Short-Term and Long-Term Effects of Ischemic Conditioning on Liver Transplantation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Although liver transplantation (LT) is one of the definitive treatments for patients with end-stage liver failure, it inevitably results in ischemic reperfusion injury. It is known that prognosis is improved when temporary ischemic conditioning (IC) is applied to patients with ischemic reperfusion injury. The objective of this meta-analysis was to determine the short-term and long-term effects of IC on the clinical outcomes of LT recipients. METHODS: Randomized controlled studies on IC in patients with LTs were included. Patients were compared between an IC group and a sham group. Studies were retrieved from PubMed, Embase, and Cochrane Library. The risk of bias was evaluated using RoB 2.0. Mortality, graft function, and major complications were synthesized using RevMan 5.4.1. RESULTS: Among 316 papers, 17 articles (1196 patients) were included. There was an insignificant increase in short-term mortality (risk ratio [RR]: 3.00, 95% CI: 0.32-28.14, P = .34). However, long-term mortality was lower in the IC group than in the sham group, but not significantly (RR: 0.75; 95% CI: 0.47-1.20, P = .23). Short-term graft function (acute graft rejection and primary graft non-function) was not improved by IC. One-year graft loss tended to show better results in the IC group (RR: 0.53, 95% CI: 0.26-1.07, P = .08). CONCLUSION: Ischemic conditioning did not have a beneficial effect on LT. Although long-term outcomes appear to be better in the IC group than in the sham group, further randomized controlled trials are needed.

Chronic exposure to dexamethasone may not affect sugammadex reversal of rocuronium-induced neuromuscular blockade: an in vivo study on rats.

BACKGROUND: Chronic glucocorticoid exposure is associated with resistance to nondepolarizing neuromuscular blocking agents. Therefore, we hypothesized that sugammadex-induced recovery would occur more rapidly in subjects exposed to chronic dexamethasone compared to those who were not exposed. This study evaluated the sugammadex-induced recovery profile after neuromuscular blockade (NMB) in rats exposed to chronic dexamethasone. METHODS: Sprague-Dawley rats were allocated to three groups (dexamethasone, control, and pair-fed group) for the in vivo study. The mice received daily intraperitoneal dexamethasone injections (500 µg/kg) or 0.9% saline for 15 days. To achieve complete NMB, 3.5 mg/kg rocuronium was administered on the sixteenth day. The recovery time to a train-of-four ratio ≥ 0.9 was measured to evaluate the complete recovery following the sugammadex injection. RESULTS: Among the groups, no significant differences were observed in the recovery time to a train-of-four ratio ≥ 0.9 following sugammadex administration (P = 0.531). The time to the second twitch of the train-of-four recovery following rocuronium administration indicated that the duration of NMB was significantly shorter in Group D than that in Groups C and P (P = 0.001). CONCLUSIONS: Chronic exposure to dexamethasone did not shorten the recovery time of sugammadex-induced NMB reversal. However, the findings of this study indicated that no adjustments to sugammadex dosage or route of administration is required, even in patients undergoing long-term steroid treatment.

Physical and chemical advances of synthetic delivery vehicles to enhance mRNA vaccine efficacy.

The successful translation of mRNA vaccines slows down the spread of viral infectious diseases, which may be accomplished by developing novel chemically modified nucleotides (or nucleosides) and highly efficient, safe mRNA delivery vehicles. Delivery vehicles protect vulnerable antigen mRNA and increase the uptake of mRNA into antigen-presenting cells in the peripheral tissue or lymph nodes. This review introduces essential characteristics of mRNA vaccines (e.g., particle sizes, colloidal stability, surface charges/endosomal escape ability, and ligand conjugation) that may be used to generate high immune responses against foreign antigens. The significance and mechanism of each characteristic are described based on the results obtained from in vitro and in vivo studies. We also discuss the development of next generation delivery vehicles for future mRNA vaccines.

Effects of etomidate use in ICU patients on ventilator therapy: a study of 12,526 patients in an open database from a single center.

BACKGROUND: There is a debate regarding the safety of etomidate. We evaluated the effects of etomidate on mortality in a large cohort of critical care patients. METHODS: This retrospective matched-cohort study was performed using the Medical Information Mart for Intensive Care version 3 (MIMIC-III) database. Among 12,526 adult patients who were prescribed etomidate or propofol on the first day of mechanical ventilation, 625 patients administered etomidate were statistically matched with 6,250 patients administered propofol. The primary outcome measures were all-cause in-hospital mortality, 48-hour survival, cardiovascular morbidity, and infectious morbidity. Logistic regression analysis with stepwise selection of variables was performed to examine the dose-mortality relationship of etomidate. RESULTS: All-cause in-hospital mortality was 1.84 times higher in the etomidate cohort (OR, 1.84; 98.75% CI, 1.42, 2.37). Compared to the propofol cohort, the etomidate cohort showed 57% lower odds of 48-hour survival (0.43 [0.27, 0.73]), no difference in odds of cardiovascular morbidity (0.86 [0.66, 1.12]), and 1.77 times higher odds of infectious morbidity (1.77 [1.35, 2.31]). Additionally, the odds of mortality increased by 1.36 times per 0.1 mg/kg of etomidate (1.36 [95% CI: 1.23, 1.49]). CONCLUSIONS: Etomidate is a poor choice as a hypnotic drug on the first day of mechanical ventilation, as it is associated with a dose-dependent increase in all-cause mortality, and does not improve survival for the first 48 h.

Does the minimal occlusive volume technique provide adequate endotracheal tube cuff pressure to prevent air leakage?: a prospective, randomized, crossover clinical study.

BACKGROUND: Methods of determining proper endotracheal tube (ETT) cuff pressure to prevent air leakage include the minimal occlusive volume (MOV) technique, which uses auscultation, and the spirometer technique, which directly measures inspiratory and expiratory breathing volumes. Spirometers may measure even small air leakage, therefore, the spirometer technique requires a higher cuff pressure than the MOV technique to completely seal the airway. This study aimed to evaluate the difference in cuff pressure between the two techniques used to seal the airway. METHODS: Thirty-five female patients were intubated using an ETT with a cuff, and cuff inflation was performed with both techniques at a 10-min interval in random order-the MOV technique and then the spirometer technique or vice versa. The cuff pressure was measured at each period. RESULTS: The cuff pressures were 16.7 ± 4.4 cmH2O and 18.7 ± 5.2 cmH2O for the MOV and spirometer techniques, respectively. The cuff pressure for the spirometer technique was 2.0 cmH2O higher than that for the MOV technique and this difference was statistically significant (95% confidence interval, 0.7-3.3; P = 0.003). Considering the upper end (3.3 cmH2O) of the 95% confidence interval and the size of one scale unit (2.0 cmH2O) of a manometer, the difference in cuff pressure was up to 4 cmH2O in practice. CONCLUSIONS: Even though the air leakage sound disappears on auscultation, unlike the previous recommendation, the airway sealing would be completed only by increasing the cuff pressure by approximately 4 cmH2O.

Accuracy of three-dimensional cephalograms generated using a biplanar imaging system.

OBJECTIVE: Biplanar imaging systems allow for simultaneous acquisition of lateral and frontal cephalograms. The purpose of this study was to compare measurements recorded on three-dimensional (3D) cephalograms constructed from two-dimensional conventional radiographs and biplanar radiographs generated using a new biplanar imaging system with those recorded on cone-beam computed tomography (CBCT)-generated cephalograms in order to evaluate the accuracy of the 3D cephalograms generated using the biplanar imaging system. METHODS: Three sets of lateral and frontal radiographs of 15 human dry skulls with prominent facial asymmetry were obtained using conventional radiography, the biplanar imaging system, and CBCT. To minimize errors in the construction of 3D cephalograms, fiducial markers were attached to anatomical landmarks prior to the acquisition of radiographs. Using the 3D Ceph™ program, 3D cephalograms were constructed from the images obtained using the biplanar imaging system (3D cephbiplanar), conventional radiography (3D cephconv), and CBCT (3D cephcbct). A total of 34 measurements were obtained compared among the three image sets using paired t-tests and Bland-Altman plotting. RESULTS: There were no statistically significant differences between the 3D cephbiplanar and 3D cephcbct measurements. In addition, with the exception of one measurement, there were no significant differences between the 3D cephcbct and 3D cephconv measurements. However, the values obtained from 3D cephconv showed larger deviations than those obtained from 3D cephbiplanar. CONCLUSIONS: The results of this study suggest that the new biplanar imaging system enables the construction of accurate 3D cephalograms and could be a useful alternative to conventional radiography.

Characteristics of the similarity index in a Korean medical journal.

BACKGROUND: Journal editors have exercised their control over submitted papers having a high similarity index. Despite widespread suspicion of possible plagiarism on a high similarity index, our study focused on the real effect of the similarity index on the value of a scientific paper. METHODS: This research examined the percent values of the similarity index from 978 submitted (420 published) papers in the Korean Journal of Anesthesiology since 2012. Thus, this study aimed to identify the correlation between the similarity index and the value of a paper. The value of a paper was evaluated in two distinct phases (during a peer-review process vs. after publication), and the value of a published paper was evaluated in two aspects (academic citation vs. social media appearance). RESULTS: Yearly mean values of the similarity index ranged from 16% to 19%. There were 254 papers cited at least once and 179 papers appearing at least once in social media. The similarity index affected the acceptance/rejection of a paper in various ways; although the influence was not linear and the cutoff measures were distinctive among the types of papers, both extremes were related to a high rate of rejection. After publication, the similarity index had no effect on academic citation or social media appearance according to the paper. CONCLUSIONS: The finding suggested that the similarity index no longer had an influence on academic citation or social media appearance according to the paper after publication, while the similarity index affected the acceptance/rejection of a submitted paper. Proofreading and intervention for finalizing the draft by the editors might play a role in achieving uniform quality of the publication.