Síndrome do desconforto respiratório agudo relacionada à sepse em crianças com câncer: dinâmica respiratória de uma condição devastadora / Sepsis-related acute respiratory distress syndrome in children with cancer: the respiratory dynamics of a devastating condition

RESUMO Objetivo: Avaliar a evolução clínica e os parâmetros respiratórios de crianças com câncer submetidas à ventilação mecânica que apresentavam síndrome do desconforto respiratório agudo relacionada à sepse. Métodos: Este estudo longitudinal, prospectivo e observacional de coorte com duração de 2 anos incluiu 29 crianças e adolescentes. Dados clínicos, avaliações de gasometria sanguínea e parâmetros ventilatórios foram coletados em quatro momentos diferentes. As flutuações entre as avaliações e as diferenças entre as médias estimadas foram analisadas por meio de modelos lineares mistos, tendo como parâmetro primário (endpoint) a ocorrência de óbito dentro de 28 dias após o início da síndrome do desconforto respiratório agudo. Resultados: Ocorreram 17 óbitos dentro de 28 dias após o início da síndrome do desconforto respiratório agudo, e outros 7 entre 29 e 60 dias. Apenas cinco pacientes sobreviveram por mais de 60 dias. Nove (31%) pacientes faleceram como consequência direta de hipoxemia refratária, e os demais em razão de falência de múltiplos órgãos e choque refratário a catecolaminas. Em 66% das avaliações, o volume corrente demandado para obter saturação de oxigênio igual ou acima de 90% foi superior a 7mL/kg. As médias estimadas de complacência dinâmica foram baixas e similares para sobreviventes e não sobreviventes, porém com inclinação negativa da reta entre a primeira e última avaliações, acompanhada por uma inclinação negativa da reta para volume corrente nos não sobreviventes. Os não sobreviventes tiveram significantemente mais hipoxemia, com relações PaO2/FiO2 que demonstravam médias mais baixas e inclinação negativa da reta nas quatro avaliações. As pressões pico, expiratória e média das vias aéreas demonstraram inclinações positivas na reta para os não sobreviventes, que também apresentaram mais acidose metabólica. Conclusões: Na maioria de nossas crianças com câncer, a sepse e a síndrome do desconforto respiratório agudo evoluíram com deterioração dos índices ventilatórios e progressiva disfunção de órgãos, o que tornou esta tríade praticamente fatal em crianças.

ABSTRACT Objective: To evaluate the clinical course and respiratory parameters of mechanically ventilated children with cancer suffering from sepsis-related acute respiratory distress syndrome. Methods: This 2-year prospective, longitudinal, observational cohort study enrolled 29 children and adolescents. Clinical data, measurements of blood gases and ventilation parameters were collected at four different time points. Fluctuations between measurements as well as differences in estimated means were analyzed by linear mixed models in which death within 28 days from the onset of acute respiratory distress syndrome was the primary endpoint. Results: There were 17 deaths within 28 days of acute respiratory distress syndrome onset and another 7 between 29 - 60 days. Only 5 patients survived for more than 60 days. Nine (31%) patients died as a direct consequence of refractory hypoxemia, and the others died of multiple organ failure and catecholamine-refractory shock. In 66% of the measurements, the tidal volume required to obtain oxygen saturation equal to or above 90% was greater than 7mL/kg. The estimated means of dynamic compliance were low and were similar for survivors and non-survivors but with a negative slope between the first and final measurements, accompanied by a negative slope of the tidal volume for non-survivors. Non-survivors were significantly more hypoxemic, with PaO2/FiO2 ratios showing lower estimated means and a negative slope along the four measurements. Peak, expiratory and mean airway pressures showed positive slopes in the non-survivors, who also had more metabolic acidosis. Conclusions: In most of our children with cancer, sepsis and acute respiratory distress syndrome progressed with deteriorating ventilation indexes and escalating organic dysfunction, making this triad nearly fatal in children.

Decúbito prono en pacientes con síndrome de distrés respiratorio agudo / Prone position in patients with acute respiratory distress syndrome

RESUMEN El síndrome de distrés respiratorio agudo ocupa gran atención en la unidad de cuidados intensivos. A pesar del amplio conocimiento alcanzado sobre la fisiopatología de éste síndrome, el enfoque en la unidad de cuidados intensivos consiste, en gran parte, en un tratamiento de soporte vital y en evitar los efectos secundarios de las terapéuticas invasivas. Si bien, durante los últimos 20 años, se generaron grandes avances en ventilación mecánica con un impacto importante sobre la mortalidad, ésta continúa siendo elevada. Una característica de los pacientes con síndrome de distrés respiratorio agudo, sobre todo los más severos, es la presencia de hipoxemia refractaria debido a la existencia de shunt, pudiendo requerir tratamientos adicionales a la ventilación mecánica, entre ellos la ventilación mecánica en decúbito prono. Este método, recomendado para mejorar la oxigenación por primera vez en 1974, puede ser implementado fácilmente en cualquier unidad de cuidados intensivos con personal entrenado. El decúbito prono tiene un sustento bibliográfico sumamente robusto. Varios ensayos clínicos randomizados han demostrado el efecto del decúbito prono sobre la oxigenación en pacientes con síndrome de distrés respiratorio agudo medida a través de la relación PaO2/FiO2 e incluso su impacto en el aumento de la sobrevida de estos pacientes. Los integrantes del Comité de Kinesiología Intensivista de la Sociedad Argentina de Terapia Intensiva realizaron una revisión narrativa con el objetivo de exponer la evidencia disponible en relación a la implementación del decúbito prono, los cambios producidos en el sistema respiratorio por la aplicación de la maniobra y su impacto sobre la mortalidad. Por último, se sugerirán lineamientos para la toma de decisiones.

ABSTRACT Acute respiratory distress syndrome occupies a great deal of attention in intensive care units. Despite ample knowledge of the physiopathology of this syndrome, the focus in intensive care units consists mostly of life-supporting treatment and avoidance of the side effects of invasive treatments. Although great advances in mechanical ventilation have occurred in the past 20 years, with a significant impact on mortality, the incidence continues to be high. Patients with acute respiratory distress syndrome, especially the most severe cases, often present with refractory hypoxemia due to shunt, which can require additional treatments beyond mechanical ventilation, among which is mechanical ventilation in the prone position. This method, first recommended to improve oxygenation in 1974, can be easily implemented in any intensive care unit with trained personnel. Prone position has extremely robust bibliographic support. Various randomized clinical studies have demonstrated the effect of prone decubitus on the oxygenation of patients with acute respiratory distress syndrome measured in terms of the PaO2/FiO2 ratio, including its effects on increasing patient survival. The members of the Respiratory Therapists Committee of the Sociedad Argentina de Terapia Intensiva performed a narrative review with the objective of discovering the available evidence related to the implementation of prone position, changes produced in the respiratory system due to the application of this maneuver, and its impact on mortality. Finally, guidelines are suggested for decision-making.

Validity of Outcome Prediction Scoring Systems in Korean Patients with Severe Adult Respiratory Distress Syndrome Receiving Extracorporeal Membrane Oxygenation Therapy

Recently, several prognostic scoring systems for patients with severe acute respiratory distress syndrome (ARDS) requiring extracorporeal membrane oxygenation (ECMO) have been published. The aim of this study was to validate the established scoring systems for outcome prediction in Korean patients. We retrospectively reviewed the data of 50 patients on ECMO therapy in our center from 2012 to 2014. A calculation of outcome prediction scoring tools was performed and the comparison across various models was conducted. In our study, the overall hospital survival was 46% and successful weaning rate was 58%. The Predicting Death for Severe ARDS on V-V ECMO (PRESERVE) score showed good discrimination of mortality prediction for patients on ECMO with AUC of 0.80 (95% CI 0.66-0.90). The respiratory extracorporeal membrane oxygenation survival prediction (RESP) score and simplified acute physiology score (SAPS) II score also showed fair prediction ability with AUC of 0.79 (95% CI 0.65-0.89) and AUC of 0.78 (95% CI 0.64-0.88), respectively. However, the ECMOnet score failed to predict mortality with AUC of 0.51 (95% CI 0.37-0.66). When evaluating the predictive accuracy according to optimal cut-off point of each scoring system, RESP score had a best specificity of 91.3% and 66.7% of sensitivity, respectively. This study supports the clinical usefulness of the prognostic scoring tools for severe ARDS with ECMO therapy when applying to the Korean patients receiving ECMO.

Variables respiratorias asociadas a mortalidad del síndrome de distrés respiratorio agudo por influenza A (H1N1). Hospital Alberto Sabogal, Callao - Perú / Respiratory variables associated with mortality from acute respiratory distress syndrome for influenza A (H1N1). Hospital Alberto Sabogal, Callao - Peru

Determinar las variables respiratorias asociadas a mortalidad en pacientes que ingresaron a la Unidad de Cuidados Intensivos de adultos del Hospital Alberto Sabogal Sologuren, Callao-Perú, ingresados desde el 1 de julio al 31 de setiembre del 2009 con síndrome de distrés respiratorio agudo debido a infección confirmada por virus de la Influenza A (H1N1). Materiales y métodos: Se realizó un estudio de serie de casos, registrándose mediciones diarias de cada una de las variables respiratorias durante los primeros 10 días que recibieron ventilación mecánica invasiva, se estableció el promedio y desviación estándar de los grupos de pacientes sobrevivientes y no sobrevivientes, luego se buscó si esta diferencia es estadística mente significativa. Resultados: De los 10 pacientes del estudio, sobrevivieron 4; en el transcurso de los días el agravamiento de las variables que mostraron diferencia estadísticamente significativa fueron: la Presión Pico (en los días 4, 5, 6, 7, 8, 9 y 10), la Presión Plateau (en los días 4, 5, 6, 8, 9 y 10) y la Gradiente Alveolo Arterial (en los días 4, 5, 8, 9 y 10), no habiendo diferencia estadística y secuencial en las demás variables: Compliance, Pa/FiO2, pH arterial, PaO2, PaCO2, volumen tidal, volumen minuto ni con el PEEP. Conclusión: Hay diferencia significativa a partir del cuarto día y de forma secuencial en las variables Presión Pico, Presión Plateau y el Gradiente Alveolo Arterial. Recomendaciones: Al estar inmersos en una pandemia, se debe valorar la evolución de la Presión Plateau, Presión Pico y la Gradiente Alveolo Arterial para trabajar en base al pronóstico del paciente...

To determine respiratory variables mortality associated in patients admitted to the Intensive Care Unit of adult in Hospital Alberto SabogalSologuren, Callao- Peru, July 1 to September 31, 2009, with acute respiratory distress syndrome due to infection confirmed by Influenza A (H1N1). Materials and methods: A case series was performed, daily measurements were recorded for each respiratory variables during the first 10 days who receiving invasive mechanical ventilation, the mean and standard deviation of the groups of survivors and non-survivors patients was established, then sought whether this differences is statistically significant. Results: Of 10 patients studied, survived 4; during the days the worsening of variables that were statistically different were: Peak Pressure (days 4, 5, 6, 7, 8, 9 and 10), Plateau Pressure (days 4, 5, 6, 8, 9 and 10) and Alveolar Arterial Gradient (days 4, 5, 8, 9 and 10), and no statistical and sequential difference in other variables: Compliance, Pa/FiO2, arterial pH, PaO2, PaCO2, tidal volume, minute volume, or the PEEP. Conclusion: There is significant difference since the fourth day and sequentially in Peak Pressure, Plateau Pressure and Alveolar Arterial Gradient variables. Recommendations: To be immersed in a pandemic, it must assess the evolution of the Peak Pressure, Plateau Pressure, and Alveolar Arterial Gradient to work based on the patient's prognosis...

Characterization of oleic acid-induced acute respiratory distress syndrome model in rat.

Animal studies using oleic acid (OA) model to produce acute respiratory distress syndrome (ARDS) have been inconsistent. Therefore, the present study was undertaken to establish an acute model of ARDS in rats using OA and to characterize its effect on cardio-respiratory parameters and lethality. The trachea, jugular vein and femoral artery of anesthetized adult rats were cannulated. A dose of OA (30-90 µL; iv) was injected in each animal and changes in respiratory frequency (RF), heart rate (HR) and mean arterial pressure (MAP) were recorded. Minute ventilation and PaO2/FiO2 (P/F) ratio were also determined. At the end, lungs were excised for determination of pulmonary water content and histological examination. At all doses of OA, there was immediate decrease followed by increase in RF, however at 75 and 90 µL of OA, RF decreased abruptly and the animals died by 63 ± 8.2 min and 19 ± 6.3 min; respectively. In all the groups, HR and MAP changes followed the respiratory changes. The minute ventilation increased in a dose-dependent manner while the values of P/F ratio decreased correspondingly. Pulmonary edema was induced at all doses. Histological examination of the lung showed alveolar damage, microvascular congestion, microvascular injury, infiltration of inflammatory cells, pulmonary edema and necrosis in a dose-dependent manner. With these results, OA can be used to induce different grades of ARDS in rats and OA doses of 50, 60 and 75 µL resemble mild, moderate and severe forms of ARDS respectively. Hence, OA model serves as a useful tool to study the pathophysiology of ARDS.

Ventilação oscilatória de alta frequência em crianças com síndrome da angústia respiratória aguda: experiência de um centro de tratamento intensivo pediátrico / High-frequency oscillatory ventilation in children with acute respiratory distress syndrome: experience of a pediatric intensive care unit

OBJETIVO: Descrever os efeitos da aplicação da ventilação de alta frequência oscilatória como suporte ventilatório de resgate em uma série de pacientes pediátricos com síndrome da angústia respiratória aguda (SARA). MÉTODOS: Participaram do estudo 25 crianças(> 1mês e < 17 anos) internadas em uma UTI pediátrica universitária com SARA e submetidas à ventilação de alta frequência oscilatória (VAFO) por um mínimo de 48 horas, após falha da ventilação mecânica convencional. RESULTADOS: A taxa de mortalidade foi de 52% (13/25) 28 dias após o início da SARA. Ao longo de 48 horas, a aplicação da VAFO reduziu o índice de oxigenação [38 (31-50) vs. 17 (10-27)] e aumentou a relação pressão arterial parcial de O2/fração inspirada de O2 [65 (44-80) vs. 152 (106-213)]. A pressão arterial parcial de CO2 [54 (45-74) vs. 48 (39-58) mmHg] manteve-se inalterada. A pressão média de vias aéreas oscilou entre 23 e 29 cmH2O. A VAFO não comprometeu a hemodinâmica e observou-se uma redução da frequência cardíaca (141 ± 32 vs. 119 ± 22 bat/min), a pressão arterial média (66 ± 20 vs. 71 ± 17 mmHg) e o escore inotrópico [44 (17-130) vs. 20 (16-75)] mantiveram-se estáveis nesse período. Nenhum sobrevivente ficou dependente de oxigênio. CONCLUSÃO: VAFO melhora a oxigenação de pacientes pediátricos com SARA grave e hipoxemia refratária ao suporte ventilatório convencional.

OBJECTIVE: To describe the effects of high-frequency oscillatory ventilation (HFOV) as a rescue Acute respiratory distress syndrome ventilatory support in pediatric patients with acute respiratory distress syndrome (ARDS). METHODS: Twenty-five children (1 month < age < 17 years) admitted to a university hospital pediatric intensive care unit (ICU) with ARDS and submitted to HFOV for a minimum of 48 hours after failure of conventional mechanical ventilation were assessed. RESULTS: Twenty eight days after the onset of ARDS, the mortality rate was 52% (13/25). Over the course of 48 hours, the use of HFOV reduced the oxygenation index [38 (31-50) vs. 17 (10-27)] and increased the ratio of partial arterial pressure O2 and fraction of inspired O2 [65 [44-80) vs. 152 (106-213)]. Arterial CO2 partial pressure [54 (45-74) vs. 48 (39-58) mmHg] remained unchanged. The mean airway pressure ranged between 23 and 29 cmH2O. HFOV did not compromise hemodynamics, and a reduction in heart rate was observed (141±32 vs. 119±22 beats/min), whereas mean arterial pressure (66±20 vs. 71±17mmHg) and inotropic score [44 (17-130) vs. 20 (16-75)] remained stable during this period. No survivors were dependent on oxygen. CONCLUSION: HFOV improves oxygenation in pediatric patients with ARDS and severe hypoxemia refractory to conventional ventilatory support.

Ventilação oscilatória de alta frequência em crianças: uma experiência de 10 anos / High-frequency oscillatory ventilation in children: a 10-year experience

OBJETIVOS: O objetivo do estudo foi descrever a experiência com ventilação oscilatória de frequência (VOAF) em uma unidade portuguesa de Cuidados Intensivos Neonatais e Pediátricos e avaliar se a VOAF permitiu uma melhoria na oxigenação e na ventilação. MÉTODOS: Estudo de coorte retrospectivo observacional em crianças submetidas À ventilação com VOAF entre janeiro de 2002 e dezembro de 2011. Os seguintes parâmetros foram registrados: dados demográficos e clínicos; gases sanguíneos; e parâmetros ventilatórios durante as primeiras 48 horas de VOAF. RESULTADOS: O estudo incluiu 80crianças com uma idade média de 1,5 mês (mínima: uma semana; máxima: 36 meses). Pneumonia (n = 50; 62,5%) e bronquiolite (n = 18; 22,5%) foram os principais diagnósticos. Cerca de 40% (n = 32) dos pacientes desenvolveram a síndrome da angústia respiratória aguda (SARA). A ventilação mecânica convencional foi utilizada em 68 (85%) pacientes antes da VOAF. Todos os pacientes que começaram a VOAF tiveram hipoxemia, e 56 (70%) também apresentaram hipercapnia persistente. Duas horas após o início da VOAF, foi observada uma melhoria significativa na proporção SatO2/FiO2 (128 ± 0,63 em comparação a 163 ± 0,72; p < 0,001), que foi mantida durante as 24 horas de VOAF, e uma redução da FiO2. Desde o início da VOAF, a PCO2 média teve uma queda significativa (87 ± 33 em comparação a 66 ± 25; p < 0,001) e o pH aumentou significativamente (7,21 ± 0,17 em comparação a 7,32 ± 0,15; p < 0,001). A sobrevida geral foi de 83,8%. CONCLUSÕES: A VOAF permitiu uma melhoria na hipercapnia e na oxigenação. Trata-se de uma opção segura no tratamento da SARA e de doenças graves das pequenas vias aéreas.

OBJECTIVES: The aim of the study was to describe the experience with high-frequency oscillatory ventilation (HFOV) in a Portuguese Pediatric Critical Care Unit, and to evaluate whether HFOV allowed improvement in oxygenation and ventilation. METHODS: This was a retrospective observational cohort study of children ventilated by HFOV between January, 2002 and December, 2011. The following parameters were recorded: demographic and clinical data, and blood gases and ventilatory parameters during the first 48 hours of HFOV. RESULTS: 80 children were included, with a median age of 1.5 months (min: one week; max: 36 months). Pneumonia (n = 50; 62.5%) and bronchiolitis (n = 18; 22.5%) were the main diagnoses. Approximately 40% (n = 32) of the patients developed acute respiratory distress syndrome (ARDS). Conventional mechanical ventilation was used in 68 (85%) of patients prior to HFOV. All patients who started HFOV had hypoxemia, and 56 (70%) also presented persistent hypercapnia. Two hours after starting HFOV, a significant improvement in SatO2/FiO2 ratio (128 ± 0.63 vs. 163 ± 0.72; p < 0.001) that was sustained up to 24 hours of HFOV and a decrease in FiO2 were observed. Since the beginning of HFOV, the mean PCO2 significantly decreased (87 ± 33 vs. 66 ± 25; p < 0.001), and the pH significantly improved (7.21 ± 0.17 vs. 7.32 ± 0.15; p < 0.001). Overall survival was 83.8%. CONCLUSIONS:HFOV enabled an improvement in hypercapnia and oxygenation. It is a safe option for the treatment of ARDS and severe small airway diseases.

Morbilidad y mortalidad de los pacientes con síndrome de distress respiratorio agudo/injuria pulmonar aguda por Influenza A H1N1 que requirieron soporte cardiopulmonar en un hospital general / Morbidity and mortality of patients with acute respiratory distress syndrome/acute pulmonary injury due to influenza A H1N1 who required cardiopulmonary support in a general hospital

Objetivo: Determinar la morbilidad y mortalidad de los pacientes con síndrome de distress respiratorio agudo (SDRA)/injuria pulmonar aguda (IPA) por Influenza A H1N1 que requirieron soporte cardiopulmonar en un hospital general. Material y métodos: Estudio retrospectivo, descriptivo, tipo serie de casos. Se revisaron las historias clínicas, las hojas de monitoreo ventilatorio y hemodinámico de los pacientes con SDRA/IPA secundario a Influenza A H1N1 atendidos en el Servicio de Cuidados Intensivos Generales (SCIG) del Hospital Nacional Cayetano Heredia entre mayo y setiembre de 2009. El diagnóstico de Influenza A H1N1 se realizó por PCR-RT. Resultados: Se atendieron 99 pacientes con Influenza A H1N1, 9 ingresaron al SCIG por SDRA/IPA; cinco requirieron ventilación mecánica invasiva (VMI), tres ventilación mecánica no invasiva y uno no requirió soporte ventilatorio. La edad promedio fue 43,3 ± 18,3 años; el tiempo de enfermedad 8 ± 3 días. Al ingreso, el 100% tuvo fiebre y disnea, el score APACHE II fue 10,5 ± 4,1 y el SOFA 5,6 ± 3,2; el Pa02/Fi02 96,74 ± 28,6. En 4/5 pacientes en VMI el Pa02/Fi02 a las 12 h y al final de la ventilación mecánica fue < 200. La presión en cuña estimada fue 15,69 ± 3,6 y el índice cardiaco por doppler esofágico 2,4 ± 0,34. La TGO fue 160 ± 152,15, DHL 2366,33 ± 1862,13 y CPK 216 ± 298,25. Todos los pacientes recibieron Oseltamivir 150 mg cada 12 h por 10 días. Cuatro pacientes fallecieron. Conclusiones: Los pacientes con SDRA/IPA por Influenza A H1 N1, fueron adultos jóvenes, con tiempo de enfermedad prolongado; con fiebre, disnea y linfopenia; sin compromiso cardiovascular y con hipoxemia refractaria como causa de muerte.

Objective: To determine the morbidity and mortality patterns of patients with acute respiratory distress syndrome (ARDS)/acute pulmonary injury (API) due to influenza A H1N1 who required cardiopulmonary support in a general hospital. Methods: Retrospective case series. Clinical charts, mechanical ventilation and hemodynamic monitoring charts of patients with ARDS/API due to influenza A H1N1 admitted to the general intensive care unit (GICU) of Hospital Nacional Cayetano Heredia from May to September 2009 were reviewed. The diagnosis of influenza H1N1 was confirmed with RT-PCR. Results: 99 patients with influenza A H1N1 were attended; 9 were admitted in the GICU with ARDS/API; five patients required invasive mechanical ventilation (IMV); three non-invasive mechanical ventilation (NIMV) and one did not require ventilatory support. Mean age was 43.3 ± 18.3 years; mean duration of symptoms was 8 ± 3 days. On admission, 100% of patients had fever and dyspnea; mean APACHE II score was 10.5 ± 4.1 and mean SOFA score was 5.6 ± 3.2; the mean Pa02/Fi02 was 96.74 ± 28.6. In 4/5 of patients requiring IMV the Pa02/Fi02 at 12 hours and at the end of mechanical ventilation was < 200. Estimated pulmonary wedge pressure was 15.69 ± 3.6 and the cardiac index estimated by esophageal doppler ultrasound was 2.4 ± 0.34. AST was 160 ± 152.15, LDH was 2366.33 ± 1862.13 and CK was 216 ± 298.25. All patients received oseltamivir 150 mg every 12 hours per 10 days. Four patients died. Conclusions: Patients with ARDS/API due to influenza A H1N1 were young adults with protracted disease with fever and lymphopenia, without cardiovascular involvement and with refractory hypoxemia as the main cause of death.

High-frequency oscillatory ventilation for acute respiratory distress syndrome.

Objective. To evaluate the effectiveness of HFOV in pediatric patients with acute respiratory distress syndrome. Methods. In this retrospective study, we reviewed all 20 pediatric patients, who were consecutively ventilated with HFOV in the pediatric intensive care unit of a tertiary medical center, from January 2006 to February 2007. Results. A total of 20 patients were enrolled. The median age of the subjects was 70 (3-168) months; 10 were male. All patients received conventional ventilation before HFOV. After initiation of HFOV, there was an immediate and sustained increase in PaO2/FiO2 ratio. The PaO2/FiO2 ratio was elevated and OI was decreased significantly after 10-20 minutes and maintained for at least 48 hours (p= 0.03, both). Thirteen of the 20 patients were successfully weaned. No significant change in the mean arterial pressure and heart rate was noted after HFOV. Overall survival rate was 65%. Of 20 patients, 11 patients suffered from extrapulmonary ARDS (ARDSexp) and 9 from pulmonary ARDS (ARDSp). When HFOV was initiated, there was significant increase in PaO2/FiO2 and decrease in OI in ARDSexp compared to ARDSp (p= 0.03, both). Also mortality rate was significantly lower in patients with ARDSexp (9% vs.66%), (p= 0.01). Conclusion. In our study, HFOV was effective in oxygenation and seems to be safe for pediatric ARDS patients. HFOV affected ARDSp and ARDSexp paediatric patients differently. However prospective, randomized controlled trials are needed to identify its benefits over conventional modes of mechanical ventilation.

The Clinical Efficacy of GOCA Scoring System in Patients with Acute Respiratory Distress Syndrome

To explore the following hypotheses: 1) Gas exchange, Organ failure, Cause, Associated disease (GOCA) score, which reflects both general health and the severity of lung injury, would be a better mortality predictor of acute respiratory distress syndrome (ARDS) than acute physiology and chronic health evaluation (APACHE II) or simplified acute physiology score (SAPS II), which are not specific to lung injury, and lung injury score (LIS) that focuses on the lung injury; 2) the performance of APACHE II and SAPS II will be improved when reinforced by LIS, we retrospectively analyzed ARDS patients (N=158) admitted to a medical intensive care unit for five years. The overall mortality of the ARDS patients was 53.2%. Calibrations for all models were good. The area under the curve of (AUC) of LIS (0.622) was significantly less than those of APACHE II (0.743) and SAPS II (0.753). The AUC of GOCA (0.703) was not better than those of APACHE II and SAPS II. The AUCs of APACHE II and SAPS II tended to further increase when reinforced by LIS. In conclusion, GOCA was not superior to APACHE II or SAPS II. The performance of the APACHE II or SAPS II tended to improve when combining a general scoring system with a scoring system that focused on the severity of lung injury.

Precisão do diagnóstico clínico da síndrome do desconforto respiratório agudo quando comparado a achados de necropsia / Accuracy of clinical diagnosis of acute respiratory distress syndrome in comparison with autopsy findings

OBJETIVO: Comparar a definição de síndrome do desconforto respiratório agudo (SDRA) estabelecida pela American-European Consensus Conference (AECC, Conferência Americano-Européia) com achados de necropsia. MÉTODOS: Avaliaram-se todos os pacientes que morreram na unidade de terapia intensiva do Hospital Universitário da Universidade Federal de Juiz de Fora entre 1995 e 2003 e que foram submetidos à necropsia. Seus prontuários foram revisados para estabelecer a presença ou não dos critérios clínicos de SDRA, cujo diagnóstico histológico foi definido pela presença de dano alveolar difuso (DAD). RESULTADOS: No período, 592 pacientes faleceram e 22 foram submetidos à necropsia. Destes, 10 pacientes (45 por cento) preencheram os critérios de SDRA pela AECC e sete (32 por cento) preencheram os critérios histopatológicos de DAD. A sensibilidade da definição clínica foi de 71 por cento (IC95 por cento: 36-92 por cento) e a especificidade foi de 67 por cento (IC95 por cento: 42-85 por cento). Os valores preditivos positivo e negativo foram, respectivamente, 50 e 83 por cento; e as razões de verossimilhança positiva e negativa foram, respectivamente, 2,33 e 0,47. Os achados histopatológicos nos cinco pacientes que preencheram os critérios clínicos de SDRA, mas não apresentavam DAD, foram pneumonia (n = 2), embolia pulmonar (n = 1), tuberculose (n = 1) e criptococose (n = 1). CONCLUSÃO: A precisão dos critérios da AECC para diagnóstico de SDRA não é tão boa. Em função do baixo valor preditivo positivo e da baixa razão de verossimilhança positiva do diagnóstico clínico, outras hipóteses devem ser consideradas quando há suspeita de SDRA.

OBJECTIVE: To compare the American-European Consensus Conference (AECC) definition of acute respiratory distress syndrome (ARDS) to autopsy findings. METHODS: All patients who died in the intensive care unit of the Federal University of Juiz de Fora University Hospital between 1995 and 2003 and were submitted to autopsy were included in the study. Patient clinical charts were reviewed to establish whether cases met the AECC criteria for a diagnosis of ARDS, histologically defined as the presence of diffuse alveolar damage (DAD). RESULTS: During the study period, 592 patients died, and 22 were submitted to autopsy. Of those 22 patients, 10 (45 percent) met the AECC criteria, and 7 (32 percent) met the histopathological criteria for DAD. The AECC clinical criteria presented a sensitivity of 71 percent (95 percentCI: 36-92 percent) and a specificity of 67 percent (95 percentCI: 42-85 percent). The positive and negative predictive values were, respectively, 50 and 83 percent, whereas the positive and negative likelihood ratios were, respectively, 2.33 and 0.47. The histopathological findings in the 5 patients who met AECC criteria but did not present DAD were pneumonia (n = 2), pulmonary embolism (n = 1), tuberculosis (n = 1), and cryptococcosis (n = 1). CONCLUSION: The accuracy of the AECC definition of ARDS was godless than satisfactory. Due to the low positive predictive value and the low positive likelihood ratio, other hypotheses must be considered when ARDS is suspected.

Ventilação de alta freqüência em crianças e adolescentes com síndrome do desconforto respiratório agudo (impacto sobre o uso de ecmo) / High-frequency ventilation in children and adolescents with acute respiratory distress syndrome (impact on the use of ecmo)

OBJETIVO: Avaliar o efeito da ventilação de alta freqüência (VAF) em crianças e adolescentes com síndrome do desconforto respiratório (SDRA) por meio de estimativas de sobrevida e tempo de ventilação. Verificar se a VAF reduziu a indicação de oxigenação de membrana extracorpórea (ECMO) em crianças e adolescentes com SDRA. MÉTODOS: A técnica empregada foi uma revisão sistemática da literatura médica sobre o uso de VAF e ECMO em crianças e adolescentes com SDRA. O levantamento bibliográfico utilizou os bancos de dados Medline, Lilacs e Embase. Os termos utilizados para pesquisa foram: adult respiratory distress syndrome, ARDS, acute respiratory distress syndrome, respiratory distress syndrome, extracorporeal membrane oxygenation, ECMO, high-frequency ventilation, high-frequency jet ventilation e high-frequency oscillatory ventilation. Foram procurados ensaios clínicos controlados e randomizados, estudos de coorte e série de casos que comparavam VAF com ventilação mecânica convencional (VMC), ECMO com VMC ou VAF precedendo o uso de ECMO. RESULTADOS: Foram identificadas 289 publicações relacionadas a VAF, SDRA e ECMO. Destas, apenas nove atendiam aos critérios de seleção pré-estabelecidos referindo-se a utilização de VAF e/ou ECMO em crianças e adolescentes com SDRA. CONCLUSÃO: Não foi possível confirmar se o uso de VAF melhora a sobrevida de crianças e adolescentes com SDRA. Quanto ao tempo de ventilação, não houve estudo que comprovasse, com significância estatística, a sua redução ou aumento. Não foi possível verificar se VAF diminui ou não a indicação de ECMO em crianças e adolescentes com SDRA.

OBJECTIVE: To assess the effect of high-frequency ventilation (HFV) in children and adolescents with acute respiratory distress syndrome (ARDS) through estimates of survival rate and time of ventilation. To verify whether HFV can reduce the indication for extracorporeal membrane oxygenation (ECMO) in children and adolescents with ARDS. METHODS: a systematic review of medical literature on the use of HFV and ECMO in children and adolescents with ARDS was carried out. Medline, Lilacs and Embase databases were searched for the following terms: adult respiratory distress syndrome, ARDS, acute respiratory distress syndrome, respiratory distress syndrome, extracorporeal membrane oxygenation, ECMO, high-frequency ventilation, high-frequency jet ventilation and high-frequency oscillatory ventilation. Search was conducted for controlled and randomized clinical trials, cohort studies and a series of cases which compared HFV with conventional mechanic ventilation (CMV), ECMO with CMV, or HFV preceding the use of ECMO. RESULTS: Two hundred eighty nine publications related to HFV, ARDS and ECMO were found. Of these, only nine matched pre-established selection criteria which refer to use of HFV and/or ECMO in children and adolescents with ARDS. CONCLUSION: It was not possible to determine if use of HFV improves the survical rate of children and adolescent with ARDS. Regarding ventilation time, there is no study that confirms, with statistical significance, its increase or decrease. Whether HFV reduces or not indication of ECMO for children and adolescents with ARDS was also determined.

Ventilación de alta frecuencia oscilatoria en el rescate de hipoxemia catastrófica en niños con síndrome de distrés respiratorio agudo / High frequency oscillatory ventilation on catastrophic hypoxemia childs with acute respiratory distress syndrome

Introducción: La ventilación de alta frecuencia oscilatoria (VAFO) es una modalidad empleada en pacientes con Síndrome de Distress Respiratorio Agudo (SDRA) refractario a ventilación mecánica convencional (VMC). El rol de esta terapia frente a hipoxemia catastrófica, con índice de oxigenación (IO >= 40), no está definido en la actualidad, por corresponder a pacientes habitualmente subsidiarios de soporte extracorpóreo. Objetivo: Presentar el efecto de la VAFO en SDRA grave con hipoxemia extrema, refractaria a terapia convencional máxima. Diseño y pacientes: Se empleó el ventilador Sensor Medics 3100A según protocolo preestablecido. Describimos la totalidad de los pacientes con insuficiencia respiratoria que ingresaron entre 1999 y 2005 en nuestra unidad que tras terapia ventilatoria convencional permanecieron con índice de oxigenación mayor que 40. Se registró intercambio gaseoso antes, durante las primeras 48 h y previo al retorno a VMC. Describimos permanencia en VAFO, complicaciones y mortalidad en este grupo. Mediciones y resultados: Se ventilaron 12 pacientes con una mediana de edad de 3,5 meses; score de lesión pulmonar de 3,5 (3,25-4). Previo al inicio de la VAFO, la PaO2/FIO2 y el IO fueron de 39 y 47 respectivamente. La duración de la VMC previa fue de 65 h. Esta terapia logró una rápida y progresiva mejoría de la oxigenación, máxima a las 24 h de iniciada (PaO2/FIO2=137 e IO=18, p<0,01). La supervivencia a los 28 días fue de 75 por ciento. Conclusión: Una elevada supervivencia asociado a la mejoría en la oxigenación puede ser obtenida en pacientes con hipoxemia extrema empleando la VAFO, por lo que se constituye en opción terapéutica a considerar en este subgrupo.

Introduction: High frequency oscillatory ventilation (HFOV) is a ventilatory modality which has demonstrated to be useful in patients with Acute Respiratory Distress Syndrome (ARDS) refractory to conventional mechanical ventilation (CMV). The role of this therapy on catastrophic hypoxemia (oxygenation index [OI] over 40) is not clearly defined yet since these patients are suitable for extracorporeal support therapy nowadays. Objective: To report the effect of HFOV in severe ARDS refractory to maximal CMV therapy. Design and patients: A Sensor Medics 3100A ventilator was used. We considered all the patients who were admitted between 1999 and 2005 for acute respiratory failure who remained with OI over 40 despite maximal CMV. The record included arterial blood gases immediately before and during the first 48 hours of HFOV, and prior to the switch onto CMV. We analyzed the duration on HFOV, the presence of complications and the mortality rate of the group. Measurements and results: Twelve patients were enrolled with a median age of 3.5 months, and lung injury score of 3.5 (range: 3.25 to 4). Prior to HFOV the median PaO2/FIO2 ratio and OI were 39 and 47, respectively. The previous CMV duration was 65 hours. The therapy was extremely useful in improving the oxygenation obtaining the maximal effect at the 24 hours of therapy (PaO2/FIO2 ratio= 137 e IO=18, p<0.01). The survival rate was 75 percent on day 28. Conclusions: A reasonably high survival rate associated with an improvement of the oxygenation is achieved in patients with extreme hypoxemia using HFOV. Thus, this therapy should be considered in this group.

Incidência de lesão pulmonar aguda e síndrome da angústia respiratória aguda no centro de tratamento intensivo de um hospital universitário: um estudo prospectivo / Incidence of acute lung injury and acute respiratory distress syndrome in the intensive care unit of a university hospital: a prospective study

OBJETIVO: Estabelecer a incidência de lesão pulmonar aguda e síndrome da angústia respiratória aguda, os principais fatores de risco associados e a mortalidade em um centro de tratamento intensivo. Comparar os pacientes que desenvolveram lesão pulmonar com pacientes com fatores de risco, porém sem lesão pulmonar aguda e síndrome da angústia respiratória aguda. MÉTODOS: O estudo foi realizado no centro de tratamento intensivo da Unidade de Emergência do Hospital das Clínicas de Ribeirão Preto. Os pacientes admitidos no período de maio de 2001 a abril de 2002 foram acompanhados prospectivamente. Foram registrados: características clínicas, índice Acute Physiologic and Chronic Health Evaluation II, complicações, tempo de internação no centro de tratamento intensivo e no hospital, e dados sobre a lesão pulmonar. RESULTADOS: ocorreram 524 admissões no período, 175 pacientes apresentaram fatores de risco para lesão pulmonar aguda e síndrome da angústia respiratória aguda (33,4%), 33 desenvolveram síndrome da angústia respiratória aguda (6,3%) e 12 desenvolveram lesão pulmonar aguda (2,3%). Os principais fatores de risco foram pneumonia (37,7%), choque (32,0%), politrauma (24,6%) e sepse (21,1%). Os pacientes que desenvolveram lesão pulmonar aguda tiveram maior índice Acute Physiologic and Chronic Health Evaluation II (p < 0.05), maior freqüência de sepse (p = 0.001), mais complicações (p = 0.001), maior mortalidade (p = 0.001). A principal causa de morte foi a Síndrome de Disfunção de Múltiplos Órgãos e Sistemas (38,5%). CONCLUSÃO: A incidência de LPA e SARA foi de 2,3 e 6,3% respectivamente. Os principais fatores derisco foram pneumonia, choque, politrauma e sepse. Os pacientes com LPA e SARA apresentaram-se mais graves e tiveram alta mortalidade.

Síndrome Hellp no asociado a hipertensión arterial: a propósito de un caso en el Hospital Patrocinio Peñuela Ruíz / Syndrome hellpp not associated to arterial hypertension: concerning a case in the Hospital Patrocinio Peñuela Ruíz

El síndrome HELLP se presenta usualmente en pacientes con preclampsia; sin embargo, puede presentarse en ausencia de hipertensión arterial en el 20 por ciento de los casos. Se presenta caso de primigesta de 34 años, 35 semanas de gestación sin antecedentes importantes y control prenatal normal, quien acusa epigastralgia de aparición súbita, encontrándose cifras tensionales de 120/70 mmHG. Presenta cuadro convulsivo seguido de hipertensión arterial transitoria; se realiza cesárea segmentaria con post-operatorio inmediato en malas condiciones generales y cifras tensionales normales. Hallazgos de laboratorio que orientan hacia Síndrome HELLP clase 2 con insuficiencia renal aguda. En Unidad de Cuidados Intensivos desarrolla Síndrome de Dificultad Respiratoria del Adulto. Finalmente cae en asistolia, y la paciente fallece. En este caso, el Síndrome HELLP se presenta con sintomatología de pocas horas de evolución lo cual no es común encontrar. Destacamos el hecho que la hipertensión no fue un evento significativo. En la literatura investigada no encontramos casos similares reportados en el país.

Sindrome de distres respiratorio agudo utilidad de los costicoides / Acute respiratory distress syndrome: role of steroids

En Argentina, el síndrome de distrés respiratorio agudo (SDRA) representa el 7.7% de las admisiones en terapia intensiva y está asociado con una alta morbilidad y mortalidad (58%). Con frecuencia la muerte puede ser atribuida a más de una causa. La hipoxemia refractaria es una causa de muerte poco frecuente (15%) y en muchos casos puede coexistir con disfunción multiorgánica, sepsis o shock séptico. La utilidad de los esteroides como parte del tratamiento es aún motivo de debate a pesar de las múltiples series de casos y estudios clínicos publicados. En el artículo se evalúa la utilidad de los esteroides en el SDRA a través de la revisión de la bibliografía disponible. Se concluye que los esteroides estarían indicados en un pequeño subgrupo de pacientes con SDRA no resuelto o tardío, después de descartar o controlar una infección activa.

Factors effecting the outcome of acute respiratory distress syndrome in pediatric patients treated with high frequency oscillatory ventilation.

OBJECTIVES: To evaluate the survival rate and factors affecting the outcome of pediatric patients treated with high-frequency oscillatory ventilation (HFOV) for diffuse alveolar disease (DAD) compatible with acute respiratory distress syndrome (ARDS). METHOD: A cohort study was conducted at the pediatric intensive care unit of Queen Siritkit National Institute of Child Health from 1st January 1999 to 31st December 2001. Children who suffered from DAD compatible with ARDS were enrolled. Inclusion criteria were PaO2/FiO2 < 200 and oxygenation index (OI) > 10. High-frequency oscillatory ventilator (3100A Sensor Medics Corp, Yorba Linda, Calif) was used applying high volume strategy of treatment. Patients were weaned to conventional ventilation (CV) once clinical improvement occurred. Demographic data, duration of CV mode before changing to HFOV, duration of HFOV, ventilator parameters and gas exchange variables from beginning and during the course of HFOV were recorded, so patient data could be compared between surviving and non-surviving groups. RESULTS: A total of 21 children were enrolled during the 3 year period. There were 4 patients with simultaneous air leak syndrome and a total of 10 male patients. The average age was 3.58 +/- 3.9 years. There were 11 surviving patients (52.4%). Data of ventilator parameters and gas exchange variables after changing to HFOV for 4-6 hours for the two groups, FiO2 was higher (0.99 +/- 0.32 vs 0.84 +/- 0.18; p = 0.02) and alveolar arterial oxygen gradient [P(A-a)O2] was lower (448.5 +/- 140.8 vs 562.7 +/- 99.9 mmHg; p = 0.047) in the surviving group than in the non-surviving group. Concerning mean airway pressure (Paw), oxygenation index (OI), P(A-a)O2 and PaO2/FiO2 at initiation and during the course of HFOV with comparison of the surviving and non-surviving groups: Paw and OI decreased in the surviving group and was significantly different at 36 and 24 hours respectively. P(A-a)O2 was statistically significantly lower at 6 hours after HFOV initiation in the surviving group. PaO2/FiO2 was statistically significantly increased at 24 hours in the surviving group. CONCLUSION: Implement of HFOV is useful in patients with DAD, ARDS and air leak syndrome from the initial phase of illness which fulfill criteria for decreasing ventilator induced lung injury and thus decrease the mortality rate from ARDS. Predisposing survival factor showing statistically significant differences was lower Paw during CV before changing to HFOV, lower Paw at 36 hours, lower OI at 24 hours, lower P(A-a)O2 at 6 hours and higher PaO2/FiO2 at 24 hours. These parameters are good indicators for the prognosis of ARDS for patients responding or not responding to HFOV.

Síndrome de distrés respiratorio agudo e injuria pulmonar aguda: epidemiología / Acute respiratory distress syndrome and acute lung injury: epidemiology

La lesión pulmonar aguda (LPA) y el síndrome de distrés respiratorio agudo (SDRA) son entidades frecuentes y graves que insumen gran parte de nuestros recursos. Este estudio descriptivo-prospectivo pretende estimar la incidencia y mortalidad de ambos síndromes y conocer la epidemiología del SDRA, tratando de establecer factores de riesgo asociados a mayor mortalidad. Ingresaron al estudio los pacientes que cumplieron los criterios diagnósticos establecidos en el Consenso Americano - Europeo de 1992. Se recolectaron datos en el período enero 2000 - mayo 2001, incluyéndose: edad, sexo, estadía, enfermedad motivo del ingreso, puntaje APACHE II, causa del SDRA, días de ventilación mecánica, modo ventilatorio, puntaje de Murray, neumonía asociada al ventilador (NAV), disfunción orgánica múltiple (DOM) asociada, mortalidad y causa directa de muerte. Se registraron 108 pacientes con los criterios antedichos. La edad promedio fue de 58ñ16,36 años, 60 por ciento sexo masculino, APA CHE II promedio de 15ñ5,2 y estadía promedio de 13ñ11 días. La mortalidad global fue de 53,7 por ciento. Del total, 81 presentaron SDRA y 27 LPA. La incidencia anual para el SDRA fue 51,2 por 100.000 habitantes por año. Aquellos pacientes con distrés fueron 7 por ciento del total de ingresos y 20 por ciento de los ventilados. La causa más común fue la infecciosa. Su mortalidad llegó a 61,7 por ciento, siendo las causas más frecuentes de muerte el shock, la DOM y la hipoxemia. La mortalidad de los traumatizados fue menor que la de los pacientes con patología médica (p<0,0007). La neumonía asociada al ventilador como complicación no aumentó la mortalidad de los pacientes con SDRA y los factores asociados a mayor mortalidad fueron: el número de disfunciones orgánicas extramulmonares asociadas, la estadía y el motivo de ingreso