Abstract: Objective  To investigate the regulating effects of single erector spinae plane block(ESPB)+patient controlled intravenous analgesia(PCIA) on the degree of pain and comfort, psychological status, stress hormones, pulmonary surfactant protein A(SP-A), and tumor necrosis factor-α(TNF-α) after thoracoscopic wedge resection of the lung. 
Methods  In total, 82 patients undergoing thoracoscopic wedge resection of the lung were divided into control group(n=41) and observation group(n=41), according to random number table method. The control group underwent PCIA and the observation group underwent ESPB and PCIA. The duration of operation, intraoperative sufentanil dosage, intraoperative bleeding, times of PCIA compression within 24 h after operation, length of hospital stay, mean arterial pressure(MAP), heart rate(HR), visual analog scale(VAS), Kolaba′s General Comfort Questionnaire(GCQ), and state-trait anxiety inventory(STAI), stress hormones［cortisol(Cor), adrenocorticotropic hormone(ACTH), prostaglandin E2(PGE2)］, SP-A, TNF-α and security were compared between two groups. 
Results  The dosage of sufentanil during operation and the number of PCIA compression within 24 h after operation in the observation group were lower or less than those in the control group(P＜0.05). MAP and HR at insertion of the double-lumen tube, at skin incision, and at extubation in  two groups were higher than those before anesthesia induction, and lower in the observation group than in the control group(P＜0.05). The VAS score for pain, S-AI score and T-AI score of the observation group were lower than those of the control group at 2, 3 and 4 d after operation, and the GCQ score was higher than that of the control group(P＜0.05). Cor, ACTH, ACTH, PGE2, SP-A and TNF- α in the observation group were lower than those in the control group at 1, 2, 3 and 4 d after operation(P＜0.05). There was no significant difference in the incidence of adverse reactions between two groups(P＞0.05). 
Conclusion  Single ESPB + PCIA in patients undergoing thoracoscopic wedge resection of the lung has a significant analgesic effect, which can reduce the use of anesthetics, ensure the safety of the medication, and reduce the postoperative stress response of the whole body. In addition, it is of great significance in improving the psychological state and comfort of patients, with good safety. 

Key words: Thoracoscopy, Single erector spinae plane block, patient-controlled intravenous analgesia