Receiver operating characteristic (ROC) to determine cut-off points of clinical and biomolecular markers to discriminate mortality in severe COVID-19 living at high altitude.

BACKGROUND: In 2020, Ecuador had one of the highest death rates because of COVID-19. The role of clinical and biomolecular markers in COVID disease prognosis, is still not well supported by available data. In order for these markers to have practical application in clinical decision-making regarding patient treatment and prognosis, it is necessary to know an optimal cut-off point, taking into consideration ethnic differences and geographic conditions. AIM: To determine the value of clinical and biomolecular markers, to predict mortality of patients with severe COVID-19 living at high altitude. METHODS: In this study, receiver operating characteristic (ROC) curves, area under the curve (AUC) of ROC, sensitivity, specificity and likelihood ratios were calculated to determine levels of clinical and biomolecular markers that best differentiate survivors versus non-survivors in severe COVID subjects that live at a high altitude setting. RESULTS: Selected cut-off values for ferritin (≥ 1225 ng/dl, p = 0.026), IL-6 (≥ 11 pg/ml, p = 0.005) and NLR (≥ 22, p = 0.008) at 24 h, as well as PaFiO2 (≤ 164 mmHg, p = 0.015), NLR (≥ 16, p = p = 0.013) and SOFA (≥ 6, p = 0.031) at 72 h, appear to have good discriminating power to differentiate survivors versus non-survivors. Additionally, odds ratios for ferritin (OR = 3.38); IL-6 (OR = 17.07); PaFiO2 (OR = 4.61); NLR 24 h (OR = 4.95); NLR 72 h (OR = 4.46), and SOFA (OR = 3.77) indicate increased risk of mortality when cut-off points were taken into consideration. CONCLUSIONS: We proposed a straightforward and understandable method to identify dichotomized levels of clinical and biomolecular markers that can discriminate between survivors and non-survivors patients with severe COVID-19 living at high altitudes.

Microbiota y sepsis

La sepsis es la respuesta desordenada del organismo a la infección y se caracteriza por un daño a los órganos que puede ser irreversible y mortal. El microbioma intestinal regula a un grupo de mecanismos homeostáticos en el huésped, como la función inmunológica y la protección de la barrera intestinal, la pérdida de la estructura y la función microbiana intestinal normal; además, se ha asociado con el inicio de enfermedades de características diversas. La evidencia reciente ha demostrado un nexo entre el microbioma intestinal y la sepsis: la alteración del microbioma intestinal aumenta la susceptibilidad a la sepsis a través de varios mecanismos como la expansión de bacterias intestinales patógenas, la respuesta proinflamatoria marcada y la disminución de la formación de productos microbianos beneficiosos como los ácidos grasos de cadena corta. Una vez establecida la sepsis, la alteración del microbioma intestinal empeora y aumenta la susceptibilidad a la disfunción del órgano terminal. Existen pruebas limitadas de que las terapias basadas en microbiomas (que incluyen a probióticos y a la descontaminación digestiva selectiva) pueden disminuir el riesgo de sepsis y mejorar sus resultados en poblaciones de pacientes seleccionadas, pero las preocupaciones sobre la seguridad causan una aceptación limitada. Si bien gran parte de la evidencia que vincula el microbioma intestinal y la sepsis se ha establecido en estudios preclínicos, aún es necesaria la evidencia clínica en distintas áreas.

Sepsis is the body's overwhelming response to an infection. It is characterized by damage to the organs that may be irreversible and life-threatening. The gastrointestinal microbiome regulates a series of homeostatic mechanisms in the host, such as the immune function and the protection of the intestinal barrier, and the loss of normal intestinal microbial structure and function. Moreover, it has been associated with the onset of diseases of diverse characteristics. Recent evidence has shown a link between the gastrointestinal microbiome and sepsis: the alteration of the gastrointestinal microbiome increases the susceptibility to sepsis through various mechanisms, including the expansion of pathogenic intestinal bacteria, marked pro-inflammatory response and decreased production of beneficial microbial products such as short-chain fatty acids. Once sepsis is established, the alteration of the gastrointestinal microbiome worsens and the susceptibility to end-organ dysfunction increases. There is limited evidence that microbiome-based therapies, which include probiotics and selective digestive decontamination, can decrease the risk of sepsis and improve its outcomes in selected patient populations. However, safety concerns generate limited acceptance. While much of the evidence linking the gastrointestinal microbiome and sepsis has been established in preclinical studies, clinical evidence is still necessary in many areas.

The diversity and coexistence of extracellular mitochondria in circulation: A friend or foe of the immune system.

The diversity and coexistence of extracellular mitochondria may have a key role in the maintenance of health and progression of disease. Studies report that active mitochondria can be found physiologically outside of cells and circulating in the blood without inducing an inflammatory response. In addition, inactive or harmed mitochondria have been recognized as activators of immune cells, as they play an essential role in diseases characterized by the metabolic deregulation of these cells, such as sepsis. In this review we analyze key aspects regarding the existence of a diversity of extracellular mitochondria, their coexistence in body fluids and their effects on various immune cells. Additionally, we introduce models of how extracellular mitochondria could be interacting to maintain health and affect disease prognosis. Unwrapped mitochondria (freeMitos) can exist as viable, active, inactive or harmed organelles. Mitochondria can also be found wrapped in a membrane (wrappedMitos) that may differ depending on the cell of origin. Mitochondrial fragments can also be present in various body fluids as DAMPs, as mtDNA enclosed in vesicles or as circulating-cell-free mtDNA (ccf-mtDNA). Interestingly, the great quantity of evidence regarding the levels of ccf-mtDNA and their correlation with aging and disease allows for the identification of the diversity, but not type, of extracellular mitochondria. The existence of a diversity of mitochondria and their effects on immune cells opens a new concept in the biomedical field towards the understanding of health, the progression of disease and the development of mitochondria as therapeutic agents.

Aclaramiento del lactato: revisión de la literatura / Lactate clearance: review of the literature

Cuando hablamos del aclaramiento de lactato debemos conocer con claridad la complejidad del proceso, pues abarca todo el metabolismo del lactato desde su producción hasta su remoción: a este proceso se ha denominado equilibrio reversible de lactato. Este concepto que permitirá entender mejor los procesos dinámicos de su metabolismo no como producto final o de desecho (según, tradicionalmente, se nos ha hecho creer) sino, más bien, como un producto intermedio que ejerce funciones específicas y bien definidas que lo convierten no sólo en indicador de perfusión tisular sino en un indicador global del metabolismo celular.

When we talk about lactate clearance we have to be clear about the complexity of the process, since it involves the metabolism of lactate from its production to its removal what has been called reversible lactate equilibrium, this concept that will allow us to better understand the dynamic processes of its metabolism not as a final product or waste, as we have traditionally been led to believe, but rather as an intermediate product with specific and welldefined functions that make it not only an indicator of tissue perfusion, but a global indicator of metabolism cell

Safety concerns of Piezoelectric Units in Implantable Cardioverter Defibrillator.

PURPOSE: Evidence-based research appears to conflict on the potential risk of electromagnetic interference (EMI) between piezoelectric units (Pzs) and implantable cardioverters and defibrillators (ICDs). The purpose of this study was to observe whether the EMI produced by Pzs is hazardous for ICDs. MATERIALS AND METHODS: A cross-sectional study of 6 Pzs was conducted in vitro for EMI using an ICD system. To simulate the human body's electrical resistance, electrographic recordings were made of the ICD and lead that were immersed in a bath of saline solution. The variables investigated were the presence of EMI, the distance between the ICD and the Pz, and signal intensity, damage, and type of damage to the ICD and lead. Each series of tests was repeated 3 times, beginning with a 15-second baseline recording (control), until all recording conditions had been covered. Each Pz was recorded under the following conditions: less than 2 cm from the tip of the ICD lead; less than 2 cm from the ICD; less than 2 cm from the lead body and coils; and 15 cm from the lead or the ICD (R4). RESULTS: In the positive control (direct contact between the lead or the ICD with the Pz switched on), the ICD detected electrical activity as false heart activity. However, after covering all test conditions, no EMI was produced by the Pzs. CONCLUSION: No EMI or permanent changes in the functioning of the ICD were detected in vitro.

La saturación venosa central de oxígeno es un factor predictor de mortalidad en el paciente con choque séptico / Central venous oxygen saturation is a predictor of mortality in patients with septic shock

Objetivo: determinar si la saturación venosa central de oxigeno inicial (SvCO2) anormal (alta o baja) es un factor predictor de mortalidad en los pacientes con choque séptico que ingresan al área critica de emergencia del hospital "Carlos Andrade Marín". Diseño y lugar: estudio analítico, observacional, prospectivo sobre una cohorte de pacientes que ingresaron al área crítica de emergencia de este hospital. Pacientes: 107 sujetos ingresaron en los meses de junio a septiembre del 2015, con seguimiento para la mortalidad a 28 días. Medidas y resultados: se midió la SvcO2 inicial a través de un catéter venoso central al momento del diagnóstico de choque. La mortalidad a los 28 días fue de 46,2%. Solo los valores de APACHE II (OR:1,11; IC: 1,04 a 1,19 p=< 0,01); la asistencia ventilatoria mecánica (OR:0,19; IC: 0,05 a 0,62, p=<0,01) tuvieron un valor estadístico significativo en regresión logística. APACHE II fue el factor individual más importante, en el modelo CART, el pH arterial y procalcitonina fueron útiles. Conclusiones: la saturación venosa central de O2 inicial (SvcO2) anormal alta o baja no mostró tener utilidad para predecir mortalidad a los 28 días. La medición de la SvcO2 es un método simple que refleja de manera indirecta la oxigenación tisular. El APACHE II es un predictor independiente de mortalidad a 28 días y la ventilación mecánica tuvo una relación inversa con la mortalidad. (AU)

Objective: to determine the central venous saturation of abnormal initial oxygen (SvCO2) (high or low) as a predictor of mortality in patients with septic shock admitted to the emergency area of Carlos Andrade Marín Hospital. Design and location: this is an analytical, observational, prospective study on a cohort of patients admitted to the critical area of emergency of this health unit. Subjects: 107 patients admitted in the months of June to September 2015, with a mortality follow-up of 28-day. Measurements and results: initial SvcO2 was measured by central venous catheter at the time of shock diagnosis. Mortality at 28 days was 46.2%. Only APACHE II values (OR 1.11, CI 1.04-1.19 p = <0.01) and mechanical ventilation (OR 0.19, CI 0.05-0.62, p = 0.01) had significant statistical value in the logistic regression. APACHE II was the most important single factor, in the CART model arterial pH and procalcitonin were useful. Conclusion: Central venous saturation of abnormal or high initial O2 (SvcO2) was not found to be useful in predicting mortality at 28 days of follow-up. Measurement of SvcO2 is a simple method that indirectly reflects tissue oxygenation. The APACHE II is an independent predictor of mortality at 28 days and the use of mechanical ventilation had an inverse relationship with mortality. (AU)

Fisiología, bioquímica y metabolismo del ácido láctico: revisión de la literatura / Physiology, biochemistry and metabolism of lactic acid: review of the literature

El ácido láctico o lactato es un marcador bioquímico cuyo rol biológico ha ido adquiriendo mayor importancia a medida que entendemos su comportamiento bioquímico, fisiológico, metabólico y fisiopatológico. Inicialmente fue visto como un sustrato nocivo y luego, paulatinamente entendido como una vía vital de supervivencia celular y sustrato energético en condiciones extremas y aún normales (sistema nervioso central). Actualmente es un objetivo de resucitación hemodinámica, tan importante, que su descenso o ascenso luego de reanimación hemodinámica predice alta morbilidad y mortalidad. En esta revisión tenemos el propósito de facilitar el entendimiento del metabolismo del lactato y, por tanto, de la glucosa (ambas sustancias comparten paralelismos bioquímicos y metabólicos), recalcar la importancia del hígado y del músculo esquelético y alcanzar enfoques traslacionales sobre el tema.(AU)

Lactic acid or lactate is a biochemical marker whose biological role has become more important as we understand its biochemical, physiological, metabolic and pathophysiological behavior. Initially it was seen as a harmful substrate and then, gradually understood as a vital way of cell survival and energy substrate in extreme and still normal conditions (central nervous system). Currently, it is an important hemodynamic resuscitation objective, that its descent or rise after hemodynamic resuscitation predicts high morbidity and mortality. In this review we will try to facilitate the understanding of lactate metabolism and, therefore, of glucose (both substances share biochemical and metabolic parallelisms), emphasize the importance of the liver and skeletal muscle and achieve translational approaches on the subject.(AU)

Effects of piezoelectric units on pacemaker function: an in vitro study.

INTRODUCTION: The use of piezoelectric units on patients with pacemakers is generally discouraged, although there is no empirical evidence of the effects of current piezoelectric units on pacemaker activity in vitro. METHODS: Four piezoelectric units (Piezosurgery3, Piezotome, Piezotome2, and Variosurg) and 2 magnetostriction units (Piezotome and Piezotome2) were tested for electromagnetic interference (EMI) with the SENSIA SESR01 pacemaker from Medtronic. The pacemaker, with a single electrode, was immersed in a saline-solution bath and adjusted between 400 and 800 ohms to simulate the electrical resistance of the human body and to register and to produce electrographic recordings. The pacemaker was tested with each ultrasonic device to analyze the presence of EMI at different distances, with the ultrasound switched on, switched off, and during operation. If any of the devices produced interference, the characteristics of the interference were categorized. RESULTS: In the positive control (direct contact between either the electrode or the generator and the ultrasound device when this was switched on), the pacemaker detected electrical activity as false heart activity. When all the scenarios and distances had been covered, no EMI was produced by the ultrasound units. CONCLUSIONS: No EMI was detected during the testing of the piezoelectric or magnetostriction units in this in vitro model of pacemaker use.

Victims of bullying in the emergency department with behavioral issues.

BACKGROUND: Bullying has become one of the most significant school problems experienced by our children. Victims of bullying are prone to a variety of psychological and behavioral symptoms. We noted that many children referred to the Emergency Department (ED) with behavioral symptoms provided a history of bullying. OBJECTIVES: To measure the prevalence of bullying in children referred to the ED for behavioral symptoms and to determine its association with psychiatric disorders. METHODS: A retrospective cohort study was conducted in an urban hospital, identifying children from 8 to 19 years of age who presented to the ED with behavioral symptoms. We reviewed the ED psychiatry notes to retrieve the report indicating whether these children were bullied and had previous psychiatric diagnoses. These children were classified into bullied and non-bullied groups. RESULTS: Over the study period, 591 children visited the ED with behavioral issues. Out of 591, 143 (24%) children reported bullying. More boys (100) than girls (43) reported bullying (p = 0.034). The mean age of children in the bullied group was 10.6 years (95% confidence interval 10.1-11.2). One hundred eleven (77.6%) children in the bullied group had a prior psychiatric diagnosis. Children in the bullied group were hospitalized significantly less than children in the non-bullied group (10/143 [7%] vs. 80/368 [18%]; p = 0.002). CONCLUSION: The prevalence of bullying among the ED children with behavioral symptoms is substantial. Every fourth child with behavioral symptoms reported bullying. Four in five children who reported bullying had a prior diagnosis of "disorder of behavior."

Lipemic serum in a toddler with new-onset diabetes mellitus presenting with diabetic ketoacidosis.

CONTEXT: Significant hyperlipidemia causing lipemic serum in patients with poorly controlled diabetes is under-reported in children. The recognition of the severe hyperlipidemia is important for proper management and to prevent associated morbidities. Severe hyperlipidemia in patients with diabetic ketoacidosis should be considered. CASE REPORT: In this case we report a 2-year-old girl with new onset type 1 diabetes mellitus, who presented with severe diabetic ketoacidosis and hyperlipidemia. Hyperlipidemia was resolved with hydration and insulin therapy. CONCLUSION: It is important to diagnose hyperlipidemia by checking serum lipid profile for all pediatric patients presenting with hyperglycemic crisis to prevent morbidities.

Spontaneous resolution of a large traumatic pneumothorax.

The aim of this study was to describe a case of a large traumatic pneumothorax (>55%) that resolved completely without intervention. A pneumothorax is the accumulation of air between the visceral and parietal pleura. It can occur spontaneously or be traumatic. Spontaneous pneumothoraces can occur with no underlying lung disease or secondary in nature. The emergency department (ED) treatment of pneumothoraces depends on their size, their etiology, and clinical stability of the patient. The current recommendation is observation in stable patients with <15% pneumothorax and tube thoracostomy in patients with >15% pneumothorax. A 33-year-old woman presented to our ED complaining of right knee and right lateral chest wall pain after falling. Her breath sounds were reported as normal. A chest radiograph was ordered, which showed a large right-sided pneumothorax with tracheal deviation suggestive of a tension pneumothorax. The provider did not appreciate the pneumothorax at the time, and she was subsequently discharged home. The radiograph was over-read in the morning, and several attempts were made to recall the patient but were unsuccessful. Fortunately, the patient returned to the ED for an unrelated complaint approximately 1 month later, and the radiograph was repeated, confirming full resolution of the pneumothorax. She was not treated at another facility during that time. This is a typical manifestation of a traumatic pneumothorax but with an atypical course and outcome. It raises the question of whether, even in the case of traumatic pneumothorax, the threshold for placement of chest tubes could be reconsidered in stable patients.

An adolescent with lower-extremity swelling.

Lower-extremity swelling is an uncommon presentation in a pediatric emergency department. Deep venous thrombosis is one of the common differential diagnoses in a patient with an underlying predisposing factor. We report a case of a previously healthy adolescent without any risk factor for thromboembolism presented with deep venous thrombosis. The pertinent literature is reviewed.

Neuropsychiatric manifestations in late-onset urea cycle disorder patients.

Inherited urea cycle disorders represent one of the most common groups of inborn errors of metabolism. Late-onset urea cycle disorders caused by partial enzyme deficiencies may present with unexpected clinical phenotypes. We report 9 patients followed up in our hospital presenting late-onset urea cycle disorders who initially manifested neuropsychiatric/neurodevelopmental symptoms (the most prevalent neuropsychiatric/neurodevelopmental diagnoses were mental retardation, attention-deficit hyperactivity disorder [ADHD], language disorder, and delirium). Generally, these clinical pictures did not benefit from pharmacological treatment. Conversely, dietary treatment improved the symptoms. Regarding biochemical data, 2 patients showed normal ammonium but high glutamine levels. This study highlights the fact that neuropsychiatric/neurodevelopmental findings are common among the initial symptomatology of late-onset urea cycle disorders. The authors recommend that unexplained or nonresponsive neuropsychiatric/neurodevelopmental symptoms appearing during childhood or adolescence be followed by a study of ammonia and amino acid plasmatic levels to rule out a urea cycle disorder.

Maximum FIO2 in minimum time depending on the kind of resuscitation bag and oxygen flow.

OBJECTIVE: To analyze what FIO2 can be reached, and how long it takes using the different autoinflated resuscitation bags and increasing oxygen flows. DESIGN: Experimental analysis on the effect of three different models of autoinflated resuscitation bag and increasing oxygen flows in the final FIO2, and time spent to reach it. SETTING: Laboratory, with a gas analyzer and a lung simulator to measure inspired FIO2. INTERVENTIONS: Simulated cardiopulmonary resuscitation. Three different autoinflated resuscitation bags were studied; A, the classic one with oxygen delivery directly into the bag, without reservoir, B, a new one without the reservoir device; and C, a new one with the reservoir device properly implemented. Increasing oxygen flows were administered until FIO2 stabilized. RESULTS: With model A the maximum FIO2 reached was 0.73 in 70 s using a 20 l/min oxygen flow. With model B the maximum FIO2 reached was 0.65 in 90 s using a 20 l/min oxygen flow. The best FIO2 (0.99) was reached using model C in 55 s with 12 l/min oxygen flow. In the three models a high correlation between oxygen flow and FIO2 was found (r>0.8). CONCLUSIONS: It is mandatory to use model C resuscitation autoinflated bag with 12 l/min of oxygen flow during the resuscitation maneuvers. Using another autoinflated bag model, maximum oxygen flows (i.e., 20 l/min) are needed. The resuscitation autoinflated bags showed less effectiveness when they were not properly assembled.

[A competitive fund of development to improve the quality of university education in Chile. Area of health care]. / Un fondo competitivo de desarrollo para el fomento de la calidad de la educación superior en Chile. Area de la salud.

In 1997, the Chilean Government and the International Bank for Development convened on a strategy to improve Chilean university education. It was based on quality improvement, effectiveness, relevancy and innovation on university education programs. A US$ 245 millions fund was afforded, for a five years competitive grants program, among certain traditional Universities and Technical Education Institutes. The authors reviewed the projects that won the contests during the first three years in the health area, to determine their impact, demands supported, difficulties and assets. These projects obtained 13.6% of the assigned funds (a total of US$ 16.5 millions). Funds were requested mostly to build spaces, obtain equipment, laboratories and computational support. Funds were also requested to carry out methodological changes and teaching improvements. The importance of teaching health sciences in locations outside the Metropolitan area of Santiago, the modification of undergraduate medical curriculum and the development of post graduate networks are emphasized.

Electron beam coronary angiography to assess patency in the off-pump coronary bypass graft.

BACKGROUND: Off-pump coronary artery bypass is widely practiced today, with critics questioning patency rates. This study was conducted to determine the feasibility of using electron beam coronary angiography to determine patency in this group of patients. METHODS: A total of 27 patients from a series of 653 off-pump coronary artery bypass patients were selected at random and, after informed consent, underwent electron beam coronary angiography with an Imatron C150 single slide mode using loversol as contrast material injected in an antecubital vein. RESULTS: A total of 88 bypasses were studied with an average of 3.2 +/- 0.7125 grafts per patient, with a mean follow-up of 20.3 months. Four bypasses were occluded. CONCLUSIONS: Electron beam coronary angiography appears to be a safe, suitable test to demonstrate patency in the off-pump coronary artery bypass graft patient, allowing study of a large group of patients without the risk or discomfort of cardiac catheterization.