Influence of intraoperative remifentanil and sufentanil on sensory perception: a randomized trial

Spinal microRNA-134-5p targets glutamate receptor ionotropic kainate 3 to modulate opioid induced hyperalgesia in mice

Background: Fentanyl and its analogs are extensively used for pain relief. However, their paradoxically pronociceptive effects often lead to increased opioids consumption and risk of chronic pain. Compared to other synthetic opioids, remifentanil has been strongly linked to acute opioid hyperalgesia after exposure [remifentanil-induced hyperalgesia (RIH)]. The epigenetic regulation of microRNAs (miRNAs) on targeted mRNAs has emerged as an important pathogenesis in pain. The current research aimed at exploring the significance and contributions of miR-134-5p to the development of RIH. Methods: Both the antinociceptive and pronociceptive effects of two commonly used opioids were assessed, and miRNA expression profiles in the spinal dorsal horn (SDH) of mice acutely exposed to remifentanil and remifentanil equianalgesic dose (RED) sufentanil were screened. Next, the candidate miRNA level, cellular distribution, and function were examined by qPCR, fluorescent in situ hybridization (FISH) and Argonaute-2 immunoprecipitation. Furthermore, bioinformatics analysis, luciferase assays, miRNA overexpression, behavioral tests, golgi staining, electron microscopy, whole-cell patch-clamp recording, and immunoblotting were employed to investigate the potential targets and mechanisms underlying RIH. Results: Remifentanil induced significant pronociceptive effects and a distinct miRNA-profile from sufentanil when compared to saline controls. Among top 30 differentially expressed miRNAs spectrum, spinal miR-134-5p was dramatically downregulated in RIH mice but remained comparative in mice subjected to sufentanil. Moreover, Glutamate Receptor Ionotropic Kainate 3 (Grik3) was a target of miR-134-5p. The overexpression of miR-134-5p attenuated the hyperalgesic phenotype, excessive dendritic spine remodeling, excitatory synaptic structural plasticity, and Kainate receptor-mediated miniature excitatory postsynaptic currents (mEPSCs) in SDH resulting from remifentanil exposure. Besides, intrathecal injection of selective KA-R antagonist was able to reverse the GRIK3 membrane trafficking and relieved RIH. Conclusion: The miR-134-5p contributes to remifentanil-induced pronociceptive features via directly targeting Grik3 to modulate dendritic spine morphology and synaptic plasticity in spinal neurons.

Sufentanil ameliorates oxygen‑glucose deprivation/reoxygenation‑induced endothelial barrier dysfunction in HCMECs via the PI3K/Akt signaling pathway

Ischemic heart disease, a chronic myocardial damage disease caused by coronary artery ischemia, is the leading cause of death worldwide. The aim of the present study was to explore the efficacy of sufentanil in myocardial ischemia/reperfusion (I/R) injury. Oxygen and glucose deprivation/reoxygenation (OGD/R) was utilized to induce human cardiac microvascular endothelial cells (HCMECs) to simulate myocardial I/R injury in vitro. The Cell Counting Kit-8 assay was used to detect the effects of sufentanil on HCMECs and OGD/R-induced HCMECs. The TUNEL, lactate dehydrogenase (LDH) activity, immunofluorescence and in vitro permeability assays, were used to assess apoptosis, LDH activity, VE-cadherin protein expression levels and endothelial barrier function in OGD/R-induced HCMECs, respectively. Moreover, western blotting was performed to assess the protein expression levels of apoptosis, endothelial barrier function and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)-related proteins. The results demonstrated that sufentanil had no significant influence on the viability of HCMECs but increased the viability of OGD/R-induced HCMECs in a dose-dependent manner. Furthermore, sufentanil inhibited cell apoptosis and permeability of OGD/R-induced HCMECs but enhanced the protein expression levels of tight junction proteins, including ZO-1, Occludin, VE-cadherin and Claudin-5. Sufentanil was also demonstrated to activate the PI3K/Akt signaling pathway. In addition, the use of LY294002, an inhibitor of the PI3K/Akt signaling pathway, partially abolished the protective effects of sufentanil on apoptosis, permeability and tight junction protein expression levels. These results indicated that sufentanil ameliorated OGD/R-induced endothelial barrier dysfunction in HCMECs, potentially via the PI3K/Akt signaling pathway. The present study therefore suggested that sufentanil may serve as a novel therapeutic option for the improvement of myocardial I/R injury.

Effects of different sufentanil target concentrations on the MACBAR of sevoflurane in patients with carbon dioxide pneumoperitoneum stimulus

BACKGROUND

This study aims to observe the effects of different target controlled plasma sufentanil concentrations on the minimum alveolar concentration (MAC) of sevoflurane for blocking adrenergic response (BAR) in patients undergoing laparoscopic cholecystectomy with carbon dioxide pneumoperitoneum stimulation.

METHODS

Eighty-five patients undergoing laparoscopic cholecystectomy, aged 30-65 years, with American Society of Anesthesiologists physical status I-II, were enrolled in this study. All the patients were randomly divided into 5 groups (S₀, S₁, S₂, S₃, S₄) with different sufentanil plasma target concentration (0.0, 0.1, 0.3, 0.5, 0.7 ng ml^- 1). Anesthesia was induced by inhalation of 8% sevoflurane in 100% oxygen, and 0.6 mg kg^- 1 of rocuronium was intravenously injected to facilitate the insertion of a laryngeal mask airway. The end-tidal sevoflurane concentration and sufentanil plasma target concentration were adjusted according to respective preset value in each group. The hemodynamic response to pneumoperitoneum stimulus was observed after the end-tidal sevoflurane concentration had been maintained stable at least for 15 min. The MAC_BAR of sevoflurane was measured by a sequential method. Meanwhile, epinephrine (E) and norepinephrine (NE) concentrations in the blood were also determined before and after pneumoperitoneum stimulus in each group.

RESULTS

When the method of independent paired reversals was used, the MAC_BAR of sevoflurane in groups S₀, S₁, S₂, S₃, S₄ was 5.333% (confidence interval [CI] 95%: 5.197-5.469%), 4.533% (95% CI: 4.451-4.616%), 2.861% (95% CI: 2.752-2.981%), 2.233% (95% CI: 2.142-2.324%) and 2.139% (95% CI: 2.057-2.219%), respectively. Meanwhile, when the isotonic regression analysis was used, the MAC_BAR of sevoflurane in groups S₀, S₁, S₂, S₃, S₄ was 5.329% (95% CI: 5.321-5.343%), 4.557% (95% CI: 4.552-4.568%), 2.900% (95% CI: 2.894-2.911%), 2.216% (95% CI: 2.173-2.223%) and 2.171% (95% CI: 2.165-2.183%), respectively. The MAC_BAR was not significantly different between groups S₃ and S₄ when using 0.5 and 0.7 ng ml^- 1 of sufentanil plasma target concentrations. No significant difference was found in the change of E or NE concentration between before and after pneumoperitoneum stimulation in each group.

CONCLUSIONS

The MAC_BAR of sevoflurane can be decreased with increasing sufentanil plasma target concentrations. A ceiling effect of the decrease occurred at a sufentanil plasma target concentration of 0.5 ng ml^- 1. When the sympathetic adrenergic response was inhibited in half of the patients to pneumoperitoneum stimulation in each group, the changes of E and NE concentrations showed no significant differences.

TRIAL REGISTRATION

The study was registered at http://www.chictr.org.cn ( ChiCTR1800015819 , 23, April, 2018).

Application of dexmedetomidine combined with sufentanil in colon cancer resection and its effect on immune and coagulation function of patients

Application of dexmedetomidine combined with sufentanil in colon cancer resection and its effect on immune and coagulation function of patients was studied. Colon cancer cases (n=176) admitted to Xiangya Hospital Central South University were selected into the study. They were divided into group A (n=92) and group B (n=84). In group A, patients underwent surgery anesthesia with dexmedetomidine combined with sufentanil. In group B, patients underwent surgery anesthesia only with sufentanil. The anesthesia induced intubation, operation time and incidence of postoperative adverse reaction of patients were compared between the two groups. Heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were observed and recorded before induction, before intubation and after intubation. Blood coagulation analyzer was used to detect four items of coagulation before and after operation. FACSCalibur flow cytometry was used to detect T lymphocyte subsets in peripheral blood of patients in the two groups. The pain scores (VAS) of patients in the two groups were measured and recorded after surgery at 4, 24 and 48 h. There was a difference in anesthesia induced intubation and operation time of patients in both groups (P<0.05). There were differences in HR, SBP and DBP of patients in both groups after intubation (P<0.05), in postoperative coagulation function (P<0.05), and in postoperative immune function of patients in both groups (P<0.05). The VAS scores of patients in both groups were different at different time-points after operation (P<0.05). There were differences in postoperative adverse reactions of patients in both groups (P<0.05). Dexmedetomidine combined with sufentanil is a viable anesthetic regimen for colon cancer resection. The coagulation function and immune function have certain improvement effect for patients.

Opioid-induced hyperalgesia in clinical anesthesia practice: what has remained from theoretical concepts and experimental studies?

PURPOSE OF REVIEW

This article reviews the phenomenon of opioid-induced hyperalgesia (OIH) and its implications for clinical anesthesia. The goal of this review is to give an update on perioperative prevention and treatment strategies, based on findings in preclinical and clinical research.

RECENT FINDINGS

Several systems have been suggested to be involved in the pathophysiology of OIH with a focus on the glutaminergic system. Very recently preclinical data revealed that peripheral μ-opioid receptors (MORs) are key players in the development of OIH and acute opioid tolerance (AOT). Peripheral MOR antagonists could, thus, become a new prevention/treatment option of OIH in the perioperative setting. Although the impact of OIH on postoperative pain seems to be moderate, recent evidence suggests that increased hyperalgesia following opioid treatment correlates with the risk of developing persistent pain after surgery. In clinical practice, distinction among OIH, AOT and acute opioid withdrawal remains difficult, especially because a specific quantitative sensory test to diagnose OIH has not been validated yet.

SUMMARY

Since the immediate postoperative period is not ideal to initiate long-term treatment for OIH, the best strategy is to prevent its occurrence. A multimodal approach, including choice of opioid, dose limitations and addition of nonopioid analgesics, is recommended.