Perineural dexmedetomidine in femoral nerve blocks increases the duration of postoperative analgesia for anterolateral thigh flap donor sites in patients with oral cancer.

Although the duration of analgesia provided by a single-shot nerve block is limited, perineural dexmedetomidine significantly enhances nerve blocks during extremity surgery. This study aimed to investigate the role of dexmedetomidine added to ropivacaine in femoral nerve blocks for postoperative analgesia of the anterolateral thigh (ALT) flap donor site in patients with oral cancer. Fifty-two participants scheduled for maxillofacial tumor resection and reconstruction using an anterolateral thigh flap were randomly allocated to either the Ropi group (femoral nerve block with ropivacaine) or the Ropi + Dex group (femoral nerve block with ropivacaine plus dexmedetomidine). The primary outcome was the duration of the sensory block, while the secondary outcomes were 24 h postoperative sufentanil use, number of patients using rescue analgesics, vital signs, postoperative pain score, incidence of agitation, and presence of adverse effects. Dexmedetomidine plus ropivacaine significantly prolonged the duration of sensory block compared with ropivacaine alone (10.4 ± 0.9 h vs 14.0 ± 1.3 h; P < 0.001). Age was positively correlated with increased duration of sensory block (r = 0.300; P = 0.033). Postoperative pain scores at the donor sites were lower in the Ropi + Dex group than in the Ropi group, at 12 h after surgery (P < 0.001). Although there were no statistically significant differences in the incidence of bradycardia between the two groups, four patients treated with dexmedetomidine experienced episodes of bradycardia. Perineural dexmedetomidine prolonged the duration of femoral nerve block and reduced postoperative pain scores at the ALT flap donor sites in patients with oral cancer.

Identifying the Risk Factors for Postoperative Sore Throat After Endotracheal Intubation for Oral and Maxillofacial Surgery.

Objective: To identify risk factors for postoperative sore throat (POST) after general anesthesia in oral and maxillOfacial surgery. Material and Methods: This study is a retrospective cohort design study. We enrolled patients with oral and maxillofacial surgery who underwent endotracheal intubation under general anesthesia in the Stomatology Hospital, Zhejiang University School Of Medicine between April 2020 and April 2021. They were divided into the POST group and the without POST group. The distribution Of various characteristics in the two groups was firstly analyzed. Then, logistic regression analysis was performed to explore the independent predictors for POST occurrence. Following this, logistic regression and random forest models were constructed and their performance was evaluated to predict POST occurrence. Results: A total of 891 participants were enrolled in the study. Female gender and cough during extubation were significantly associated with increased POST occurrence in multivariate analysis (all P <0.05). Stratified logistic regression analysis results showed that the female gender was an independent predictor for POST occurrence in the 4≤age≤14 and 1460 group after adjusting American Society of Anesthesiologists status and throat and lung disease (all P <0.05). The logistic regression model had a similar effect to the random forest model in predicting POST occurrence. Interestingly, the female gender had a higher important weight compared to the cough during extubation. Conclusion: This research reveals female gender and cough during extubation as potential risk factors for POST occurrence, which may provide guidance for the effective prevention of POST in oral and maxillofacial surgery.

Near-Infrared Mitochondria-Targetable Fluorescent Probe for High-Contrast Bioimaging of H2S.

To elucidate the complex role of biological H2S and study the mitochondrial damage and some related diseases, effective methods for visualization of H2S in mitochondria and in vivo are urgently needed. In this contribution, a novel near-infrared mitochondria-targetable fluorescence probe MI-H2S for H2S detection was developed. MI-H2S shows rapid detection ability for H2S in pure aqueous solution and outputs a highly selective and sensitive fluorescence-on signal at 663 nm with a large Stokes shift of 141 nm. Bioimaging experiments revealed that the probe has good mitochondrial-targeting ability and high-contrast imaging ability for detecting H2S in living systems. The probe also showed great potential in the detection of H2S during inflammation. All of the results demonstrate that MI-H2S can be applied as an effective probe for the visualization and study of H2S in mitochondria and in vivo.

Gender-related difference of sevoflurane postconditioning in isolated rat hearts: focus on phosphatidylinositol-3-kinase/Akt signaling.

BACKGROUND: Previous studies have reported that female gender confers cardioprotection against ischemia/reperfusion (I/R) injury, partly because estrogen activates phosphatidylinositol-3-kinase/Akt (PI3K/Akt) pathway. We have previously proven that cardioprotection of sevoflurane postconditioning is mediated by PI3K/Akt pathway in male rats. The purpose of the present study was to determine whether the cardioprotection of sevoflurane postconditioning is influenced by gender, and the role of PI3K/Akt pathway in such gender difference. MATERIALS AND METHODS: Isolated hearts from 2-mo-old male and female SD rats were subjected to ischemia for 40 min and reperfusion for 2 h in the Langendorff apparatus, and were randomly assigned to the following groups: no ischemia/reperfusion (CON), ischemia/reperfusion (I/R), I/R+sevoflurane postconditioning (I/R+SPC), I/R+100 nM wortmannin (I/R+WOR), and I/R+SPC+WOR. Postconditioning was performed with administration of 3.0% sevoflurane at the first 10 min of reperfusion. Left ventricular developed pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), and myocardial lactate dehydrogenase (LDH) release were measured. Infarct size was detected by riphenyltetrazolium chloride staining. The protein expression of total Akt (t-Akt) and phosphorylated Akt (Ser(473)) (p-Akt) were determined by Western blot. RESULTS: The I/R group showed lower LVDP and higher LVEDP than CON group in the same gender during reperfusion period. The LDH release and infarct size were smaller in the female I/R group (P < 0.05 versus male I/R group). Sevoflurane postconditioning markedly improved left ventricular function and decreased LDH, infarct size in the male I/R+SPC group (P < 0.05 versus male I/R group) but not in the female I/R+SPC group. Wortmannin abolished the cardioprotection of sevoflurane postconditioning in the male I/R+SPC+Wort group (P < 0.05 versus male I/R+SPC group), and markedly increased the infarct size and LVEDP and decreased LVDP in female rats. The t-Akt protein expression was no significant difference in all groups. The ratio of p-Akt/t-Akt expression in the male CON group was a little lower than that in the female CON group, but there was no statistical significance. In male rats, the ratio of p-Akt/t-Akt was no difference between CON and I/R group, but it was higher in I/R+SPC group than that in I/R group (P < 0.05). In female rats, the level of p-Akt was markedly increased by I/R, which was markedly higher than that in male I/R group (P < 0.05). However, p-Akt was not different between I/R and I/R+SPC groups. Wortmannin decreased the p-Akt expression in both male and female rats. CONCLUSIONS: It is concluded that female rat hearts showed greater resistance to I/R injury, and sevoflurane postconditioning developed cardioprotection in male rats but not in female rats. The PI3K/Akt pathway may be involved in the cardioprotection by both sevoflurane postconditioning and gender.