Treatment of intrauterine adhesions in rats with hypoxia-cultured BMSC-derived exosomes / 中华妇产科杂志

Objective: To perform intrauterine adhesion modeling, and to investigate the repair effect of hypoxic treated bone marrow mesenchymal stem cells (BMSC) and their derived exosomes (BMSC-exo) on endometrial injury. Methods: BMSC and their exosomes BMSC-exo extracted from rats' femur were cultured under conventional oxygen condition (21%O2) or hypoxia condition (1%O2). Intrauterine adhesion modeling was performed on 40 healthy female SD rats by intrauterine injection of bacterial lipopolysaccharide after curettage. On the 28th day of modeling, 40 rat models were randomly divided into five groups, and interventions were performed: (1) NC group: 0.2 ml phosphate buffered solution was injected into each uterine cavity; (2) BMSC group: 0.2 ml BMSC (1×106/ml) with conventional oxygen culture was injected intrauterine; (3) L-BMSC group: 0.2 ml of hypoxic cultured BMSC (1×106/ml) was injected intrauterine; (4) BMSC-exo group: 0.2 ml of BMSC-exo cultured with conventional oxygen at a concentration of 500 μg/ml was injected into the uterine cavity; (5) L-BMSC-exo group: 0.2 ml hypoxic cultured BMSC-exo (500 μg/ml) was injected intrauterine. On the 14th and 28th day of treatment, four rats in each group were sacrificed by cervical dislocation after anesthesia, and endometrial tissues were collected. Then HE and Masson staining were used to observe and calculate the number of glands and fibrosis area in the endometrium. The expressions of angiogenesis related cytokines [vascular endothelial growth factor A (VEGFA) and CD31], and fibrosis-related proteins [collagen-Ⅰ, collagen-Ⅲ, smooth muscle actin α (α-SMA), and transforming growth factor β1 (TGF-β1)] in endometrial tissues were detected by western blot. Results: (1) HE and Masson staining showed that the number of endometrial glands in L-BMSC group, BMSC-exo group and L-BMSC-exo group increased and the fibrosis area decreased compared with NC group on the 14th and 28th day of treatment (all P<0.05). Noteworthily, the changes of L-BMSC-exo group were more significant than those of BMSC-exo group (all P<0.05), and the changes of BMSC-exo group were greater than those of BMSC group (all P<0.05). (2) Western blot analysis showed that, compared with NC group, the expressions of collagen-Ⅲ and TGF-β1 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group decreased on the 14th and 28th day of treatment (all P<0.05). As the treatment time went on, the expressions of fibrosis-related proteins were different. Compared with BMSC group, the expressions of collagen-Ⅲ, α-SMA and TGF-β1 in the BMSC-exo group and L-BMSC group decreased on the 28th day (all P<0.05). Moreover, the expressions of collagen-Ⅲ and TGF-β1 in L-BMSC-exo group were lower than those in BMSC-exo group on the 28th day (all P<0.05). And the expressions of collagen-Ⅰ, α-SMA and TGF-β1 in L-BMSC-exo group were lower than those in L-BMSC group on the 28th day (all P<0.05). (3) The results of western blot analysis of VEGFA and CD31 showed that, the expressions of VEGFA and CD31 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group increased on the 14th and 28th day of treatment compared with NC group (all P<0.05). Treatment for 28 days, the expressions of VEGFA and CD31 in BMSC-exo group and CD31 in L-BMSC group were higher than those in BMSC group (all P<0.05). Moreover, the expressions of VEGFA and CD31 in L-BMSC-exo group were higher than those in BMSC-exo group and L-BMSC group on the 28th day (all P<0.05). Conclusions: Treatment of BMSC and their exosomes BMSC-exo with hypoxia could promote endometrial gland hyperplasia, inhibit tissue fibrosis, and further repair the damaged endometrium in rats with intrauterine adhesion. Importantly, hypoxic treatment of BMSC-exo is the most effective in intrauterine adhesion rats.

El paciente pediátrico crítico con COVID-19. Puesta al día / Critically-ill pediatric patients with COVID-19. An update

La pandemia por COVID-19 ha acaparado la atención mundial. Los distintos países se esfuerzan en optimizar recursos y brindar tratamientos efectivos en la medida que estos son avalados por la evidencia, con un ritmo de producción acorde a la urgencia. En el ámbito pediátrico, el COVID-19 acarrea una baja tasa de gravedad, en comparación con la población adulta. Un 6 % de los casos presentan una evolución grave, que se observa en los pacientes menores de 1 año de edad y/o con patologías subyacentes.Los enfoques terapéuticos en los pacientes pediátricos con COVID-19 no están claros. La escasa casuística en pediatría dificulta realizar recomendaciones en el paciente crítico que estén sustentadas en la evidencia. Esta revisión tiene como objetivo resumir las distintas publicaciones existentes sobre el curso de esta enfermedad y su tratamiento en los pacientes pediátricos críticamente enfermos

The COVID-19 pandemic has grabbed worldwide attention. The different national governments are making an effort to optimize resources and provide effective treatments inasmuch as they are supported by the evidence, at a rate of production in line with the pressing needs. In the field of pediatrics, COVID-19 has a low severity rate compared to the adult population. Approximately 6 % of cases present with a severe course, accounting for patients younger than 1 year and/or with underlying conditions.The therapeutic approach to pediatric patients with COVID-19 is unclear. The small number of pediatric cases hinders the possibility of making evidence-based recommendations for critically-ill patients. The objective of this review is to summarize the different current publications about the clinical course of COVID-19 and its management in critically-ill pediatric patien

O uso de níveis altos de PEEP previne a lesão pulmonar induzida pelo ventilador? / Does the use of high PEEP levels prevent ventilator-induced lung injury?

RESUMO A distensão excessiva e o recrutamento alveolar pelo volume corrente foram defendidos como os principais mecanismos físicos responsáveis pela lesão pulmonar induzida pelo ventilador. A limitação do volume corrente demonstrou benefícios quanto à sobrevivência em pacientes com síndrome da angústia respiratória aguda e é reconhecida como a pedra fundamental da ventilação protetora. Em contraste, o uso de elevados níveis de pressão positiva expiratória final em estudos clínicos gerou resultados conflitantes e ainda é um assunto controvertido. Nesta revisão, discutimos os benefícios e as limitações da abordagem de pulmão aberto, e debatemos alguns recentes estudos experimentais e clínicos, referentes ao uso de níveis baixos e moderados de pressão positiva expiratória final. Também distinguimos o estiramento dinâmico (volume corrente) do estático (pressão expiratória final positiva e pressão média nas vias aéreas) e discutimos seus papéis na indução da lesão pulmonar induzida pela ventilação. As estratégias com elevada pressão positiva expiratória final claramente diminuem a hipoxemia refratária em pacientes com síndrome da angústia respiratória aguda, porém também aumentam o estiramento estático, que, por sua vez, pode ser lesiva aos pacientes, especialmente para aqueles com nível mais baixo de recrutabilidade pulmonar. Em pacientes com insuficiência respiratória grave, recomenda-se a titulação da pressão positiva expiratória final contra a gravidade da hipoxemia, ou sua aplicação de uma forma decrescente após manobra de recrutamento. Caso sejam observadas elevadas pressões de platô, driving pressure ou pressão média nas vias aéreas, a posição prona ou ventilação ultraprotetora podem ser indicadas para melhora da oxigenação, sem estresse adicional e estiramento dos pulmões.

ABSTRACT Overdistention and intratidal alveolar recruitment have been advocated as the main physical mechanisms responsible for ventilator-induced lung injury. Limiting tidal volume has a demonstrated survival benefit in patients with acute respiratory distress syndrome and is recognized as the cornerstone of protective ventilation. In contrast, the use of high positive end-expiratory pressure levels in clinical trials has yielded conflicting results and remains controversial. In the present review, we will discuss the benefits and limitations of the open lung approach and will discuss some recent experimental and clinical trials on the use of high versus low/moderate positive end-expiratory pressure levels. We will also distinguish dynamic (tidal volume) from static strain (positive end-expiratory pressure and mean airway pressure) and will discuss their roles in inducing ventilator-induced lung injury. High positive end-expiratory pressure strategies clearly decrease refractory hypoxemia in patients with acute respiratory distress syndrome, but they also increase static strain, which in turn may harm patients, especially those with lower levels of lung recruitability. In patients with severe respiratory failure, titrating positive end-expiratory pressure against the severity of hypoxemia, or providing it in a decremental fashion after a recruitment maneuver, is recommended. If high plateau, driving or mean airway pressures are observed, prone positioning or ultraprotective ventilation may be indicated to improve oxygenation without additional stress and strain in the lung.

Severe hypoxemia during veno-venous extracorporeal membrane oxygenation: exploring the limits of extracorporeal respiratory support

OBJECTIVE: Veno-venous extracorporeal oxygenation for respiratory support has emerged as a rescue alternative for patients with hypoxemia. However, in some patients with more severe lung injury, extracorporeal support fails to restore arterial oxygenation. Based on four clinical vignettes, the aims of this article were to describe the pathophysiology of this concerning problem and to discuss possibilities for hypoxemia resolution. METHODS: Considering the main reasons and rationale for hypoxemia during veno-venous extracorporeal membrane oxygenation, some possible bedside solutions must be considered: 1) optimization of extracorporeal membrane oxygenation blood flow; 2) identification of recirculation and cannula repositioning if necessary; 3) optimization of residual lung function and consideration of blood transfusion; 4) diagnosis of oxygenator dysfunction and consideration of its replacement; and finally 5) optimization of the ratio of extracorporeal membrane oxygenation blood flow to cardiac output, based on the reduction of cardiac output. CONCLUSION: Therefore, based on the pathophysiology of hypoxemia during veno-venous extracorporeal oxygenation support, we propose a stepwise approach to help guide specific interventions. .

Recomendações para oxigenoterapia domiciliar prolongada em crianças e adolescentes / Recommendations for long-term home oxygen therapy in children and adolescents

OBJETIVO: Orientar pediatras, neonatologistas, pneumologistas, pneumologistas pediátricos e outros profissionais envolvidos na área sobre as principais indicações e as particularidades da oxigenoterapia domiciliar prolongada em crianças e adolescentes. FONTES DOS DADOS: Pesquisa bibliográfica na base de dados MEDLINE/PubMed (1990 a 2011). Adicionalmente, referências de estudos selecionados foram incluídas. Como para muitos dos aspectos não existem evidências científicas consistentes, algumas recomendações citadas foram feitas com base em experiência clínica. SÍNTESE DOS DADOS: Oxigenoterapia domiciliar prolongada tem sido uma prática crescente nos pacientes pediátricos e se encontra indicada em casos de displasia broncopulmonar, fibrose cística, bronquiolite obliterante, pneumopatias intersticiais, hipertensão pulmonar, etc. Ressaltam-se como benefícios: redução de internações, otimização do crescimento físico e do desenvolvimento neurológico, melhora da tolerância ao exercício e da qualidade do sono e prevenção da hipertensão pulmonar/. Os níveis de saturação de oxigênio indicativos para a oxigenoterapia diferem dos estabelecidos para adultos com doença pulmonar obstrutiva crônica e variam de acordo com a doença e faixa etária. Para a avaliação da saturação de oxigênio, utiliza-se a oximetria de pulso, sendo a gasometria arterial dispensável. Há três fontes de oxigênio disponíveis: cilindros gasosos, oxigênio líquido e concentradores de oxigênio. Os fluxos utilizados costumam ser menores, assim como o número de horas/dia necessários, quando comparados ao uso em adultos. Em algumas doenças há melhora, e a suspensão do oxigênio é possível. CONCLUSÕES: Oxigenoterapia domiciliar prolongada é uma terapêutica cada vez mais comum em pediatria e suas indicações são numerosas. Há particularidades relevantes quando comparada aos adultos em relação às indicações, modo de uso e monitorização.

OBJECTIVE: To advise pediatricians, neonatologists, pulmonologists, pediatric pulmonologists, and other professionals in the area on the main indications and characteristics of long-term home oxygen therapy in children and adolescents. DATA SOURCE: A literature search was carried out in the MEDLINE/PubMed database (1990 to 2011). Additionally, references from selected studies were included. As consistent scientific evidence does not exist for many aspects, some of the recommendations were based on clinical experience. DATA SYNTHESIS: Long-term home oxygen therapy has been a growing practice in pediatric patients and is indicated in bronchopulmonary dysplasia, cystic fibrosis, bronchiolitis obliterans, interstitial lung diseases, and pulmonary hypertension, among others. The benefits are: decrease in hospitalizations, optimization of physical growth and neurological development, improvement of exercise tolerance and quality of sleep, and prevention of pulmonary hypertension/cor pulmonale. The levels of oxygen saturation indicative for oxygen therapy differ from those established for adults with chronic obstructive pulmonary disease, and vary according to age and disease. Pulse oximetry is used to evaluate oxygen saturation; arterial blood gas is unnecessary. There are three available sources of oxygen: gas cylinders, liquid oxygen, and oxygen concentrators. The flows used are usually smaller, as are the number of hours/day needed when compared to the use in adults. Some diseases show improvement and oxygen therapy discontinuation is possible. CONCLUSIONS: Long-term home oxygen therapy is increasingly common in pediatrics and has many indications. There are relevant particularities when compared to its use in adults, regarding indications, directions for use, and monitoring.

Hepatitis hipóxica / Hypoxic hepatitis

Hypoxic hepatitis (HH), or ischemic hepatitis occurs in the context of cardiac, circulatory or respiratory failure and is characterized by a sharp increase in serum aminotransferase levels due to anoxic necrosis of centrilobular liver cells. It is frequently observed in the ICU and has been associated to increased patient morbidity and mortality. Hepatic ischemia in the presence of a shock state is the main hemodynamic mechanism. However, other hemodynamic mechanisms of hypoxia, such as hepatic passive congestion, arterial hypoxemia and tissue dysoxia play an important role. Shock state is observed in only 50 percent of the cases. HH therapy of depends primarily on the nature of the underlying condition. Patients with HH have poor prognosis with more than 50 percent of mortality during the hospital stay.

Hepatitis hipóxica (HH) o hepatitis isquémica se presenta en el contexto de insuficiencia cardíaca, respiratoria o circulatoria y se caracteriza por aumento brusco de transaminasas debido a la necrosis por anoxia de las células centrilobulillares del hígado. La HH es frecuente en UCI y está asociada a un aumento en la morbilidad y mortalidad. La isquemia hepática por un estado de shock es la principal causa. Sin embargo, mecanismos de hipoxia como la congestión pasiva del hígado, hipoxemia arterial y disoxia tisular juegan un importante rol. Se shock observa en sólo 50 por ciento de los casos. El tratamiento depende primariamente de la causa subyacente. Los pacientes con HH tienen un mal pronóstico con más de 50 por ciento de mortalidad intrahospitalaria.

First-year experience of a Brazilian tertiary medical center in supporting severely ill patients using extracorporeal membrane oxygenation

OBJECTIVES: The aim of this manuscript is to describe the first year of our experience using extracorporeal membrane oxygenation support. METHODS: Ten patients with severe refractory hypoxemia, two with associated severe cardiovascular failure, were supported using venous-venous extracorporeal membrane oxygenation (eight patients) or veno-arterial extracorporeal membrane oxygenation (two patients). RESULTS: The median age of the patients was 31 yr (range 14-71 yr). Their median simplified acute physiological score three (SAPS3) was 94 (range 84-118), and they had a median expected mortality of 95% (range 87-99%). Community-acquired pneumonia was the most common diagnosis (50%), followed by P. jiroveci pneumonia in two patients with AIDS (20%). Six patients were transferred from other ICUs during extracorporeal membrane oxygenation support, three of whom were transferred between ICUs within the hospital (30%), two by ambulance (20%) and one by helicopter (10%). Only one patient (10%) was anticoagulated with heparin throughout extracorporeal membrane oxygenation support. Eighty percent of patients required continuous venous-venous hemofiltration. Three patients (30%) developed persistent hypoxemia, which was corrected using higher positive end-expiratory pressure, higher inspired oxygen fractions, recruitment maneuvers, and nitric oxide. The median time on extracorporeal membrane oxygenation support was five (range 3-32) days. The median length of the hospital stay was 31 (range 3-97) days. Four patients (40%) survived to 60 days, and they were free from renal replacement therapy and oxygen support. CONCLUSIONS: The use of extracorporeal membrane oxygenation support in severely ill patients is possible in the presence of a structured team. Efforts must be made to recognize the necessity of extracorporeal respiratory support at an early stage and to prompt activation of the extracorporeal membrane oxygenation team.

Hypoxia/reoxygenation-induced myocardial lesions in newborn piglets are related to interindividual variability and not to oxygen concentration

OBJECTIVE: Evaluation of myocardial histological changes in an experimental animal model of neonatal hypoxiareoxygenation. METHODS: Normocapnic hypoxia was induced in 40 male Landrace/Large White piglets. Reoxygenation was initiated when the animals developed bradycardia (HR <60 beats/min) or severe hypotension (MAP <15 mmHg). The animals were divided into four groups based on the oxygen (O2) concentration used for reoxygenation; groups 1, 2, 3, and 4 received 18%, 21%, 40%, and 100% O2, respectively. The animals were further classified into five groups based on the time required for reoxygenation: A: fast recovery (<15 min); B: medium recovery (15-45 min); C: slow recovery (45-90 min); D: very slow recovery (>90 min), and E: nine deceased piglets. RESULTS: Histology revealed changes in all heart specimens. Interstitial edema, a wavy arrangement, hypereosinophilia and coagulative necrosis of cardiomyocytes were observed frequently. No differences in the incidence of changes were observed among groups 1-4, whereas marked differences regarding the frequency and the degree of changes were found among groups A-E. Coagulative necrosis was correlated with increased recovery time: this condition was detected post-asphyxia in 14%, 57%, and 100% of piglets with fast, medium, and slow or very slow recovery rates, respectively. CONCLUSIONS: The significant myocardial histological changes observed suggest that this experimental model might be a reliable model for investigating human neonatal cardiac hypoxia-related injury. No correlation was observed between the severity of histological changes and the fiO2 used during reoxygenation. Severe myocardial changes correlated strictly with recovery time, suggesting an unreported individual susceptibility of myocardiocytes to hypoxia, possibly leading to death after the typical time-sequence of events.

Oxígenoterapia y rehabilitación respiratoria en el paciente con enfermedad pulmonar obstructiva crónica / Oxygen therapy and pulmonary rehabilitation in patients with chronic obstructive pulmonary disease

Patients with chronic obstructive pulmonary disease (COPD) often have severe shortness of breath that prevents them from performing their everyday activities. Pulmonary rehabilitation programs improve capacity exercise, decrease breathlessness and enhance quality of life. In addition, the use of oxygen has been demonstrated to reduce ventilatory demand and to induce improvements in metabolism, muscle function, and cardiovascular function. The combination of exercise training and supplemental oxygen may provide additional benefit. This chapter therefore evaluated the scientific evidence regarding the beneficial effect of supplemental oxygen in the pulmonary rehabilitation of patients with COPD. Supplemental oxygen should be recommended in all COPD patients with resting hypoxemia during rehabilitative exercise training (quality evidence A, strong recommendation). Also, in COPD patients without resting hypoxemia was recommended to use supplemental oxygen during respiratory rehabilitation, because it allows a longer time of exercise and reduces dyspnea (quality evidence B, weak recommendation).

Los pacientes con enfermedad pulmonar obstructiva crónica (EPOC) a menudo tienen dificultad respiratoria severa que les impide realizar sus actividades cotidianas. Los programas de rehabilitación pulmonar mejoran la capacidad de ejercicio, disminuyen la disnea y mejoran la calidad de vida. En adición, el uso de oxígeno ha demostrado una reducción de la demanda ventilatoria y mejorías en el metabolismo, la función muscular y la función cardiovascular. La combinación de entrenamiento muscular y suplemento de oxígeno puede proporcionar un beneficio adicional. En este capitulo se evaluó la evidencia científica que existe en cuanto al beneficio del uso del suplemento de oxigeno en la rehabilitación respiratoria en pacientes con EPOC. Se recomendó el uso de suplemento de oxígeno en todo paciente con EPOC e hipoxemia de reposo durante el entrenamiento muscular (calidad de la evidencia A, recomendación fuerte). Así también, en los pacientes con EPOC y sin hipoxemia de reposo se recomienda utilizar suplemento de oxígeno durante la rehabilitación respiratoria, porque permite tolerar durante mayor tiempo el entrenamiento muscular y reduce la disnea (calidad de la evidencia B, recomendación débil).

Estratégias ventilatórias frente à hipoxemia em cirurgia cardíaca: validação de questionário para anestesiologistas no Brasil / Estrategias ventilatorias frente a la hipoxemia en cirugía cardíaca: validación de cuestionario para anestesiólogos en Brasil / Ventilatory strategies for hypoxemia during cardiac surgery: survey validation for anesthesiologists in Brazil

JUSTIFICATIVA E OBJETIVOS: A hipoxemia perioperatória ocorre frequentemente em cirurgia cardíaca e a atelectasia é sua principal causa. Além disso, podemos citar como causas circulação extracorpórea (CEC), dissecção de artérias torácicas internas, status clínico prévio do paciente, entre outras. O presente estudo elaborou um questionário anônimo para observar as estratégias ventilatórias frente à hipoxemia em cirurgia cardía ca adotadas por cinco mil anestesiologistas distribuídos no país. MÉTODO: Foram enviados questionários por e-mail a cinco mil anestesiologistas do Brasil. RESULTADOS: Dos questionários enviados, foram recebidas 81 respostas válidas. Dentre as respostas, 65 (80 por cento) anestesiologistas fazem uso da ventilação controlada a volume (VCV) frente a 16 (20 por cento) que preferem ventilação controlada à pressão (PCV). O volume (Vt) corrente utilizado é inferior a 10 mL.kg-1 para 46 (61 por cento) contra 29 (39 por cento) que adotam um Vt maior que 10 mL.kg-1. Quarenta e sete (58 por cento) usam PEEP e 17 (21 por cento) utilizam FiO2 acima de 60 por cento. No caso de hipoxemia intraoperatória, 20,9 por cento aumentam ou introduzem PEEP, 70,3 por cento aumentam a FiO2, 19,7 por cento realizam manobra de recrutamento alveolar, 13,5 por cento aumentam o volume-corrente e 20,9 por cento realizam checagem de falhas no aparelho de anestesia. As respostas foram enviadas de 15 estados. CONCLUSÕES: As condutas descritas nos questionários respondidos são compatíveis com a literatura internacional. Com ajuste no formato do questionário e na abordagem aos anestesiologistas, novos estudos poderão ser realizados.

BACKGROUND AND OBJECTIVES: Perioperative hypoxemia is common in cardiac surgeries, and atelectasis is the main cause. Besides, we can mention extracorporeal circulation (ECC), dissection of internal thoracic arteries, and previous clinical status of the patient among others as its causes. The present study elaborated an anonymous questionnaire to observe ventilatory strategies for hypoxemia in cardiac surgeries adopted by five thousand anesthesiologists all over the country. METHODS: Questionnaires were sent via e-mail for five thousand anesthesiologists in Brazil. RESULTS: Out of the questionnaires sent, 81 valid responses were received. Among the answers, 65 (80 percent) anesthesiologists use volume-controlled ventilation (VCV), while 16 (20 percent) prefer pressure-controlled ventilation (PCV). The tidal volume (Vt) used is lower than 10 mL.kg-1, for 46 (61 percent) versus 20 (30 percent) who adopt a Vt greater than 10 mL.kg-1. Forty-seven (58 percent) use PEEP and 15 (21 percent) use FiO2 above 60 percent. In the case of intraoperative hypoxemia, 20.9 percent increase or introduce PEEP, 70.3 percent increase the FiO2, 19.7 percent use alveolar recruitment maneuvers, 13.5 percent increase the tidal volume, and 20.9 percent check for the presence of failures in the anesthesia equipment. Responses were sent from 15 states. CONCLUSIONS: The conducts described in the questionnaires are compatible with those of the international literature. Adjusting the questionnaires format and the way to approach anesthesiologists, new studies could be undertaken.

JUSTIFICATIVA Y OBJETIVOS: La hipoxemia perioperatoria ocurre frecuentemente en la cirugía cardíaca, y la atelectasia es su principal causa. Además, podemos citar como causas la circulación extracorpórea (CEC), disección de arterias torácicas internas, status clínico previo del paciente, entre otras. El presente estudio elaboró un cuestionario anónimo para observar las estrategias ventilatorias frente a la hipoxemia en cirugía cardíaca adoptadas por cinco mil anestesiólogos en todo el país. MÉTODO: Fueron enviados cuestionarios por e-mail a cinco mil anestesiólogos de Brasil. RESULTADOS: De los cuestionarios enviados, se recibieron 81 respuestas válidas. Entre las respuestas, 65 (80 por ciento) anestesiólogos usan ventilación controlada a volumen (VCV) frente a 16 (20 por ciento) que prefieren la ventilación controlada a presión (PCV). El volumen (Vt) corriente utilizado es inferior a 10 mL.kg-1 para 46 (61 por ciento) contra 29 (39 por ciento) que adoptan un Vt mayor que 10 mL.kg-1. Cuarenta y siete (58 por ciento) usan PEEP y 17 (21 por ciento) utilizan FiO2 por encima del 60 por ciento. En el caso de hipoxemia intraoperatoria, 20,9 por ciento aumentan o introducen PEEP, un 70,3 por ciento aumentan la FiO2, un 19,7 por ciento realizan maniobra de reclutamiento alveolar, un 13,5 por ciento aumentan el volumen corriente y un 20,9 por ciento realizan el chequeo de fallas en el aparato de anestesia. Las respuestas fueron enviadas desde 15 estados. CONCLUSIONES: Las conductas descritas en los cuestionarios respondidos están a tono con la literatura internacional. Nuevos estudios se podrán hacer ajustando el formato del cuestionario y el abordaje a los anestesiólogos.

Hipertensión pulmonar e hipoxemia grave en recién nacidos / Pulmonary hypertension and severe hypoxemia in newborns

El óxido nítrico inhalado (ONi), mediante vasodilatación pulmonar directa y carencia de efectos sistémicos, constituye el tratamiento ideal para la hipertensión pulmonar del recién nacido (HTPP). Para evaluar la respuesta a dicho tratamiento se presenta la evolución de 16 pacientes internados en una unidad de cuidados intensivos neonatales valorada por cambios en la saturación de O2 (SO2), presión media en la vía aérea (PMVA) y fracción inspirada de O2 (FiO2). Se analizaron dos grupos: 1) bajo tratamiento con ONi en las primeras 72 horas de vida (n=13) –su diagnóstico más frecuente fue aspiración de líquido meconial (SALAM)-; y 2) recién nacidos con insuficiencia respiratoria grave (n=3), refractaria al tratamiento, en los que se inició ONi luego de 14 días de vida.En el grupo 1 se constató un aumento significativo de la SO2 a partir de las primeras 6 horas del tratamiento con ONi. El descenso de FiO2 y de PMVA fue más tardío, con una mortalidad de 23% (2/13). En el grupo 2 se elevó la SO2, permitiendo disminuir el soporte ventilatorio en las primeras 72 horas de la terapia en un caso.Las dosis de ONi utilizadas fueron menores a las 20 ppm en 8/13 pacientes, no se observaron alteraciones plaquetarias, sangrados, metahemoglobinemia, ni se observó efecto rebote al suspender el ONi desde dosis mínimas (2 ppm). En esta unidad, la inclusión de ONi en el tratamiento de la HTPP o insuficiencia respiratoria se asoció con mejoría de la SO2 y a descenso del soporte ventilatorio, sin efectos adversos, con beneficios sobre la terapia global instituida.

Inhaled nitric oxide (iNO) through direct pulmonary vasodilator action and without sistemyc effects, is the gold standard treatment for pulmonary hypertension of the newborn (HTPP). This work was designed with the aim of evaluating the response to this treatment in 16 newborn patients in an intensive care unit, by changes in oxygen saturation (SO2), medium airway pressure (MAP) and inspirited fraction of O2 (FiO2). Two groups were anaylized: 1) under iNO treatment during the first 72 hs of life, where the most frequent diagnosis was meconium aspiration syndrome and 2) newborns with severe respiratory failure (n=3), refractary to treatment, in which iNO was begun after 14 days of life. Among patients of group 1 it was evident an increase in SO2 after the first 6 hs of treatment with iNO. The decrease FiO2 and MAP occurred later. The mortality rate was 23% (2/13) in this group.In group 2 the SO2 increased, leading to a decrease in ventilatory support in the first 72 hours of treatment in one case. iNO doses were lesser than 20 ppm in 8/13 patients, there were neither platelet impairment, nor bleeding or metahemoglobinemia. There was no rebound effect after finishing iNO therapy from minimum doses (2 ppm). In this unit the inclusion of iNO treatment in HTPP or respiratory failure was associated with improvement in SO2 and a decrease in ventilatory support, without adverse effects resulting in a benefit over the globally support therapy.

Aplicação da ventilação não-invasiva em insuficiência respiratória aguda após cirurgia cardiovascular / Application of noninvasive ventilation in acute respiratory failure after cardiovascular surgery

OBJETIVOS: Verificar as respostas ventilatória, de oxigenação e hemodinâmica de pacientes com insuficiência respiratória aguda (IResp) hipoxêmica submetidos a aplicação de ventilação mecânica não-invasiva (VMNI) no pós-operatório de cirurgia cardiovascular, buscando variáveis preditoras de sucesso, e comparar as diferentes modalidades de VMNI. MÉTODOS: No total, 70 pacientes com IResp hipoxêmica foram randomizados em uma das três modalidades de VMNI: pressão positiva contínua em vias aéreas (CPAP) e ventilação com dois níveis pressóricos (PEEP + PS e BiPAP®). Foram analisadas variáveis ventilatórias, de oxigenação e hemodinâmicas nos períodos pré-aplicação, 3, 6 e 12 horas após iniciado o protocolo. RESULTADOS: Foram excluídos 13 pacientes. Dos pacientes restantes, 31 evoluíram para independência do suporte ventilatório, constituindo o grupo sucesso, e 26 necessitaram de intubação orotraqueal, sendo considerados insucesso. Idade e níveis iniciais de freqüência cardíaca (FC) e de freqüência respiratória (FR) apresentaram valores elevados no grupo insucesso (p = 0,042, 0,029 e 0,002, respectivamente). O grupo insucesso apresentou maior número de intercorrências intra-operatórias (p = 0,025). As variáveis de oxigenação elevaram-se somente no grupo sucesso. Dentre as modalidades de VMNI, evoluíram como sucesso 57,9 por cento dos pacientes no grupo ventilador, 57,9 por cento no bi-nível e 47,3 por cento no CPAP. Variáveis de oxigenação e FR apresentaram melhora somente nos grupos com dois níveis pressóricos. CONCLUSÃO: Pacientes com IResp hipoxêmica no pós-operatório de cirurgia cardiovascular apresentaram melhora da oxigenação, da FR e da FC durante a aplicação de VMNI. Em pacientes mais idosos e com valores iniciais de FR e de FC mais elevados, a VMNI não foi suficiente para reverter o quadro de IResp. Modalidades com dois níveis pressóricos apresentaram resultados superiores.

OBJECTIVE: To examine ventilatory response, oxygenation-related, and hemodynamics of patients with hypoxemic acute respiratory failure (ARF) submitted to noninvasive mechanical ventilation (NIV) during the postoperative phase of cardiovascular surgery in order to identify predictive variables of success, and to compare the different types of NIV. METHODS: Seventy patients with hypoxemic ARF were randomized to one of three modalities of NIV - continuous positive airway pressure (CPAP) and ventilation with two pressure levels (PEEP + SP and BiPAP®). Ventilation, oxygenation-related, and hemodynamics variables were analyzed at pre-application, and 3, 6, and 12 hours after the protocol began. RESULTS: Thirteen patients were excluded. Thirty-one patients progressed to independence from ventilatory support and comprised the success group, and 26 required orotracheal intubation and were considered the nonsuccess group. Age, initial heart rate (HR), and respiratory rate (RR) showed elevated levels in the nonsuccess group (p=0.042, 0.029, and 0.002, respectively). A greater number of intraoperative complications were seen in the nonsuccess group (p=0.025). Oxygenation variables increased only in the success group. Among the NIV types, 57.9 percent of patients in the ventilator group, 57.9 percent in the two-pressure levels group, and 47.3 percent in the CPAP group progressed with success. Oxygenation and RR variables showed improvement only in the groups with two pressure levels. CONCLUSION: Patients with hypoxemic ARF in the postoperative stage after cardiovascular surgery showed better oxygenation, RR, and HR during NIV application. In older patients and those with higher baseline RR and HR values, NIV was not sufficient to reverse ARF. The two-pressure level modes showed better results.

Os efeitos da pressão positiva intermitente e do incentivador respiratório no pós-operatório de revascularização miocárdica / The effects of intermittent positive pressure and incentive spirometry in the postoperative of myocardial revascularization

FUNDAMENTO: As complicações pulmonares são causas freqüentes do aumento de morbi-mortalidade nos pacientes submetidos à cirurgia cardíaca. A fisioterapia respiratória tem auxiliado na recuperação destes pacientes. OBJETIVO: Analisar o efeito fisioterapêutico da aplicação da pressão positiva intermitente (RPPI) e do incentivador respiratório (IR) em pacientes submetidos a cirurgia de revascularização do miocárdio. MÉTODOS: Quarenta pacientes foram divididos em dois grupos: um submetido à aplicação do RPPI (n=20) e o outro ao IR (n=20). Os pacientes foram avaliados nos momentos: pré-operatório, 24ª, 48ª e 72ª horas de pós-operatório, sendo aplicados os recursos no período pós-operatório. Analisaram-se os seguintes parâmetros: saturação de oxigênio (SpO2), freqüência respiratória (FR), volume minuto (VM), volume corrente (VC), pressão inspiratória máxima (Pi máx) e pressão expiratória máxima (Pe máx). RESULTADOS: Nas variáveis demográficas e clínicas os grupos foram considerados homogêneos. No grupo submetido à aplicação com o RPPI identificou-se aumento da SpO2 na 48ª (p=0,007) e na 72ª horas (p=0,0001) quando comparado ao grupo IR. Nos parâmetros: FR, VM e VC na comparação entre os grupos não foram encontradas diferenças estatisticamente significativas. No grupo submetido ao IR a Pe máx na 24ª (p=0,02) e na 48ª (p=0,01) horas apresentaram um aumento significativo. CONCLUSÃO: Com o objetivo de reverter mais precocemente a hipoxemia, o RPPI mostrou-se mais eficiente em comparação ao IR; entretanto, para melhorar a força dos músculos respiratórios, o IR foi mais efetivo.

BACKGROUND: Pulmonary complications are important causes of morbidity and fatalities among patients subject to cardiac surgery. The respiratory physiotherapy has been aiding in the recovery of these patient ones. OBJECTIVE: To evaluate the physiotherapeutic effect of intermittent positive pressure breathing (IPPB) and incentive spirometry (IS) in patients submitted to myocardial revascularization surgery. METHODS: Forty patients were divided in two groups: one was submitted to IPPB (n=20) and the other to IS (n=20). The patients were evaluated at the preoperative period and 24, 48 and 72 hours postoperatively, with the resources being applied in the postoperative period. The following parameters were analyzed: oxygen saturation (SpO2), respiratory frequency (RF), minute volume (MV), current volume (CV), maximum inspiratory pressure (Ip max) and maximum expiratory pressure (Ep max). RESULTS: The groups were considered homogeneous regarding the demographic and clinical variables. In the group submitted to IPPB, an increase in SpO2 was observed 48 (p=0.007) and 72 h (p=0.0001) after surgery, when compared to the IS group. As for the RF, MV and CV variables, there were no statistically significant differences between the groups. The group submitted to IS showed a significant increase in the Epmax 24 (p=0.02) and 48 (p=0.01) h after surgery. CONCLUSION: Aiming at reversing hypoxemia earlier, IPPB showed to be more efficient when compared to IS; however, IS was more effective in improving respiratory muscle strength.

Anomalía de Pelger-Huet: reporte de un caso / Pelger-huet anomaly: a case report

La anomalía de Pelger-Huet se observa una limitación de la segmentación nuclear de los granulocitos. La anomalía fue descrita por primera vez por Pelger en 1928, quien consideró que constituía una manifestación de tuberculosis. Huet consideró que la anomalía sería hereditaria y se transmitiría en forma autonómica dominante. Los individuos afectados rara vez presentan neutrófilos o eosinófilos con más de dos lóbulos. En los heterocigotos, el núcleo de los neutrófilos es no segmentado, con forma de pesa o bilobulado. En los homocigotos, la gran mayoría de los neutrófilos presentan núcleos redondos. Esta anomalía afecta aproximadamente a uno de cada 6000 individuos. La migración celular puede estar levemente alterada, pero la función de los granulocitos es normal y los individuos con esta anomalía hereditaria no padecen efectos adversos. Se trata de Rn masculino quien a las pocas horas de vida presenta ictericia neonatal y dificultad respiratoria y hepatoesplenomegalia. Hallazgos paraclínicos incompatibilidad de grupo sanguíneo, reacción leucemoide 98000 globulos blancos, PCR (-), e hiperbilirrubinemia a predominio de la indirecta. Se indica fototerapia, Oxigeno, y antibioticoterapia a base de PNC, Amikacina y vancomicina, Se realiza serología para TORCHS la cual reporta negativa y valoración por hematología la cual reporta anomalía de Pelger-Huet. Se presenta este caso para dar a conocer la existencia de esta anomalía como causa de errores frecuenctes al momento de valorar la hematología en procesos infecciosos y no infecciosos, que reportan reacciones leucemoides. Es importante que tanto el médico tratante como el paciente, esten en conocimiento de esta anomalía sanguínea, para valorar de forma adecuada el hemograma en posteriores oportunidades.