Two-Point Versus Single-Point Serratus Anterior Plane Block for Post-Thoracoscopic Surgery Analgesia

Comparison of Ultrasound-Guided Two-Point Combined vs Single-Point Serratus Anterior Plane Block for Postoperative Analgesia in Thoracoscopic Surgery: A Prospective Observational Cohort Study

Postoperative pain remains a common clinical challenge in patients undergoing video-assisted thoracoscopic surgery (VATS), impairing early recovery and increasing opioid consumption. The serratus anterior plane block (SAPB) is a widely used regional analgesic technique for thoracic surgery, but conventional single-point injection may have limited spread of local anesthetics, resulting in suboptimal analgesia in some patients. Preliminary anatomical evidence suggests that two-point combined SAPB may achieve wider dermatomal coverage and better analgesic efficacy.

This is a single-center, prospective observational cohort study conducted at Shanghai Pulmonary Hospital, China. A total of 88 adult patients scheduled for elective unilateral VATS will be consecutively enrolled and naturally assigned to either the two-point combined SAPB group (injection at the 3rd and 5th rib levels, total 30 ml local anesthetic) or the single-point SAPB group (injection at the 5th rib level, 30 ml local anesthetic) according to routine clinical practice.

The primary outcome is the verbal rating scale (VRS) pain score on coughing at 24 hours postoperatively. Secondary outcomes include resting and dynamic pain scores at multiple time points, cumulative opioid consumption at 24 and 48 hours, incidence of postoperative nausea and vomiting, block-related complications, length of hospital stay, and Quality of Recovery-15 (QoR-15) scores. This study aims to provide clinical evidence for optimizing perioperative analgesic strategies for thoracoscopic surgery.

Study Overview

• Status: Not yet recruiting
• Conditions: Pain; Lung Cancer; Serratus Anterior Plane Block; Video-Assisted Thoracoscopic Surgery
• Intervention / Treatment: Procedure: Two-Point Serratus Anterior Plane Block; Procedure: Single-Point Serratus Anterior Plane Block

Detailed Description

Study Background Video-assisted thoracoscopic surgery (VATS) is the standard minimally invasive approach for thoracic diseases, yet over 60% of patients experience moderate-to-severe postoperative pain within 24 hours, which impairs respiratory function, increases opioid consumption and prolongs hospital stay. The serratus anterior plane block (SAPB) is a widely used fascial plane block for thoracic analgesia, but conventional single-point injection often yields inconsistent anesthetic spread due to individual anatomical variations, resulting in suboptimal analgesia in some patients. Preliminary anatomical and clinical evidence suggests that two-point combined SAPB may achieve wider dermatomal coverage and superior analgesic efficacy, but confirmatory evidence in VATS patients remains limited.

Study Design & Population This is a single-center, prospective observational cohort study conducted at Shanghai Pulmonary Hospital, China. A total of 88 eligible patients aged 18-85 years with ASA physical status I-III, scheduled for elective unilateral VATS and planned for perioperative SAPB, will be consecutively enrolled. Patients will be naturally allocated to the two-point group or single-point group according to the clinical regimen chosen by the attending anesthesiologist, with no researcher-initiated randomization. Exclusion criteria include local infection at the puncture site, allergy to amide local anesthetics, chronic opioid use, severe coagulopathy, and cognitive impairment precluding pain assessment.

Interventions & Outcomes All blocks are performed under ultrasound guidance by anesthesiologists with ≥50 prior SAPB experiences. The two-point group receives 15 ml of local anesthetic at both the 3rd and 5th rib levels (total 30 ml); the single-point group receives 30 ml at the 5th rib level. Standardized general anesthesia and postoperative analgesia protocols are applied uniformly to all patients. The primary outcome is the verbal rating scale (VRS) pain score on coughing at 24 hours postoperatively. Secondary outcomes include resting and dynamic pain scores at multiple time points, cumulative opioid consumption at 24 and 48 hours, incidence of postoperative nausea and vomiting, block-related complications, length of hospital stay, and QoR-15 recovery quality scores.

• Study Type: Observational
• Enrollment (Estimated): 88

Contacts and Locations

• Study Contact: Name: Shiyou Wei; Phone Number: 15601680288; Email: lovewishyou@tongji.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

This single-center, prospective observational cohort study is conducted at Shanghai Pulmonary Hospital, Tongji University School of Medicine, China. It enrolls adults aged 18-85 years with ASA physical status I-III, scheduled for elective unilateral video-assisted thoracoscopic surgery and planned for ultrasound-guided serratus anterior plane block as routine perioperative analgesia.Eligible participants will be consecutively enrolled after written informed consent. Patients are naturally assigned to two cohorts based on the block regimen selected by the attending anesthesiologist in standard clinical practice, with a target total sample size of 88 (~44 per cohort). No study-initiated randomization or treatment intervention is applied; all clinical management follows institutional routine protocols.

Description

Inclusion Criteria:

• Aged 18 to 85 years at enrollment, regardless of sex
• American Society of Anesthesiologists (ASA) physical status grade I to III
• Scheduled for elective unilateral video-assisted thoracoscopic surgery
• Planned to receive ultrasound-guided SAPB for routine perioperative analgesia
• Able to understand study procedures and provide written informed consent

Exclusion Criteria:

• Local infection or skin lesion at the block puncture site
• Known hypersensitivity or allergy to amide local anesthetics
• Preexisting sensory abnormality in the chest wall surgical area
• Chronic opioid use for > 3 months, history of chronic pain syndrome, or history of opioid abuse
• Severe coagulopathy (international normalized ratio > 1.5 or platelet count < 80 × 10⁹/L)
• Cognitive impairment or inability to cooperate with postoperative pain assessment
• Refusal to provide written informed consent

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Two-Point SAPB Group; Patients in this cohort receive ultrasound-guided two-point combined serratus anterior plane block for perioperative analgesia as part of routine clinical practice. A total of 30 mL local anesthetic is administered, with 15 mL injected deep to the serratus anterior muscle at the 3rd rib level and 15 mL at the 5th rib level.	Procedure: Two-Point Serratus Anterior Plane Block; Ultrasound-guided fascial plane block for perioperative thoracic analgesia. Local anesthetic is deposited deep to the serratus anterior muscle at two separate rib levels, with equal volume split between the 3rd and 5th intercostal spaces.; Other Names: Two-Point SAPB; Double-Point Serratus Plane Block
Single-Point SAPB Group; Patients in this cohort receive ultrasound-guided single-point serratus anterior plane block for perioperative analgesia as part of routine clinical practice. A total of 30 mL local anesthetic is injected deep to the serratus anterior muscle at the 5th rib level in a single administration.	Procedure: Single-Point Serratus Anterior Plane Block; Ultrasound-guided fascial plane block for perioperative thoracic analgesia. A single bolus of local anesthetic is deposited deep to the serratus anterior muscle at the 5th intercostal level.; Other Names: ingle-Point SAPB; Conventional Serratus Plane Block

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Verbal Rating Scale (VRS) Pain Score on Coughing at 24 Hours Postoperatively	Dynamic pain intensity assessed using a 0-10 verbal rating scale (0 = no pain, 10 = worst imaginable pain) when the patient performs coughing.	24 hours after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Resting Verbal Rating Scale (VRS) Pain Scores	Resting pain measured using a 0-10 verbal rating scale at multiple postoperative time points.	1 hour, 6 hours, 12 hours, 24 hours, 48 hours after surgery
Cumulative Postoperative Opioid Consumption	Total opioid consumption after surgery, converted to standard intravenous morphine equivalents.	24 hours and 48 hours after surgery
Incidence of Postoperative Nausea and Vomiting (PONV)	Proportion of patients experiencing nausea and/or vomiting within 48 hours after surgery.	Within 48 hours after surgery
Incidence of Block-Related Adverse Events	Proportion of patients with block-related complications, including pneumothorax, local hematoma, and local anesthetic toxicity.	Within 48 hours after surgery
Quality of Recovery-15 (QoR-15) Score	Patient-reported postoperative recovery quality assessed by the 15-item Quality of Recovery scale (total score range 0-150; higher score indicates better recovery quality).	24 hours and 48 hours after surgery

Collaborators and Investigators

• Sponsor: Shiyou Wei
• Investigators: Principal Investigator: Shiyou Wei, Tongji University Affiliated Shanghai Pulmonary Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): September 5, 2026

Study Registration Dates

• First Submitted: July 8, 2026
• First Submitted That Met QC Criteria: July 8, 2026
• First Posted (Actual): July 14, 2026

Study Record Updates

• Last Update Posted (Actual): July 14, 2026
• Last Update Submitted That Met QC Criteria: July 8, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neurologic Manifestations; Neoplasms by Site; Neoplasms; Respiratory Tract Diseases; Lung Diseases; Respiratory Tract Neoplasms; Thoracic Neoplasms; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain; Lung Neoplasms
• Other Study ID Numbers: 2026LY0735

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No