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.

Cautious Use of Veno-Arterial Extracorporeal Membrane Oxygenation for MRSA Sepsis and Acute Respiratory Distress Syndrome.

Extracorporeal membrane oxygenation (ECMO) for septic shock has been reported occasionally and it has been shown to have reasonable outcomes in pediatrics cases. However, the adult ECMO for septic shock is not as clearly elucidated. Here we present a case of adult ECMO for septic shock secondary to MRSA, complicated by multi-organ abscesses. This case illustrates that MRSA sepsis is a major contraindication for the use of ECMO.

Pulmonary hypertension due to acute respiratory distress syndrome

Our aims were to describe the prevalence of pulmonary hypertension in patients with acute respiratory distress syndrome (ARDS), to characterize their hemodynamic cardiopulmonary profiles, and to correlate these parameters with outcome. All consecutive patients over 16 years of age who were in the intensive care unit with a diagnosis of ARDS and an in situ pulmonary artery catheter for hemodynamic monitoring were studied. Pulmonary hypertension was diagnosed when the mean pulmonary artery pressure was >25 mmHg at rest with a pulmonary artery occlusion pressure or left atrial pressure <15 mmHg. During the study period, 30 of 402 critically ill patients (7.46%) who were admitted to the ICU fulfilled the criteria for ARDS. Of the 30 patients with ARDS, 14 met the criteria for pulmonary hypertension, a prevalence of 46.6% (95% CI; 28-66%). The most common cause of ARDS was pneumonia (56.3%). The overall mortality was 36.6% and was similar in patients with and without pulmonary hypertension. Differences in patients' hemodynamic profiles were influenced by the presence of pulmonary hypertension. The levels of positive end-expiratory pressure and peak pressure were higher in patients with pulmonary hypertension, and the PaCO2 was higher in those who died. The level of airway pressure seemed to influence the onset of pulmonary hypertension. Survival was determined by the severity of organ failure at admission to the intensive care unit.

Application of Damage Control Resuscitation Strategies to Patients with Severe Traumatic Hemorrhage: Review of Plasma to Packed Red Blood Cell Ratios at a Single Institution

When treating trauma patients with severe hemorrhage, massive transfusions are often needed. Damage control resuscitation strategies can be used for such patients, but an adequate fresh frozen plasma: packed red blood cell (FFP:PRBC) administration ratio must be established. We retrospectively reviewed the medical records of 100 trauma patients treated with massive transfusions from March 2010 to October 2012. We divided the patients into 2 groups according to the FFP:PRBC ratio: a high-ratio (> or =0.5) and a low-ratio group (<0.5). The patient demographics, fluid and transfusion quantities, laboratory values, complications, and outcomes were analyzed and compared. There were 68 patients in the high-ratio and 32 in the low-ratio group. There were statistically significant differences between groups in the quantities of FFP, FFP:PRBC, platelets, and crystalloids administered, as well as the initial diastolic blood pressure. Bloodstream infections were noted only in the high-ratio group, and the difference was statistically significant (P=0.028). Kaplan-Meier plots revealed that the 24-hr survival rate was significantly higher in the high-ratio group (71.9% vs. 97.1%, P<0.001). In severe hemorrhagic trauma, raising the FFP:PRBC ratio to 0.5 or higher may increase the chances of survival. Efforts to minimize bloodstream infections during the resuscitation must be increased.

Influenza A (H1N1) was not associated with obesity in pregnant women living in Toluca, México / La Influenza A (H1N1) no se asoció con la obesidad en mujeres embarazadas en Toluca, México

Objective The aim was to verify whether being overweight could have played a critical role in cases of mortality caused byinfluenza A (H1N1) in pregnant women. This virus' prevalence was also analyzed among people suffering from acute respiratory disease being attended at the state of Mexico's Autonomous University's medical research centre. Methods The clinical files of women having influenza A (H1N1) attending the Monica Pretelini maternal-perinatal hospital's (HMPMP) intensive care unit in Toluca, Mexico, were reviewed. According to international recommendations, clinical detection of possible new cases of this disease was kept an open as a second step. Results Five women suffering influenza A (H1N1) was attended at HMPMP's intensive care unit during 2009; only one survived. No differences in body mass index were found when comparing the anthropometric characteristics to another group of women affected by acute respiratory diseases; in fact, this parameter was below the limits for being overweight in both cases. No new case of influenza A (H1N1) was found after the first eight months of 2010. Discussion It could not be verified whether being overweight was a factor of higher mortality due to influenza A (H1N1) amongst pregnant women in the state of Mexico. The key to better survival for pregnant women hospitalized with influenza A (H1N1) seemed to be early treatment with oseltamivir. The cases decreased dramatically after the severe wave of the new pandemic due to unknown reasons.

Objetivo Nuestro objetivo fue verificar si en los casos de mortalidad por influenza A (H1N1) en mujeres embarazadas, el sobrepeso tuvo un papel fundamental. También hemos analizado la prevalencia de este virus entre personas con enfermedad respiratoria aguda atendidas en el Centro de Investigación en Ciencias Médicas de la Universidad Autónoma del Estado de México. Métodos Se revisaron los expedientes clínicos de las mujeres con influenza A (H1N1) atendidos en la Unidad de Cuidados Intensivos Obstétricos del Hospital Materno Perinatal, Toluca, México. De acuerdo con las recomendaciones internacionales, como segunda etapa se mantuvo un programa de detección de este virus en la población general. Resultados Hubo cinco embarazadas con influenza A (H1N1), durante el año 2009, de las cuales sólo una sobrevivió. Al comparar las características antropométricas con otro grupo de mujeres afectadas por enfermedades respiratorias agudas no encontramos diferencias en el índice de masa corporal. De hecho, en ambos casos, este parámetro fue inferior a los límites de sobrepeso. Después de los primeros ocho meses del año 2010 no se encontraron nuevos casos de influenza A (H1N1). Discusión No hemos podido verificar que el sobrepeso sea un factor de mayor mortalidad en casos de infección por influenza A (H1N1) entre las mujeres embarazadas del Estado de México. La clave para una mejor supervivencia en mujeres embarazadas hospitalizadas con influenza A (H1N1) parece ser el tratamiento precoz con Oseltamivir. Por razones desconocidas después de la ola severa de la nueva pandemia los casos disminuyeron.

Fatores de risco na síndrome do desconforto respiratório agudo / Risk factors for acute respiratory distress syndrome

A síndrome do desconforto respiratório agudo (SDRA) é uma condição crítica que consiste de insuficiência respiratória hipoxêmica aguda grave, com infiltrados pulmonares bilaterais que não são atribuídos a hipertensão atrial esquerda. Trata-se de uma desordem heterogênea que pode ser desencadeada por variadas etiologias. Um melhor conhecimento de seus fatores de risco pode ajudar no seu diagnóstico precoce. Os fatores de risco para SDRA têm permanecido os mesmos por vários anos e incluem pneumonia, sepse, aspiração de conteúdo gástrico, trauma grave e múltiplas transfusões, dentre outros. Essas condições clínicas podem ser divididas entre aquelas associadas à lesão direta dos pulmões (fatores pulmonares) e àquelas que causam lesão indireta, no contexto de um processo sistêmico (fatores extrapulmonares). Enquanto alguns autores argumentam que esses fatores resultam em apresentações diferentes, as implicações clínicas dessa classificação não foram bem estabelecidas. Outras condições podem aumentar a suscetibilidade para SDRA, como abuso de álcool, obesidade e ventilação mecânica com altos volumes correntes e altas pressões de vias aéreas; por outro lado, diabetes parece reduzir o risco de desenvolvimento de SDRA. Nos últimos anos, especial interesse tem surgido em estudos sobre predisposição genética à SDRA, e, no futuro, eles poderão ajudar na compreensão do motivo pelo qual apenas alguns pacientes com estímulo patológico desenvolvem a síndrome.

Acute respiratory distress syndrome (ARDS) results in critical illness consisting of acute severe hypoxemic respiratory failure with bilateral pulmonary infiltrates that are not attributable to left atrial hypertension. It is a heterogeneous disorder that can be triggered by myriad etiologies. Greater knowledge of the risk factors involved could increase the rate of early ARDS diagnosis. The risk factors for ARDS, which have remained the same for several years, include pneumonia, sepsis, aspiration of gastric contents, severe trauma, and multiple transfusions. These can be divided into those associated with direct injury to the lung (pulmonary factors) and those that cause indirect lung injury in the setting of a systemic process (extrapulmonary factors). Although some authors argue that the various risk factors provoke different presentations, the clinical implications have not been clarified. Other conditions that can increase susceptibility to ARDS include alcohol abuse, obesity, and mechanical ventilation with high tidal volume and high airway pressure. However, diabetes seems to reduce the risk of developing ARDS. In recent years, there has been increased interest in the study of genetic predisposition to ARDS, which might eventually prove helpful in explaining why only some patients with pathologic stimuli develop the syndrome.

Diagnóstico da síndrome do desconforto respiratório agudo na criança / Diagnosis of pediatric acute respiratory distress syndrome

Este estudo faz uma revisão crítica da definição da Conferência Americana e Europeia de Consenso em lesão pulmonar aguda (LPA) e síndrome do desconforto respiratório agudo (SDRA), procurando responder as seguintes questões: 1) é superior a outras definições existentes?; 2) identifica um grupo de pacientes com os mesmos mecanismos fisiopatológicos?; 3) tem valor prognóstico?; 4) identifica um grupo de pacientes que pode se beneficiar das mesmas estratégias terapêuticas?; e 5) pode ser extrapolada adequadamente para a faixa etária pediátrica? Os autores buscam também soluções para contornar as limitações da definição de hipoxemia na faixa etária pediátrica e apresentam que a maneira mais simples e homogênea de se diagnosticar hipoxemia precocemente na criança é a medida não invasiva da SpO2 em ar ambiente. Por fim, são apresentadas duas propostas de definição da LPA/SDRA na criança: uma mais abrangente, para diagnóstico precoce e aplicação em estudos de triagem sobre abordagem preventiva, e outra mais restrita, para utilização em crianças submetidas à ventilação mecânica, em estudos explanatórios de eficácia terapêutica.

This study critically evaluates the American-European Consensus Conference definition of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) and attempts to answer the following questions: 1) Is it better than other definitions?; 2) Does it identify a group of patients with the same pathophysiological mechanisms?; 3) Does it have prognostic value?; 4) Does it distinguish a group of patients that will benefit from the same therapeutic strategies?; and 5) Can it be effectively extrapolated to children? Alternatives to the invasive procedures employed in order to identify hypoxemia are also discussed. The authors presented a simple way to diagnose early hypoxemia in children based on SpO2. Finally, two definitions of pediatric ALI/ARDS are proposed: a broader and more sensitive definition, to be used in screening for early ALI and in pragmatic trials; and a more restrictive and specific definition, to be used in mechanically ventilated children evaluated in explanatory trials for therapeutic intervention purposes.

Poluição atmosférica e internações por insuficiência cardíaca congestiva em adultos e idosos em Santo André (SP) / Air pollution and hospital admissions of adults and elderly due to congestive heart failure in Santo André (SP), Brazil

Introdução: A poluição atmosférica urbana produz efeitos adversos sobre a saúde dos grupos mais suscetíveis. Objetivo: Avaliar os efeitos da exposição à poluição do ar sobre as internações hospitalares por insuficiência cardíaca congestiva de adultos e idosos residentes na cidade de Santo André. Métodos: Foram obtidas as internações por insuficiência cardíaca congestiva (ICC) de adultos e idosos (35 anos ou mais) em todos os hospitais conveniados ao Sistema Unico de Saúde, na cidade de Santo André, para o período entre 2000 a 2007. Os níveis de PM10, temperatura e umidade foram fornecidos pela CETESB. Foi utilizado modelo linear generalizado de regressão de Poisson e um modelo de defasagem de até 20 dias com distribuição polinomial de sexto grau para estimar os efeitos do poluente no desfecho, controlando-se para sazonalidades de longa e curta duração, feriados e fatores meteorológicos. Resultados: A média do PM10 durante o período do estudo esteve abaixo do padrão de qualidade do ar adotado pela CETESB, que é de 50 ?g/m3, e o valor máximo diário observado também não ultrapassou o limite de 150 ?g/m3. Para um aumento de 24,6 ?g/m3 de PM10, foi observado um aumento de 3,0% (IC95%: 0,3-5,7) nas internações por insuficiência cardíaca congestiva no mesmo dia da exposição. O efeito do poluente sobre o desfecho apresentou comportamento bifásico, constatando-se novo aumento nas internações 10 a 12 dias após a exposição. Conclusões: Aumentos na concentração de PM10 na cidade de Santo André estão associados a aumentos nas internações por ICC entre os adultos e idosos.

Introduction: Urban atmospheric pollution causes adverse health effects on most susceptible groups. Objective: To evaluate the effects of exposure to air pollution on hospital admissions due to congestive heart failure in adults and elderly residents in the city of Santo André, SP, Brazil. Methods: We obtained data on hospitalizations for congestive heart failure (CHF) of adults and the elderly (older than 35 years of age) in all hospitals under the National Health System in the city of Santo André for the period from 2000 to 2007. Levels of PM10, temperature and humidity were provided by CETESB. We used generalized linear Poisson regression model and a sixtieth-degree polynomial distributed lag model with length up to 20 days to estimate pollutant effect on the outcome, controlling for seasonality, weather variables and short-term trend. Results: The average of PM10 during the studied period was below the air quality standard adopted by CETESB, which is 50 mg/m3. Also, PM10 daily records did not surpassed the standard of 150 mg/m3. An increase of 24.6 mg/m3 in PM10 was associated with an increase of 3.0% (95%CI: 0,3-5,7) in hospitalizations for congestive heart failure in the same day of exposure. The pollutant?s effect in the outcome presented a biphasic behavior, with another increase of the outcome 10 to 12 days after exposure. Conclusions: Increases in PM10 in the city of Santo André are associated with increases in the number of hospitalizations for CHF among adults and the elderly.

Pediatric hospitalizations associated with 2009 pandemic influenza A (H1N1): An experience from a tertiary care center in north India.

Objectives To describe our experience in children hospitalized with the pandemic Influenza A (H1N1) from Northern India. Methods The retrospective case study was conducted at the Pediatric ward and Pediatric Intensive Care Unit (PICU) dedicated to the children (aged 18 years or younger) with influenza-like illness (ILI) with positive laboratory test results for pandemic H1N1 by reverse-transcriptase polymerasechain- reaction assay. Results Between August 2009 and January 2010, a total of 100 children were hospitalized with suspected 2009 H1N1 influenza with Category “C” as described by the Government of India. Twenty five patients were positive for H1N1 and 9 for seasonal influenza A. The most common presentation (H1N1 positive) was with fever (100%), cough (100%), coryza (52%), respiratory distress (88%), vomiting (28%) and diarrhea (16%). One child presented with hypernatremic dehydration and seizures (Serum sodium 174 meq/l). Of the H1N1 positive hospitalized children, 7 (28%) had respiratory failure and required PICU admission, 4 (16%) required mechanical ventilation, and 3 (12%) died. The major radiological findings were bilateral pulmonary infiltrates and consolidation. All patients were treated with oral Oseltamivir suspension or capsule as per appropriate weigh band and supportive care as required. Two deaths were caused by refractory hypoxemia and one by refractory shock. Conclusions The exact incidence of Pandemic 2009 H1N1 influenza on morbidity and mortality is difficult to calculate since only Category “C” patients were screened.

Acute respiratory distress syndrome in pediatric intensive care unit.

Objective. To report causes, clinical feature and outcome of children with Acute Respiratory Distress Syndrome (ARDS). Methods. The case records of children admitted with ARDS from June 2003 to June 2006 were retrospectively reviewed and the data collected was analyzed. Results. A total of 17 children were diagnosed as ARDS during study period giving an incidence of 22.7/1,000 admissions. The mean (SD) age was 74.5 (56.32) mo [range 6 -144 mo]. Primary lung pathology contributed to a (53%) cases of ARDS while the rest (47%) had non pulmonary causes.There was not any significant different in mortality between these two groups. Similarly when infections and non infections conditions were considered separately there was no difference in survival. All children were ventilated using Pressure Controlled Ventilation. The mean (SD) duration of ventilation was 5.0 days [range 1-10 days]. The maximum PEEP (SD) used during the course of ventilation was 10 (3.37) cm H2O [range 7- 18], while the maximum PIP (SD) used was 31 (3.75) cm H2O (range 25-36). The overall mortality was 70%; highest in children less than 2 years of age. Majority of the children had shock as the most common comorbid factor and had a high mortality (73.3%). Conclusion. The high incidence and mortality of ARDS and the presence of a large proportion of potentially preventable accidents and poisoning cases in the study group underline the need for health education measures addressing preventive strategies among the rural population.

Single versus multiple courses of antenatal betamethasone and neonatal outcome: a randomized controlled trial.

OBJECTIVES: This study compared the beneficial and adverse neonatal effects of a single versus repeated courses of antenatal betamethasone. SETTING: Tertiary care hospital DESIGN: Open labeled, randomized controlled trial. PARTICIPANTS: Pregnant women (26-33 weeks) at risk of preterm delivery, who received one course of antenatal betamethasone and remained undelivered for 7 days.Those with uncertain gestation, major malformations and frank chorioamnionitis were excluded. INTERVENTIONS: Subjects were randomized to receive weekly antenatal betamethasone until 34 weeks or no further betamethasone. OUTCOME MEASURES: Primary: incidence of severe respiratory distress syndrome (RDS). Secondary: incidence of non-severe RDS and other neonatal morbidity; birth weight, length and occipito-frontal circumference (OFC); and, development and growth at 6 mo corrected age. RESULTS: 38 subjects were allocated to each group. Severe RDS was similar in multiple and single course groups (7% vs. 3% respectively, P=0.34), as was incidence of other morbidity. Composite outcome of RDS and or death within 28 days tended to be less in multiple course group (P=0.07). Birth anthropometry was similar in the 2 groups. At 6 mo corrected age (n=44), weight and length were significantly lower in multiple course group (p=0.003 and P=0.007, respectively), whereas OFC was not different (P=0.1). There were no differences vis a vis neurodevelopmental outcomes. CONCLUSIONS: A single course of antenatal betamethasone was as efficacious as multiple courses, with respect to prevention of neonatal morbidity. Multiple antenatal betamethasone courses have long-term adverse effects on infant weight and length growth, but not on OFC and neurodevelopment.

Respiratory viruses in hospitalized children with acute lower respiratory tract infections, Mazandaran Province, Iran.

We conducted this study to determine the contribution of respiratory viruses in 202 hospitalized children (1 mo-5 yr) with clinical evidence of acute lower respiratory tract illness (ALRI). Nasopharyngeal specimens were assayed for viruses detection by indirect immunoflourescent method. Viral agents were identified from 109 (54%) cases (9 cases had dual infection). The most commonly detected virus was parainfluenza virus 3 in 32 (15.8%) cases followed by respiratory syncytial virus 26 (12.9%) parainfluenza 1 and parainfluenza 2 each 13 (6.4%) influenza A 16 (7.4%), influenza B; 7(3.5%), and adenovirus 12 (5.9%). There were no demographic, clinical, radiologic or laboratory parameters except for recurrent wheeze (OR: 4.47; (95% CI: 1.98-10.73) and fever (OR: 3.27; (95% CI: 1.73-6.20), which could differentiate between patients with or without viral etiology.

Síndrome do desconforto respiratório agudo pulmonar e extrapulmonar: existem diferenças? / Pulmonary and extrapulmonary acute respiratory distress syndrome: are they different?

JUSTIFICATIVA E OBJETIVOS: A patogênese da síndrome do desconforto respiratório agudo (SDRA) tem sido explicada pela presença de uma agressão direta (SDRA pulmonar) e/ou indireta (SDRA extrapulmonar) ao parênquima pulmonar. Evidências indicam que a fisiopatologia da doença pode diferir com o tipo de lesão. O objetivo deste estudo foi apresentar breve revisão das diferenças entre a SDRA pulmonar e a SDRA extrapulmonar e discutir as interações entre os aspectos morfofuncionais e a resposta aos diferentes tratamentos. CONTEÚDO: Esta revisão bibliográfica baseou-se em uma pesquisa sistemática de artigos experimentais e clínicos sobre SDRA incluídos nas bases de dados MedLine e SciElo nos últimos 20 anos. Muitos pesquisadores concordam, com base em estudos experimentais, que a SDRA pulmonar e a SDRA extrapulmonar não são idênticas no que diz respeito aos aspectos morfofuncionais, a resposta à pressão positiva ao final da expiração (PEEP), manobra de recrutamento alveolar, posição prona e outras terapias farmacológicas. Entretanto, os estudos clínicos têm descrito resultados contraditórios, os quais podem ser atribuídos à dificuldade de se classificar a SDRA em uma ou outra etiologia, e de se precisar o início, a fase e a gravidade da SDRA nos pacientes. CONCLUSÕES: Pacientes com SDRA de etiologias distintas perduram sendo considerados como pertencendo a uma mesma síndrome e, assim, são tratados da mesma forma. Logo, é fundamental entender as diferenças fisiopatológicas entre a SDRA pulmonar e extrapulmonar para que a terapia seja mais bem direcionada.

BACKGROUND AND OBJECTIVES: The pathogenesis of acute respiratory distress syndrome (ARDS) has been described by the presence of direct (pulmonary) and/or indirect (extrapulmonary) insult to the lung parenchyma. Evidence indicates that the pathophysiology of ARDS may differ according to the type of primary insult. This article presents a brief overview of differences between pulmonary and extrapulmonary ARDS, and discusses the interactions between morpho-functional aspects and response to differents therapies, both in experimental and clinical studies. CONTENTS: This systematic review included clinical and experimental ARDS studies found in MedLine and SciElo databases in the last 20 years. Many researchers acknowledge that experimental pulmonary and extrapulmonary ARDS are not identical with regard to morpho-functional aspects, the response to positive end-expiratory pressure (PEEP), recruitment manoeuvre, prone position and other adjunctive therapies. However, contradictory results have been reported in different clinical studies, which could be attributed to the difficulty of classifying ARDS in one or the other category, and to the assurance regarding the onset, phase and severity of ARDS in all patients. CONCLUSIONS: Heterogeneous ARDS patients are still considered as belonging to one syndrome, and are therefore treated in a similar manner. Thus, it is important to understand the pathophysiology of pulmonary and extrapulmonary ARDS in an attempt to better treat these patients.

Lesão pulmonar aguda associada à transfusão / Transfusion-related acute lung injury

Lesão pulmonar aguda associada à transfusão (transfusion-related acute lung injury, TRALI) é uma complicação clínica grave relacionada à transfusão de hemocomponentes que contêm plasma. Recentemente, TRALI foi considerada a principal causa de morte associada à transfusão nos Estados Unidos e Reino Unido. É manifestada tipicamente por dispnéia, hipoxemia, hipotensão, febre e edema pulmonar não cardiogênico, que ocorre durante ou dentro de 6 h, após completada a transfusão. Embora o exato mecanismo não tenha sido totalmente elucidado, postula-se que TRALI esteja associada à infusão de anticorpos contra antígenos leucocitários (classes I ou II ou aloantígenos específicos de neutrófilos) e a mediadores biologicamente ativos presentes em componentes celulares estocados. A maioria dos doadores implicados em casos da TRALI são mulheres multíparas. TRALI, além de ser pouco diagnosticada, pode ainda ser confundida com outras situações de insuficiência respiratória aguda. Um melhor conhecimento sobre TRALI pode ser crucial na prevenção e tratamento desta severa complicação transfusional.

Transfusion-related acute lung injury (TRALI) is a serious clinical syndrome associated with the transfusion of plasma-containing blood components. Recently, TRALI has come to be recognized as the leading cause of transfusion-related death in the United States and United Kingdom. This complication typically presents as shortness of breath, hypoxemia, hypotension, fever and noncardiogeneic pulmonary edema, all occurring during or within 6 h after transfusion. Although the mechanism of TRALI has not been fully elucidated, it has been associated with human leukocyte antigen antibodies (class I, class II or neutrophil alloantigens) and with biologically active mediators in stored cellular blood components. Most of the donors implicated in cases of TRALI are multiparous women. Rarely diagnosed, TRALI can be confused with other causes of acute respiratory failure. Greater knowledge regarding TRALI on the part of clinicians could be crucial in preventing and treating this severe complication of blood transfusion.

Síndrome de distrés respiratorio agudo, experiencia en una UTI / Acute syndrome of distrés respiratory, experience in a UTI

El Sindrome de Distrés Respiratorio Agudo es frecuente con mortalidad elevada, que requiere cuidados críticos. En niños con pulmones sanos, puede surgir insuficiencia respiratoria aguda por daño de la unidad alveolocapilar ocasionado por diversos agentes, siendo la manifestación más grave de la lesión del parénquima pulmonar. Objetivos: conocer las características epidemiológicas del SDRA en nuestra UTIP. Material: revisión de 359 historias clínicas de enero de 2003 a diciembre de 2005, con 38 pacientes que presentaron 40 episodios de SDRA, dos pacientes con 2 episodios en la misma internación. Método: retrospectivo, descriptivo y corte transversal. Criterios de inclusión: a. Oxigenación alterada: PaO2/FiO2 <200 b. Infiltrados pulmonares bilaterales en radiografía de tórax c. Ausencia de signos de aumento de presión y duración del SDRA, valores de PaO2/FiO2 y PEEP, días del ARM. Se dividieron las causas en pulmonares y extrapulmonares; infecciosas y no infecciosas. Se registraron la morbilidad, la mortalidad global y la atribuible al SRDA. Resultados: Edad promedio 3,73 años. El 42 % (16/38) de sexo femenino y 58% (22/38) masculino. El día de inicio del SDRA en promedio fue el día 4º de internación; 55% fue diagnosticado al ingreso. La duración del cuadro promedio fue 4,92 días y de ARM 10,2 días. Causas desencadenantes: 65%(26/40) de origen pulmonar y 35%(14/40) extrapulmonar, siendo 100% de origen infecciosos con aislamiento bateriológico del 40(16/40). La PaO2/FiO2 al inicio en promedio fue 67,75 y en el momento de mayor gravedad 40,3. PEEP requerida: entre 5 y 19 cmH2O, en promedio de 10. Presentaron complcaciones respiratorias un 42% de la población (17/40). La mortalidad global fue 74%(28/38). Conclusión : más de la mitad de los casos se presentaron al ingreso y las causas desencadenantes fueron de origen infeccioso y causas pulmonares, con bajo aislamiento etiológico. La mortalidad fue elevada pero de dentro de la descripta en la literatura mundial.

Correlation between timing of ASV administration and complications in snake bites.

AIMS OF STUDY : The present study was undertaken to study the relationship between the time of anti-snake venom (ASV) administration due to late arrival of patient at hospital and subsequent development of complications. MATERIAL AND METHODS: All patients of snake bite that presented to our institution over a period of 1 1/2 years were included in the present study. A detailed clinical history, clinical examination and investigations were carried out. The patients were administered ASV within 10 minutes of presentation. The bite to needle time (time between the bite and start of ASV) was noted. The patients were then followed up to note any subsequent development of complications. The end-point of the study was normalization of haematological and neurological parameters. RESULTS: Fifty patients became eligible for the study. Twenty patients (40%) had complications while remaining 30 patients (60%) were uncomplicated. An attempt was made to study relationship between bite to needle time and subsequent development of complications. It was found to be significant at 5% level of significance (p<0.05) by chi square test. CONCLUSION: Incidence of complications was directly proportional to the duration of venom in the blood prior to neutralization by ASV due to late arrival of patient at hospital. The early institution of ASV is beneficial in preventing complications however severe is the systemic envenomation.

Acute lung injury and acute respiratory distress syndrome.

Acute lung injury and acute respiratory distress syndrome are an important challenge for pediatric intensive care units. These disorders are characterized by a significant inflammatory response to a local (pulmonary) or remote (systemic) insult resulting in injury to alveolar epithelial and endothelial barriers of the lung, acute inflammation and protein rich pulmonary edema. The reported rates in children vary from 8.5 to 16 cases / 1000 pediatric intensive care unit (PICU) admissions. The pathological features of ARDS are described as passing through three overlapping phases - an inflammatory or exudative phase (0-7 days), a proliferative phase (7-21 days) and lastly a fibrotic phase (from day 10). The treatment of ARDS rests on good supportive care and control of initiating cause. The goal of ventilating patients with ALI/ARDS should be to maintain adequate gas exchange with minimal ventilator induced lung injury. This can be achieved by use of optimum PEEP, low tidal volume and appropriate FiO2. High frequency ventilation can improve oxygenation but does affect the outcomes. Prone positioning is a useful strategy to improve oxygenation. Pharmacological strategies have not made any significant impact on the outcomes. Preliminary data suggests some role for use of corticosteroids in non-resolving ARDS. The mortality rates have declined over the last decade chiefly due to the advances in supporting critically ill patients.

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

Síndrome de dificultad respiratoria del adulto: tratamiento y estrategia ventilatoria / Acute respiratory distress syndrome: therapeutic interventions and ventilatory strategy

El síndrome de dificultad respiratoria agudo responde a múltiples etiologías tales como sepsis, neumonía, peritonitis y trauma múltiple entre otras y es un proceso inflamatorio difuso y generalizado del pulmón. Su evolución depende de muchos factores que incluyen la severidad del cuadro clínico, la enfermedad fundamental y el desarrollo de fallo multiorgánico. A pesar de ser un proceso universal en el pulmón existen diferencias funcionales según se trate de un SDRA de curso primario (ej. Neumonía) o SDRA secundario (ej. Sepsis no pulmonar). Durante los últimos 20 años ha habido cambios fundamentales en las estrategias ventilatorias de estos pacientes. Esto tiene influencia fundamental en mejorar la PaO2 y se denominan estrategias de reclutamiento alveolar. En esta publicación sobre SDRA actualizamos los nuevos conocimientos fisiopatológicos de esta entidad como así también las estrategias ventilatorias que han demostrado tener impacto en la evolución de los pacientes con SDRA.