Predicting major adverse cardiovascular events after orthotopic liver transplantation using a supervised machine learning model: A cohort study.

BACKGROUND: Liver transplant (LT) patients have become older and sicker. The rate of post-LT major adverse cardiovascular events (MACE) has increased, and this in turn raises 30-d post-LT mortality. Noninvasive cardiac stress testing loses accuracy when applied to pre-LT cirrhotic patients. AIM: To assess the feasibility and accuracy of a machine learning model used to predict post-LT MACE in a regional cohort. METHODS: This retrospective cohort study involved 575 LT patients from a Southern Brazilian academic center. We developed a predictive model for post-LT MACE (defined as a composite outcome of stroke, new-onset heart failure, severe arrhythmia, and myocardial infarction) using the extreme gradient boosting (XGBoost) machine learning model. We addressed missing data (below 20%) for relevant variables using the k-nearest neighbor imputation method, calculating the mean from the ten nearest neighbors for each case. The modeling dataset included 83 features, encompassing patient and laboratory data, cirrhosis complications, and pre-LT cardiac assessments. Model performance was assessed using the area under the receiver operating characteristic curve (AUROC). We also employed Shapley additive explanations (SHAP) to interpret feature impacts. The dataset was split into training (75%) and testing (25%) sets. Calibration was evaluated using the Brier score. We followed Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis guidelines for reporting. Scikit-learn and SHAP in Python 3 were used for all analyses. The supplementary material includes code for model development and a user-friendly online MACE prediction calculator. RESULTS: Of the 537 included patients, 23 (4.46%) developed in-hospital MACE, with a mean age at transplantation of 52.9 years. The majority, 66.1%, were male. The XGBoost model achieved an impressive AUROC of 0.89 during the training stage. This model exhibited accuracy, precision, recall, and F1-score values of 0.84, 0.85, 0.80, and 0.79, respectively. Calibration, as assessed by the Brier score, indicated excellent model calibration with a score of 0.07. Furthermore, SHAP values highlighted the significance of certain variables in predicting postoperative MACE, with negative noninvasive cardiac stress testing, use of nonselective beta-blockers, direct bilirubin levels, blood type O, and dynamic alterations on myocardial perfusion scintigraphy being the most influential factors at the cohort-wide level. These results highlight the predictive capability of our XGBoost model in assessing the risk of post-LT MACE, making it a valuable tool for clinical practice. CONCLUSION: Our study successfully assessed the feasibility and accuracy of the XGBoost machine learning model in predicting post-LT MACE, using both cardiovascular and hepatic variables. The model demonstrated impressive performance, aligning with literature findings, and exhibited excellent calibration. Notably, our cautious approach to prevent overfitting and data leakage suggests the stability of results when applied to prospective data, reinforcing the model's value as a reliable tool for predicting post-LT MACE in clinical practice.

Repercussions of the Emergency neurological life support on scientific literature: a bibliometric study.

BACKGROUND: In 2012, the Neurocritical Care Society launched a compilation of protocols regarding the core issues that should be addressed within the first hours of neurological emergencies - the Emergency neurological life support (ENLS). OBJECTIVE: We aim to evaluate this repercussion through a bibliometric analysis. METHODS: We searched Scopus on October 2022 for articles mentioning ENLS. The following variables were obtained: number of citations; number of citations per year; number of publications per year; year of publication; research type; research subtype; country of corresponding author and its income category and world region; journal of publication and its 5-year impact factor (IF); and section where ENLS appeared. RESULTS: After applying eligibility criteria, we retrieved 421 articles, published from 2012 to 2022. The mean number of citations per article was 17.46 (95% Confidence Interval (CI) = 8.20-26.72), while the mean number of citations per year per article was 4.05 (95% CI = 2.50-5.61). The mean destiny journal 5-year IF was 5.141 (95% CI = 4.189-6.093). The majority of articles were secondary research (57.48%; n = 242/421) of which most were narrative reviews (71.90%; n = 174/242). High-Income countries were the most prominent (80.05%; n = 337/421 articles). There were no papers from low-income countries. There were no trials or systematic reviews from middle-income countries. CONCLUSION: Although still low, the number of publications mentioning ENLS is increasing. Articles were mainly published in journals of intensive care medicine, neurology, neurosurgery, and emergency medicine. Most articles were published by authors from high-income countries. The majority of papers were secondary research, with narrative review as the most frequent subtype.

ANTECEDENTES: Em 2012, a Neurocritical Care Society lançou uma compilação de protocolos sobre as questões centrais que devem ser abordadas nas primeiras horas de emergências neurológicas ­ Emergency neurological life support (ENLS). OBJETIVO: Avaliar a repercussão do ENLS por meio de uma análise bibliométrica. MéTODOS: A base de dados Scopus foi utilizada em outubro de 2022 para a busca por artigos mencionando o ENLS. As seguintes variáveis foram obtidas: número de citações; número de citações por ano; número de publicações por ano; ano de publicação; tipo de pesquisa; país do autor correspondente e sua categoria de renda; revista de publicação e seu fator de impacto de 5 anos (IF); e seção onde o ENLS apareceu. RESULTADOS: Os 421 artigos incluídos foram publicados de 2012 a 2022. A média de citações por artigo foi de 17.46 (intervalo de confiança (IC) 95% = 8.20­26.72), enquanto a de citações por ano por artigo foi de 4.05 (IC95% = 2.50­5.61). O IF médio por revista foi de 5.14 (IC95% = 4.19­6.09). A maioria dos artigos era de pesquisa secundária (57.48%; n = 242/421), dos quais a maioria eram revisões narrativas (71.90%; n = 174/242). Os países de alta renda foram os mais prolíficos (80.05%; n = 337/421 artigos). Não houve publicações de países de baixa ou média renda. CONCLUSãO: Embora ainda baixo, o número de publicações mencionando o ENLS vem aumentando recentemente. A maioria dos artigos foram publicados em revistas de medicina intensiva, neurologia, neurocirurgia e medicina de emergência. Artigos de pesquisa secundária foram os mais comuns, com revisões narrativas sendo o subtipo mais frequente.

Publication Trends of Research on Intrathecal Baclofen Therapy: A Bibliometric Analysis of the Literature.

OBJECTIVE: The objective of this study was to analyze the trends in publications on intrathecal baclofen (ITB) therapy. METHODS: We searched Elsevier's Scopus database in February 2022 to find articles focused on ITB therapy. Data extracted included citation count, publication year, author's country and income category, journal and its 5-year impact factor, research type, disease requiring ITB, and target population. RESULTS: The analysis covered 615 articles from 1985 to 2022. The average citation count per article was 27.47 (95% confidence interval 23.75-31.18) and the mean impact factor was 4.54 (95% confidence interval 3.84-5.24). The majority (76.42%) were primary research, with 8.1% being interventional and 91.9% observational. Even so, one half of the top ten most cited were interventional. Secondary research and case reports made up 12.68% and 10.73% respectively, with narrative reviews making up most of the secondary research (79.48%). Only 1 study conducted a meta-analysis. The United States was the most prolific country. High-income countries published 96.42% of articles. CONCLUSIONS: The rising number of ITB articles and citations indicates growing interest and expanding knowledge in this field. However, there's a notable scarcity of research from low- and middle-income countries, particularly those with high prevalence of ITB-treatable diseases. The need for more evidence to overcome potential barriers to ITB implementation is emphasized. Despite an increasing number of publications, a large proportion presented low levels of evidence, such as case reports and narrative reviews, highlighting the need for more rigorous research methods to solidify the evidence base for ITB therapy.

Repercussions of the Emergency neurological life support on scientific literature: a bibliometric study / Repercussões do Emergency neurological life support na literatura científica: um estudo bibliométrico

Abstract Background In 2012, the Neurocritical Care Society launched a compilation of protocols regarding the core issues that should be addressed within the first hours of neurological emergencies - the Emergency neurological life support (ENLS). Objective We aim to evaluate this repercussion through a bibliometric analysis. Methods We searched Scopus on October 2022 for articles mentioning ENLS. The following variables were obtained: number of citations; number of citations per year; number of publications per year; year of publication; research type; research subtype; country of corresponding author and its income category and world region; journal of publication and its 5-year impact factor (IF); and section where ENLS appeared. Results After applying eligibility criteria, we retrieved 421 articles, published from 2012 to 2022. The mean number of citations per article was 17.46 (95% Confidence Interval (CI) = 8.20-26.72), while the mean number of citations per year per article was 4.05 (95% CI = 2.50-5.61). The mean destiny journal 5-year IF was 5.141 (95% CI = 4.189-6.093). The majority of articles were secondary research (57.48%; n= 242/421) of which most were narrative reviews (71.90%; n= 174/242). High-Income countries were the most prominent (80.05%; n= 337/421 articles). There were no papers from low-income countries. There were no trials or systematic reviews from middle-income countries. Conclusion Although still low, the number of publications mentioning ENLS is increasing. Articles were mainly published in journals of intensive care medicine, neurology, neurosurgery, and emergency medicine. Most articles were published by authors from high-income countries. The majority of papers were secondary research, with narrative review as the most frequent subtype.

Resumo Antecedentes Em 2012, a Neurocritical Care Society lançou uma compilação de protocolos sobre as questões centrais que devem ser abordadas nas primeiras horas de emergências neurológicas - Emergency neurological life support (ENLS). Objetivo Avaliar a repercussão do ENLS por meio de uma análise bibliométrica. Métodos A base de dados Scopus foi utilizada em outubro de 2022 para a busca por artigos mencionando o ENLS. As seguintes variáveis foram obtidas: número de citações; número de citações por ano; número de publicações por ano; ano de publicação; tipo de pesquisa; país do autor correspondente e sua categoria de renda; revista de publicação e seu fator de impacto de 5 anos (IF); e seção onde o ENLS apareceu. Resultados Os 421 artigos incluídos foram publicados de 2012 a 2022. A média de citações por artigo foi de 17.46 (intervalo de confiança (IC) 95% = 8.20-26.72), enquanto a de citações por ano por artigo foi de 4.05 (IC95% = 2.50-5.61). O IF médio por revista foi de 5.14 (IC95% = 4.19-6.09). A maioria dos artigos era de pesquisa secundária (57.48%; n= 242/421), dos quais a maioria eram revisões narrativas (71.90%; n= 174/242). Os países de alta renda foram os mais prolíficos (80.05%; n= 337/421 artigos). Não houve publicações de países de baixa ou média renda. Conclusão Embora ainda baixo, o número de publicações mencionando o ENLS vem aumentando recentemente. A maioria dos artigos foram publicados em revistas de medicina intensiva, neurologia, neurocirurgia e medicina de emergência. Artigos de pesquisa secundária foram os mais comuns, com revisões narrativas sendo o subtipo mais frequente.

Immunotherapy in the treatment of chemoresistant gestational trophoblastic neoplasia - systematic review with a presentation of the first 4 Brazilian cases.

OBJECTIVE: To evaluate the efficacy of immunotherapy for GTN treatment after methotrexate-resistance or in cases of multiresistant disease, through a systematic review, as well as to present the first 4 Brazilian cases of immunotherapy for GTN treatment. METHODS: Three independent researchers searched five electronic databases (EMBASE, LILACS, Medline, CENTRAL and Web of Science), for relevant articles up to February/2023 (PROSPERO CRD42023401453). The quality assessment was performed using the Newcastle Ottawa scale for case series and case reports. The primary outcome of this study was the occurrence of complete remission. The presentation of the case reports was approved by the Institutional Review Board. RESULTS: Of the 4 cases presented, the first was a low-risk GTN with methotrexate resistance unsuccessfully treated with avelumab, which achieved remission with sequential multiagent chemotherapy. The remaining 3 cases were high-risk multiagent-resistant GTN that were successfully treated with pembrolizumab, among which there were two subsequent gestations, one of them with normal pregnancy and healthy conceptus. Regarding the systematic review, 12 studies were included, only one of them on avelumab, showing a 46.7% complete remission rate. The remaining 11 studies were on pembrolizumab, showing an 86.7% complete remission rate, regardless of tumor histology. Both immunotherapies showed good tolerability, with two healthy pregnancies being recorded: one after avelumb and another after pembrolizumab. CONCLUSION: Immunotherapy showed effectiveness for GTN treatment and may be especially useful in cases of high-risk disease, where pembrolizumab achieves a high therapeutic response, regardless of the histological type, and despite prior chemoresistance to multiple lines of treatment.

Machine Learning Models to Forecast Outcomes of Pituitary Surgery: A Systematic Review in Quality of Reporting and Current Evidence.

BACKGROUND: The complex nature and heterogeneity involving pituitary surgery results have increased interest in machine learning (ML) applications for prediction of outcomes over the last decade. This study aims to systematically review the characteristics of ML models involving pituitary surgery outcome prediction and assess their reporting quality. METHODS: We searched the PubMed, Scopus, and Web of Knowledge databases for publications on the use of ML to predict pituitary surgery outcomes. We used the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) to assess report quality. Our search strategy was based on the terms "artificial intelligence", "machine learning", and "pituitary". RESULTS: 20 studies were included in this review. The principal models reported in each article were post-surgical endocrine outcomes (n = 10), tumor management (n = 3), and intra- and postoperative complications (n = 7). Overall, the included studies adhered to a median of 65% (IQR = 60-72%) of TRIPOD criteria, ranging from 43% to 83%. The median reported AUC was 0.84 (IQR = 0.80-0.91). The most popular algorithms were support vector machine (n = 5) and random forest (n = 5). Only two studies reported external validation and adherence to any reporting guideline. Calibration methods were not reported in 15 studies. No model achieved the phase of actual clinical applicability. CONCLUSION: Applications of ML in the prediction of pituitary outcomes are still nascent, as evidenced by the lack of any model validated for clinical practice. Although studies have demonstrated promising results, greater transparency in model development and reporting is needed to enable their use in clinical practice. Further adherence to reporting guidelines can help increase AI's real-world utility and improve clinical practice.

Immunotherapy in the treatment of chemoresistant gestational trophoblastic neoplasia - systematic review with a presentation of the first 4 Brazilian cases

Abstract Objective To evaluate the efficacy of immunotherapy for GTN treatment after methotrexate-resistance or in cases of multiresistant disease, through a systematic review, as well as to present the first 4 Brazilian cases of immunotherapy for GTN treatment. Methods Three independent researchers searched five electronic databases (EMBASE, LILACS, Medline, CENTRAL and Web of Science), for relevant articles up to February/2023 (PROSPERO CRD42023401453). The quality assessment was performed using the Newcastle Ottawa scale for case series and case reports. The primary outcome of this study was the occurrence of complete remission. The presentation of the case reports was approved by the Institutional Review Board. Results Of the 4 cases presented, the first was a low-risk GTN with methotrexate resistance unsuccessfully treated with avelumab, which achieved remission with sequential multiagent chemotherapy. The remaining 3 cases were high-risk multiagent-resistant GTN that were successfully treated with pembrolizumab, among which there were two subsequent gestations, one of them with normal pregnancy and healthy conceptus. Regarding the systematic review, 12 studies were included, only one of them on avelumab, showing a 46.7% complete remission rate. The remaining 11 studies were on pembrolizumab, showing an 86.7% complete remission rate, regardless of tumor histology. Both immunotherapies showed good tolerability, with two healthy pregnancies being recorded: one after avelumb and another after pembrolizumab. Conclusion Immunotherapy showed effectiveness for GTN treatment and may be especially useful in cases of high-risk disease, where pembrolizumab achieves a high therapeutic response, regardless of the histological type, and despite prior chemoresistance to multiple lines of treatment.

The Author Impact Factor as a Metric to Evaluate the Impact of Neurosurgical Researchers.

OBJECTIVE: The objective of this study was to assess the Author Impact Factor (AIF) as a useful metric and as a complement to the h-index among neurosurgical researchers. METHODS: The 5-year AIF and h-index were compared among 3 groups of researchers: 1) the 100 most prolific of all time within general neurosurgical journals ("Experienced"), 2) the 100 most prolific during the 2015-2019 period within general neurosurgical journals ("Trending Group"), and 3) the 100 postgraduation year 7 neurosurgical residents with the highest h-index ("Amateur"). RESULTS: The Amateur group had a lower median h-index than the Experienced (6 vs. 55; P < 0.001) and Trending (6 vs. 43; P < 0.001) groups. The highest h-index of the Amateur group (24) was lower than the first quartile of the Experienced (46.25) and Trending (26.00) groups. The Amateur group had a lower median 5-year AIF than the Experienced (2.15 vs. 3.17; P < 0.001) and Trending (2.15 vs. 2.85; P = 0.02) groups. Unlike the h-index, the gap between the 5-year AIF distribution of the Amateur group and other groups was not profound. Although there was a positive correlation between the metrics in the 3 groups, they did not proxy for each other. For instance, while the h-index of some experienced authors that have not published recently was high, their AIFs were zero. Also, some Amateur authors published very impactful articles and had a high 5-year AIF. However, since their number of publications is inevitably low, their h-index were low. CONCLUSIONS: The AIF provides intuitive and complementary information to the h-index regarding the research output of neurosurgical authors.

Knowledge, attitudes, and behaviors regarding the use of clinical practice guidelines among spine surgeons in Latin America.

Background: Clinical Practice Guidelines (CPGs) are invaluable tools to assure evidence-based spine surgery care. In this study, we aimed to identify perceptions, barriers, and potential determinants for the use of CPG among Latin American spine surgeons. Methods: A 28-item questionnaire regarding the use of CPGs was sent to the members of AO Spine Latin America. The questionnaire was subdivided into three sections: (1) demographic data; (2) perceptions and awareness of CPGs; (3) and potential barriers to CPG use. Multivariate logistic regression was performed to assess potential associations with CPG use. Results: A total of 304 spine surgeons answered the questionnaire. Most of the participants were male (91.8%) and orthopedic spine surgeons (52.3%) who averaged 45-65 years of age. Most respondents were aware of some CPGs for spine care (68.8%) and reported using them (70.4%); lack of awareness about CPGs was the most frequent barrier to their use (65.1%). Conclusion: Awareness of CPGs in spine surgery is of paramount importance for their use. Educational programs explaining the importance and benefits of spine care CPG surgical and clinical practice would increase the adherence of physicians to the guidelines.

Demoralization, depression and anxiety in postpartum women of culturally and linguistic diverse backgrounds in Australia.

INTRODUCTION: The present study aims to investigate whether mothers from Culturally and Linguistically Diverse (CALD) backgrounds present with higher levels of demoralization in comparison with their non-minority counterparts, and to explore potential correlations between demoralization and anxiety as well as depression in the same sample of mothers. METHODS: Women admitted to a public tertiary care teaching hospital were invited to participate in the study within 24-48 hours following delivery. The study compared women who did not regard English as their main spoken language to native English-speaking women. Women were asked to complete the demographic Kissane Demoralization Scale (KDS) and Being a Mother Scale (BaM-13) questionnaires. Participants were contacted by phone, 6 to 8 weeks after they had completed the KDS and the BaM-13 questionnaires, to complete an Edinburgh Postnatal Depression Scale (EPDS) and State Trait Anxiety Scale (STAI) questionnaires. RESULTS: Mothers of CALD background presented with significantly higher scores on the KDS (p<0.001), STAI (p<0.001) and EPDS (p<0.001) scales in comparison with their non-CALD counterparts. Furthermore, when mothers were reassessed after 6 to 8 weeks, higher KDS scores in the postnatal period predicted significantly higher anxiety and depression scores, according to STAI (p<0.001) and the EPDS (p<0.001), respectively. CONCLUSIONS: The results of this study reveal that, mothers of CALD background manifest higher levels of demoralization as well as anxiety and depression in the postpartum period when compared with their non-CALD counterparts.