Background: Video-assisted thoracic surgery (VATS) is frequently associated with substantial postoperative pain, which may lead to hypopnea. Rescue analgesia using opioids has adverse effects. We aimed to evaluate the effects of rescue analgesia with serratus anterior plane block (SAPB) on moderate-to-severe pain and oxygenation in patients undergoing VATS.
Methods: Eighty patients undergoing VATS and reporting a numeric rating scale (NRS, ranging from 0-10) score of cough pain ≥4 on the first postoperative day were randomized to receive either sufentanil or SAPB for rescue analgesia. The primary outcome was the degree of relief in cough pain 30 min after rescue analgesia. Arterial oxygen pressure (PaO<inf>2</inf>), opioid consumption after rescue analgesia and the incidence of chronic pain were also assessed.
Results: The NRS scores were significantly reduced after rescue analgesia in both groups (P<inf>paired</inf> <0.001). Notably, the degree of relief in cough pain was significantly higher in the SAPB group than that in the sufentanil group (medians [interquartiles]: -3 [-4, -2] vs. -2 [-3, -1], P<0.001). Moreover, patients receiving SAPB exhibited significantly higher PaO<inf>2</inf> than those before receiving rescue analgesia (P<inf>paired</inf>=0.007). However, there were no significant differences in the PaO<inf>2</inf> before and after receiving rescue analgesia in the sufentanil group. No significant differences in opioid consumption or the incidence of chronic pain were observed between groups.
Conclusions: Rescue analgesia with SAPB on the first postoperative day had a greater effect on pain relief and oxygenation after VATS. However, its long-term effect on chronic pain requires further research.