Reply to Letter to Editor titled “Comparing Analgesic Efficacy of Nerve Blocks after Thoracoscopic Surgery: Methodology Is Important”

Comparing Analgesic Efficacy of Nerve Blocks after Thoracoscopic Surgery: Methodology Is Important

We thank the authors for the valuable comments on our paper. It is a great honor to have the opportunity to discuss the methodological aspects of our study. In the following text, we present our point-by-point responses. We hope that our responses will be sufficient to dispel the doubts.

First, when the study was planned, the serratus anterior plane block (SAPB) had only just been introduced and implemented at our hospital. SAPB is routinely administered before surgery, whereas the intercostal nerve block (ICNB) is performed by the surgeon at the end of the surgery. Therefore, it was designed in the same way in this paper. We totally agree with your point regarding the preemptive analgesic effect. In another study, currently in progress at our hospital, evaluating the preemptive analgesic effect, locoregional anesthesia was decided to be administered at the same time in the two groups.

Second, in this study, we intended to compare only the effects of ICNB and SAPB as much as possible and reduce the bias of other rescue analgesia administration on the analgesic effect. Thus, the numeric rating scale was used just before the administration of rescue analgesia (ketorolac or fentanyl). Therefore, as you stated, the implementation of multimodal analgesic regimens, suggested by enhanced recovery after surgery protocols, was indeed somewhat lacking in the research process.

Third, as you suggested, after equalizing 30 mg of ketorolac with 10 mg of morphine, the two groups were compared again. The amount of rescue analgesics was significantly lower in group S than in group I (group I: 28.0 mg ± 13.5 mg, group S: 19.2 mg ± 15.5 mg; p = 0.038). However, no difference in the absolute reduction of 10 mg morphine within 24 hours was observed between the two groups. Furthermore, no difference in minimal clinically important difference (10 mg per 24 hours) was found as you expected.

Fourth, we also agree with your opinion. At the time of the study, the quality of recovery 15 questionnaire was not yet widely distributed and used in Korea, including in our hospital. Thus, researchers and patients were not familiar with it. We agree on the need to actively use it in future research.

Publication History

Received: 12 December 2021

Accepted: 08 February 2022

Article published online:
10 August 2022