Dear Editor,

We read with great interest the recent article by Zhu et al. [1] assessing intraoperative and postoperative benefits of adding ultrasound-guided multipoint fascial plane block to total intravenous anesthesia in 80 elderly patients who underwent the combined thoracoscopic-laparoscopic esophagectomy. They showed that the addition of multipoint fascia pane block significantly decreased the dosages of drugs used for general anesthesia, improved the quality of awakening, and reduced postoperative pain without obvious adverse reactions. In addition to the limitations described by the authors in the Discussion section, however, we noted several issues in the Methods and Results sections of this study which required further clarification.

First, in the Methods section, the authors did not clearly describe whether trocar site infiltration of local anesthetic was performed in all patients. As an important component of the current enhanced recovery after surgery (ERAS) protocols for thoracoscopic or laparoscopic surgery, trocar site infiltration of local anesthetic has been shown to improve postoperative pain control with less opioid consumption and enhance postoperative recovery [2, 3]. We are concerned that an between-group imbalance in this factor would have biased Zhu et al.’s findings of postoperative outcomes.

Second, parecoxib 40 mg was immediately administered as rescue analgesic when postoperative pain visual analog scale (VAS) score was more than 4. In fact, parecoxib only is a weak analgesic and recommended as basis of multimodal postoperative analgesia protocols in the current ERAS practice. A main goal of ERAS programs is to minimize opioid use, but strong analgesics, such as opioid drugs, are often recommended as rescue analgesics for inadequate postoperative pain control [4]. We believe that different results of postoperative analgesia including the time to first rescue analgesic and  the need for rescue analgesic in the two groups would have been obtained if this study’s design included a basic analgesic package (such as paracetamol, nonsteroidal anti-inflammatory drugs, or cyclooxygenase-2-specific inhibitors) and a strong rescue analgesic for inadequate postoperative pain control according to multimodal postoperative analgesia protocols of current ERAS practice. Most important, a VAS score of 3 or less is generally considered as satisfactory postoperative pain control [5]. Thus, the current ERAS protocols recommended that analgesics should be universally titrated to minimize postoperative pain (i.e., a VAS of 3 or less) and achieve patient comfort [2, 3]. Because a trigger point of rescue analgesia with a VAS score of more than 4 was designed in this study, mean rest and dynamic pain VAS scores of controlled patients in the early postoperative period were more than 3, with large standard deviations. This indicates that a significant proportion of controlled patients experienced moderate to severe postoperative pain, especially for dynamic pain. Evidently, this is not ideal for successful use of the current ERAS protocols. Furthermore, such an inefficient control group will undoubtedly bias the findings of postoperative analgesia in favor of the intervention group.

Third, the incidences of chronic pain at 3 months and 6 months after surgery tended to increase in the control patients compared with patients receiving multipoint fascial plane block. In the Methods section, however, the authors did not clearly provide a definition of chronic pain.

Finally, in conclusion at the end of article, the authors stated that the addition of multipoint fascia plane block to total intravenous anesthesia reduced the times required to get out of bed and restore gastrointestinal function. However, we did not find that this study included these important outcomes of the current ERAS protocols. Because these important outcomes are lacking, an important question that this study cannot answer is whether the addition of multipoint fascia plane block to total intravenous anesthesia may really improve the targets of the current ERAS protocols, i.e., fast functional recovery with adequate pain control while minimizing side effects [5].