Comparison of effects of transversus abdominis plane block and thoracic epidural anesthesia mediated activation of inflammasome on postoperative medication, pain, and recovery in patients undergoing laparoscopic colorectal surgery.

OBJECTIVE: This work was developed to compare the effects of transversus abdominis plane block (TAPB) and thoracic epidural anesthesia (TEA) mediated activation of inflammasome on postoperative medication, pain, and recovery in patients undergoing laparoscopic colorectal surgery. Then, the effects of two anesthesia methods on postoperative analgesia of patients were investigated and compared, aiming to provide reference for the selection of postoperative analgesia methods of laparoscopy. PATIENTS AND METHODS: In this work, patients undergoing laparoscopic colorectal surgery were rolled into a TAPB group (30 patients) and a TEA group (30 patients). The blood pressure and stress indexes of the patients at different time points were observed and compared, and the doses of anesthetic drugs were recorded. Postoperative pain scores were evaluated, and postoperative recovery of the two groups was compared. Meanwhile, the peripheral venous bloods were extracted from the two groups before and after surgery for the determination of inflammasome proteins, and the detection results were compared. RESULTS: Data showed that the dose of sufentanil in TEA group was notably inferior to that in TAPB group (p<0.05). The blood pressure indexes in the TEA group decreased remarkably (p<0.05), while their changes in the TAPB group were stable. The slower point heart rate (HR), lower mean arterial pressure (MAP), and lower levels of cortisol (Cor) and norepinephrine (NE) in the TEA group were found when compared with the TAPB group during the period from pneumoperitoneum establishment to post-ventilation. After pneumoperitoneum establishment, blood oxygen saturation (SpO2) in the TEA group was lower than that in the TAPB group at the same time point (p<0.05). The postoperative visual analog scales (VAS) score and numerical rating scale (NRS) score in TEA group were lower than those in TAPB group (p<0.05). After surgery, the protein level in TEA group was significantly lower than that in TAPB group (p<0.05). CONCLUSIONS: In short, the activation of inflammasome mediated by TEA could reduce the anesthetic agents used after laparoscopic colorectal cancer surgery and reduce the surgical stress response. In addition, TEA exerted a little effect on early immunity, which was safe and feasible, contributing to postoperative analgesia and recovery. In addition, its application value in laparoscopic postoperative analgesia was higher than TAPB.

Systemic or intra-amygdala infusion of an endocannabinoid CB1 receptor antagonist AM251 blocked propofol-induced anterograde amnesia.

Propofol is well-known for its anterograde amnesic actions. However, a recent experiment showed that propofol can also produce retrograde memory enhancement effects via an interaction with the endocannabinoid CB1 system. Therefore, the authors hypothesized that the regulating effect of propofol on the endocannabinoid CB1 system might also decrease the anterograde amnesic effect of propofol under some conditions, which might be a risk factor for intraoperative awareness. Since, the basolateral amygdala (BLA) has been confirmed to mediate propofol-induced anterograde amnesia and the BLA contains a high concentration of CB1 receptors, the authors investigated whether and how the endocannabinoid system, particularly the CB1 receptor within BLA, influences propofol-induced anterograde amnesia. Male Sprague-Dawley rats trained with inhibitory avoidance (IA) were systematically pre-trained using a memory-impairing dose of propofol (25 mg/kg). Before propofol administration, rats received an intraperitoneal injection of a CB1 receptor antagonist AM251 (1 mg/kg or 2 mg/kg) or a bilateral intra-BLA injection of AM251 (0.6 ng or 6 ng per 0.5 µl). Twenty-four hours after IA training, the IA retention latency was tested. It was found that systemic or intra-BLA injection of a non-regulating dose of AM251 (2 mg/kg or 6 ng per 0.5 µl, respectively) blocked the memory-impairing effect of propofol. These results indicate that the anterograde amnesic effect of propofol is mediated, in part, by activation of the CB1 cannabinoid receptors in the BLA.