Efficacy and safety of postoperative analgesia for intercostal catheterization guided by thoracoscopy in single port thoracoscopic surgery: a prospective randomized controlled trial

Technical Summary: Efficacy and Safety of Thoracoscopy-Guided Intercostal Catheterization for Postoperative Analgesia in Single-Port VATS

Problem Statement
While single-port video-assisted thoracoscopic surgery (VATS) offers minimally invasive benefits, it still induces moderate to severe postoperative pain due to chest wall trauma, nerve injury, and muscle damage. Inadequate pain management restricts respiratory function (breathing, coughing, expectoration), leading to complications such as pneumonia, atelectasis, and delayed rehabilitation. Traditional analgesic strategies relying on intravenous (IV) opioids are associated with significant adverse effects, including dizziness, nausea, vomiting, and sedation. While thoracic epidural anesthesia is considered the "gold standard," its use is limited by risks of hemodynamic instability and anticoagulation-related complications. Although ultrasound guidance has improved single-dose nerve blocks, it lacks the ability to visualize catheter placement effectively. Consequently, there is a need for a safe, effective, and continuous regional analgesic technique that minimizes opioid-related side effects without increasing procedural risks or costs.

Methodology
This study was a prospective, randomized, single-blinded controlled trial conducted at West China Hospital involving 50 patients (aged 18–80, ASA I–III) scheduled for single-port VATS. Patients were randomized 1:1 into two groups:

1. Experimental Group (ICC): Received continuous intercostal catheterization (ICC) guided by thoracoscopy. Under direct thoracoscopic vision, a surgeon inserted an epidural needle into the deep intercostal muscle space at the T5 level. A bolus of 0.5% ropivacaine (20ml) was injected, followed by the placement of an epidural catheter. Postoperatively, patients received patient-controlled analgesia (PCA) via the catheter using 0.2% ropivacaine.
2. Control Group (IV-PCA): Received a single-dose intercostal nerve block (20ml of 0.5% ropivacaine) under thoracoscopic guidance, followed by standard intravenous opioid-based PCA. The IV PCA solution contained flurbiprofen axetil, hydromorphone, dexmedetomidine, and tropisetron.

Key Contributions and Technical Innovations

• Thoracoscopic Guidance for Catheterization: The study demonstrates the feasibility and safety of placing intercostal catheters under real-time thoracoscopic visualization. This approach allows for direct observation of the needle trajectory, catheter direction, and local anesthetic spread, effectively preventing complications such as pleural puncture or hematoma that might occur with blind or ultrasound-guided techniques in this specific context.
• Comparative Efficacy of Multimodal vs. Opioid-Centric PCA: The trial compares a regional nerve block strategy (ropivacaine-based ICC) against a multimodal IV PCA strategy (incorporating non-opioid analgesics but still utilizing opioids like hydromorphone).
• Safety Profile Assessment: The study rigorously evaluates not only pain scores but also the incidence of opioid-related adverse events (dizziness, PONV), rescue analgesia requirements, and the rate of PCA abandonment due to side effects.

Results

• Analgesic Efficacy: Both groups achieved satisfactory pain control with Numeric Rating Scale (NRS) scores remaining below 4. There was no statistically significant difference in NRS scores at rest or during coughing between the ICC and IV-PCA groups at 6–24 hours or 24–48 hours post-surgery.
• Safety and Adverse Events:
  • Procedural Safety: All ICC placements were successful with no instances of pleural perforation or hematoma.
  • Adverse Events: The ICC group demonstrated a significantly lower incidence of dizziness within the first 24 hours (20% vs. 64%, P=0.002) compared to the IV group. While the overall incidence of Postoperative Nausea and Vomiting (PONV) was lower in the ICC group, the difference was not statistically significant (20% vs. 32%, P=0.330).
  • PCA Abandonment: A significantly higher percentage of patients in the IV group abandoned their PCA pumps due to unbearable side effects (32% vs. 8%, P=0.034).
• Recovery and Economic Outcomes:
  • Quality of Recovery (QoR15): While the absolute QoR15 score at 6–24 hours was lower in the ICC group compared to the IV group (P=0.003), the decline from baseline was not significantly different between the two groups (P=0.170).
  • Clinical Outcomes: There were no significant differences in hospital length of stay, total medical costs, or the incidence of postoperative pulmonary complications (e.g., pneumonia, atelectasis) between the groups.
  • Long-term Pain: Follow-up at 3 and 6 months showed no significant difference in chronic pain scores (NRS) between the groups.

Significance and Claims
The paper concludes that ropivacaine-based intercostal catheterization guided by thoracoscopy provides an analgesic effect comparable to traditional intravenous opioid-based PCA for single-port VATS. The primary significance of this approach lies in its ability to reduce opioid-related adverse effects, specifically dizziness and the subsequent abandonment of pain management pumps, thereby improving patient compliance.

The authors assert that this technique offers a viable pain management strategy that ensures effective analgesia without increasing postoperative complications, extending hospital stays, or raising medical costs. The study emphasizes that thoracoscopic guidance enhances the safety of catheter placement, making continuous intercostal nerve block a practical alternative to systemic opioid administration in the context of Enhanced Recovery After Surgery (ERAS) protocols. The authors modestly note limitations, including the single-center design, small sample size, and single-blinded nature, suggesting that larger, multi-center trials are needed to fully validate these findings.