Discussion
long-term opioid dependency, postoperative pain, visceral pain, ESPB, nausea and vomiting, pain, chronic pain
CHRONIC PAIN, COMPLICATIONS
This study demonstrated that ultrasound-guided bilateral ESPB reduced fentanyl requirement and postoperative pain in the patients receiving LCS. Moreover, ESPB facilitated patient ambulation and reduced hospital stay. These results suggest that ESPB can improve the quality of postoperative recovery. This is the first randomized controlled trial to investigate the effectiveness of ESPB in terms of accelerated recovery and postoperative analgesia after LCS.The most important finding in this study was the significant decrease in the postoperative opioid requirement. Opioid-sparing is one of the most essential therapeutic strategies of ERAS pathways. Increased perioperative opioid consumption may lead to opioid-related complications (e.g., nausea and vomiting) and long-term opioid dependency, which is significantly associated with the global opioid crisisEarly ambulation after colorectal surgery is essential for ERAS as it counteracts the negative physiological consequences of surgical stressUltrasound-guided ESPB in our protocol significantly reduced the postoperative pain score at every time point. In colorectal surgery, pain intensity during the first 24 after surgery is significantly correlated with the occurrence of chronic pain three to six months after surgeryThe analgesic effect of ESPB on visceral pain remains controversial; however, several recent clinical studies have provided supporting evidence for visceral pain relief by ESPBOther fascial plane blocks are also performed to reduce postoperative pain in colorectal surgery. One such plane block is the transversus abdominis plane block, a simple and popular anesthetic method for abdominal surgeryThis study may have some potential drawbacks. First, we did not determine the sensory blockade after ESPB. Determining whether the skin sensations are blocked may reveal group allocation to the physicians and patients, thereby breaking the blinding. Instead, we visually observed by ultrasound that the local anesthetics were well distributed in the target area, thereby confirming that ESPB was adequately performed. Second, the study did not include other regional blocking techniques to compare their analgesic effects. Instead, because patients in the control group received a sham block, the differences in fentanyl consumption and postoperative pain between the two groups can reflect the pain-alleviating effect of pure ESPB itself. Further research is required to explore and compare the analgesic effects of different regional anesthetic procedures (including ESPB) in colorectal surgery. Finally, the current study was performed in a single university-affiliated hospital; consequently, this may limit the generalization of the results. Furthermore, our hospital does not have an active multimodal approach to reducing perioperative opioid use. Thus, clinical data on the effects of ESPB in various perioperative settings should be investigated.