Study limitations
weakness, cutaneous block, ESPB
DECUBITUS, SIDE EFFECT
First, the differences in NRS between groups for the overall postoperative period were statistically significant, but we could not find them at a specific time. This result could be associated with statistical power. Thus, there is a need for further research in which sample size is added to increase statistical power. Second, 2 different analgesic procedures were performed with different positions (ESPB prone position vs. TEA lateral decubitus position). Thus this study had a weakness in the double-blinded method. However, the patients did not know which group they belonged to because it was based on their lack of prior knowledge in ESPB or TEA. Third, it was difficult to check the dermatomal sensory range, especially in the ESP block. We assessed dermatome sensitivity less than 1 h after surgery when the patient might not be fully conscious. Furthermore, the extent of the cutaneous block has some interindividual variability based on local anesthetic spread into the interfascial plane.Our results imply that ESP blocks could be an alternative to conventional techniques in patients with VATS due to their simplicity and safety, especially as a part of a multimodal analgesic strategy. Therefore, ESP blocks should be considered for routine use in patients undergoing thoracic surgery if TEA or TPVB are not considered or are contraindicated. However, further studies are necessary to confirm the efficacy of ESP blocks compared to other techniques and to establish the optimal dose and regimen.In conclusion, continuous ESP block might be inferior to TEA; however, this technique may have tolerable analgesic efficacy and a better side effect profile than continuous epidural analgesia. Therefore, it could be an alternative to conventional regional analgesic techniques as a component of multimodal analgesia.