Comparison of Patient Satisfaction between Brachial Plexus Block (Axillary Approach) and General Anesthesia for Surgical Treatment of Distal Radius Fractures: A Historical Cohort Study

Background: Distal radius fracture surgery is performed under general (GA) or regional anesthesia with brachial plexus block (NB). Whether anesthesia type affects patient outcomes is unclear. This study retrospectively compared patient satisfaction between GA and NB after surgery. Methods: This was a historical cohort study of 80 (34 GA and 46 NB) patients who underwent volar plate fixation of distal radius fractures. Propensity score analysis was used to generate a set of matched cases (NB) and controls (GA), yielding 14 matched patient-pairs. The simplified patient satisfaction scale was compared for primary outcomes. Secondary outcomes were anesthesia and surgery duration, hospital stay length, adverse events, postoperative analgesic requirement, and wrist range of motion (ROM) 2 weeks and 3 months postoperatively. Results: After propensity score matching, patients in almost all cases in both groups were “Satisfied” (effect size: 0.1, p = 0.572), indicating little significant difference. Significant differences in adverse events and postoperative analgesic use observed before matching disappeared after matching. Anesthesia duration and hospital stay length were significantly shorter in the NB group (effect size: -1.27 and -0.77, p = 0.00074 and p = 0.0388, respectively), as was surgery duration (effect size: -0.84, p = 0.0122) after matching. Similar to before matching, wrist ROM significantly improved in the NB group (effect size: 1.11, p = 0.0279) in the early postoperative period, but the difference disappeared at 3 months postoperatively. Conclusions: Patient satisfaction between distal radius fracture surgery under GA and NB was similar. Nerve block could help shorten hospital stay length and surgery duration and improve postoperative functional recovery.

Modifying oxygen tension affects bone marrow stromal cell osteogenesis for regenerative medicine

AIM To establish a hypoxic environment for promoting osteogenesis in rat marrow stromal cells(MSCs) using osteogenic matrix cell sheets(OMCSs).METHODS Rat MSCs were cultured in osteogenic media under one of four varying oxygen conditions: Normoxia(21% O_2) for 14 d(NN), normoxia for 7 d followed by hypoxia(5% O_2) for 7 d(NH), hypoxia for 7 d followed by normoxia for 7 d(HN), or hypoxia for 14 d(HH). Osteogenesis was evaluated by observing changes in cell morphology and calcium deposition, and by measuring osteocalcin secretion(ELISA) and calcium content. In vivo syngeneic transplantation using OMCSs and β-tricalcium phosphate discs, preconditioned under NN or HN conditions, was also evaluated by histology, calcium content measurements,and real-time quantitative PCR.RESULTS In the NN and HN groups, differentiated, cuboidal-shaped cells were readily observed, along with calcium deposits. In the HN group, the levels of secreted osteocalcin increased rapidly from day 10 as compared with the other groups, and plateaued at day 12(P < 0.05). At day 14, the HN group showed the highest amount of calcium deposition. In vivo, the HN group showed histologically prominent new bone formation, increased calcium deposition, and higher collagen type Ⅰ?messenger RNA expression as compared with the NN group.CONCLUSION The results of this study indicate that modifying oxygen tension is an effective method to enhance the osteogenic ability of MSCs used for OMCSs.

PM2.5-related health impacts of utilizing ammonia-hydrogen energy in Kanto Region, Japan

Ammonia has emerged as a promising hydrogen carrier with applications as an energy source in recent years. However, in addition to being toxic, gaseous ammonia is a precursor of secondary inorganic aerosols. The concentration of ambient fine particulate matter （PM2.5） is intrinsically connected to public health. In this study, PM2.5-related health impacts of utilizing ammonia-hydrogen energy in Kanto Region, Japan, were investigated. It was assumed that 20% of the electricity consumption in Kanto Region, the most populated area in Japan, was supplied by mnmonia-hydrogen energy. The PM2.5 resulted from incomplete ammonia decomposition was simulated by a chemical transport model： ADMER-PRO （modified version）. Based on the incremental PM2.5 concentration, health impacts on the elderly （individuals over 65 years old） were quantitatively evaluated. The ammonia emission in this scenario increased PM2 s by 11.7% （0.16 μg·m-3.y-1） in winter and 3.5% （0.08 μg · m-3.y-1） in summer, resulting in 351 premature deaths per year. This study suggests that cost- effective emissions control or treatment and appropriate land planning should be considered to reduce the associated health impacts of this type of energy generation. In addition, further in-depth research, including cost-benefit analysis and security standards, is needed.