Effect of intradiscal local anesthetic injection on intraoperative pain during percutaneous transforaminal endoscopic discectomy: A retrospective study.

OBJECTIVE: Patients undergoing percutaneous transforaminal endoscopic discectomy (PTED) often complain of unbearable intraoperative pain. This study is to observe clinical effectiveness and safety of intradiscal local anesthetic injection for intraoperative pain relief. METHODS: Total 268 patients who underwent PTED were analyzed. Patients were divided into intradiscal saline injection group (group C) and intradiscal local anesthetic injection group (group L). Intradiscal mixture was consisted of saline or local anesthetic + methylene blue, the amount of injected mixture was 3 mL. Demographic data, visual analog scale (VAS) and Quebec Back Pain Disability Scale (QBPDS) scores, mean arterial pressure (MAP) and heart rate (HR), total dosage of fentanyl, satisfaction rate of anesthesia and complications were collected at different timepoints. RESULTS: Compared with group C (3.94 ± 0.57), there was a significant reduction of VAS in group L (2.83 ± 0.28) during fibrous annular operation phase (T2). Group L had a lower total dosage of fentanyl (71 [63, 78] µg) and a higher anesthesia satisfaction rate (95.3%) than group C (82 [70, 132] µg and 73.6%, respectively) (P < 0.001). MAP and HR were lower in group L than in group C at T2 (P < 0.001). Baseline characteristics and QBPDS scores showed no meaningful intergroup differences. Four cases of complications were reported in this study. CONCLUSION: Intradiscal local anesthetic injection significantly alleviated intraoperative back pain and increased the satisfaction rate of anesthesia, without severe complications, indicating that this technique is a feasible method for intraoperative back pain relief for patients undergoing PTED.

Characterization of a novel cysteine protease in Trichinella spiralis and its role in larval intrusion, development and fecundity.

The aim of this study was to investigate the biological properties of a novel gut-specific cysteine protease in Trichinella spiralis (TsGSCP) and its role in larval intrusion, development and fecundity. TsGSCP has a functional C1 peptidase domain; C1 peptidase belongs to cathepsin B family. The TsGSCP gene cloned and expressed in Escherichia coli BL21 showed intensive immunogenicity. qPCR and Western blotting revealed that TsGSCP mRNA and protein were expressed at various T. spiralis stages, but their expression levels in intestinal infectious larvae (IIL) were clearly higher than those in muscle larvae (ML), adult worms (AWs) and new-born larvae (NBL). Indirect immunofluorescence (IIF) analysis showed that TsGSCP was primarily located at the outer cuticle and the intrauterine embryos of this parasite. rTsGSCP showed the ability to specifically bind with IECs, and the binding site is within the IEC cytoplasm. rTsGSCP accelerated larval intrusion into host intestinal epithelial cells (IECs), whereas anti-rTsGSCP antibodies suppressed larval intrusion; the acceleration and suppression was induced by rTsGSCP and anti-rTsGSCP antibodies, respectively, in a dose-dependent manner. When ML were transfected with TsGSCP-specific dsRNA, TsGSCP expression and enzymatic activity were reduced by 46.82 and 37.39%, respectively, and the capacity of the larvae to intrude into IECs was also obviously impeded. Intestinal AW burden and adult female length and fecundity were significantly decreased in the group of mice infected with dsRNA-transfected ML compared to the control dsRNA and PBS groups. The results showed that TsGSCP plays a principal role in gut intrusion, worm development and fecundity in the T. spiralis lifecycle and might be a candidate target for vaccine development against Trichinella intrusion and infection.