Nefopam as a multimodal analgesia in thoracoscopic surgery: a randomized controlled trial.

Background: Video-assisted thoracoscopic surgery (VATS) is a minimally invasive procedure. However, some patients still experience severe pain after VATS. Pain after VATS can disturb deep breathing and coughing, and can increase postoperative pulmonary complications. Therefore, multidisciplinary pain management is emphasized for enhanced recovery after VATS. Nefopam is a centrally-acting, non-opioid, non-steroidal analgesic drug, and its pain reduction effect in many surgeries has been reported. We sought to determine whether administration of nefopam is effective as multimodal analgesia in VATS. Methods: This study enrolled patients aged 19 years or older, and scheduled for elective VATS lobectomy with American Society of Anesthesiologists (ASA) physical class I-III. Forty-six participants were randomly divided into a group receiving nefopam (group N), and a control group (group O) in a 1:1 ratio. The study participants, and the researcher collecting the data were blinded to the group allocation. For the group N, nefopam 20 mg was administered before surgical incision and also at the end of surgery while chest tube was inserted. For the group O, normal saline 100 mL was administered. The primary outcome of this study was the pain score, by verbal numerical rating scale, at rest and upon coughing. Results: Forty-five participants (group N =22, group O =23) were involved in the statistical analysis. Nefopam reduced pain at rest at 0 h [8 (IQR, 5-10) vs. 4 (IQR, 2-7), P=0.01], and at 0-1 h [5 (IQR, 5-8) vs. 3 (IQR, 2-5), P=0.001]. Pain upon coughing decreased with nefopam at 0 h [9 (IQR, 6-10) vs. 6 (IQR, 2-8), P=0.009], 0-1 h [6 (IQR, 5-8) vs. 5 (IQR, 2-6), P=0.001], and at 12-24 h [4 (IQR, 3-7) vs. 3 (IQR, 1-4), P=0.03]. Injection of 20 mg of nefopam before incision and at the end of surgery relieved postoperative pain at 0 h, 1 h at rest and at 0 h, 1 h, 12-24 h with coughing after VATS. Conclusions: Therefore, nefopam can serve as a useful component of multimodal analgesia for pain management after VATS. Trial Registration: ClinicalTrials.gov (NCT05173337).

A comparative study using gastric ultrasound to evaluate the safety of shortening the fasting time before pediatric echocardiography: a randomized controlled non-inferiority study.

PURPOSE: The objective of this study was to demonstrate that the gastric cross-sectional area (CSA) in the right lateral decubitus position (RLDP) during a 2-h fasting period is not larger than that during a conventional 4-h fasting period prior to pediatric echocardiography. METHODS: 93 patients aged under 3 years scheduled for echocardiography under sedation were enrolled and randomly allocated into two groups; 2-h fasting vs 4-h fasting. For group 4 h (n = 46), the patients were asked to be fasted for all types of liquid for more than 4 h, while group 2 h (n = 47) were asked to be fasted for all types of liquid for 2 h before echocardiography. Gastric ultrasound was performed before echocardiography, and CSARLDP was measured. We compared CSARLDP, incidence of at-risk stomach, fasting duration, and the incidence of major (pulmonary aspiration, aspiration pneumonia) and minor complications (nausea, retching, and vomiting, apnea, and bradycardia) between two groups. RESULTS: The mean difference of CSARLDP (group 2 h-group 4 h) was 0.49 (- 0.18 to 1.17) cm2, and it was within the non-inferiority margin (Δ = 2.1 cm2). There was no difference in the incidence of at-risk stomach (P = 0.514). There was no significant difference in the incidence of major and minor complications between the two groups. CONCLUSION: Two-hour fasting in pediatric patients who need an echocardiography did not increase major and minor complications and CSA significantly.

Effective bolus dose of remimazolam for i-gel® insertion in nonparalyzed patients: a dose-finding study.

PURPOSE: Remimazolam is a recently developed ultra-short-acting benzodiazepine used for anesthesia induction and maintenance. Nevertheless, the effective bolus dose of remimazolam for i-gel® (Intersurgical Ltd., Wokingham, Berkshire, UK) insertion without the use of neuromuscular blocking agents (NMBAs) has not been well established. METHODS: This study included 25 adult patients scheduled for surgery under general anesthesia who were eligible for i-gel use. Anesthesia was induced with predetermined bolus doses of remimazolam, starting at 0.3 mg·kg-1 for the first patient, without the use of NMBAs. All patients concurrently received remifentanil using target-controlled infusion (TCI) at a fixed effect-site concentration (Ce) of 3.0 ng·mL-1. Insertion of the i-gel was attempted 90 sec after remimazolam administration, and insertion conditions were assessed. Subsequent doses of remimazolam were decreased or increased by 0.05 mg·kg-1, depending on the success or failure of i-gel insertion. RESULTS: The mean (standard deviation) 50% effective dose (ED50) of a remimazolam bolus for successful i-gel insertion as determined by the modified Dixon's up-and-down method was 0.100 (0.027) mg·kg-1. The ED50 and ED95 estimated by isotonic regression were 0.111 (83% confidence interval [CI], 0.096 to 0.131) mg·kg-1 and 0.182 (95% CI, 0.144 to 0.195) mg·kg-1, respectively. None of the patients required treatment for hypotension or bradycardia during anesthesia induction. CONCLUSION: Based on the ED95 of remimazolam bolus dose determined in our study, we recommend using 0.182 mg·kg-1 of remimazolam in combination with remifentanil TCI at a Ce of 3.0 ng·mL-1 for successful i-gel insertion without NMBAs in adult patients. This regimen seems effective with a low risk of hemodynamic instability during anesthesia induction. STUDY REGISTRATION: ClinicalTrials.gov ( NCT05298228 ); first submitted 6 March 2022.

RéSUMé: OBJECTIF: Le remimazolam est une benzodiazépine à action ultra-courte récemment mise au point et utilisée pour l'induction et le maintien de l'anesthésie. Toutefois, la dose efficace en bolus de remimazolam pour l'insertion de l'i-gel® (Intersurgical Ltd., Wokingham, Berkshire, Royaume-Uni) sans utiliser de bloqueurs neuromusculaires (BNM) n'a pas été bien établie. MéTHODE: Cette étude a inclus 25 adultes devant bénéficier d'une intervention chirurgicale sous anesthésie générale qui étaient éligibles à l'utilisation d'un i-gel. L'anesthésie a été induite avec des doses prédéterminées en bolus de remimazolam, à partir de 0,3 mg·kg−1 pour la première personne, sans utiliser de BNM. Toutes les personnes anesthésiées ont reçu en parallèle du rémifentanil en perfusion à objectif de concentration à une concentration au site effecteur (Ce) de 3,0 ng·mL−1. L'insertion de l'i-gel a été tentée 90 secondes après l'administration de remimazolam, et les conditions d'insertion ont été évaluées. Les doses subséquentes de remimazolam ont été diminuées ou augmentées de 0,05 mg·kg−1, en fonction du succès ou de l'échec de l'insertion de l'i-gel. RéSULTATS: La dose efficace moyenne (écart type) de 50 % (DE50) d'un bolus de remimazolam pour une insertion réussie de l'i-gel, telle que déterminée par la méthode « up-and-down ¼ de Dixon modifiée, était de 0,100 (0,027) mg·kg−1. Les DE50 et DE95 estimées par régression isotonique étaient de 0,111 (intervalle de confiance [IC] à 83 %, 0,096 à 0,131) mg·kg−1 et 0,182 (IC 95 %, 0,144 à 0,195) mg·kg−1, respectivement. Aucun·e patient·e n'a eu besoin de traitement pour une hypotension ou une bradycardie pendant l'induction de l'anesthésie. CONCLUSION: D'après la DE95 de la dose de remimazolam en bolus déterminée dans notre étude, nous recommandons d'utiliser 0,182 mg·kg−1 de remimazolam en association avec une perfusion à objectif de concentration de rémifentanil à une Ce de 3,0 ng·mL−1 pour réussir l'insertion de l'i-gel sans BNM chez la patientèle adulte. Ce schéma semble efficace avec un faible risque d'instabilité hémodynamique lors de l'induction de l'anesthésie. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT05298228); première soumission le 6 mars 2022.

Dynamic Arterial Elastance as a Predictor of Supine-to-Prone Hypotension (SuProne Study): An Observational Study.

Background and Objectives: Supine-to-prone hypotension is caused by increased intrathoracic pressure and decreased venous return in the prone position. Dynamic arterial elastance (Eadyn) indicates fluid responsiveness and can be used to predict hypotension. This study aimed to investigate whether Eadyn can predict supine-to-prone hypotension. Materials and Methods: In this prospective, observational study, 47 patients who underwent elective spine surgery in the prone position were enrolled. Supine-to-prone hypotension is defined as a decrease in Mean Arterial Pressure (MAP) by more than 20% in the prone position compared to the supine position. Hemodynamic parameters, including systolic blood pressure (SAP), diastolic blood pressure, MAP, stroke volume variation (SVV), pulse pressure variation (PPV), stroke volume index, cardiac index, dP/dt, and hypotension prediction index (HPI), were collected in the supine and prone positions. Supine-to-prone hypotension was also assessed using two different definitions: MAPprone < 65 mmHg and SAPprone < 100 mmHg. Hemodynamic parameters were analyzed to determine the predictability of supine-to-prone hypotension. Results: Supine-to-prone hypotension occurred in 13 (27.7%) patients. Eadyn did not predict supine-to-prone hypotension [Area under the curve (AUC), 0.569; p = 0.440]. SAPsupine > 139 mmHg (AUC, 0.760; p = 0.003) and dP/dtsupine > 981 mmHg/s (AUC, 0.765; p = 0.002) predicted supine-to-prone hypotension. MAPsupine, SAPsupine, PPVsupine, and HPIsupine predicted MAPprone <65 mm Hg. MAPsupine, SAPsupine, SVVsupine, PPVsupine, and HPIsupine predicted SAPprone < 100 mm Hg. Conclusions: Dynamic arterial elastance did not predict supine-to-prone hypotension in patients undergoing spine surgery. Systolic arterial pressure > 139 mmHg and dP/dt > 981 mmHg/s in the supine position were predictors for supine-to-prone hypotension. When different definitions were employed (mean arterial pressure < 65 mmHg in the prone position or systolic arterial pressure < 100 mmHg in the prone position), low blood pressures in the supine position were related to supine-to-prone hypotension.

Association between body composition and chronic low back pain in Korean adults aged over 50 years: The Korea National Health and Nutrition Examination Survey (KNHANES) 2010-2011.

Background The relationship between overweight or obesity and low back pain (LBP) has previously been investigated. Several recent studies have focused on the relationship between other indicators of obesity, particularly indicators of fat and the risk of LBP. However, the results of body composition and LBP have been inconsistent. Methods All data for the present retrospective, cross-sectional study was extracted from the Korea National Health and Nutrition Examination Survey (KNHANES) versions V-1 and 2 conducted in 2010 and 2011 by the Korean Centers for Disease Control and Prevention. In KNHANES V-1 (2010) and V-2 (2011), those over 50 years of age completed the surveys on LBP, body weight, and body composition assessed using dual-energy X-ray absorptiometry (DXA) were included. The multivariable logistic regression analysis was used to examine the relationship between the presence of chronic LBP and body composition adjusting for confounders. Results We analyzed 3,579 persons who completed the question. In the multivariable analyses adjusting for age and sex, none of the variables, including fat mass and fat-free mass, remained positively or negatively associated with LBP. Additionally, when depression, smoking, alcohol intake, physical activity, diabetes mellitus, and fat or lean tissue mass were included in the multivariable logistic model, no significant associations were found between all measures of fat mass, fat-free mass, and LBP Conclusion This study is contrary to previous studies that concluded that there is a correlation between obesity and fat mass and LBP. LBP is not associated with increased levels of obesity and fat mass.

Inhibition of talin-induced integrin activation by a double-hit stapled peptide.

Integrins are ubiquitously expressed cell-adhesion proteins. Activation of integrins is triggered by talin through an inside-out signaling pathway, which can be driven by RAP1-interacting adaptor molecule (RIAM) through its interaction with talin at two distinct sites. A helical talin-binding segment (TBS) in RIAM interacts with both sites in talin, leading to integrin activation. The bispecificity inspires a "double-hit" strategy for inhibiting talin-induced integrin activation. We designed an experimental peptidomimetic inhibitor, S-TBS, derived from TBS and containing a molecular staple, which leads to stronger binding to talin and inhibition of talin:integrin interaction. The crystallographic study validates that S-TBS binds to the talin rod through the same interface as TBS. Moreover, the helical S-TBS exhibits excellent cell permeability and effectively suppresses integrin activation in cells in a talin-dependent manner. Our results shed light on a new class of integrin inhibitors and a novel approach to design multi-specific peptidomimetic inhibitors.

Differences in preoperative gastric ultrasound findings in elderly compared to the mid-aged surgical patients: A retrospective observational study.

This study aimed to compare gastric ultrasound assessments between young and elderly patients, to determine whether the cross-section area (CSA) cutoff values for elderly and young patients should be different, and to suggest CSA cutoff values for elderly patients. This study evaluated the data of 120 patients who underwent elective surgery under general anesthesia between July 2019 and August 2020. Demographic and gastric ultrasound assessment data were retrieved. Patients were divided into the elderly group (n = 58, age: ≥65 years) and young group (n = 62, age: <65 years). The CSAs in the supine and right lateral decubitus positions (RLDP), semiquantitative 3-point Perlas grade (grades 0, 1, and 2), and gastric volume (GV) were determined. CSAs according to different Perlas grades were compared between the 2 groups. To compare normally and non-normally distributed continuous data, Student t test and the Mann-Whitney U test were used, respectively. Categorical data were compared using the chi-square test or Fisher exact test, as appropriate. The receiver operating characteristic (ROC) curves were built for the CSAs to predict pulmonary aspiration. The CSA cutoff values for predicting a high risk of pulmonary aspiration in both the groups were determined. Among patients with Perlas grade 0, the CSAsupine (P = .002) and CSARLDP (P = .002) were greater in the elderly group than in the young group. The specificity, positive predictive value, and accuracy of the CSA decreased when the CSA cutoff value for the young group was applied to the elderly group. The CSA cutoff values for the elderly group were: CSAsupine, 6.92 cm2 and CSARLDP, 10.65 cm2. The CSA of the empty stomach was greater in elderly patients than in young patients. We suggest that the following CSA cutoff values should be used for predicting pulmonary aspiration risk in elderly patients: CSAsupine, 6.92 cm2 and CSARLDP, 10.65 cm2.

Predicting the risk of inappropriate depth of endotracheal intubation in pediatric patients using machine learning approaches.

Endotracheal tube (ET) misplacement is common in pediatric patients, which can lead to the serious complication. It would be helpful if there is an easy-to-use tool to predict the optimal ET depth considering in each patient's characteristics. Therefore, we plan to develop a novel machine learning (ML) model to predict the appropriate ET depth in pediatric patients. This study retrospectively collected data from 1436 pediatric patients aged < 7 years who underwent chest x-ray examination in an intubated state. Patient data including age, sex, height weight, the internal diameter (ID) of the ET, and ET depth were collected from electronic medical records and chest x-ray. Among these, 1436 data were divided into training (70%, n = 1007) and testing (30%, n = 429) datasets. The training dataset was used to build the appropriate ET depth estimation model, while the test dataset was used to compare the model performance with the formula-based methods such as age-based method, height-based method and tube-ID method. The rate of inappropriate ET location was significantly lower in our ML model (17.9%) compared to formula-based methods (35.7%, 62.2%, and 46.6%). The relative risk [95% confidence interval, CI] of an inappropriate ET location compared to ML model in the age-based, height-based, and tube ID-based method were 1.99 [1.56-2.52], 3.47 [2.80-4.30], and 2.60 [2.07-3.26], respectively. In addition, compared to ML model, the relative risk of shallow intubation tended to be higher in the age-based method, whereas the risk of the deep or endobronchial intubation tended to be higher in the height-based and the tube ID-based method. The use of our ML model was able to predict optimal ET depth for pediatric patients only with basic patient information and reduce the risk of inappropriate ET placement. It will be helpful to clinicians unfamiliar with pediatric tracheal intubation to determine the appropriate ET depth.

Body Map of Droplet Distributions During Oropharyngeal Suction to Protect Health Care Workers From Airborne Diseases.

PURPOSE: Health care workers (HCWs), and in particular anesthesia providers, often must perform aerosol-generating medical procedures (AGMPs). However, no studies have analyzed droplet distributions on the bodies of HCWs during AGMPs. Therefore, the purpose of this study was to assess and analyze droplet distributions on the bodies of HCWs during suction of oral cavities with and without oral airways and during extubations. DESIGN: Using a quasi-experiemental design, we assumed the HCWs perform suction and extubation on intubated patients, and we prepared an intubated mannequin mimicking a patient. This study performed the oral suction and extubation on the intubated mannequin (with or without oral airways in place) and analyzed the droplet distributions. METHODS: We prepared a mannequin intubated with an 8.0 mm endotracheal tube, assuming the situation of general anesthesia. We designed the body mapping gown, and divided it into 10 areas including the head, neck, chest, abdomen, upper arms, forearms, and hands. We classified experiments into group O when suctions were performed on the mannequin with an oral airway, and into group X when the suctions were performed on the mannequin without an oral airway. An experienced board-certified anesthesiologist performed 10 oral suctions on each mannequin, and 10 extubations. We counted the droplets on the anesthesiologist's gown according to the divided areas after each procedure. FINDINGS: The mean droplet count after suction was 6.20 ± 2.201 in group O and 13.6 ± 4.300 in group X, with a significant difference between the two groups (P < .001). The right and left hands were the most contaminated areas in group O (2.8 ± 1.033 droplets and 2.0 ± 0.943 droplets, respectively). The abdomen, right hand, left forearm, and left hand showed many droplets in group X. (1.3 ± 1.337 droplets, 3.1 ± 1.792 droplets, 3.2 ± 3.910 droplets, and 4.3 ± 2.214 droplets, respectively). The chest, abdomen, and left hand presented significantly more droplets in group X than in group O. The trunk area (chest and abdomen) was exposed to more droplets during extubations than during suctions. CONCLUSIONS: During suctions, more droplets are splattered from mannequins without oral airways than from those with oral airways. The right and left hands were the most contaminated areas in group O. Moreover, the abdomen, right hand, left forearm, and left hand presented a lot of droplets in group X. In addition, extubations contaminate wider areas (the head, neck, chest and abdomen) of an HCW than suctions.

Machine learning for prediction of postoperative nausea and vomiting in patients with intravenous patient-controlled analgesia.

BACKGROUND: Postoperative nausea and vomiting (PONV) is a still highly relevant problem and is known to be a distressing side effect in patients. The aim of this study was to develop a machine learning model to predict PONV up to 24 h with fentanyl-based intravenous patient-controlled analgesia (IV-PCA). METHODS: From July 2019 and July 2020, data from 2,149 patients who received fentanyl-based IV-PCA for analgesia after non-cardiac surgery under general anesthesia were applied to develop predictive models. The rates of PONV at 1 day after surgery were measured according to patient characteristics as well as anesthetic, surgical, or PCA-related factors. All statistical analyses and computations were performed using the R software. RESULTS: A total of 2,149 patients were enrolled in this study, 337 of whom (15.7%) experienced PONV. After applying the machine-learning algorithm and Apfel model to the test dataset to predict PONV, we found that the area under the receiver operating characteristic curve using logistic regression was 0.576 (95% confidence interval [CI], 0.520-0.633), k-nearest neighbor was 0.597 (95% CI, 0.537-0.656), decision tree was 0.561 (95% CI, 0.498-0.625), random forest was 0.610 (95% CI, 0.552-0.668), gradient boosting machine was 0.580 (95% CI, 0.520-0.639), support vector machine was 0.649 (95% CI, 0.592-0.707), artificial neural network was 0.686 (95% CI, 0.630-0.742), and Apfel model was 0.643 (95% CI, 0.596-0.690). CONCLUSIONS: We developed and validated machine learning models for predicting PONV in the first 24 h. The machine learning model showed better performance than the Apfel model in predicting PONV.

Oxygen reserve index guided fraction of inspired oxygen titration to reduce hyperoxemia during laparoscopic gastrectomy: A randomized controlled trial.

BACKGROUND: The usefulness of the oxygen reserve index (ORi) in reducing hyperoxemia remains unclear. We designed this study to investigate whether fraction of inspired oxygen (FiO2) adjustment under a combination of ORi and peripheral oxygen saturation (SpO2) guidance can reduce intraoperative hyperoxemia compared to SpO2 alone. METHODS: In this prospective, double-blind, randomized controlled study, we allocated patients scheduled for laparoscopic gastrectomy to the SpO2 group (FiO2 adjusted to target SpO2 ≥ 98%) or the ORi-SpO2 group (FiO2 adjusted to target 0 < 0 ORi < .3 and SpO2 ≥ 98%). The ORi, SpO2, FiO2, arterial partial pressure of oxygen (PaO2), and incidence of severe hyperoxemia (PaO2 ≥ 200 mm Hg) were recorded before and 1, 2, and 3 hours after surgical incision. Data from 32 and 30 subjects in the SpO2 and ORi-SpO2 groups, respectively, were analyzed. RESULTS: PaO2 was higher in the SpO2 group (250.31 ± 57.39 mm Hg) than in the ORi-SpO2 group (170.07 ± 49.39 mm Hg) 1 hour after incision (P < .001). PaO2 was consistently higher in the SpO2 group than in the ORi-SpO2 group, over time (P = .045). The incidence of severe hyperoxemia was higher in the SpO2 group (84.4%) than in the ORi-SpO2 group (16.7%, P < .001) 1 hour after incision. Higher FiO2 was administered to the SpO2 group [52.5 (50-60)] than the ORi-SpO2 group [40 (35-50), P < .001] 1 hour after incision. SpO2 was not different between the 2 groups. CONCLUSION: The combination of ORi and SpO2 guided FiO2 adjustment reduced hyperoxemia compared to SpO2 alone during laparoscopic gastrectomy.

Individual- and School-level Predictors of Latent Profiles of Bullying Victimization: Comparing South Korea and the United States.

This cross-national research investigated nationally representative adolescents from South Korea and the United States, explored similarities and differences in latent profiles of bullying victimization between countries, and examined individual- and school-level variables that predict such latent profiles supported by the Social Disorganization Theory. The fourth-grade sample of the 2015 Trends in International Mathematics and Science Study from South Korea (N = 4,669) and the United States (N = 10,029) was used to conduct a latent profile analysis based on eight items of the bullying victimization questionnaire. Multilevel logistic regression was conducted using latent profiles as dependent variables. Independent variables include individual-level (material goods, school absence, academic interest, school belonging) and school-level (concentration of affluent families, school resources, the severity of delinquency, academic commitment) factors. More similarities existed than differences in the latent groups of bullying victimization between South Korea (rare, low-moderate, verbal-relational-physical, and multi-risk) and the United States (rare, low-moderate, verbal-relational, and multi-risk). Evidence for school-level variables as predictors of bullying victimization profiles was stronger for adolescents in the United States, with a concentration of affluent families and severity of delinquency being significant in four of the six models. For the South Korean sample, the severity of delinquency predicted bullying victimization in only one model. Examination of both individual- and school-level factors that predict unique bullying victimization experiences grounded in Social Disorganization Theory may be informative for addressing key areas of intervention-especially at the school-level context in which victimization primarily takes place and where anti-bullying intervention programs are often provided.

Effect of spironolactone use in pulmonary arterial hypertension - analysis from pivotal trial databases.

Spironolactone, a common diuretic used in the treatment of pulmonary arterial hypertension (PAH), improves cardiopulmonary hemodynamics by attenuating the adverse effects of hyperaldosteronism on endothelin type-B receptor function within pulmonary endothelial cells. Spironolactone has demonstrated vascular remodeling properties and reduced all-cause mortality in patients with severe heart failure. Despite widespread use, however, its effect on morbidity and mortality in PAH has not been fully explored. A large cohort of PAH patients from a harmonized dataset from four pivotal trials were analyzed to characterize the patient population and outcomes associated with spironolactone treatment. Of 1229 evaluable patients, 74% were female, mean age of 47 ± 15 years, baseline six-minute walk distance (6MWD) 345 ± 74 m and 75% were World health Organization (WHO) functional class (FC) III/IV. Of the patients receiving spironolactone, 43% were on subcutaneous treprostinil, compared to 29.9% of those patients who were not receiving spironolactone. Long-term spironolactone-treated PAH patients were older (p = 0.01), had lower baseline 6MWD (p = 0.01) and cardiac index (p < 0.01), higher baseline Borg dyspnea score (p = 0.01), WHO functional class, and right arterial pressure (p < 0.01). Additionally, spironolactone-treated patients tended to have higher hazard of clinical worsening (p < 0.01). A propensity analysis was performed and when controlled for disease severity, revealed that spironolactone-treated patients did not demonstrate improved outcomes in terms of survival and clinical worsening. Across studies, the current analysis has demonstrated that the actions of spironolactone within the context of the PAH disease process may differ from its action in CHF patients. Despite reported outcomes of spironolactone use in patients with left heart disease, these findings may not translate to right heart failure and pulmonary vascular pathology, as similar outcomes have not necessarily been recognized in the PAH patient population. Future studies are needed to explore these findings further.

Machine Learning Approaches to Predict Chronic Lower Back Pain in People Aged over 50 Years.

Background and Objectives: Chronic lower back pain (LBP) is a common clinical disorder. The early identification of patients who will develop chronic LBP would help develop preventive measures and treatment. We aimed to develop machine learning models that can accurately predict the risk of chronic LBP. Materials and Methods: Data from the Sixth Korea National Health and Nutrition Examination Survey conducted in 2014 and 2015 (KNHANES VI-2, 3) were screened for selecting patients with chronic LBP. LBP lasting >30 days in the past 3 months was defined as chronic LBP in the survey. The following classification models with machine learning algorithms were developed and validated to predict chronic LBP: logistic regression (LR), k-nearest neighbors (KNN), naïve Bayes (NB), decision tree (DT), random forest (RF), gradient boosting machine (GBM), support vector machine (SVM), and artificial neural network (ANN). The performance of these models was compared with respect to the area under the receiver operating characteristic curve (AUROC). Results: A total of 6119 patients were analyzed in this study, of which 1394 had LBP. The feature selected data consisted of 13 variables. The LR, KNN, NB, DT, RF, GBM, SVM, and ANN models showed performances (in terms of AUROCs) of 0.656, 0.656, 0.712, 0.671, 0.699, 0.660, 0.707, and 0.716, respectively, with ten-fold cross-validation. Conclusions: In this study, the ANN model was identified as the best machine learning classification model for predicting the occurrence of chronic LBP. Therefore, machine learning could be effectively applied in the identification of populations at high risk of chronic LBP.

Gastric emptying of preoperative carbohydrate in elderly assessed using gastric ultrasonography: A randomized controlled study.

BACKGROUND: Preoperative carbohydrate loading enhances postoperative recovery and reduces patient discomfort. However, gastric emptying of liquids can be delayed in elderly populations. Therefore, this study aimed to evaluate the gastric emptying of 400 mL of a carbohydrate drink ingested 2 hours before surgery in elderly patients. METHODS: In this prospective, randomized controlled study, patients aged >65 years were allocated to either fast from midnight (nil per os [NPO] group, n = 29) or drink 400 mL of a carbohydrate drink 2 hours before surgery (carbohydrate group, n = 29). The gastric antrum was assessed using ultrasonography in the supine position, followed by the right lateral decubitus (RLD) position. The gastric antrum was graded as grade 0 (fluid not seen in both positions), grade 1 (fluid only seen in the RLD position), and grade 2 (fluid seen in both positions). The gastric antral cross-sectional area (CSA) and aspirated residual gastric volume were measured. RESULTS: In 58 patients, the incidence of grade 2 stomach was 13.8% in NPO group and 17.2% in carbohydrate group (P = .790). The gastric antral CSA in the supine position was larger in carbohydrate group than in NPO group (4.42 [3.72-5.18] cm2 vs 5.31 [4.35-6.92] cm2, P = .018). The gastric antral CSA in the RLD position was not different in NPO and carbohydrate groups (P = .120). There was no difference in gastric volume (2 [0-7.5] vs 3 [0-13.4], P = .331) in NPO group versus carbohydrate group. CONCLUSION: The incidence of grade 2 stomach was not different between NPO group and carbohydrate group in elderly patients.

Machine learning model for predicting the optimal depth of tracheal tube insertion in pediatric patients: A retrospective cohort study.

OBJECTIVE: To construct a prediction model for optimal tracheal tube depth in pediatric patients using machine learning. METHODS: Pediatric patients aged <7 years who received post-operative ventilation after undergoing surgery between January 2015 and December 2018 were investigated in this retrospective study. The optimal location of the tracheal tube was defined as the median of the distance between the upper margin of the first thoracic(T1) vertebral body and the lower margin of the third thoracic(T3) vertebral body. We applied four machine learning models: random forest, elastic net, support vector machine, and artificial neural network and compared their prediction accuracy to three formula-based methods, which were based on age, height, and tracheal tube internal diameter(ID). RESULTS: For each method, the percentage with optimal tracheal tube depth predictions in the test set was calculated as follows: 79.0 (95% confidence interval [CI], 73.5 to 83.6) for random forest, 77.4 (95% CI, 71.8 to 82.2; P = 0.719) for elastic net, 77.0 (95% CI, 71.4 to 81.8; P = 0.486) for support vector machine, 76.6 (95% CI, 71.0 to 81.5; P = 1.0) for artificial neural network, 66.9 (95% CI, 60.9 to 72.5; P < 0.001) for the age-based formula, 58.5 (95% CI, 52.3 to 64.4; P< 0.001) for the tube ID-based formula, and 44.4 (95% CI, 38.3 to 50.6; P < 0.001) for the height-based formula. CONCLUSIONS: In this study, the machine learning models predicted the optimal tracheal tube tip location for pediatric patients more accurately than the formula-based methods. Machine learning models using biometric variables may help clinicians make decisions regarding optimal tracheal tube depth in pediatric patients.

Text Mining Approaches to Analyze Public Sentiment Changes Regarding COVID-19 Vaccines on Social Media in Korea.

The COVID-19 pandemic has affected the entire world, resulting in a tremendous change to people's lifestyles. We investigated the Korean public response to COVID-19 vaccines on social media from 23 February 2021 to 22 March 2021. We collected tweets related to COVID-19 vaccines using the Korean words for "coronavirus" and "vaccines" as keywords. A topic analysis was performed to interpret and classify the tweets, and a sentiment analysis was conducted to analyze public emotions displayed within the retrieved tweets. Out of a total of 13,414 tweets, 3509 were analyzed after preprocessing. Eight topics were extracted using the Latent Dirichlet Allocation model, and the most frequently tweeted topic was vaccine hesitation, consisting of fear, flu, safety of vaccination, time course, and degree of symptoms. The sentiment analysis revealed a similar ratio of positive and negative tweets immediately before and after the commencement of vaccinations, but negative tweets were prominent after the increase in the number of confirmed COVID-19 cases. The public's anticipation, disappointment, and fear regarding vaccinations are considered to be reflected in the tweets. However, long-term trend analysis will be needed in the future.

Gastric Ultrasound Assessing Gastric Emptying of Preoperative Carbohydrate Drinks: A Randomized Controlled Noninferiority Study.

BACKGROUND: Tools for the evaluation of gastric emptying have evolved over time. The purpose of this study was to show that the risk of pulmonary aspiration is not increased with carbohydrate drink, by demonstrating that the gastric antral cross-sectional area (CSA) of the NO-NPO group is either equivalent to or less than that of the NPO (nil per os) group. METHODS: Sixty-four patients scheduled for elective laparoscopic benign gynecologic surgery were enrolled and randomly assigned to the NPO group (n = 32) or the NO-NPO group (n = 32). After having a regular meal until midnight before surgery, the NPO group fasted until surgery, while the NO-NPO group ingested 400 mL of a carbohydrate drink at midnight and freely up to 2 hours before anesthesia. The primary outcome was the gastric antral CSA by gastric ultrasound in right lateral decubitus position (RLDP). Noninferiority was defined as a mean difference of CSA <2.8 cm2. Secondary outcomes included CSA in supine position, gastric volume (GV), GV per weight (GV/kg), GV/kg >1.5 mL/kg, and Perlas grade. RESULTS: CSA in RLDP was not different between the NPO group (6.25 ± 3.79 cm2) and the NO-NPO group (6.21 ± 2.48 cm2; P = .959). The mean difference of CSA in RLDP (NO-NPO group - NPO group) was 0.04 (95% confidence interval [CI], -1.56 to 1.64), which was within the noninferiority margin of 2.8 cm2. CSA was not different between the 2 groups (4.17 ± 2.34 cm2 in NPO group versus 4.28 ± 1.23 cm2 in NO-NPO group; P = .828). GV in NPO group (70 ± 56 mL) was not different from NO-NPO group (66 ± 36 mL; mean difference, 3.66; 95% CI, -20 to 27; P = .756). GV/kg in the NPO group (1.25 ± 1.00 mL/kg) was not different from the NO-NPO group (1.17 ± 0.67 mL/kg; P = .694). The incidence of GV/kg > 1.5 mL/kg was not different between NPO (31.3%) and NO-NPO group (21.9%; P = .768). The median (interquartile range) of the Perlas grade was 1 (0-1) in NPO group and 0.5 (0-1) in NO-NPO group (P = .871). CONCLUSIONS: Preoperative carbohydrates ingested up to 2 hours before anesthesia do not delay gastric emptying compared to midnight fasting, as evaluated with gastric ultrasound.

Phosphorylation of RIAM by src promotes integrin activation by unmasking the PH domain of RIAM.

Integrin activation controls cell adhesion, migration, invasion, and extracellular matrix remodeling. RIAM (RAP1-GTP-interacting adaptor molecule) is recruited by activated RAP1 to the plasma membrane (PM) to mediate integrin activation via an inside-out signaling pathway. This process requires the association of the pleckstrin homology (PH) domain of RIAM with the membrane PIP2. We identify a conserved intermolecular interface that masks the PIP2-binding site in the PH domains of RIAM. Our data indicate that phosphorylation of RIAM by Src family kinases disrupts this PH-mediated interface, unmasks the membrane PIP2-binding site, and promotes integrin activation. We further demonstrate that this process requires phosphorylation of Tyr267 and Tyr427 in the RIAM PH domain by Src. Our data reveal an unorthodox regulatory mechanism of small GTPase effector proteins by phosphorylation-dependent PM association of the PH domain and provide new insights into the link between Src kinases and integrin signaling.