times and(46.29±6.24) ml] were lower than those in the control group [(7.22±1.86) times and(55.41±7.88) ml](P<0.05).At 24 h after surgery,the levels of cortisol,norepinephrine and blood glucose in the observation group [(252.27±19.75) ng/ml,(346.63±25.06) ng/ml and(5.48±0.72) mmol/L] were lower than those in the control group [(275.78±21.46) ng/ml,(381.71±23.71) ng/ml and(6.03±0.64) mmol/L](P<0.05).The levels of CD3⁺,CD4⁺,CD8⁺ T lymphocyte count and CD4⁺/CD8⁺ T lymphocyte count in the observation group [(0.57±0.05)×10⁹/L,(0.39±0.04)×10⁹/L,(0.26±0.02)×10⁹/L and (1.50±0.35)] were higher than those in the control group[（0.55±0.05）×10⁹/L,（0.36±0.03）×10⁹/L,（0.29±0.04）×10⁹/L and （1.24±0.31）](P<0.05).The incidence rates of adverse reactions in the two groups were 1.92% and 2.77%,without statistically significant difference between groups(P＞0.05).Conclusion Applying PVTB under thoracoscopic direct vision to patients undergoing thoracoscopic lobectomy under general anesthesia is beneficial for reducing postoperative pain,stress response,and the influence on immune system.

Key words: thoracoscopy;paravertebral nerve block;general anesthesia;lobectomy;stress response;T lymphocyte subset