4. Discussion
paravertebral vascular injury, postoperative pain, paravertebral muscle pain, paravertebral pain, nerve block, pain, vascular injury, postoperative paraspinal muscle pain, paraspinal muscle, intercostal vascular injury, muscle pain, hypotension, paraspinal muscle pain, block-related, tissue damage, thoracic nerve block
LOCAL ANESTHETICS, COMPLICATIONS, DEEP VEIN THROMBOSIS
The gold standard of traditional thoracic analgesia is the epidural block (TEB). Compared with the epidural block, the PVB has been found to have the same analgesic effect and fewer complications, and so it is regarded as the best alternative to the epidural block. It has also become the object of comparison of the effectiveness of the most new thoracic nerve block techniques. Most of the previous studies [Although there was no significant difference in the dynamic pain score within 48 hours between the PVB and RIB groups, the static pain score in the PVB group was higher than that in the rib group, which was mainly attributed to the paravertebral muscle pain at the injection site in some patients (7/40) in the PVB group. One of the patients still complained of muscle pain at the position of the paravertebral block at the follow-up one month after the operation. This is because the position of the paravertebral space is deeper than the space between the rhomboid muscle and the intercostal space, and the nerve block needle needs to cross more layers of the tissue to reach the block position, resulting in more severe tissue damage, especially in repeated cases, the paravertebral muscle pain would worsen. Similar clinical results have also been reported in the previous studies [Clinical studies [In addition, the probability of intraoperative hypotension in the PVB group was also higher than that in the RIB group. We also believe this is related to the diffusion mode of local anesthetic drugs in the PVB. Although the PVB transfers the block site from the intraspinal to the paravertebral triangle compared with TEB, local anesthetic drugs could diffuse into the spinal canal from the paravertebral triangle. Local anesthetics into the spinal canal may block the sympathetic nerve and cause blood pressure to drop [In this experiment, there were 3 cases in which paravertebral vascular injury occurred in the paravertebral block under ultrasound, and the local anesthetic could not continue to be administered. Song et al. reported a similar case of PVB with severe intercostal vascular injury [Postoperative analgesia is a good starting point to accelerate postoperative rehabilitation. From the results of this study, it is concluded that the postoperative pain score in the RIB group and the PVB group is lower than that in the GA group. Furthermore, the incidence of postoperative paraspinal muscle pain in the RIB group is lower than that in the PVB group; the postoperative pain score is lower. Compared with simple intravenous drug analgesia, the nerve block reduces the dosage of opioid drugs on the basis of ensuring better analgesia that helps patients to go to the ground as soon as possible, promotes the recovery of gastrointestinal function, and avoids the occurrence of deep vein thrombosis and quickly return to the state of life before the operation. Correspondingly, the QoR15 score covers all essential factors of rapid rehabilitation and has been widely used in postoperative recovery evaluation. In this study, the QoR15 score of the PVB group and the RIB group was higher than that of the GA group within 48 hours after the operation, while that of the RIB group was higher than that of the PVB group. This shows that both PVB and RIB can promote the postoperative rehabilitation of patients primarily since the RIB provides adequate analgesia and has fewer block-related complications. The QoR15 score post operation is higher than that of the other two groups.The different anatomical basis of the PVB and RIB lead to other block characteristics from the two blocks. Compared with the TEB, the PVB is the transfer of blocks from the intraspinal to the extravertebral triangle through the skin, subcutaneous tissue, paraspinal muscle, and costal transverse process ligament and finally reach the paraspinal triangle to inject a local anesthetic into it. The RIB injects local anesthetic into the space between the rhomboid muscle and the intercostal muscle in the area between the spine and the scapula. The block site is shallower than PVB, and the tissue damage is slighter than PVB; the incidence of paraspinal muscle pain is extremely low. Because the paravertebral triangle is adjacent to the intervertebral foramen, there are also intercostal arteries and their branches with significant variation, intercostal vascular injury, and local anesthetic drugs enter the spinal canal and cause hypotension are common complications of PVB. The block site of the RIB is far away from the paravertebral triangle to avoid the abovementioned complications. As a kind of fascial block, the RIB can obtain the range of multiple intercostal blocks with a local anesthetic drug spreading multiple intercostal segments easily between the two layers of muscle in a single intercostal block. In comparison, the range of blocks caused by a single intercostal block of PVB has intense uncertainty.In conclusion, compared with the simple general anesthesia group, both PVB and RIB can reduce perioperative opioid consumption, provide adequate analgesia for patients, and accelerate their recovery of patients. Through this double-blinded, randomized, controlled study, we have first compared the efficacy between standard thoracic analgesia (such as PVB) and ultrasound-guided RIB and found that RIB has a better analgesic effect, especially to avoid paravertebral pain caused by block, and the operation of RIB is more straightforward and the safety is higher. Through this study, we can provide guidelines for analgesic management of acute pain after video-assisted thoracic surgery.