The median effective concentration of ropivacaine for ultrasound-guided anterior iliopsoas muscle space block in the elderly undergoing hip surgery: a dose-finding study.

Background: In order to improve perioperative pain and reduce the adverse outcome of severe pain in elderly hip fractures, anterior iliopsoas muscle space block (AIMSB) can be used clinically to reduce pain. The aim of the study is to investigate the 50% effective concentration (EC50) of ropivacaine for ultrasound-guided anterior iliopsoas space block in elderly with hip fracture. Methods: A total of 27 patients were enrolled with aged ≥65 years, American society of Anesthesiologists (ASA) physical status classification II-III and undergoing Total Hip Arthroplasty (THA). We measured the EC50 using Dixon's up-and-down method. Ultrasound-guided AIMSB was performed preoperatively with an initial concentration of 0.2% in the first patient. After a successful or unsuccessful postoperative analgesia, the concentration of local anesthetic was decreased or increased 0.05%, respectively in the next patient. The successful block effect was defined as no sensation to pinprick in the area with femoral nerve, obturator nerve, and lateral femoral cutaneous nerve in 30 min. Meanwhile, the EC50 of ropivacaine was determined by using linear model, linear-logarithmic model, probit regression model, and centered isotonic regression. Results: A total of 12 patients (48%) had a successful block. All patients with a successful block had a postoperative visual analog scale score of <4 in the 12 h. The estimated EC50 values in linear model, linear-logarithmic model, probit regression model, and centered isotonic regression (a nonparametric method) were 0.268%, 0.259%, 0.277%, and 0.289%. The residual standard error of linear model was the smallest (0.1245). Conclusion: The EC50 of ropivacaine in anterior iliopsoas space block under ultrasound guidance is 0.259-0.289%.

Effect of subanesthetic dose of esketamine on postoperative pain in elderly patients undergoing laparoscopic gastrointestinal tumor Surgery:A prospective, double-blind, randomized controlled trial.

Purpose: Postoperative pain is prevalent and severe complication in elderly surgical patients. Multiple studies propose that a small dose of esketamine administered intraoperatively can alleviate postoperative pain and curtail opioid usage. We aimed to evaluate the impact of esketamine on postoperative acute pain among elderly patients with gastrointestinal tumors. Patients and methods: This is a prospective, parallel-group, randomized controlled trial. Ninety patients aged 60 and above, undergoing resection of gastrointestinal tumors, were randomly assigned to two groups: esketamine group (Group S, a single dose of 0.25 mg/kg and 0.1 mg/kg/h infusion) and control group (Group C, saline). Visual Analogue Scale (VAS) pain scores were the primary outcome. Remifentanil consumption, instances of rescue analgesia, delirium, sleep quality, postoperative recovery quality, serum levels of inflammatory cytokines, and adverse events within 72 h post-surgery were secondary outcomes, respectively. Results: Data of 87 of 99 eligible patients were analyzed. VAS scores at rest in Group S were lower than those in Group C at 6 h [1.2 (0.6, 1.6) vs 1.6 (1.0, 2.0), P = 0.003], 12 h [1.4 (1.0, 2.0) vs 2.0 (1.5, 2.0), P < 0.001], and 24 h [1.8 (1.3, 2.0) vs 2.2 (1.6, 2.6), P < 0.001] postoperatively. At 6 h post-surgery, VAS score during coughing was lower in Group S than Group C [2.0 (2.0, 2.3) vs 2.0 (2.0, 3.0), P = 0.009]. The instances of rescue analgesia were fewer in group S compared to group C (P = 0.007). Furthermore, the esketamine group showed improved sleep quality and QoR-15 score (P < 0.05) postoperatively. Conclusion: Intravenous administration of esketamine as an adjunct to general anesthesia can decrease the intensity of pain for 24 h without additional adverse effects after laparoscopic gastrointestinal tumor surgery.

Effects of DSPP Gene Mutations on Periodontal Tissues.

Dentin sialophosphoprotein ( DSPP ) gene mutations cause autosomal dominantly inherited diseases. DSPP gene mutations lead to abnormal expression of DSPP, resulting in a series of histological, morphological, and clinical abnormalities. A large number of previous studies demonstrated that DSPP is a dentinal-specific protein, and DSPP gene mutations lead to dentin dysplasia and dentinogenesis imperfecta. Recent studies have found that DSPP is also expressed in bone, periodontal tissues, and salivary glands. DSPP is involved in the formation of the periodontium as well as tooth structures. DSPP deficient mice present furcation involvement, cementum, and alveolar bone defect. We speculate that similar periodontal damage may occur in patients with DSPP mutations. This article reviewed the effects of DSPP gene mutations on periodontal status. However, almost all of the research is about animal study, there is no evidence that DSPP mutations cause periodontium defects in patients yet. We need to conduct systematic clinical studies on DSPP mutation families in the future to elucidate the effect of DSPP gene on human periodontium.