NCT07446959

Minimum Effective Volume of Bupivacaine for Serratus Posterior Superior Intercostal Plane Block in Video-Assisted Thoracoscopic Surgery

Determination of the Median Effective Volume (ED50) of Bupivacaine for Serratus Posterior Superior Intercostal Plane Block in Patients Undergoing Video-Assisted Thoracoscopic Surgery Using the Dixon Up-and-Down Method

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 27 (estimated)
• Sponsor: Bursa City Hospital · Other Government
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study aims to determine the minimum effective volume of bupivacaine required for the serratus posterior superior intercostal plane (SPSIP) block in patients undergoing video-assisted thoracoscopic surgery (VATS). The SPSIP block is an ultrasound-guided regional anesthesia technique used to provide postoperative pain relief after thoracic surgery. Using a stepwise dose-adjustment method, the volume of local anesthetic will be increased or decreased based on the effectiveness of the block in each patient. The main outcome of the study is to identify the volume that provides effective pain control in 50% of patients. The results may help optimize pain management while minimizing drug exposure.

Detailed description

This prospective interventional dose-finding study is designed to determine the median effective volume (ED50) of 0.25% bupivacaine for ultrasound-guided serratus posterior superior intercostal plane (SPSIP) block in patients undergoing video-assisted thoracoscopic surgery (VATS). The up-and-down sequential allocation method described by Dixon and Massey will be used. The initial volume of bupivacaine will be administered to the first patient, and subsequent volumes will be adjusted in 2 mL increments according to the response of the preceding patient. If the block is successful, the volume for the next patient will be decreased by 2 mL. In case of block failure, the volume will be increased by 2 mL. Block success will be defined as the presence of sensory loss to cold in at least two consecutive dermatomes between T3 and T6, assessed 20-30 minutes after block performance, combined with a cumulative fentanyl requirement of less than 2 µg/kg within the first 60 minutes after induction of general anesthesia. Failure will be defined as absence of adequate sensory blockade or the need for fentanyl ≥2 µg/kg. The up-and-down sequence will be continued until nine reversal points are obtained. The ED50 will be calculated as the mean of the midpoint doses of all independent success-failure pairs. Secondary outcomes will include postoperative pain scores and opioid consumption. This study aims to provide clinically relevant data to optimize the volume of local anesthetic for SPSIP block while maintaining effective analgesia and minimizing potential adverse effects.

Conditions

• Postoperative Pain Management
• Video-assisted Thoracoscopic Surgery (VATS)

Interventions

Type	Name	Description
OTHER	Ultrasound-Guided Serratus Posterior Superior Intercostal Plane Block	Ultrasound-guided serratus posterior superior intercostal plane block performed prior to general anesthesia in patients undergoing video-assisted thoracoscopic surgery (VATS). A 0.5% bupivacaine solution is injected, and the volume is adjusted in 2 mL increments according to the Dixon up-and-down sequential allocation method to determine the median effective volume (ED50).

Timeline

• Start date: 2026-03-15
• Primary completion: 2026-07-15
• Completion: 2026-07-15
• First posted: 2026-03-03
• Last updated: 2026-03-31

Locations

1 site across 1 country: Turkey (Türkiye)