Riesgo de Retención de Secreciones en Pacientes con Ventilación Mecánica Invasiva / Risk of Retention of Secretions in Patients with Invasive Mechanical Ventilation

Introducción. Los pacientes conectados a ventilación mecánica invasiva pueden presentar complicaciones respiratorias, donde la retención de secreciones es una de las más frecuentes. El drenaje y eliminación de las secreciones depende entre otras variables de los flujos respiratorios generados, donde una diferencia absoluta entre el flujo espiratorio máximo (FEM) y flujo inspiratorio máximo (FIM) menor a 17 L•min-1 o una relación FIM/FEM mayor a 0.9 favorecerían la retención de secreciones. Sin embargo, falta por determinar los flujos respiratorios resultantes y la proporción de pacientes con riesgo de retención de secreciones según estos parámetros. Objetivo. Determinar los flujos respiratorios durante la ventilación mecánica invasiva y la proporción de pacientes que se encuentra en riesgo de retención de secreciones. Métodos. Estudio descriptivo transversal desarrollado en la Unidad de Paciente Crítico Médico-Quirúrgico del "Hospital Clínico de la Red de Salud UC-CHRISTUS". Se incluyeron pacientes adultos intubados y conectados a ventilación mecánica, en quienes se determinó los flujos respiratorios resultantes y se estimó la diferencia absoluta FEM-FIM, la relación FIM/FEM y la proporción de pacientes con riesgo de retención de secreciones. Resultados. Se incluyeron 100 pacientes, 45% presentaba entre sus diagnósticos patología respiratoria. La mediana de la diferencia absoluta entre FEM y FIM fue de 6 L•min-1 (-5 - 14.5) y la mediana de la tasa FIM/FEM de 0.87 (0.7 - 1.13). Un 84% presentó una diferencia absoluta entre FEM y FIM menor a 17 L•min-1, mientras que el 46% presentó una relación FIM/FEM mayor a 0.9. Conclusión. Una alta proporción de pacientes conectados a ventilación mecánica presenta riesgo de retención de secreciones independiente de la presencia o ausencia de patología respiratoria. Se requieren futuras investigaciones para evaluar el impacto de este criterio sobre complicaciones respiratorias.

Background. Patients connected to invasive mechanical ventilation may develop respiratory complications, where retention of secretions is one of the most frequent. The drainage and elimination of the secretions depend on other variables of the respiratory flows generated, where an absolute difference between the peak expiratory flow (PEF) and peak inspiratory flow (PIF) less than 17 L•min-1 or a PIF/PEF ratio greater than 0.9 would favor secretion retention. However, it is necessary to determine the respiratory flows and the proportion of patients, with and without respiratory pathology, with a risk of secretions retention according to these parameters. Objective. Determine respiratory flows during connection to invasive mechanical ventilation and the proportion of patients with and without respiratory pathology at risk of secretions retention. Methods. A descriptive cross-sectional study was conducted in the Medical-Surgical Intensive Care Unit of the "Hospital Clínico de la Red de Salud UC-CHRISTUS". Intubated adult patients connected to mechanical ventilation were included, in whom the respiratory flows were assessed, and the absolute PEF-PIF difference, PIF/PEF ratio, and the proportion of patients with a risk of secretions retention were determined. Results. 100 patients were included, of which 45% presented among their diagnoses acute or chronic respiratory pathology. For the total number of patients, the median of the absolute difference between PEF and PIF was 6 L•min-1 (-5 - 14.5), and the median of the PIF/PEF ratio of 0.87 (0.7 - 1.13). Of the total of patients, 84% presented an absolute difference between PEF and PIF less than 17 L• min-1, while 46% presented a PIF/PEF ratio greater than 0.9. Conclusion. Considering the absolute difference between PEF-PIF and the PIF/PEF ratio, many patients present a risk of secretions retention. However, whether this is associated with severe respiratory complications in patients connected to invasive mechanical ventilation should be clarified in future research.

Improve sleep in critically ill patients: Study protocol for a randomized controlled trial for a multi-component intervention of environment control in the ICU.

INTRODUCTION: In critically ill patients, sleep and circadian rhythms are greatly altered. These disturbances have been associated with adverse consequences, including increased mortality. Factors associated with the ICU environment, such as exposure to inadequate light and noise levels during the day and night or inflexible schedules of daily care activities, have been described as playing an essential role in sleep disturbances. The main objective of this study is to evaluate the impact of the use of a multifaceted environmental control intervention in the ICU on the quantity and quality of sleep, delirium, and post-intensive care neuropsychological impairment in critically ill patients. METHODS: This is a prospective, parallel-group, randomized trial in 56 critically ill patients once they are starting to recover from their acute illness. Patients will be randomized to receive a multifaceted intervention of environmental control in the ICU (dynamic light therapy, auditory masking, and rationalization of ICU nocturnal patient care activities) or standard care. The protocol will be applied from enrollment until ICU discharge. Baseline parameters, light and noise levels, polysomnography and actigraphy, daily oscillation of plasma concentrations of Melatonin and Cortisol, and questionnaires for the qualitative evaluation of sleep, will be assessed during the study. In addition, all patients will undergo standardized follow-up before hospital discharge and at 6 months to evaluate neuropsychological impairment. DISCUSSION: This study is the first randomized clinical trial in critically ill patients to evaluate the effect of a multicomponent, non-pharmacological environmental control intervention on sleep improvement in ICU patients. The results will provide data about the potential synergistic effects of a combined multi-component environmental intervention in ICU on outcomes in the ICU and long term, and the mechanism of action. TRIAL REGISTRATION: ClinicalTrials.gov, NCT. Registered on January 10, 2023. Last updated on 24 Jan 2023.

Remote, asynchronous training and feedback enables development of neurodynamic skills in physiotherapy students.

BACKGROUND: During the COVID-19 pandemic, face-to-face teaching and learning of physiotherapy practical skills was limited. Asynchronous, remote training has been effective in development of clinical skills in some health professions. This study aimed to determine the effect of remote, asynchronous training and feedback on development of neurodynamic skills in physiotherapy students. METHODS: Longitudinal repeated measurements study, across four training sessions. Participants engaged in a remote training program for development of upper limb neurodynamic techniques. In this sequential training, participants viewed the online tutorial, practiced independently, and uploaded a video of their performance for formative assessment and feedback from a trained instructor via a checklist and rubric. RESULTS: Intra-subject analyses of 60 third-year physiotherapy students showed that the target standard of performance, with no further significant change in scores, was attained following session 2 for the checklist and session 3 for the rubric. This shows that two sessions are required to learn the procedures, and three sessions yield further improvements in performance quality. CONCLUSION: The remote, asynchronous training and feedback model proved to be an effective strategy for students' development of neurodynamic testing skills and forms a viable alternative to in-person training. This study contributes to the future of acquiring physiotherapy clinical competencies when distance or hybrid practice is required.

Classification, quality characteristics, sensory perception and texture prediction of wooden breast myopathy in broilers from Argentina.

The objective of this study was to characterize the wooden breast (WB) myopathy in the poultry industry, and establish degrees of severity by analyzing the composition and important characteristics of meat quality. 175 chickens from the COBB-500 commercial line were analyzed, and three WB categories were established: normal, moderate, and severe. The prevalence was: 4.00% severe, 46.29% moderate, and 49.71% normal, and it was affected by sex and weight. The WB characterization was carried out on 7 breasts of each WB degree. A decrease in protein and ashes, an increase in fat and loss of water by dripping, and color changes were observed as the degree of severity advanced. The texture was evaluated by instrumental, sensory, and image analysis techniques. Severe samples showed alterations in compression test, cohesiveness and juiciness, together with significant differences on the parameters, "contrast" and "energy". A characterization of WB myopathy was achieved for the first time in Argentina. The decline in meat quality could lead to industrial losses. Image analysis proved to be a promising technique for differentiating the severity of WB myopathy in raw chicken. Differences between raw and cooked samples were detected, thus both types of meat should be studied in detail. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05608-9.

[Evaluation dosing intravenous voriconazole three times a day vs twice daily for the treatment of invasive aspergillosis in immunocompromised children: therapeutic drugs monitoring and safety]. / Evaluación de la dosificación de voriconazol intravenoso tres veces al día vs dos veces al día para el tratamiento de aspergilosis invasora en niños inmunocomprometidos: monitorización terapéutica y seguridad.

BACKGROUND: Voriconazole is the antifungal of choice for the treatment of invasive aspergillosis (IA). Plasma concentrations (PCs) > 1 µg / mL llave been associated with better therapeutic results which have not always been achieved during treatment in immunocompromised children. In the necessity to initiate early and effective therapy for the infection, it is relevant to establish the voriconazole administration regimen that is associated with optimal PCs in this population. AIM: To compare the PC and safety of intravenous (IV) voriconazole, dosed BID and TID in immunocompromised children with indication of antifungal treatment. METHOD: Retrospective observational study since January 2015 until July 2018 in a highly complex pediatric hospital in Santiago of Chile, in patients aged 0 to 17 years who received treatment with IV voriconazole. Those with renal replacement therapy, liver failure and / or renal failure were excluded. Trough PCs were compared between a group with BID dosing regimen versus another group with TID administration. Adverse reactions were evaluated in both groups. RESULTS: 137 trough PCs were obtained in 76 children, with a median age of 9 years (0-17 years) in the BID group and 9 years (0-16) in the TID group with a median weight of 27 kg (6-83 kg) and 28 kg (9.3-60 kg), respectively. Patients < 12 years old exposed to TID dosages are 4.65 times (OR: 4.65, 95% CI 1.93-11.2) more likely to have PC > 1 gg/mL compared to BID administration (p = 0.001). Eight adverse reactions were reported, mainly photophobia, with no significant difference found between the BID and TID groups. CONCLUSION: TID dosages are associated with a greater probability of obtaining adequate exposure to voriconazole in patients < 12 years old compared to BID dosages, with a low frequency of adverse reactions.

Evaluación de la dosificación de voriconazol intravenoso tres veces al día vs dos veces al día para el tratamiento de aspergilosis invasora en niños inmunocomprometidos: monitorización terapéutica y seguridad / Evaluation dosing intravenous voriconazole three times a day vs twice daily for the treatment of invasive aspergillosis in immunocompromised children: therapeutic drugs monitoring and safety

INTRODUCCIÓN: Voriconazol es el antifúngico de elección para el tratamiento de la aspergilosis invasora (AI). Concentraciones plasmáticas (CPs) > 1 μg/mL se han asociado a mejores resultados terapéuticos, las que no siempre se alcanzan durante el tratamiento en niños inmunocomprometidos. Dada la necesidad de iniciar una terapia precoz y efectiva de la infección, es relevante establecer el régimen de administración de voriconazol que se asocie con CPs óptimas en esta población. OBJETIVO: Comparar las CPs y seguridad de voriconazol intravenoso (IV), dosificado BID y TID en niños inmunocomprometidos con indicación de tratamiento antifúngico. MÉTODO: Estudio observacional retrospectivo de enero de 2015 a julio de 2018 en un hospital pediátrico de alta complejidad de Santiago de Chile, en pacientes de 0 a 17 años que recibieron tratamiento con voriconazol IV. Se excluyeron aquellos con terapia de reemplazo renal, falla hepática y/o falla renal. Se compararon las CPs valles entre un grupo con régimen de dosificación BID y otro grupo con administración TID. Se evaluaron las reacciones adversas en ambos grupos. RESULTADOS: Se obtuvieron 137 CPs valles en 76 niños, con una mediana de edad de 9 años (0-17 años) en el grupo BID y 9 años (0-16 años) en el grupo TID, con una mediana de peso de 27 kg (6-83 kg) y 28 kg (9,3-60 kg), respectivamente. Resultados: Pacientes 1 gg/mL en comparación con la administración BID (p = 0,001). Se reportaron ocho reacciones adversas, principalmente fotofobia, sin encontrarse diferencias significativas entre grupo BID y TID. CONCLUSIÓN: Dosificaciones TID están asociadas a una mayor probabilidad de obtener una adecuada exposición a voriconazol en pacientes < 12 años en comparación a dosificaciones BID, con baja frecuencia de reacciones adversas.

BACKGROUND: Voriconazole is the antifungal of choice for the treatment of invasive aspergillosis (IA). Plasma concentrations (PCs) > 1 μg / mL llave been associated with better therapeutic results which have not always been achieved during treatment in immunocompromised children. In the necessity to initiate early and effective therapy for the infection, it is relevant to establish the voriconazole administration regimen that is associated with optimal PCs in this population. AIM: To compare the PC and safety of intravenous (IV) voriconazole, dosed BID and TID in immunocompromised children with indication of antifungal treatment. METHOD: Retrospective observational study since January 2015 until July 2018 in a highly complex pediatric hospital in Santiago of Chile, in patients aged 0 to 17 years who received treatment with IV voriconazole. Those with renal replacement therapy, liver failure and / or renal failure were excluded. Trough PCs were compared between a group with BID dosing regimen versus another group with TID administration. Adverse reactions were evaluated in both groups. RESULTS: 137 trough PCs were obtained in 76 children, with a median age of 9 years (0-17 years) in the BID group and 9 years (0-16) in the TID group with a median weight of 27 kg (6-83 kg) and 28 kg (9.3-60 kg), respectively. Patients 1 gg/mL compared to BID administration (p = 0.001). Eight adverse reactions were reported, mainly photophobia, with no significant difference found between the BID and TID groups. CONCLUSION: TID dosages are associated with a greater probability of obtaining adequate exposure to voriconazole in patients < 12 years old compared to BID dosages, with a low frequency of adverse reactions.

Effect of positive end-expiratory pressure on lung injury and haemodynamics during experimental acute respiratory distress syndrome treated with extracorporeal membrane oxygenation and near-apnoeic ventilation.

BACKGROUND: Lung rest has been recommended during extracorporeal membrane oxygenation (ECMO) for severe acute respiratory distress syndrome (ARDS). Whether positive end-expiratory pressure (PEEP) confers lung protection during ECMO for severe ARDS is unclear. We compared the effects of three different PEEP levels whilst applying near-apnoeic ventilation in a model of severe ARDS treated with ECMO. METHODS: Acute respiratory distress syndrome was induced in anaesthetised adult male pigs by repeated saline lavage and injurious ventilation for 1.5 h. After ECMO was commenced, the pigs received standardised near-apnoeic ventilation for 24 h to maintain similar driving pressures and were randomly assigned to PEEP of 0, 10, or 20 cm H2O (n=7 per group). Respiratory and haemodynamic data were collected throughout the study. Histological injury was assessed by a pathologist masked to PEEP allocation. Lung oedema was estimated by wet-to-dry-weight ratio. RESULTS: All pigs developed severe ARDS. Oxygenation on ECMO improved with PEEP of 10 or 20 cm H2O, but did not in pigs allocated to PEEP of 0 cm H2O. Haemodynamic collapse refractory to norepinephrine (n=4) and early death (n=3) occurred after PEEP 20 cm H2O. The severity of lung injury was lowest after PEEP of 10 cm H2O in both dependent and non-dependent lung regions, compared with PEEP of 0 or 20 cm H2O. A higher wet-to-dry-weight ratio, indicating worse lung injury, was observed with PEEP of 0 cm H2O. Histological assessment suggested that lung injury was minimised with PEEP of 10 cm H2O. CONCLUSIONS: During near-apnoeic ventilation and ECMO in experimental severe ARDS, 10 cm H2O PEEP minimised lung injury and improved gas exchange without compromising haemodynamic stability.

Prognostic Factors in De Novo Metastatic Renal Cell Carcinoma: A Report From the Latin American Renal Cancer Group.

PURPOSE: To assess the effect of clinical and pathological variables on cancer-specific and overall survival (OS) in de novo metastatic patients from a collaborative of primarily Latin American countries. PATIENTS AND METHODS: Of 4,060 patients with renal cell carcinoma diagnosed between 1990 and 2015, a total of 530 (14.5%) had metastasis at clinical presentation. Relationships between clinical and pathological parameters and treatment-related outcomes were analyzed by Cox regression and the log-rank method. RESULTS: Of 530 patients, 184 (90.6%) had died of renal cell carcinoma. The median OS of the entire cohort was 24 months. American Society of Anesthesiology classification 3-4 (hazard ratio [HR]: 1.64), perirenal fat invasion (HR: 2.02), and ≥ 2 metastatic organ sites (HR: 2.19) were independent prognostic factors for 5-year OS in multivariable analyses. We created a risk group stratification with these variables: no adverse risk factors (favorable group), median OS not reached; one adverse factor (intermediate group), median OS 33 months (HR: 2.04); and two or three adverse factors (poor risk group), median OS 14 months (HR: 3.58). CONCLUSION: Our study defines novel prognostic factors that are relevant to a Latin American cohort. With external validation, these easily discerned clinical variables can be used to offer prognostic information across low- and middle-income countries.

Low Spontaneous Breathing Effort during Extracorporeal Membrane Oxygenation in a Porcine Model of Severe Acute Respiratory Distress Syndrome.

BACKGROUND: A lung rest strategy is recommended during extracorporeal membrane oxygenation in severe acute respiratory distress syndrome (ARDS). However, spontaneous breathing modes are frequently used in this context. The impact of this approach may depend on the intensity of breathing efforts. The authors aimed to determine whether a low spontaneous breathing effort strategy increases lung injury, compared to a controlled near-apneic ventilation, in a porcine severe ARDS model assisted by extracorporeal membrane oxygenation. METHODS: Twelve female pigs were subjected to lung injury by repeated lavages, followed by 2-h injurious ventilation. Thereafter, animals were connected to venovenous extracorporeal membrane oxygenation and during the first 3 h, ventilated with near-apneic ventilation (positive end-expiratory pressure, 10 cm H2O; driving pressure, 10 cm H2O; respiratory rate, 5/min). Then, animals were allocated into (1) near-apneic ventilation, which continued with the previous ventilatory settings; and (2) spontaneous breathing: neuromuscular blockers were stopped, sweep gas flow was decreased until regaining spontaneous efforts, and ventilation was switched to pressure support mode (pressure support, 10 cm H2O; positive end-expiratory pressure, 10 cm H2O). In both groups, sweep gas flow was adjusted to keep Paco2 between 30 and 50 mmHg. Respiratory and hemodynamic as well as electric impedance tomography data were collected. After 24 h, animals were euthanized and lungs extracted for histologic tissue analysis. RESULTS: Compared to near-apneic group, the spontaneous breathing group exhibited a higher respiratory rate (52 ± 17 vs. 5 ± 0 breaths/min; mean difference, 47; 95% CI, 34 to 59; P < 0.001), but similar tidal volume (2.3 ± 0.8 vs. 2.8 ± 0.4 ml/kg; mean difference, 0.6; 95% CI, -0.4 to 1.4; P = 0.983). Extracorporeal membrane oxygenation settings and gas exchange were similar between groups. Dorsal ventilation was higher in the spontaneous breathing group. No differences were observed regarding histologic lung injury. CONCLUSIONS: In an animal model of severe ARDS supported with extracorporeal membrane oxygenation, spontaneous breathing characterized by low-intensity efforts, high respiratory rates, and very low tidal volumes did not result in increased lung injury compared to controlled near-apneic ventilation.

Razonamiento clínico en kinesiología mediante aprendizaje basado en casos / Clinical reasoning in kinesiology by case-based learning

Introducción: En cursos clínicos con gran número de estudiantes, las experiencias clínicas con pacientes reales son limitadas, dificul-tando el logro de objetivos de aprendizaje. La didáctica aprendizaje basado en casos (ABC) promueve el pensamiento crítico y trabajo coolaborativo, aspectos esenciales para desarrollar competencias profesionales. El objetivo de este estudio fue reportar si la incorpo-ración de la metodología ABC en una asignatura clínica curricular promueve el razonamiento clínico en la formación en kinesiología. Metodología: En la asignatura curricular "evaluación cardiorrespiratoria en kinesiología", 10 grupos de 7 estudiantes desarrollaron casos clínicos de temas disciplinares seleccionados bajo criterio de jueces por expertos del área, y lo presentaron al resto de sus compañeros. Un académico guió la reflexión del tema tratado en el ABC, fomentando la discusión entre los estudiantes. Al finalizar la asignatura se evaluó la percepción de la didáctica educativa mediante encuesta y logro de objetivos de aprendizaje con indicadores académicos. Resultados: Los estudiantes reportaron gran satisfacción con la metodología, mayor preparación para actividades de campo clínico y mejoras en sus habilidades comunicacionales. El promedio obtenido en las interrogaciones y en las actividades clínicas fue superior a versiones previas de la asignatura, aumentando el porcentaje de aprobación y satisfacción con el curso. Conclusión: La incorporación de la didáctica de ABC fomentó el razonamiento clínico, reflexión y habilidades comunicacionales mejorando el rendimiento académico y promoviendo competencias profesionales. Como producto final se elaboró un libro de descarga libre con los temas tratados en los ABC, titulado: "Identificando problemas kinesiológicos: aprendizaje basado en casos".

Introduction: In clinical courses with a large number of students, clinical experiences with real patients are limited, difficult to achieve the learning objectives. The 'Case-Based Learning' (CBL), like educational methodology, promotes critical thinking and improve collaborative work, which are essential aspects of the development of professional skills. The objective of this study was to report how the incorporation of the CBL methodology in a clinical course promoted the clinical reasoning in kinesiology students. Methodology: In the curriculum subject ten groups of seven students analyzed different clinical cases and presented them to their classmates. The CBL topics were selected by academic experts, who also guided and encouraged the discussion among the students. An online survey at the end of the course assessed perceptions students participated in this methodology. The final academic indicators assessed the learning objectives of the course achieved by students that participated with this methodology. Results: The students reported high satisfaction with the CBL methodology. They showed better preparation for clinical experiences and an improvement in their communication skills. The final marks obtained in the interrogations and the clinical practice activities were higher than in previous years. There was an increase in academic approval and student satisfaction with the course. Conclusion: The incorporation of the CBL methodology enhanced clinical reasoning, reflection, and communication skills, improving academic performance, and promoting professional skills. The topics covered in the CBLs conformed a free download book, entitled: «Identifying kinesiology problems: case-based learning.

Fichas clínicas simuladas en kinesiología / Simulated clinical records in kinesiology

Introducción: la normativa actual de docencia clínica regula el desarrollo de actividades curriculares disminuyendo el tiempo de con-tacto estudiante-paciente, requiriendo entre otras destrezas del estudiante la lectura eficiente de información clínica. La simulación permite desarrollar competencias clínicas en los estudiantes de ciencias de la salud. El objetivo de este estudio es describir la experiencia de talleres de fichas clínicas simuladas (FCS) en estudiantes curriculares y reportar indicadores de logro de objetivos de aprendizaje relacionados al reconocimiento de las partes de la ficha clínica e identificación y extracción de información relevante. Metodología: en una asignatura de carácter mínimo previo al encuentro de estudiantes con pacientes reales, se desarrollaron cuatro talleres de FCS en grupo pequeño. Un académico guió la actividad consistente en responder cuestionarios de ubicación de información presente en las FCS. Al finalizar la asignatura, se evaluó la percepción de la didáctica educativa y logro de objetivos de aprendizaje en tutores clínicos y estudiantes mediante encuesta. Resultados: los estudiantes reportaron alta satisfacción con la metodología, facilidad para extraer información relevante y mayor tiempo de contacto clínico con pacientes reales. Los tutores clínicos informaron que los estudiantes logran reconocer las partes de la ficha clínica. Ambos consideran que el tiempo ideal para lectura de ficha clínica es de 10 a 20 minutos.Conclusión: la incorporación de talleres de fichas clínicas simuladas desarrolló habilidades clínicas de reconocimiento de las partes que componen la ficha clínica, optimizando el tiempo necesario para identificar y extraer información relevante a diferentes escenarios clínicos.

Reliability of NIRS portable device for measuring intercostal muscles oxygenation during exercise.

This study assessed the intra-individual reliability of oxygen saturation in intercostal muscles (SmO2-m.intercostales) during an incremental maximal treadmill exercise by using portable NIRS devices in a test-retest study. Fifteen marathon runners (age, 24.9 ± 2.0 years; body mass index, 21.6 ± 2.3 kg·m-2; V̇O2-peak, 63.7 ± 5.9 mL·kg-1·min-1) were tested on two separate days, with a 7-day interval between the two measurements. Oxygen consumption (V̇O2) was assessed using the breath-by-breath method during the V̇O2-test, while SmO2 was determined using a portable commercial device, based in the near-infrared spectroscopy (NIRS) principle. The minute ventilation (VE), respiratory rate (RR), and tidal volume (Vt) were also monitored during the cardiopulmonary exercise test. For the SmO2-m.intercostales, the intraclass correlation coefficient (ICC) at rest, first (VT1) and second ventilatory (VT2) thresholds, and maximal stages were 0.90, 0.84, 0.92, and 0.93, respectively; the confidence intervals ranged from -10.8% - +9.5% to -15.3% - +12.5%. The reliability was good at low intensity (rest and VT1) and excellent at high intensity (VT2 and max). The Spearman correlation test revealed (p ≤ 0.001) an inverse association of SmO2-m.intercostales with V̇O2 (ρ = -0.64), VE (ρ = -0.73), RR (ρ = -0.70), and Vt (ρ = -0.63). The relationship with the ventilatory variables showed that increased breathing effort during exercise could be registered adequately using a NIRS portable device.

Near-Apneic Ventilation Decreases Lung Injury and Fibroproliferation in an Acute Respiratory Distress Syndrome Model with Extracorporeal Membrane Oxygenation.

RATIONALE: There is wide variability in mechanical ventilation settings during extracorporeal membrane oxygenation (ECMO) in patients with acute respiratory distress syndrome. Although lung rest is recommended to prevent further injury, there is no evidence to support it. OBJECTIVES: To determine whether near-apneic ventilation decreases lung injury in a pig model of acute respiratory distress syndrome supported with ECMO. METHODS: Pigs (26-36 kg; n = 24) were anesthetized and connected to mechanical ventilation. In 18 animals lung injury was induced by a double-hit consisting of repeated saline lavages followed by 2 hours of injurious ventilation. Then, animals were connected to high-flow venovenous ECMO, and randomized into three groups: 1) nonprotective (positive end-expiratory pressure [PEEP], 5 cm H2O; Vt, 10 ml/kg; respiratory rate, 20 bpm), 2) conventional-protective (PEEP, 10 cm H2O; Vt, 6 ml/kg; respiratory rate, 20 bpm), and 3) near-apneic (PEEP, 10 cm H2O; driving pressure, 10 cm H2O; respiratory rate, 5 bpm). Six other pigs were used as sham. All groups were maintained during the 24-hour study period. MEASUREMENTS AND MAIN RESULTS: Minute ventilation and mechanical power were lower in the near-apneic group, but no differences were observed in oxygenation or compliance. Lung histology revealed less injury in the near-apneic group. Extensive immunohistochemical staining for myofibroblasts and procollagen III was observed in the nonprotective group, with the near-apneic group exhibiting the least alterations. Near-apneic group showed significantly less matrix metalloproteinase-2 and -9 activity. Histologic lung injury and fibroproliferation scores were positively correlated with driving pressure and mechanical power. CONCLUSIONS: In an acute respiratory distress syndrome model supported with ECMO, near-apneic ventilation decreased histologic lung injury and matrix metalloproteinase activity, and prevented the expression of myofibroblast markers.

Evaluación del trabajo respiratorio mediante oxigenación muscular / Assessment of work of breathing using muscle oxygenation

RESUMEN El aumento del trabajo respiratorio (work of breathing, WOB) es uno de los problemas kinesiológicos frecuentes en el quehacer clínico. Un desafío profesional es contar con valores de variables fisiológicas que permitan objetivar el WOB facilitando así su interpretación entre los diferentes profesionales de la salud. El uso de dispositivos portátiles que registran la longitud de onda cercana al rango infrarrojo (680- 820 nm, Near Infrared Spectroscopy (NIRS)) en músculos superficiales permite obtener valores de hemoglobina total unida a oxígeno (tHb) y oxigenación muscular local (SmO2), variables relacionadas al trabajo muscular pues reportan el flujo sanguíneo en la microcirculación y consumo de oxígeno local, respectivamente. Estos dispositivos situados en musculatura intercostal nos informan el WOB asociado a la respiración. Para evaluar esto, se analizó el comportamiento de tHb y SmO2 en m. intercostal en 20 corredores de maratón durante la valoración de consumo de oxígeno máximo (VO2- max), instancia que implica aumento sostenido e incremental de la ventilación pulmonar (��E), y por tanto de la actividad muscular respiratoria. El aumento de V E en 128,4 L·min-1 ( ��E (máximo-reposo)) implicó una disminución en SmO2- m.intercostal del 34% ( SmO2 (reposo-máximo)), sin cambios en tHb (p=0,805). La tuvo una correlación inversa con SmO2-m.intercostal (rho=-0.565; p=0,001). Se concluye que la valoración de SmO2-m.intercostal es una forma novedosa de objetivar el WOB en sujetos sanos. Conocer la aplicabilidad clínica requiere de otros estudios que evalúen esta herramienta en pacientes con disfunciones cardiorrespiratorias, lo que permitiría incorporar su uso en nuestro desarrollo clínico profesional.

The work of breathing (WOB) increased is a commonkinesiological problems at the clinical practice. A professional challenge is to have values of physiological variables that allows to objective the WOB, thus facilitating its interpretation among different health professionals. The use of portable devices that measure by spectroscopy the near-infrared wavelength (680-820 nm) atsuperficial muscles allows to obtain values of total hemoglobin linked to oxygen (tHb) and local muscle oxygenation (SmO2), variables related to muscle work because give information of the blood flow at the microcirculation and local oxygen consumption, respectively. These devices located at the m.intercostal could give information about the WOB associated to breathing. To evaluate this, the tHb and SmO2 of the m.intercostal in 20 marathon runners were analyzed while they doing the maximum oxygen consumption test (VO2-max), an exercise that increase the pulmonary ventilation and the respiratory muscle activity. The increase of V E (128,4 L·min-1((max-rest)) implied a decrease in SmO2- m.intercostal (34% ( SmO2 (max-rest)), without changes in tHb (p=0.805). The showedan negative correlation to SmO2-m.intercostal (rho= -0.565; p=0.001). It is concluded that the assessment of SmO2-m.intercostal is a novel way to measure the WOB in healthy subjects. Their clinical applicability requires more studies that applied this tool in patients with cardiorespiratory dysfunctions, facilitating their incorporation in the professional clinical practice.

[Pharmacokinetics of posaconazol in the prophylaxis and treatment of invasive fungal infection in immunocompromised children in a pediatric hospital]. / Farmacocinética de posaconazol en la profilaxis y tratamiento de la infección fúngica invasora en niños inmunocomprometidos en un hospital pediátrico.

Background There is no consensus on the optimal dosage use of posaconazole (PSC) for invasive fungal infection (IFI) in pediatric patients and normally it is adjusted with drug levels (DLs) ≥ 0.7 µg/ml and ≥ 1.25 µg/ml for prophylaxis and treatment, respectively. Objective To describe the experience of monitoring DLs of PSC in immunocompromised pediatric patients with IFI and to determine if the recommended doses reach CP effective in prophylaxis (≥ 0.7 µg/mL) and treatment (≥ 1.25 µg/mL). Method A retrospective analysis in children who received PSC from January 2012 to October 2016, in the Oncology and Bone Marrow Transplant units at Hospital Calvo Mackenna was done Six patients with 78 DLs were reviewed (4 prophylaxis and 4 treatment). Median PSC dose was 12.5 and 18.8 mg/kg/d for prophylaxis and treatment, resulting in mean DLs of 0.97 and 1.8 µg/mL respectively. In prophylaxis 40/67 (60%) were recorded with DLs ≥ 0.70 µg/mL receiving a median dose of 12.5 mg/kg/d. While for treatment: 5/11 (46%) presented DLs ≥ 1.25 µg/mL, receiving a median dose of 18 mg/kg/d. Conclusion Our results are in line with the recommended for PSC dosage, but individualized monitoring is required to maintain adequate DLs.

Farmacocinética de posaconazol en la profilaxis y tratamiento de la infección fúngica invasora en niños inmunocomprometidos en un hospital pediátrico / Pharmacokinetics of posaconazol in the prophylaxis and treatment of invasive fungal infection in immunocompromised children in a pediatric hospital

Resumen Introducción En pediatría no existe consenso en la dosificación de posaconazol (PSC) para profilaxis y tratamiento de la infección fúngica invasora (IFI), usándose la medición de concentraciones plasmáticas (CPs) del fármaco. Objetivo Describir la experiencia de monitoreo de las CPs de PSC en niños inmunocomprometidos con IFI y determinar si las dosis recomendadas alcanzan CPs efectivas en profilaxis (≥ 0,7 µg/mL) y tratamiento (≥ 1,25 µg/mL). Método Análisis retrospectivo en niños que recibieron PSC suspensión como profilaxis o tratamiento entre enero de 2012 y octubre de 2016, en las unidades de Oncología y Trasplante de Médula Ósea del Hospital Calvo Mackenna. Resultados 78 CPs en seis pacientes (4 indicaciones de profilaxis y 4 tratamientos) fueron revisados. La mediana de dosis de PSC fue de 12,5 y 18,8 mg/kg/d para profilaxis y tratamiento, respectivamente, resultando CP mediana de 0,97 y 1,8 μg/mL, respectivamente. En profilaxis, se registraron 40/67 (60%) con CP ≥ 0,70 μg/mL recibiendo una mediana de dosis de 12,5 mg/kg/d. Mientras que para el tratamiento: 5/11 (46%), presentaron CP ≥ 1,25 μg/mL, recibiendo una mediana de dosis de 18 mg/kg/d. Conclusión Nuestros resultados se ajustan a lo recomendado para la dosificación de PSC, pero evidencian una necesidad de realizar una monitorización individualizada para mantener adecuadas CPs.

Background There is no consensus on the optimal dosage use of posaconazole (PSC) for invasive fungal infection (IFI) in pediatric patients and normally it is adjusted with drug levels (DLs) ≥ 0.7 μg/ml and ≥ 1.25 μg/ml for prophylaxis and treatment, respectively. Objective To describe the experience of monitoring DLs of PSC in immunocompromised pediatric patients with IFI and to determine if the recommended doses reach CP effective in prophylaxis (≥ 0.7 μg/mL) and treatment (≥ 1.25 μg/mL). Method A retrospective analysis in children who received PSC from January 2012 to October 2016, in the Oncology and Bone Marrow Transplant units at Hospital Calvo Mackenna was done Six patients with 78 DLs were reviewed (4 prophylaxis and 4 treatment). Median PSC dose was 12.5 and 18.8 mg/kg/d for prophylaxis and treatment, resulting in mean DLs of 0.97 and 1.8 μg/mL respectively. In prophylaxis 40/67 (60%) were recorded with DLs ≥ 0.70 μg/mL receiving a median dose of 12.5 mg/kg/d. While for treatment: 5/11 (46%) presented DLs ≥ 1.25 μg/mL, receiving a median dose of 18 mg/kg/d. Conclusion Our results are in line with the recommended for PSC dosage, but individualized monitoring is required to maintain adequate DLs.

Extracorporeal membrane oxygenation improves survival in a novel 24-hour pig model of severe acute respiratory distress syndrome.

Extracorporeal membrane oxygenation (ECMO) is increasingly being used to treat severe acute respiratory distress syndrome (ARDS). However, there is limited clinical evidence about how to optimize the technique. Experimental research can provide an alternative to fill the actual knowledge gap. The purpose of the present study was to develop and validate an animal model of acute lung injury (ALI) which resembled severe ARDS, and which could be successfully supported with ECMO. Eighteen pigs were randomly allocated into three groups: sham, ALI, and ALI + ECMO. ALI was induced by a double-hit consisting in repeated saline lavage followed by a 2-hour period of injurious ventilation. All animals were followed up to 24 hours while being ventilated with conventional ventilation (tidal volume 10 ml/kg). The lung injury model resulted in severe hypoxemia, increased airway pressures, pulmonary hypertension, and altered alveolar membrane barrier function, as indicated by an increased protein concentration in bronchoalveolar fluid, and increased wet/dry lung weight ratio. Histologic examination revealed severe diffuse alveolar damage, characteristic of ARDS. Veno-venous ECMO was started at the end of lung injury induction with a flow > 60 ml/kg/min resulting in rapid reversal of hypoxemia and pulmonary hypertension. Mortality was 0, 66.6 and 16.6% in the SHAM, ALI and ALI + ECMO groups, respectively (p < 0.05). This is a novel clinically relevant animal model that can be used to optimize the approach to ECMO and foster translational research in extracorporeal lung support.

Fenotipos neurológicos en pacientes estudiados con citogenética en el Hospital de Puerto Montt / Neurological phenotypes in cytogenic study from Puerto Montt Hospital patients

El examen citogenético, es una herramienta importante para confirmar el diagnóstico, manejo y consejo genético. El objetivo es analizar las características del fenotipo neuroconductual, protocolizar y orientar en la eficaz solicitud del estudio citogenético. Se revisaron las fichas clínicas de los pacientes controlados del policlínico de Neuropediatría del Hospital de Puerto Montt, con cariograma anormal entre los años 2007 y 2012. De 248 pacientes, 12% se identificó una alteración; 58% aberraciones estructurales, 20% aneuploidías, y 20% alteraciones genético - moleculares. Los elementos clínicos que se encontraron fueron microcefalia 48%, retraso mental 67%, historia familiar 67%, hipotonía 70%, convulsiones 41%, alteraciones del SNC 37%.

Cytogenetic examination is an important tool for confirming diagnosis, case management and genetic counseling. The aim is to analyze the characteristics of neurobehavioral phenotypes, formalize and guide the effective application of cytogenetics. The medical records of patients with abnormal karyotype seen between 2007 and 2012 at the Hospital of Puerto Montt's neuropaediatric outpatient clinic were reviewed. Of 248 patients, in 12% an alteration was identified; 58% structural aberrations, 20% aneuploidy, and 20% genetic-molecular alterations. The clinical elements found were 48% microcephaly, 67% mental retardation, 67% family history, 70% hypotonia, 41% seizures, 37% CNS disorders.

Enseñanza de la bioética en el currículo de las carreras de odontología desde la perspectiva de los estudiantes / Ensino da bioética no currículo dos cursos de odontologia sob a perspectiva dos estudantes / Training on bioethics in dentistry curriculum from the perspective of students

Se realizó un estudio de tipo descriptivo, a través del análisis de contenido, con la finalidad de conocer las percepciones de los estudiantes de odontología sobre la enseñanza de la bioética en el currículo de la carrera de Odontología de la Universidad de la Frontera. La recolección de los datos se realizó mediante la técnica de grupos focales, en dos sesiones de doce alumnos cada uno, representados por dos alumnos de los diferentes niveles de la carrera. La interrelación entre los participantes se estimuló a través de una pauta de conducción previamente diseñada. Los datos, registrados a través de grabaciones, fueron transcritos para el análisis de contenido, efectuado manualmente mediante triangulación entre los investigadores. A partir del análisis de contenido de los datos primarios, se estableció una serie de categorías, agrupadas en cuatro grandes dimensiones: concepto de bioética, importancia de la bioética en el ejercicio profesional, enseñanza-aprendizaje de la bioética y modalidad de enseñanza de la bioética. Los estudiantes de odontología de la Universidad de la Frontera transitan de manera muy asertiva por los tópicos que componen la compleja dimensión de la enseñanza de la bioética y reconocen la importancia de la bioética en su formación.

A descriptive study was carried out through content analysis, with the goal of knowing the perceptions of dentistry students about bioethics training in Dentistry curriculum of Frontera University. Data collected was carried out through focal group technique in two sessions of 12 students each, represented by two students from de different levels of the career. The interrelation among participants was stimulated through a guide for conduction previously designed. Data registered through tape recording were transcribed for content analysis, carried out manually by triangulation among researchers. Several categories were established by content analysis of primary data, grouped in four big dimensions: concept of bioethics, importance of bioethics in professional exercise, teaching-learning of bioethics and modality of teaching of bioethics. Dentistry students of Frontera University walked in assertive way through issues belonging to the complex dimension of bioethics training and recognize the importance of bioethics in their training.

Foi realizado um estudo de tipo descritivo, através da análise de conteúdo, com a finalidade de conhecer as percepções dos estudantes de odontologia sobre o ensino da bioética no currículo do curso de Odontologia da Universidad de laFrontera. A coleta dos dados foi realizada mediante a técnica de grupos focais, nas seções de doze alunos cada uma, representados por dois alunos dos diferentes níveis do curso. A inter-relação entre os participantes foi estimulada por meio de uma pauta de condução previamente projetada. Os dados, registrados através de gravações, foram transcritos para a análise de conteúdo, efetuado manualmente mediante triangulação entre os investigadores. A partir da análise de conteúdo dos dados primários, se estabeleceu uma série de categorias, agrupadas em quatro grandes dimensões: conceito de bioética, importância da bioética no exercício profissional, ensino-aprendizagem da bioética e modalidade de ensino da bioética. Os estudantes de odontologia da Universidad de laFrontera transitam de maneira muito assertiva pelos tópicos que compõem a complexa dimensão do ensino da bioética e reconhecem a importância da bioética em sua formação.