The Impact of Ultrasound-Guided Superficial and Deep Paravertebral Nerve Blocks at the Superior Costotransverse Ligament on Hemodynamics During the Induction Phase of Thoracoscopic Lung Lobectomy: A Multicenter, Double-Blind, Randomized Controlled Trial

This study aims to determine whether performing a paravertebral nerve block at the superficial surface of the superior costotransverse ligament (SCTL) (without needle penetration of the SCTL) is more effective in maintaining hemodynamic stability during the induction phase of thoracoscopic lung lobectomy compared to the deep surface of the SCTL (with needle penetration of the SCTL). This is a multicenter, double-blind, randomized controlled trial enrolling a total of 168 participants across five hospitals. To investigate the effects of different nerve block methods on hemodynamics during induction, participants will be allocated to either the deep plane SCTL block group (T group) or the superficial plane SCTL block group (S group) using a stratified randomization scheme. The stratification accounts for a 40% proportion of hypertensive patients within each treatment group at each center. Thirty minutes before surgery, patients will receive either an ultrasound-guided deep SCTL block (needle penetrating the SCTL) or a superficial SCTL block (needle not penetrating the SCTL) in the pre-anesthesia room. The target vertebral levels for the block are T4 and T6, and 20 mL of 0.375% ropivacaine hydrochloride solution will be injected slowly at each site. Researchers will document whether subpleural compression is observed on ultrasound imaging and monitor for complications such as hemothorax, pneumothorax, local hematoma, local anesthetic toxicity, epidural anesthesia, or total spinal anesthesia during the procedure. Another investigator, blinded to the group allocation, will evaluate patients after the nerve block procedure, recording any occurrences of hemothorax, pneumothorax, local hematoma, local anesthetic toxicity, epidural block, or total spinal anesthesia. Cold sensitivity tests using the temperature method will be conducted at the midaxillary line within the corresponding blocked regions at 5, 10, 20, and 30 minutes post-block, and the sensory blockade level wi