Comparison of ultrasound-guided continuous intertransverse process block and continuous erector spinae plane block for postoperative analgesia after uniportal video-assisted thoracoscopic surgery: protocol for a double-blind, prospective, randomised controlled trial.

introductionVideo-assisted thoracoscopic surgery (VATS) has become the predominant method for lung cancer diagnosis and resection, with over 80% adoption in relevant surgeries. With technological advancements, uniportal VATS is now widely employed. However, it still poses a significant risk of moderate to severe acute postoperative pain, potentially leading to chronic post-thoracotomy pain syndrome (PTPS). Therefore, effective postoperative analgesia is crucial. Regional block techniques have gradually gained wide attention. Specifically, paravertebral block (PVB) has been considered the 'gold standard' for thoracic analgesia, but its application involves risks due to the challenging anatomy. The erector spinae plane block (ESPB) and intertransverse process block (ITPB) have emerged as alternatives. ESPB showed non-inferiority to PVB in pain management and recovery quality. However, the mechanism of ESPB and its consistency in providing analgesia are not fully understood. ITPB, targeting the 'posterior space of the superior costotransverse ligament', offers theoretical advantages in drug diffusion due to its closer proximity to the paravertebral space than ESPB. Despite these advancements, there is a lack of randomised controlled trials (RCTs) assessing the comparative efficacy of continuous ESPB and ITPB. This study aims to address these gaps by comparing the analgesic effects and recovery quality of continuous ESPB and ITPB in patients undergoing single-port VATS. METHODS AND ANALYSIS: A double-blind RCT will be conducted, enrolling 96 patients electively undergoing single-port thoracoscopic surgery, randomly assigned to either the experimental group (ITPB group) or the control group (ESPB group). After routine surgery, block intervention and continuous pump catheterisation will be performed. The primary assessment will be the numeric rating scale (NRS) scores at 24 hours. Secondary outcomes include NRS at other time points, block effectiveness, Quality of Recovery-15 scores and chronic pain-related scores. Evaluations will be conducted at 0, 2, 6, 12, 24 and 48 hours. Additional assessment indicators include time to first self-administration of pulse analgesia pump, number of self-administrations within 48 hours, use of non-steroidal anti-inflammatory drugs and opioids postoperatively, Comprehensive Complication Index (CCI) score, length of hospital stay, incidence of adverse events and complications, patient satisfaction score and assessment of PTPS incidence at 3 months postoperatively using the Brief Pain Inventory short form and the Short-Form McGill Pain Questionnaire. ETHICS AND DISSEMINATION: The study was reviewed and approved by the Medical Ethics Committee of the Fifth Affiliated Hospital of Sun Yat-sen University (No. K44-1, 2024). The results of the study will be submitted for publication in a peer-reviewed journal with online accessibility. TRIAL REGISTRATION NUMBER: ChiCTR2400082856.