Therapeutic variability in infants admitted to Latin-American pediatric intensive units due to acute bronchiolitis. / Variabilidad terapéutica en lactantes con bronquiolitis hospitalizados en unidades de cuidados intensivos latinoamericanas.

The objective of this study was to describe the management of infants with acute bronchiolitis admit ted to 20 pediatric intensive care units (PICU) members of LARed in 5 Latin American countries. Pa tients and Method: Retrospective, multicenter, observational study of data from the Latin American Registry of Acute Pediatric Respiratory Failure. We included children under 2 years of age admitted to the PICU due to community-based acute bronchiolitis between May and September 2017. Demo graphic and clinical data, respiratory support, therapies used, and clinical results were collected. A subgroup analysis was carried out according to geographical location (Atlantic v/s Pacific), type of insurance (Public v/s Private), and Academic v/s non-Academic centers. Results: 1,155 patients were included in the registry which present acute respiratory failure and 6 were excluded due to the lack of information in their record form. Out of the 1,147 patients, 908 were under 2 years of age, and out of those, 467 (51.4%) were diagnosed with acute bronchiolitis, which was the main cause of admission to the PICU due to acute respiratory failure. The demographic and severity characteristics among the centers were similar. The most frequent maximum ventilatory support was the high-flow nasal can nula (47%), followed by non-invasive ventilation (26%) and invasive mechanical ventilation (17%), with a wide coefficient of variation (CV) between centers. There was a great dispersion in the use of treatments, where the use of bronchodilators, antibiotics, and corticosteroids, representing a CV up to 400%. There were significant differences in subgroup analysis regarding respiratory support and treatments used. One patient of this cohort passed away. Conclusion: we detected wide variability in respiratory support and treatments among Latin American PICUs. This variability was not explained by demographic or clinical differences. The heterogeneity of treatments should encourage collabora tive initiatives to reduce the gap between scientific evidence and practice.

Extreme Neonatal Hypernatremia and Acute Kidney Injury Associated with Failure of Lactation.

Hypoalimentation is an important cause of hypernatremic dehydration in neonates; however, extreme values of plasma sodium make it necessary to investigate the differential diagnosis. We report the case of a 20-day-old newborn who was admitted with severe hypernatremic dehydration, with plasma sodium of 213 mEq/L and oliguric acute renal failure. The patient was treated with intravenous fluids for correction of dehydration and peritoneal dialysis for adequate sodium correction. During the etiological study, a 10-fold increase in the concentration of sodium in breast milk was detected. Peritoneal dialysis was an effective therapy in the management of the extreme hypernatremia with sodium correction within the recommended rate. At the 1-year follow-up appointment, the child had normal renal function, normal for age psychomotor development, and neurological physical was unremarkable. In conclusion, we report a case of an unusual extreme hypernatremia with discussion of the underlying pathophysiology and, more importantly, the effective treatment with a mixed approach with intravenous fluids and peritoneal dialysis.

Variabilidad terapéutica en lactantes con bronquiolitis hospitalizados en unidades de cuidados intensivos latinoamericanas / Therapeutic variability in infants admitted to Latin-American pediatric intensive units due to acute bronchiolitis

Resumen: Objetivo: describir las terapias utilizadas en lactantes con bronquiolitis aguda admitidos en 20 Uni dades de Cuidados Intensivos (UCI) pediátricos miembros de LARed en 5 países latinoamerica nos. Pacientes y Método: Estudio observacional retrospectivo, multicéntrico, de datos del Registro Latinoamericano de Falla Respiratoria Aguda Pediátrica. Se incluyeron niños menores de 2 años ingresados a UCI pediátrica por bronquiolitis aguda comunitaria entre mayo-septiembre 2017. Se recolectaron datos demográficos, clínicos, soporte respiratorio, terapias utilizadas y resultados clí nicos. Se realizó análisis de subgrupos según ubicación geográfica, tipo financiación y presencia de academia. Resultados: Ingresaron al registro 1155 pacientes con falla respiratoria aguda. Seis casos fueron excluidos por no tener formulario completo. De los 1147 pacientes, 908 eran menores de 2 años. De ellos, 467 tuvieron diagnóstico de bronquiolitis aguda, correspondiendo a la principal causa de ingreso a UCI pediátrica por falla respiratoria aguda (51,4%). Las características demográficas y de gravedad entre los centros fueron similares. El soporte máximo respiratorio más frecuente fue cánula nasal de alto flujo (47%), seguido por ventilación mecánica no invasiva (26%) y ventilación mecánica invasiva (17%), con un coeficiente de variación (CV) amplio entre los centros. Hubo una gran dispersión en uso de terapias, siendo frecuente el uso de broncodilatadores, antibióticos y corticoides, con CV hasta 400%. El análisis de subgrupos mostró diferencias significativas en soporte respiratorio y tratamientos utilizados. Un paciente falleció en esta cohorte. Conclusión: Detectamos gran variabilidad en el soporte respiratorio y tratamientos entre UCI pediátricas latinoamericanas. Esta variabilidad no es explicada por disparidades demográficas ni clínicas. Esta heterogeneidad de tratamientos debería promover iniciativas colaborativas para disminuir la brecha entre la evidencia científica y la práctica asistencial.

Abstract: The objective of this study was to describe the management of infants with acute bronchiolitis admit ted to 20 pediatric intensive care units (PICU) members of LARed in 5 Latin American countries. Pa tients and Method: Retrospective, multicenter, observational study of data from the Latin American Registry of Acute Pediatric Respiratory Failure. We included children under 2 years of age admitted to the PICU due to community-based acute bronchiolitis between May and September 2017. Demo graphic and clinical data, respiratory support, therapies used, and clinical results were collected. A subgroup analysis was carried out according to geographical location (Atlantic v/s Pacific), type of insurance (Public v/s Private), and Academic v/s non-Academic centers. Results: 1,155 patients were included in the registry which present acute respiratory failure and 6 were excluded due to the lack of information in their record form. Out of the 1,147 patients, 908 were under 2 years of age, and out of those, 467 (51.4%) were diagnosed with acute bronchiolitis, which was the main cause of admission to the PICU due to acute respiratory failure. The demographic and severity characteristics among the centers were similar. The most frequent maximum ventilatory support was the high-flow nasal can nula (47%), followed by non-invasive ventilation (26%) and invasive mechanical ventilation (17%), with a wide coefficient of variation (CV) between centers. There was a great dispersion in the use of treatments, where the use of bronchodilators, antibiotics, and corticosteroids, representing a CV up to 400%. There were significant differences in subgroup analysis regarding respiratory support and treatments used. One patient of this cohort passed away. Conclusion: we detected wide variability in respiratory support and treatments among Latin American PICUs. This variability was not explained by demographic or clinical differences. The heterogeneity of treatments should encourage collabora tive initiatives to reduce the gap between scientific evidence and practice.

Peritonitis tuberculosa en un niño / Pediatric tuberculous peritonitis: case report

Resumen La peritonitis tuberculosa es una entidad infrecuente en la población pediátrica. Es una forma poco común de tuberculosis extrapulmonar y representa un muy bajo porcentaje de todos los casos de tuberculosis. Sus síntomas son inespecíficos, manifestándose usualmente con ascitis, dolor abdominal, fiebre y baja de peso. El retraso en su diagnóstico y tratamiento, dada su forma de presentación, puede incrementar su morbimortalidad. Se comunica el caso de una adolescente de 14 años, previamente sana, quien se presentó con fiebre y ascitis. La laparoscopia demostró múltiples nódulos en la cavidad abdominal compatibles con una tuberculosis peritoneal, la cual fue posteriormente confirmada por cultivo y biología molecular. La paciente completó su tratamiento antituberculoso recuperándose en forma satisfactoria.

Tuberculous peritonitis is an uncommon entity in the infant population. It is an uncommon form of extrapulmonary tuberculosis and represents a very low percentage of all cases of tuberculosis. Its symptoms are nonspecific and usually manifesting with ascites, abdominal pain, fever and low weight. The delay in its diagnosis and treatment, originated by its form of presentation, can cause an increase in its morbidity and mortality. We report the case of a 14-year-old patient without concomitant disease or pulmonary tuberculosis, who presented with ascites and fever. Laparoscopy showed multiple nodules in the abdominal cavity compatible with peritoneal tuberculosis, which was subsequently confirmed by culture and molecular test. The patient completed her antituberculosis treatment recovering satisfactorily.

[Pediatric tuberculous peritonitis. Case report]. / Peritonitis tuberculosa en un niño.

Tuberculous peritonitis is an uncommon entity in the infant population. It is an uncommon form of extrapulmonary tuberculosis and represents a very low percentage of all cases of tuberculosis. Its symptoms are nonspecific and usually manifesting with ascites, abdominal pain, fever and low weight. The delay in its diagnosis and treatment, originated by its form of presentation, can cause an increase in its morbidity and mortality. We report the case of a 14-year-old patient without concomitant disease or pulmonary tuberculosis, who presented with ascites and fever. Laparoscopy showed multiple nodules in the abdominal cavity compatible with peritoneal tuberculosis, which was subsequently confirmed by culture and molecular test. The patient completed her antituberculosis treatment recovering satisfactorily.

[Fiebre y terapia antipirética en el paciente con sepsis en la unidad de cuidados intensivos: actualización]. / Fever and antipyretic therapy in the septic patient in the intensive care unit: an update.

La fiebre es un signo frecuente en el niño críticamente enfermo durante su estadía en la unidad de cuidados intensivos, y debe ser entendida como una respuesta biológica evolutiva, de carácter adaptativo normal del huésped al estrés fisiológico. Es el resultado de una compleja respuesta a estímulos pirogénicos, resultando en la generación de citocinas y prostaglandinas. Los mecanismos moleculares implicados en el inicio de la fiebre aún no están totalmente precisados, originando dificultades en el conocimiento de los procesos fisiopatológicos exactos involucrados y, por ende, necesarios para elaborar una adecuada y específica estrategia terapéutica. Estudios experimentales concluyen que la fiebre y la inflamación son benéficas para el huésped; no obstante, la terapia antipirética es comúnmente empleada y estudios en humanos sobre la presencia de fiebre y su tratamiento para el pronóstico del paciente crítico con sepsis no son concluyentes. Para el médico intensivista es esencial disponer de información actualizada referente a la fisiología de la termorregulación humana, el efecto de la temperatura en rango febril sobre múltiples procesos biológicos involucrados en la defensa del huésped y las intervenciones termorreguladoras en el paciente con sepsis.Fever is a very common sign to observe in critically ill children during their intensive care unit stay. This should be understood as an evolutionary biological response, of normal adaptive character, from the host to the physiological stress. It is the result of a complex response to pyrogenic stimuli, resulting in the generation of cytokines and prostaglandins. The molecular mechanisms involved in the onset of fever are not yet fully specified, thus creating difficulties in the knowledge of the exact pathophysiological processes involved and, therefore, necessary to elaborate an adequate and specific therapeutic strategy. Experimental studies conclude that fever and inflammation are beneficial to the host. However, antipyretic therapy is commonly employed and human studies on the presence of fever and its treatment for the prognosis of critically ill septic patients are inconclusive. Up-to-date information on the physiology of human thermoregulation, the effect of temperature on febrile range over multiple biological processes involved in host defense, and thermoregulatory interventions in the septic patient are essential to know by the critical care physician.

Fiebre y terapia antipirética en el paciente con sepsis en la unidad de cuidados intensivos: actualización / Fever and antipyretic therapy in the septic patient in the intensive care unit: an update

Resumen La fiebre es un signo frecuente en el niño críticamente enfermo durante su estadía en la unidad de cuidados intensivos, y debe ser entendida como una respuesta biológica evolutiva, de carácter adaptativo normal del huésped al estrés fisiológico. Es el resultado de una compleja respuesta a estímulos pirogénicos, resultando en la generación de citocinas y prostaglandinas. Los mecanismos moleculares implicados en el inicio de la fiebre aún no están totalmente precisados, originando dificultades en el conocimiento de los procesos fisiopatológicos exactos involucrados y, por ende, necesarios para elaborar una adecuada y específica estrategia terapéutica. Estudios experimentales concluyen que la fiebre y la inflamación son benéficas para el huésped; no obstante, la terapia antipirética es comúnmente empleada y estudios en humanos sobre la presencia de fiebre y su tratamiento para el pronóstico del paciente crítico con sepsis no son concluyentes. Para el médico intensivista es esencial disponer de información actualizada referente a la fisiología de la termorregulación humana, el efecto de la temperatura en rango febril sobre múltiples procesos biológicos involucrados en la defensa del huésped y las intervenciones termorreguladoras en el paciente con sepsis.

Abstract Fever is a very common sign to observe in critically ill children during their intensive care unit stay. This should be understood as an evolutionary biological response, of normal adaptive character, from the host to the physiological stress. It is the result of a complex response to pyrogenic stimuli, resulting in the generation of cytokines and prostaglandins. The molecular mechanisms involved in the onset of fever are not yet fully specified, thus creating difficulties in the knowledge of the exact pathophysiological processes involved and, therefore, necessary to elaborate an adequate and specific therapeutic strategy. Experimental studies conclude that fever and inflammation are beneficial to the host. However, antipyretic therapy is commonly employed and human studies on the presence of fever and its treatment for the prognosis of critically ill septic patients are inconclusive. Up-to-date information on the physiology of human thermoregulation, the effect of temperature on febrile range over multiple biological processes involved in host defense, and thermoregulatory interventions in the septic patient are essential to know by the critical care physician.

Monitorización respiratoria del paciente pediátrico en la Unidad de Cuidados Intensivos / Respiratory monitoring of pediatric patients in the Intensive Care Unit

Resumen: La monitorización respiratoria representa un importante rol en el cuidado del niño con falla respiratoria aguda. Por tanto, su apropiado uso y correcta interpretación (reconociendo qué señales y variables deben ser priorizadas) deberían ayudar a un mejor entendimiento de la fisiopatología de la enfermedad y de los efectos de las intervenciones terapéuticas. Asimismo, la monitorización del paciente ventilado permite, entre otras determinaciones, evaluar diversos parámetros de la mecánica respiratoria, conocer el estado de los diferentes componentes del sistema respiratorio y guiar los ajustes de la terapia ventilatoria. En esta actualización se describe la utilidad de diversas técnicas de monitorización respiratoria (incluyendo métodos convencionales y otros más recientes), se definen conceptos básicos de mecánica ventilatoria, su interpretación y cómo el adecuado análisis de la información puede ocasionar un impacto en el manejo clínico del paciente.

Abstract: Respiratory monitoring plays an important role in the care of children with acute respiratory failure. Therefore, its proper use and correct interpretation (recognizing which signals and variables should be prioritized) should help to a better understanding of the pathophysiology of the disease and the effects of therapeutic interventions. In addition, ventilated patient monitoring, among other determinations, allows to evaluate various parameters of respiratory mechanics, know the status of the different components of the respiratory system and guide the adjustments of ventilatory therapy. In this update, the usefulness of several techniques of respiratory monitoring including conventional respiratory monitoring and more recent methods are described. Moreover, basic concepts of mechanical ventilation, their interpretation and how the appropriate analysis of the information obtained can cause an impact on the clinical management of the patient are defined.

[Respiratory monitoring of pediatric patients in the Intensive Care Unit]. / Monitorización respiratoria del paciente pediátrico en la Unidad de Cuidados Intensivos.

Respiratory monitoring plays an important role in the care of children with acute respiratory failure. Therefore, its proper use and correct interpretation (recognizing which signals and variables should be prioritized) should help to a better understanding of the pathophysiology of the disease and the effects of therapeutic interventions. In addition, ventilated patient monitoring, among other determinations, allows to evaluate various parameters of respiratory mechanics, know the status of the different components of the respiratory system and guide the adjustments of ventilatory therapy. In this update, the usefulness of several techniques of respiratory monitoring including conventional respiratory monitoring and more recent methods are described. Moreover, basic concepts of mechanical ventilation, their interpretation and how the appropriate analysis of the information obtained can cause an impact on the clinical management of the patient are defined.

Decreased lung compliance increases preload dynamic tests in a pediatric acute lung injury model / Una compliance pulmonar disminuida incrementa los test dinámicos de precarga en un modelo pediátrico de lesión pulmonar aguda

Background: Preload dynamic tests, pulse pressure variation (PPV) and stroke volume variation (SVV) have emerged as powerful tools to predict response to fluid administration. The influence of factors other than preload in dynamic preload test is currently poorly understood in pediatrics. The aim of our study was to assess the effect of tidal volume (V T) on PPV and SVV in the context of normal and reduced lung compliance in a piglet model. Material and method: Twenty large-white piglets (5.2 ± 0.4 kg) were anesthetized, paralyzed and monitored with pulse contour analysis. PPV and SVV were recorded during mechanical ventilation with a V T of 6 and 12 mL/kg (low and high V T, respectively), both before and after tracheal instillation of polysorbate 20. Results: Before acute lung injury (ALI) induction, modifications of V T did not significantly change PPV and SVV readings. After ALI, PPV and SVV were significantly greater during ventilation with a high V T compared to a low V T (PPV increased from 8.9 ± 1.2 to 12.4 ± 1.1%, and SVV from 8.5 ± 1.0 to 12.7 ± 1.2%, both P < 0.01). Conclusions: This study found that a high V T and reduced lung compliance due to ALI increase preload dynamic tests, with a greater influence of the latter. In subjects with ALI, lung compliance should be considered when interpreting the preload dynamic tests.

Introducción: Test dinámicos de precarga, variación de presión de pulso (PPV) y variación de volumen sistólico (SVV) han emergido como herramientas poderosas para predecir respuesta a la administración de fluidos. Actualmente la influencia de factores distintos a la precarga en la determinación de los test dinámicos de precarga es pobremente conocida en pediatría. Nuestro objetivo fue medir el efecto del volumen tidal (V T) sobre PPV y SVV en un contexto de compliance pulmonar normal y disminuida en un modelo porcino. Material y método: Veinte cerditos Large-White anestesiados y paralizados (5,2 ± 0,4 kg). PPV y SVV fueron medidos por análisis de contorno de pulso durante ventilación con V T de 6 y 12 mL/kg (V T bajo y alto, respectivamente), ambos previo y posterior a lesión pulmonar aguda (ALI) químicamente inducida con instilación traqueal de polisorbato 20. Resultados: Previo a inducción de ALI, PPV y SVV no tuvieron cambios significativos al modificar el V T. Sin embargo, después de ALI, PPV y SVV fueron significativamente mayores durante ventilación con V T alto, respecto a V T bajo (PPV aumentó de 8,9 ± 1,2 a 12,4 ± 1,1%, y SVV de 8,5 ± 1,0 a 12,7 ± 1,2%, ambos P < 0,01). Conclusiones: Este estudio encontró que un V T alto y una compliance pulmonar disminuida debido a ALI incrementan los test dinámicos de precarga, con una mayor influencia de esta última. En sujetos con ALI la compliance pulmonar debiera ser considerada al interpretar los test dinámicos de precarga.

Decreased lung compliance increases preload dynamic tests in a pediatric acute lung injury model.

BACKGROUND: Preload dynamic tests, pulse pressure variation (PPV) and stroke volume variation (SVV) have emerged as powerful tools to predict response to fluid administration. The influence of factors other than preload in dynamic preload test is currently poorly understood in pediatrics. The aim of our study was to assess the effect of tidal volume (VT) on PPV and SVV in the context of normal and reduced lung compliance in a piglet model. MATERIAL AND METHOD: Twenty large-white piglets (5.2±0.4kg) were anesthetized, paralyzed and monitored with pulse contour analysis. PPV and SVV were recorded during mechanical ventilation with a VT of 6 and 12mL/kg (low and high VT, respectively), both before and after tracheal instillation of polysorbate 20. RESULTS: Before acute lung injury (ALI) induction, modifications of VT did not significantly change PPV and SVV readings. After ALI, PPV and SVV were significantly greater during ventilation with a high VT compared to a low VT (PPV increased from 8.9±1.2 to 12.4±1.1%, and SVV from 8.5±1.0 to 12.7±1.2%, both P<0.01). CONCLUSIONS: This study found that a high VT and reduced lung compliance due to ALI increase preload dynamic tests, with a greater influence of the latter. In subjects with ALI, lung compliance should be considered when interpreting the preload dynamic tests.

[Invasive mechanical ventilation: Update for the pediatrician]. / Ventilación mecánica invasiva: Puesta al día para el médico pediatra.

In this review, we collect the fundamental concepts of the use of invasive mechanical ventilation (MV) in children, particularly in acute respiratory failure. MV is a common practice in the ICU and must be understood as a therapeutic intervention to replace the work of breathing while restores the balance between ventilatory demand and the patient's ability to sustain it. It is essential for the clinician to recognize that the goal of mechanical ventilatory support is not to normalize the patient's blood gases but providing a reasonable gas exchange; the benefts are obtained if the safety thresholds are not exceeded. Thus, this strategy has become the only tool available to limit the development of ventilator-induced lung injury (VILI).

[Multiorgan failure associated with hyperthermia in an infant with Prader-Willi syndrome. case report]. / Falla multiorgánica asociada a hipertermia en una lactante con síndrome de Prader-Willi. caso clínico.

Heat stroke is a medical emergency characterized primarily by an elevated core temperature associated with a systemic inflammatory response, which causes multiple organ dysfunction in which encephalopathy predominates. If it is not early treated has high mortality. The Prader-Willi syndrome is a multisystem genetic disorder secondary to an abnormality in long arm chromosome 15 (15q11-q13), characterized by neonatal central hypotonia, developmental delay, hypogonadism, hyperphagia and obesity. These patients are susceptible to developing thermoregulatory problems. We report the case of a 5-month-old infant, in whom a diagnosis of Prader-Willi syndrome was established in the course of a febrile episode without known focus, who developed multiorganic failure and rhabdomyolysis secondary to hyperthermia.

Ventilación mecánica invasiva: Puesta al día para el médico pediatra / Invasive mechanical ventilation: Update for the pediatrician

En esta revisión se recogen los conceptos fundamentales del uso de la ventilación mecánica (VM) invasiva, principalmente en la insufciencia respiratoria aguda. La VM es una práctica común en la unidad de cuidados intensivos (UCI) y debe ser entendida como una terapia de sostén destinada a sustituir el trabajo respiratorio mientras se restablece el balance entre la demanda ventilatoria y la capacidad del paciente para sostenerla. Se debe reconocer que el objetivo de la VM no es la normalización de los gases sanguíneos, sino obtener un intercambio gaseoso razonable, sin sobrepasar los umbrales de seguridad, lo que permite limitar el daño inducido por su uso.(AU)

In this review, we collect the fundamental concepts of the use of invasive mechanical ventilation (MV) in children, particularly in acute respiratory failure. MV is a common practice in the ICU and must be understood as a therapeutic intervention to replace the work of breathing while restores the balance between ventilatory demand and the patients ability to sustain it. It is essential for the clinician to recognize that the goal of mechanical ventilatory support is not to normalize the patients blood gases but providing a reasonable gas exchange; the benefts are obtained if the safety thresholds are not exceeded. Thus, this strategy has become the only tool available to limit the development of ventilator-induced lung injury (VILI).(AU)

Falla multiorgánica asociada a hipertermia en una lactante con síndrome de Prader-Willi. caso clínico / Multiorgan failure associated with hyperthermia in an infant with Prader-Willi syndrome. Case report

El golpe de calor es una emergencia médica y se debe entender como una forma de hipertermia asociada a una respuesta inflamatoria sistémica, que ocasiona falla multiorgánica y en la cual la disfunción del sistema nervioso central es predominante. Si no es tratada precozmente, puede ocasionar una alta mortalidad. El síndrome de Prader-Willi es un trastorno genético multisistémico secundario a una anormalidad en el brazo largo del cromosoma 15 (15q11-q13), caracterizado por hipotonía central neonatal, retraso del desarrollo psicomotor, hipogonadismo, hiperfagia y obesidad. Estos pacientes son proclives a presentar problemas de termorregulación. Se comunica el caso de una lactante de 5 meses en quien se estableció el diagnóstico de síndrome de Prader-Willi en el curso de un episodio febril sin foco conocido, que evolucionó con falla multiorgánica y rabdomiólisis secundaria a la hipertermia.(AU)

Heat stroke is a medical emergency characterized primarily by an elevated core temperature associated with a systemic inflammatory response, which causes multiple organ dysfunction in which encephalopathy predominates. If it is not early treated has high mortality. The Prader-Willi syndrome is a multisystem genetic disorder secondary to an abnormality in long arm chromosome 15 (15q11-q13), characterized by neonatal central hypotonia, developmental delay, hypogonadism, hyperphagia and obesity. These patients are susceptible to developing thermoregulatory problems. We report the case of a 5-month-old infant, in whom a diagnosis of Prader-Willi syndrome was established in the course of a febrile episode without known focus, who developed multiorganic failure and rhabdomyolysis secondary to hyperthermia.(AU)

Ventilación mecánica invasiva: Puesta al día para el médico pediatra / Invasive mechanical ventilation: Update for the pediatrician

En esta revisión se recogen los conceptos fundamentales del uso de la ventilación mecánica (VM) invasiva, principalmente en la insufciencia respiratoria aguda. La VM es una práctica común en la unidad de cuidados intensivos (UCI) y debe ser entendida como una terapia de sostén destinada a sustituir el trabajo respiratorio mientras se restablece el balance entre la demanda ventilatoria y la capacidad del paciente para sostenerla. Se debe reconocer que el objetivo de la VM no es la normalización de los gases sanguíneos, sino obtener un intercambio gaseoso razonable, sin sobrepasar los umbrales de seguridad, lo que permite limitar el daño inducido por su uso.

In this review, we collect the fundamental concepts of the use of invasive mechanical ventilation (MV) in children, particularly in acute respiratory failure. MV is a common practice in the ICU and must be understood as a therapeutic intervention to replace the work of breathing while restores the balance between ventilatory demand and the patient's ability to sustain it. It is essential for the clinician to recognize that the goal of mechanical ventilatory support is not to normalize the patient's blood gases but providing a reasonable gas exchange; the benefts are obtained if the safety thresholds are not exceeded. Thus, this strategy has become the only tool available to limit the development of ventilator-induced lung injury (VILI).

Falla multiorgánica asociada a hipertermia en una lactante con síndrome de Prader-Willi. caso clínico / Multiorgan failure associated with hyperthermia in an infant with Prader-Willi syndrome. Case report

El golpe de calor es una emergencia médica y se debe entender como una forma de hipertermia asociada a una respuesta inflamatoria sistémica, que ocasiona falla multiorgánica y en la cual la disfunción del sistema nervioso central es predominante. Si no es tratada precozmente, puede ocasionar una alta mortalidad. El síndrome de Prader-Willi es un trastorno genético multisistémico secundario a una anormalidad en el brazo largo del cromosoma 15 (15q11-q13), caracterizado por hipotonía central neonatal, retraso del desarrollo psicomotor, hipogonadismo, hiperfagia y obesidad. Estos pacientes son proclives a presentar problemas de termorregulación. Se comunica el caso de una lactante de 5 meses en quien se estableció el diagnóstico de síndrome de Prader-Willi en el curso de un episodio febril sin foco conocido, que evolucionó con falla multiorgánica y rabdomiólisis secundaria a la hipertermia.

Heat stroke is a medical emergency characterized primarily by an elevated core temperature associated with a systemic inflammatory response, which causes multiple organ dysfunction in which encephalopathy predominates. If it is not early treated has high mortality. The Prader-Willi syndrome is a multisystem genetic disorder secondary to an abnormality in long arm chromosome 15 (15q11-q13), characterized by neonatal central hypotonia, developmental delay, hypogonadism, hyperphagia and obesity. These patients are susceptible to developing thermoregulatory problems. We report the case of a 5-month-old infant, in whom a diagnosis of Prader-Willi syndrome was established in the course of a febrile episode without known focus, who developed multiorganic failure and rhabdomyolysis secondary to hyperthermia.

Choque séptico: Actualización en la monitorización hemodinámica / Septic shock in ICU: update in hemodynamic monitoring

Si bien los principios básicos para el diagnóstico y la monitorización hemodinámica como los pilares terapéuticos del niño con choque séptico se mantienen en el tiempo, es innegable que en las últimas décadas se han incorporado nuevos y trascendentes conceptos, por lo que es importante que el médico tratante de las unidades de cuidados intensivos tenga conocimiento de ellos a cabalidad. La monitorización hemodinámica es una herramienta que no solamente permite detectar el origen de la inestabilidad hemodinámica sino también guiar el tratamiento y evaluar su efectividad. La resucitación con fluidos debe ser el primer paso en la reanimación del paciente hemodinámicamente inestable. Sin embargo, la determinación clínica del volumen intravascular puede ser, en ocasiones, difícil de establecer en el paciente crítico. Las presiones de llenado cardiaco no son capaces de predecir la respuesta a fluidos. Los indicadores dinámicos de respuesta a fluidos evalúan el cambio en el volumen eyectivo durante la ventilación mecánica; de este modo, se valora la curva de Frank-Starling del paciente. Mediante la prueba de fluido es posible evaluar el grado de la reserva de precarga que se puede utilizar para aumentar el volumen eyectivo. En esta revisión se actualiza la información disponible sobre la monitorización hemodinámica básica y funcional.

In recent decades, new and important concepts have emerged for the diagnosis and management of the pediatric patient with septic shock, although the basic principles have remained similar over time. Attending physicians in the pediatric intensive care unit (PICU) must be fully aware of these concepts in order to improve patient care in the critical care unit. Hemodynamic monitoring is a tool that not only allows detection of the source of hemodynamic instability but also guides treatment and assesses its effectiveness. Fluid loading is considered the first step in the resuscitation of hemodynamically unstable patients. Nevertheless, clinical determination of the intravascular volume can be extremely difficult in a critically ill patient. Studies performed have demonstrated that cardiac filling pressures are unable to predict fluid responsiveness. Dynamic tests of volume responsiveness use the change in stroke volume during mechanical ventilation assessing the patients' Frank-Starling curve. Through fluid challenge the clinician can assess whether the patient has a preload reserve that can be used to increase the stroke volume. In this review we updated the available information on basic and functional hemodynamic monitoring.

Mild hypothermia increases pulmonary anti-inflammatory response during protective mechanical ventilation in a piglet model of acute lung injury.

BACKGROUND: The effects of mild hypothermia (HT) on acute lung injury (ALI) are unknown in species with metabolic rate similar to that of humans, receiving protective mechanical ventilation (MV). We hypothesized that mild hypothermia would attenuate pulmonary and systemic inflammatory responses in piglets with ALI managed with a protective MV. METHODS: Acute lung injury (ALI) was induced with surfactant deactivation in 38 piglets. The animals were then ventilated with low tidal volume, moderate positive end-expiratory pressure (PEEP), and permissive hypercapnia throughout the experiment. Subjects were randomized to HT (33.5°C) or normothermia (37°C) groups over 4 h. Plasma and tissue cytokines, tissue apoptosis, lung mechanics, pulmonary vascular permeability, hemodynamic, and coagulation were evaluated. RESULTS: Lung interleukin-10 concentrations were higher in subjects that underwent HT after ALI induction than in those that maintained normothermia. No difference was found in other systemic and tissue cytokines. HT did not induce lung or kidney tissue apoptosis or influence lung mechanics or markers of pulmonary vascular permeability. Heart rate, cardiac output, oxygen uptake, and delivery were significantly lower in subjects that underwent HT, but no difference in arterial lactate, central venous oxygen saturation, and coagulation test was observed. CONCLUSIONS: Mild hypothermia induced a local anti-inflammatory response in the lungs, without affecting lung function or coagulation, in this piglet model of ALI. The HT group had lower cardiac output without signs of global dysoxia, suggesting an adaptation to the decrease in oxygen uptake and delivery. Studies are needed to determine the therapeutic role of HT in ALI.

Surfactant deactivation in a pediatric model induces hypovolemia and fluid shift to the extravascular lung compartment.

BACKGROUND: Surfactant deficiency is the pivotal abnormality in Neonatal and Acute Respiratory Distress Syndrome. Surfactant deactivation can produce hypoxemia, loss of lung compliance, and pulmonary edema, but its circulatory consequences are less understood. OBJECTIVE: To describe the sequential hemodynamic changes and pulmonary edema formation after surfactant deactivation in piglets. METHODS: Surfactant deactivation was induced by tracheal instillation of polysorbate 20 in 15 anesthetized and mechanically ventilated Large White piglets. The hemodynamic consequences of surfactant deactivation were assessed at 30, 120, and 240 min by transpulmonary thermodilution and traditional methods. RESULTS: Surfactant deactivation caused hypoxemia, reduced lung compliance, and progressively increased lung water content (P < 0.01). Early hypovolemia was observed, with reductions of the global end-diastolic volume and stroke volume (P < 0.05). Reduced cardiac output was observed at the end of the study (P < 0.05). Standard monitoring was unable to detect these early preload alterations. Surprisingly, the bronchoalveolar protein content was greatly increased at the end of the study compared with baseline levels (P < 0.01). This finding was inconsistent with the notion that the pulmonary edema induced by surfactant deactivation was exclusively caused by high surface tension. CONCLUSIONS: Hypovolemia develops early after surfactant deactivation, in part due to the resulting fluid shift from the intravascular compartment to the lungs.