Predicting the Need for Blood Transfusions in Cardiac Surgery: A Comparison between Machine Learning Algorithms and Established Risk Scores in the Brazilian Population

ABSTRACT Introduction: Blood transfusion is a common practice in cardiac surgery, despite its well-known negative effects. To mitigate blood transfusion-associated risks, identifying patients who are at higher risk of needing this procedure is crucial. Widely used risk scores to predict the need for blood transfusions have yielded unsatisfactory results when validated for the Brazilian population. Methods: In this retrospective study, machine learning (ML) algorithms were compared to predict the need for blood transfusions in a cohort of 495 cardiac surgery patients treated at a Brazilian reference service between 2019 and 2021. The performance of the models was evaluated using various metrics, including the area under the curve (AUC), and compared to the commonly used Transfusion Risk and Clinical Knowledge (TRACK) and Transfusion Risk Understanding Scoring Tool (TRUST) scoring systems. Results: The study found that the model had the highest performance, achieving an AUC of 0.7350 (confidence interval [CI]: 0.7203 to 0.7497). Importantly, all ML algorithms performed significantly better than the commonly used TRACK and TRUST scoring systems. TRACK had an AUC of 0.6757 (CI: 0.6609 to 0.6906), while TRUST had an AUC of 0.6622 (CI: 0.6473 to 0.6906). Conclusion: The findings of this study suggest that ML algorithms may offer a more accurate prediction of the need for blood transfusions than the traditional scoring systems and could enhance the accuracy of predicting blood transfusion requirements in cardiac surgery patients. Further research could focus on optimizing and refining ML algorithms to improve their accuracy and make them more suitable for clinical use.

Validation of Blood Transfusion Risk Scores (TRACK and TRUST) in a Cardiac Surgery Service in Brazil

ABSTRACT Introduction: Transfusion of red blood cells is recurrent in cardiac surgery despite the well-established deleterious effects. Identifying patients with higher chances of requiring blood transfusion is essential to apply strategic preventive measures to reduce such chances, considering the restricted availability of this product. The most used risk scores to predict blood transfusion are the Transfusion Risk and Clinical Knowledge (TRACK) and Transfusion Risk Understanding Scoring Tool (TRUST). However, these scores were not validated for the Brazilian population. The objective of this study was to assess the accuracy of TRACK and TRUST scores in estimating the need for postoperative transfusion of red blood cell concentrates (TRBCC) after cardiac surgery. Methods: A clinical retrospective study was conducted using the database of a Brazilian reference service composed of patients operated between November 2019 and September 2021. Scores were compared using Mann-Whitney U test. Hosmer-Lemeshow goodness of fit test assessed calibration of the scores. Accuracy was assessed using the area under the receiver operating characteristic curve (AUC). All analyses considered a level of significance of 5%. The study was approved by the research ethics committee (CAAE 55577421.4.0000.5201). Results: This study assessed 498 patients. Only the TRACK score presented good calibration (P=0.238; TRUST P=0.034). AUC of TRACK was 0.678 (95% confidence interval 0.63 to 0.73; P<0.001), showing a significant accuracy. Conclusion: Between the scores analyzed, only the TRACK score showed a good calibration, but low accuracy, to predict postoperative TRBCC after cardiac surgery.

Early Outcomes of Modified De Vega Annuloplasty for Functional Tricuspid Regurgitation at a Brazilian Hospital

Abstract Background: Right valve diseases are not benign, the tricuspid regurgitation has a significant impact on morbidity and mortality of patients. Objectives: This study aimed to report the short-term results of tricuspid annuloplasty using the De Vega technique modified by Manuel Antunes. Methods: A descriptive-analytical study was performed to evaluate the results of the tricuspid valvuloplasty performed at the Instituto de Medicina Integral Professor Fernando Figueira between 2012 and 2017. Data were collected by reviewing charts and databases of the Department of Cardiology and Cardiovascular Surgery of the institution. Those with rheumatic diseases or infective endocarditis with tricuspid valve involvement, or reoperation of the tricuspid valve were excluded. Student's t-test and McNemar's were used for statistical analysis. A p-value < 0.05 was considered statistically significant. Results: A total of 87 patients were studied, most of them were women (56.3%). The most associated heart valve diseases were mitral regurgitation (27.6%) and aortic regurgitation (20.7%). There was a significant decrease in the degree of tricuspid regurgitation in the postoperative period, with 83.3% of patients with none or mild regurgitation and only 1.1% with severe regurgitation (p = 0.0077). Conclusions: In the current study, tricuspid valve annuloplasty using the modified De Vega technique was shown to be effective in the short term. Further studies are needed to evaluate the long-term results.

Embolization by Bullet Dislodged from the Heart

Abstract Embolization by a dislodged projectile is a rare complication that may occur in cases of gunshot cardiac injuries. We report a case of a firearm projectile cardiac injury that evolved, with dislocation of the projectile during cardiac surgery, into embolization of the right external carotid artery.

Influência da música na dor e na ansiedade decorrentes de cirurgia em pacientes com câncer de mama / Influence of music on pain and anxiety due to surgery in patients with breast cancer

Introdução: A ansiedade no período pré-operatório é bastante comum. Incidência de até 80 por cento tem sido relatada na literatura, em pacientes adultos. Objetivo: Avaliar a influência da música na ansiedade e na dor, em pacientes com câncer de mama que se submeteram à cirurgia. Método: Trata-se de um ensaio clínico controlado, com randomização simples. As pacientes foram divididas nos grupos: Experimental (GE) e Controle (GC). A intervenção musical foi realizada com As quatro estações de Vivaldi. Todas as pacientes foram submetidas, no pré-operatório imediato, ao Inventário de Ansiedade Traço-Estado (IDATE -Estado), sendo verificados, também, os parâmetros fisiológicos (pressão arterial, temperatura, saturação sanguínea, frequência respiratória e cardíaca). No dia seguinte, foram aplicadas as escalas de dor, em ambos os grupos. Os dados foram analisados pelo software estatístico BioEstat, versão 5.0, com nível de significância estabelecido em 5,0 por cento, sendo utilizado teste t-Student pareado. Resultados: Foram estudadas 29 pacientes, sendo 15 no GE e 14 no GC. Os parâmetros fisiológicos (FC, PAM, FR, T e SatO2) e a média das escalas de dor não apresentaram alterações significantes. Com relação ao nível de ansiedade, medido pelo escore do IDATE -Estado, houve redução significante nos níveis de ansiedade nas pacientes do grupo submetido à intervenção musical (p menor que 0,0001). Conclusão: A intervenção musical, ao reduzir o nível de ansiedade pré-operatória, mostrou-seum instrumento bom e de baixo custo para tal finalidade.

Perfil dos efeitos adversos e contra indicações dos fármacos moduladores do apetite: uma revisão sistemática / Side effects and contraindications of anti-obesity drugs: a systematic review

Anti-obesity drugs such as mazindol and beta-phenylethylamine derivatives induce their therapeutic effects by inhibiting noradrenaline and dopamine reuptake. In the hypothalamus, noradrenaline and dopamine play an important role in the control of appetite. Sibutramine reduces food intake due to a mechanism of action discretely distinct from beta-phenylethylamine products. In fact, this drug also decreases serotonin reuptake, which is a neurotransmitter quite related to satiety. Rimonabant was considered anovelty on the treatment of obesity, mainly due to its quite new mechanism of action, which is based on the blockade of CB1 receptors. Thus, considering a recent increase in the consumption of such anti-obesity drugs, this study aimed to perform a systematic review about the safety of these drugs. Based on literature, this study concluded that beta-phenylethylaminic drugs and mazindol show many side effects, mainly due to the activation of the sympathetic system (i.e. cardiovascular and gastrointestinal effects, and also central side effects, such as anxiety, and insomnia). Despite sibutramine is well tolerated by patients, clinical studies show that this drugis able to evoke similar sympathetic central and peripheral effects. Regarding rimonabant, the clinical use of this drug was linked to an increase in the incidence of major depression. In conclusion, despite most of the side effects evoked by anti-obesity drugs are classified as of low to moderate intensity, physicians must be aware of such effects upon prescription. In addition, they have to pay attention to the contraindications of such anti-obesity drugs in order to avoid health complications.

Los fármacos antiobesidad tales como el mazindoly los derivados de la beta-feniletilamina actúan inhibiendo la recaptación de la noradrenalinay de la dopamina, neurotransmisores que en el hipotálamo desenvuelven papel importante en el control del apetito. La sibutramina presenta mecanismo de acción discretamente diferente porque disminuye también la recaptación deserotonina, lo cual es positivo porque la activación del sistema serotoninérgico provoca saciedad. El rimonabanto surgió como una novedad para el tratamiento de la obesidad debido a su mecanismo de acción por medio del bloqueo de receptores cannabinoides CB1. Así, considerando el uso creciente y indiscriminado de moduladores del apetito este estudio tiene como principal objetivo realizar una revisión sistemática de la literatura sobre los efectos adversos de estos fármacos. De acuerdo con la literatura, este estudio concluyó que los fármacos beta-feniletilamínicos y el mazindol provocan varios efectos adversos derivados dela activación del sistema simpático, como sonlos efectos gastrointestinales y cardiovasculares, además de algunos efectos secundarios centrales, tales como ansiedad e insomnio. A pesar de la sibutramina ser mejor tolerada por los pacientes, los estudios clínicos muestran que este fármaco es responsable de varios efectos centrales y periféricos simpáticos. Con relación al rimonabanto, a pesar de la expectativa en relación a su mecanismo de acción innovador, su uso clínico demostró efectos adversos graves, como una depresión mayor. Enconclusión, aun cuando la mayor parte de los efectos secundarios provocados por los fármacos anti-obesidad fueron clasificados como de bajao moderada intensidad, los médicos deben estar conscientes de tales efectos secundarios en el momento de la prescripción de un fármaco anorexígeno. Además, deben estar atentos a las contra indicaciones de los tratamientos para la obesidad, a fin de evitar complicaciones mayores.

Fármacos anorexígenos como o mazindole os derivados da beta-feniletilamina ageminibindo a recaptação de noradrenalina edopamina, cujos neuro transmissores estão envolvidos em nível hipotalâmico no controle do apetite. A sibutramina possui mecanismo de ação ligeiramente diverso, pois também inibe a recaptação de serotonina, sendo um ponto positivo, visto que a ativação do sistema serotoninérgico promove a saciedade. O rimonabanto despontou como uma novidade no tratamento da obesidade, graças ao seu mecanismo de ação baseado no bloqueio de receptores canabinoides CB1. Considerando o uso crescente e indiscriminado de moduladores do apetite, o presente estudo visa fazer uma revisão sistemática da literatura sobre os efeitos adversos e as contraindicações do uso desses fármacos. Com base na literatura, este estudo concluiu que os fármacos beta-feniletilamínicos e o mazindol apresentam muitos efeitos adversos decorrentes da ativação do sistema simpático, como distúrbios gastrintestinais e cardiovasculares, além de alguns efeitos centrais, como ansiedade e insônia. Apesar de a sibutramina ser mais bem tolerada, os estudos clínicos mostram que este fármaco é também responsável por sintomas relacionados à ativação simpática periférica e a estimulação do sistema nervoso central. O rimonabanto, apesar das expectativas com relação ao seu mecanismo de ação inovador, mostrou efeitos adversos graves, como depressão maior. Em conclusão, muito embora os efeitos adversos fossem considerados de intensidade leve ou moderada, o médico precisa ter em mente tais situações no momento da prescrição de um fármaco anorexígeno. Além disso, deve estaratento às contraindicações dos tratamentos para obesidade, a fim de evitar maiores complicações.