The median effective volume of ultrasound-guided thoracic paravertebral nerve block with 0.3% ropivacaine in radical thoracoscopic surgery for lung cancer

Article type: Research Article

Authors: Zhang, Wen-Qing | Li, Jia-Bin | Huang, Ye | Huang, Na-Qing | Huang, Fei-Bin | Huang, Qiao-Wen | Jiang, Li-Wei | Lu, Zhi-Wei^*

Affiliations: Department of Anesthesiology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou, Fujian, China

Correspondence: [*] Corresponding author: Zhi-Wei Lu, Department of Anesthesiology, Zhangzhou Affiliated Hospital of Fujian Medical University, Shenglixi Road No. 59, Zhangzhou, Fujian 363000, China. E-mail: zwmn_lu06@163.com.

Abstract: BACKGROUND: Ultrasound-guided needle placement has revolutionized the thoracic paravertebral block technique and can be applied in thoracoscopic surgery. OBJECTIVE: This study investigated the median effective volume (EV50) of an ultrasound-guided single shot of 0.3% ropivacaine used as a thoracic paravertebral nerve block for the radical thoracoscopic resection of lung cancer. METHODS: A total of 27 patients who received a single shot of ultrasound-guided thoracic paravertebral nerve block and underwent radical thoracoscopic resection of lung cancer were enrolled in this study between February 10 and August 13, 2018. All patients were rated as ASA grades I or II. Using ultrasound as a guide, the block needle was gradually pushed through the lateral costotransverse ligaments to the thoracic paravertebral space by the in-plane technique. After confirming the absence of blood or cerebrospinal fluid, 1–2 ml of 0.3% ropivacaine hydrochloride was injected to confirm that the position of the needle was appropriate, and a pre-determined volume of 0.3% ropivacaine hydrochloride was then administered to the patients. Sensory testing by pinprick was performed every 5 minutes for 30 minutes following the thoracic paravertebral block injection to identify the time segments during which the loss of sensation to the pinprick and its blocking effect occurred. RESULTS: All patients completed the study and 14 (51.8%) had a successful block. CONCLUSION: The EV50 of 0.3% ropivacaine was 18.46 ml (95% CI 17.09–19.95 ml) and the EV95 was 20.89 ml.

Keywords: Median effective volume, sequential trial, thoracic paravertebral nerve block, ultrasound-guided, thoracoscopic radical surgery

DOI: 10.3233/THC-213608

Journal: Technology and Health Care, vol. 30, no. 6, pp. 1343-1350, 2022