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BACKGROUND: Protective ventilation seems crucial during early Acute Respiratory Distress Syndrome (ARDS), but the optimal duration of lung protection remains undefined. High driving pressures (ΔP) and excessive patient ventilatory drive may hinder lung recovery, resulting in self-inflicted lung injury. The hidden nature of the ΔP generated by patient effort complicates the situation further. Our study aimed to assess the feasibility of an extended lung protection strategy that includes a stepwise protocol to control the patient ventilatory drive, assessing its impact on lung recovery. METHODS: We conducted a single-center randomized study on patients with moderate/severe COVID-19-ARDS with low respiratory system compliance (CRS < 0.6 (mL/Kg)/cmH2O). The intervention group received a ventilation strategy guided by Electrical Impedance Tomography aimed at minimizing ΔP and patient ventilatory drive. The control group received the ARDSNet low-PEEP strategy. The primary outcome was the modified lung injury score (mLIS), a composite measure that integrated daily measurements of CRS, along with oxygen requirements, oxygenation, and X-rays up to day 28. The mLIS score was also hierarchically adjusted for survival and extubation rates. RESULTS: The study ended prematurely after three consecutive months without patient enrollment, attributed to the pandemic subsiding. The intention-to-treat analysis included 76 patients, with 37 randomized to the intervention group. The average mLIS score up to 28 days was not different between groups (P = 0.95, primary outcome). However, the intervention group showed a faster improvement in the mLIS (1.4 vs. 7.2 days to reach 63% of maximum improvement; P < 0.001), driven by oxygenation and sustained improvement of X-ray (P = 0.001). The intervention group demonstrated a sustained increase in CRS up to day 28 (P = 0.009) and also experienced a shorter time from randomization to room-air breathing (P = 0.02). Survival at 28 days and time until liberation from the ventilator were not different between groups. CONCLUSIONS: The implementation of an individualized PEEP strategy alongside extended lung protection appears viable. Promising secondary outcomes suggested a faster lung recovery, endorsing further examination of this strategy in a larger trial. Clinical trial registration This trial was registered with ClinicalTrials.gov (number NCT04497454) on August 04, 2020.
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BACKGROUND: Protective mechanical ventilation strategies using low tidal volume or high levels of positive end-expiratory pressure (PEEP) improve outcomes for patients who have had surgery. The role of the driving pressure, which is the difference between the plateau pressure and the level of positive end-expiratory pressure is not known. We investigated the association of tidal volume, the level of PEEP, and driving pressure during intraoperative ventilation with the development of postoperative pulmonary complications. METHODS: We did a meta-analysis of individual patient data from randomised controlled trials of protective ventilation during general anesthaesia for surgery published up to July 30, 2015. The main outcome was development of postoperative pulmonary complications (postoperative lung injury, pulmonary infection, or barotrauma). FINDINGS: We included data from 17 randomised controlled trials, including 2250 patients. Multivariate analysis suggested that driving pressure was associated with the development of postoperative pulmonary complications (odds ratio [OR] for one unit increase of driving pressure 1·16, 95% CI 1·13-1·19; p<0·0001), whereas we detected no association for tidal volume (1·05, 0·98-1·13; p=0·179). PEEP did not have a large enough effect in univariate analysis to warrant inclusion in the multivariate analysis. In a mediator analysis, driving pressure was the only significant mediator of the effects of protective ventilation on development of pulmonary complications (p=0·027). In two studies that compared low with high PEEP during low tidal volume ventilation, an increase in the level of PEEP that resulted in an increase in driving pressure was associated with more postoperative pulmonary complications (OR 3·11, 95% CI 1·39-6·96; p=0·006). INTERPRETATION: In patients having surgery, intraoperative high driving pressure and changes in the level of PEEP that result in an increase of driving pressure are associated with more postoperative pulmonary complications. However, a randomised controlled trial comparing ventilation based on driving pressure with usual care is needed to confirm these findings. FUNDING: None.
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Anestesia Geral/efeitos adversos , Pneumopatias/etiologia , Respiração com Pressão Positiva/efeitos adversos , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Anestesia Geral/métodos , Feminino , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Respiração com Pressão Positiva/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Volume de Ventilação PulmonarRESUMO
INTRODUCTION: A recent meta-analysis showed that weaning with SmartCare™ (Dräger, Lübeck, Germany) significantly decreased weaning time in critically ill patients. However, its utility compared with respiratory physiotherapist-protocolized weaning is still a matter of debate. We hypothesized that weaning with SmartCare™ would be as effective as respiratory physiotherapy-driven weaning in critically ill patients. METHODS: Adult critically ill patients mechanically ventilated for more than 24 hours in the adult intensive care unit of the Albert Einstein Hospital, São Paulo, Brazil, were randomly assigned to be weaned either by progressive discontinuation of pressure support ventilation (PSV) with SmartCare™. Demographic data, respiratory function parameters, level of PSV, tidal volume (VT), positive end-expiratory pressure (PEEP), inspired oxygen fraction (FIO2), peripheral oxygen saturation (SpO2), end-tidal carbon dioxide concentration (EtCO2) and airway occlusion pressure at 0.1 second (P0.1) were recorded at the beginning of the weaning process and before extubation. Mechanical ventilation time, weaning duration and rate of extubation failure were compared. RESULTS: Seventy patients were enrolled 35 in each group. There was no difference between the two groups concerning age, sex or diagnosis at study entry. There was no difference in maximal inspiratory pressure, maximal expiratory pressure, forced vital capacity or rapid shallow breathing index at the beginning of the weaning trial. PEEP, VT, FIO2, SpO2, respiratory rate, EtCO2 and P0.1 were similar between the two groups, but PSV was not (median: 8 vs. 10 cmH2O; p =0.007). When the patients were ready for extubation, PSV (8 vs. 5 cmH2O; p =0.015) and PEEP (8 vs. 5 cmH2O; p <0.001) were significantly higher in the respiratory physiotherapy-driven weaning group. Total duration of mechanical ventilation (3.5 [2.0-7.3] days vs. 4.1 [2.7-7.1] days; p =0.467) and extubation failure (2 vs. 2; p =1.00) were similar between the two groups. Weaning duration was shorter in the respiratory physiotherapy-driven weaning group (60 [50-80] minutes vs. 110 [80-130] minutes; p <0.001). CONCLUSION: A respiratory physiotherapy-driven weaning protocol can decrease weaning time compared with an automatic system, as it takes into account individual weaning difficulties. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT02122016 . Date of Registration: 27 August 2013.
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Extubação/métodos , Estado Terminal/terapia , Sistemas de Apoio a Decisões Clínicas/instrumentação , Unidades de Terapia Intensiva , Modalidades de Fisioterapia/normas , Respiração Artificial , Desmame do Respirador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Extubação/instrumentação , Extubação/normas , Brasil , Sistemas de Apoio a Decisões Clínicas/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desmame do Respirador/instrumentação , Desmame do Respirador/normasAssuntos
Causas de Morte , Mortalidade Hospitalar , Oxigênio/sangue , Síndrome do Desconforto Respiratório/classificação , Adulto , Gasometria , Brasil/epidemiologia , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Estudos Multicêntricos como Assunto , Países Baixos/epidemiologia , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Respiração com Pressão Positiva , Prognóstico , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/mortalidade , Índice de Gravidade de Doença , Estudos de Validação como AssuntoRESUMO
OBJECTIVES: Evaluation of prevalence and outcomes of acute lung injury in a large cohort of critically ill patients in Brazil and comparison of predictive receiver operating characteristic curve mortality of American European Consensus conference definition with new Berlin definition of acute respiratory distress syndrome. DESIGN: A 15-month prospective, multicenter, observational study. SETTING: Fourteen medical ICUs in Espirito Santo, a state of Brazil. PATIENTS: Mechanically ventilated patients who fulfilled American European Consensus conference criteria of acute lung injury or Berlin definition of acute respiratory distress syndrome. INTERVENTIONS: Clinical and respiratory data were collected for 7 consecutive days and on the 14 and 28 days. Twenty-eight day mortality, hospital mortality, and predictive receiver operating characteristic curve mortality were calculated. MEASUREMENTS AND MAIN RESULTS: Of 7,133 patients, 130 patients (1.8%) fulfilled criteria for acute lung injury (American European Consensus conference) or acute respiratory distress syndrome (Berlin definition). Median time for diagnosis was 2 days (interquartile range, 0-3 d). Main risk factors were pneumonia (35.3%) and nonpulmonary sepsis (31.5%). Mean age was 44.2 ± 15.9 years, and 61.5% were men. Mean Acute Physiology and Chronic Health Evaluation II score was 20.7 ± 7.9. Mean PaO2/FIO2 was 206 ± 61.5, significantly lower in nonsurvivors on day 7 (p = 0.003). Mean mechanical ventilation time was 21 ± 15 days. Length of ICU stay was 26.4 ± 18.7 days. Twenty-eight-day mortality was 38.5% (95% CI, 30.1-46.8); hospital mortality was 49.2% (95% CI, 40.6-57.8). Predictive 28-day mortality area under the receiver operating characteristic curve for American European Consensus conference definition was 0.5625 (95% CI, 0.4783-0.6467) and for the Berlin definition 0.5664 (95% CI, 0.4759-0.6568; p = 0.9510). CONCLUSIONS: In our population, prevalence of acute lung injury was low, most cases were diagnosed 2 days after ICU admission, and Berlin definition was not different from American European Consensus conference definition in predicting mortality. There are still several problems with the global epidemiology, definition, and mortality predictive indices that should be added to the classification of this still lethal syndrome to improve its predictive mortality power in the future.
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Lesão Pulmonar Aguda/epidemiologia , Lesão Pulmonar Aguda/terapia , Mortalidade Hospitalar/tendências , Unidades de Terapia Intensiva , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/terapia , APACHE , Lesão Pulmonar Aguda/diagnóstico , Adolescente , Adulto , Idoso , Análise de Variância , Brasil , Estado Terminal/mortalidade , Estado Terminal/terapia , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Estimativa de Kaplan-Meier , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/epidemiologia , Testes de Função Respiratória , Medição de Risco , Estatísticas não Paramétricas , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
PURPOSE OF REVIEW: To analyze recently published articles in the medical literature that studied distinct aspects of adult patients with acute respiratory distress syndrome (ARDS) after the new Berlin definition introduced in 2012. RECENT FINDINGS: The degree of ARDS severity according to this new classification correlated well with extravascular lung water index, pulmonary vascular permeability index and the finding of diffuse alveolar damage on autopsy. The new possibility of bedside echocardiographic evaluation of biventricular cardiac function is indicating the necessity of including a subgroup of severity of patients with right ventricular dysfunction. High-resolution CT evaluation showed that signs of pulmonary fibroproliferation in early ARDS predict increased ventilator dependency, multiple organ failure and mortality. The median development of ARDS 1 or 2 days after hospital admission emphasizes the need for ARDS intrahospital prevention, especially protective ventilation in non-ARDS patients. The better outcome with the use of prone position in patients with PaO2/FIO2 below 150 recently observed questioned the Berlin definition thresholds to decide the future best treatment strategies according to the proposed degree of severity of the syndrome. SUMMARY: The impact of the Berlin definition of ARDS on the incidence, better treatment stratification and mortality ratio of ARDS is still to be determined.
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Água Extravascular Pulmonar , Síndrome do Desconforto Respiratório/classificação , Lesão Pulmonar Induzida por Ventilação Mecânica/diagnóstico por imagem , Disfunção Ventricular Direita/complicações , Adulto , Progressão da Doença , Água Extravascular Pulmonar/diagnóstico por imagem , Feminino , Humanos , Masculino , Prognóstico , Decúbito Ventral , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Síndrome do Desconforto Respiratório/mortalidade , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Ultrassonografia , Lesão Pulmonar Induzida por Ventilação Mecânica/mortalidade , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/mortalidadeRESUMO
Neste capitulo, discutiremos o que são as doenças pulmonares fibrosantes, que se caracterizam por um distúrbio pulmonar restritivo progressivo associado a uma diminuição da difusão da membrana alvéolo-capilar pulmonar, expressando-se clinicamente por dispneia e hipoxemia cada vez mais intensas. A doença mais representativa desse grupo é a fibrose pulmonar idiopática, mas a pneumonia intersticial não específica, as doenças intersticiais associadas a doenças do colágeno, sarcoidose, pneumonia de hipersensibilidade crônica e asbestose também podem cursar de maneira fibrogênica progressiva. O reconhecimento de cada uma dessas doenças e da possibilidade de o padrão histológico de pneumonia intersticial usual estar ocorrendo é de fundamental importância para a orientação dos pacientes sobre a pior evolução temporal e a pior resposta ao tratamento medicamentoso. Em pacientes com menos de 65 anos, o transplante pulmonar pode ser uma opção terapêutica.
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Humanos , Masculino , Feminino , Doenças Pulmonares Intersticiais , Transplante de Pulmão , Fibrose Pulmonar , Doenças Respiratórias , TerapêuticaRESUMO
INTRODUCTION: The benefits of higher positive end expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) have been modest, but few studies have fully tested the "open-lung hypothesis". This hypothesis states that most of the collapsed lung tissue observed in ARDS can be reversed at an acceptable clinical cost, potentially resulting in better lung protection, but requiring more intensive maneuvers. The short-/middle-term efficacy of a maximum recruitment strategy (MRS) was recently described in a small physiological study. The present study extends those results, describing a case-series of non-selected patients with early, severe ARDS submitted to MRS and followed until hospital discharge or death. METHODS: MRS guided by thoracic computed tomography (CT) included two parts: a recruitment phase to calculate opening pressures (incremental steps under pressure-controlled ventilation up to maximum inspiratory pressures of 60 cmH2O, at constant driving-pressures of 15 cmH2O); and a PEEP titration phase (decremental PEEP steps from 25 to 10 cmH2O) used to estimate the minimum PEEP to keep lungs open. During all steps, we calculated the size of the non-aerated (-100 to +100 HU) compartment and the recruitability of the lungs (the percent mass of collapsed tissue re-aerated from baseline to maximum PEEP). RESULTS: A total of 51 severe ARDS patients, with a mean age of 50.7 years (84% primary ARDS) was studied. The opening plateau-pressure was 59.6 (±5.9 cmH2O), and the mean PEEP titrated after MRS was 24.6 (±2.9 cmH2O). Mean PaO2/FiO2 ratio increased from 125 (±43) to 300 (±103; P<0.0001) after MRS and was sustained above 300 throughout seven days. Non-aerated parenchyma decreased significantly from 53.6% (interquartile range (IQR): 42.5 to 62.4) to 12.7% (IQR: 4.9 to 24.2) (P<0.0001) after MRS. The potentially recruitable lung was estimated at 45% (IQR: 25 to 53). We did not observe major barotrauma or significant clinical complications associated with the maneuver. CONCLUSIONS: MRS could efficiently reverse hypoxemia and most of the collapsed lung tissue during the course of ARDS, compatible with a high lung recruitability in non-selected patients with early, severe ARDS. This strategy should be tested in a prospective randomized clinical trial.
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Complacência Pulmonar/fisiologia , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Síndrome do Desconforto Respiratório/fisiopatologia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Respiração com Pressão Positiva/métodos , Estudos Prospectivos , Síndrome do Desconforto Respiratório/diagnóstico , Tomografia Computadorizada por Raios X/métodosRESUMO
As vasculites antineutrophil cytoplasmic antibody (ANCA, anticorpo anticitoplasma de neutrófilos) associadas (VAAs) são caracterizadas por uma inflamação sistêmica das artérias de pequeno e médio calibre (especialmente no trato respiratório superior e inferior, e nos rins). As VAAs compreendem a granulomatose de Wegener (agora chamada de granulomatose com poliangeíte), poliangeíte microscópica, VAA limitada ao rim e a síndrome de Churg-Strauss. Neste artigo, discutiremos as fases de tratamento dessas vasculites, como fase de indução (com ciclofosfamida ou rituximab) e fase de manutenção (com azatioprina, metotrexato ou rituximab). Além disso, discutiremos como manusear os casos refratários à ciclofosfamida.
In its various forms, antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is characterized by a systemic inflammation of the small and medium-sized arteries (especially in the upper and lower respiratory tracts, as well as in the kidneys). The forms of AAV comprise Wegener's granulomatosis (now called granulomatosis with polyangiitis), microscopic polyangiitis, renal AAV, and Churg-Strauss syndrome. In this paper, we discuss the phases of AAV treatment, including the induction phase (with cyclophosphamide or rituximab) and the maintenance phase (with azathioprine, methotrexate, or rituximab). We also discuss how to handle patients who are refractory to cyclophosphamide.
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Humanos , Imunossupressores/uso terapêutico , Poliangiite Microscópica/tratamento farmacológico , Granulomatose com Poliangiite/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Anticorpos Monoclonais Murinos/uso terapêutico , Azatioprina/uso terapêutico , Ciclofosfamida/uso terapêutico , Quimioterapia de Indução/métodos , Metotrexato/uso terapêutico , Fatores de TempoRESUMO
OBJECTIVES: To assess whether the combination of daily evaluation and use of a spontaneous breathing test could shorten the duration of mechanical ventilation as compared with weaning based on our standard of care. Secondary outcome measures included extubation failure rate and the need for noninvasive ventilation. DESIGN: A prospective, randomized controlled trial. SETTING: Two pediatric intensive care units at university hospitals in Brazil. PATIENTS: The trial involved children between 28 days and 15 yrs of age who were receiving mechanical ventilation for at least 24 hrs. INTERVENTIONS: Patients were randomly assigned to one of two weaning protocols. In the test group, the children underwent a daily evaluation to check readiness for weaning with a spontaneous breathing test with 10 cm H2O pressure support and a positive end-expiratory pressure of 5 cm H2O for 2 hrs. The spontaneous breathing test was repeated the next day for children who failed it. In the control group, weaning was performed according to standard care procedures. MEASUREMENTS AND MAIN RESULTS: A total of 294 eligible children were randomized, with 155 to the test group and 139 to the control group. The time to extubation was shorter in the test group, where the median mechanical ventilation duration was 3.5 days (95% confidence interval, 3.0 to 4.0) as compared to 4.7 days (95% confidence interval, 4.1 to 5.3) in the control group (p = .0127). This significant reduction in the mechanical ventilation duration for the intervention group was not associated with increased rates of extubation failure or noninvasive ventilation. It represents a 30% reduction in the risk of remaining on mechanical ventilation (hazard ratio: 0.70). CONCLUSIONS: A daily evaluation to check readiness for weaning combined with a spontaneous breathing test reduced the mechanical ventilation duration for children on mechanical ventilation for >24 hrs, without increasing the extubation failure rate or the need for noninvasive ventilation.
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Unidades de Terapia Intensiva Pediátrica , Desmame do Respirador/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Hospitais Universitários , Humanos , Lactente , Masculino , Estudos Prospectivos , Testes de Função RespiratóriaRESUMO
BACKGROUND: The combination of high PEEP and low tidal volume (V(T)) decreases some risks of mechanical ventilation, including pulmonary overdistention, damage due to cyclic opening and closing of the alveoli, and inflammatory responses that can lead to multiple-organ dysfunction. We hypothesized that high V(T) and high PEEP induce mesenteric microcirculatory disturbances and that those disturbances would be attenuated by pentoxifylline, which is anti-inflammatory. METHODS: We anesthetized (isoflurane 1.5%), tracheostomized, and mechanically ventilated 57 male Wistar rats with PEEP of 10 cm H(2)O and F(IO(2)) of 0.21 for 2 hours. One group received low V(T) (7 mL/kg), another group received high V(T) (10 mL/kg), and a third group received high V(T) plus pentoxifylline (25 mg/kg). We measured mean arterial pressure, respiratory mechanics, mesenteric blood flow, and leukocyte-endothelial interactions. RESULTS: The mean arterial pressure was similar among the groups at baseline (108 mm Hg [IQR 94-118 mm Hg]) and after 2 hours of mechanical ventilation (104 mm Hg [IQR 90-114 mm Hg]). Mesenteric blood flow was also similar between the groups: low V(T) 15.1 mL/min (IQR 12.4-17.7 mL/min), high V(T) 11.3 mL/min (IQR 8.6-13.8 mL/min), high-V(T)/pentoxifylline 12.4 mL/min (10.8-13.7 mL/min). Peak airway pressure after 2 hours was lower (P = .03) in the low-V(T) group (10.4 cm H(2)O [IQR 10.2-10.4 cm H(2)O]) than in the high-V(T) group (12.6 cm H(2)O [10.2-14.9 cm H(2)O]) or the high-V(T)/pentoxifylline group (12.8 cm H(2)O [10.7-16.0 cm H(2)O]). There were fewer adherent leukocytes (P = .005) and fewer migrated leukocytes (P = .002) in the low-V(T) group (5 cells/100 µm length [IQR 4-7 cells/100 µm length] and 1 cell/5,000 µm(2) [IQR 1-2 cells/5,000 µm(2)], respectively) and the high-V(T)/pentoxifylline group (5 cells/100 µm length [IQR 3-10 cells/100 µm length] and 1 cell/5,000 µm(2) [IQR 1-3 cells/5,000 µm(2)], respectively) than in the high-V(T) group (14 cells/100 µm length [IQR 11-16 cells/100 µm length] and 9 cells/5,000 µm(2) [IQR 8-12 cells/5,000 µm(2)], respectively). CONCLUSIONS: Low V(T) with high PEEP was lung-protective, and early pentoxifylline reduced the inflammatory response to high V(T) with high PEEP (and presumed lung overdistention) during mechanical ventilation.
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Intestinos/irrigação sanguínea , Pentoxifilina/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Circulação Esplâncnica/efeitos dos fármacos , Circulação Esplâncnica/fisiologia , Volume de Ventilação Pulmonar , Animais , Endotélio Vascular/metabolismo , Hemodinâmica , Leucócitos/metabolismo , Masculino , Microcirculação , Microscopia/métodos , Infiltração de Neutrófilos/fisiologia , Respiração com Pressão Positiva , Ratos , Ratos Wistar , Respiração ArtificialRESUMO
A definição da síndrome do desconforto respiratório agudo (SDRA), simplificada pela Conferência Americana e Europeia de Consenso em SDRA de 1998, inclui a presença de infiltrado pulmonar bilateral, relação pressão parcial arterial de oxigênio/fração inspirada de oxigênio < 200 mmHg e pressão capilar pulmonar < 18 mmHg ou ausência de sinais de insuficiência cardíaca esquerda. Atualmente, o entendimento mais complexo da SDRA inclui sua análise mais detalhada pela tomografia de tórax e por outros métodos de imagem. A utilização de marcadores genéticos e biomarcadores plasmáticos e no lavado broncoalveolar antecipará o diagnóstico e o prognóstico de SDRA. A introdução de sistemas automáticos de diagnóstico e a análise de fatores de risco e de fatores prognósticos associados à SDRA ajudarão no entendimento mais aprofundado da doença para seu melhor tratamento e diminuição de suas taxas de mortalidade.
The definition of acute respiratory distress syndrome (ARDS) was simplified at the 1998 American-European Consensus Conference of 1998 and now includes the following: bilateral pulmonary infiltrates; arterial oxygen tension/fraction of inspired oxygen < 200 mmHg; and pulmonary capillary wedge pressure < 18 mmHg or no signs of left heart failure. Recently, tomography and other imaging methods have allowed the chest to be analyzed in greater detail, thereby leading to a more complex understanding of ARDS. The use of genetic markers and biomarkers in plasma and bronchoalveolar lavage could lead to earlier ARDS diagnosis, thereby improving prognosis. The introduction of automatic diagnostic screening, together with the analysis of risk factors and prognostic factors associated with the syndrome, will deepen the understanding of ARDS, improving treatment and potentially reducing the associated mortality rates.
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Humanos , Masculino , Feminino , Adulto , Síndrome do Desconforto Respiratório/classificação , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/prevenção & controleRESUMO
In its various forms, antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is characterized by a systemic inflammation of the small and medium-sized arteries (especially in the upper and lower respiratory tracts, as well as in the kidneys). The forms of AAV comprise Wegener's granulomatosis (now called granulomatosis with polyangiitis), microscopic polyangiitis, renal AAV, and Churg-Strauss syndrome. In this paper, we discuss the phases of AAV treatment, including the induction phase (with cyclophosphamide or rituximab) and the maintenance phase (with azathioprine, methotrexate, or rituximab). We also discuss how to handle patients who are refractory to cyclophosphamide.
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Granulomatose com Poliangiite/tratamento farmacológico , Imunossupressores/uso terapêutico , Poliangiite Microscópica/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Anticorpos Monoclonais Murinos/uso terapêutico , Azatioprina/uso terapêutico , Ciclofosfamida/uso terapêutico , Humanos , Quimioterapia de Indução/métodos , Metotrexato/uso terapêutico , Rituximab , Fatores de TempoRESUMO
A tomografia computadorizada (TC) é uma excelente ferramenta diagnóstica de fundamental importância para o cuidado de pacientes graves nas unidades de terapia intensiva e que revolucionou o entendimento do comportamento pulmonar na lesão pulmonar aguda/síndrome do desconforto respiratório agudo (SDRA). O emprego da TC de tórax como ferramenta de ajuste da ventilação mecânica em pacientes com SDRA pode conferir maior proteção à ocorrência dos vários mecanismos de lesão induzida por ventilação mecânica e talvez até melhorar o desfecho clínico. O objetivo do presente artigo foi descrever a importância da TC de tórax na avaliação de pacientes com SDRA, com detalhamento dos mecanismos envolvidos no colapso pulmonar e na individualização da estratégia ventilatória por meio da estratégia de recrutamento máximo.
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Humanos , Masculino , Feminino , Respiração Artificial , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Tomografia Computadorizada por Raios X , Diagnóstico por Imagem , Pneumopatias , Transtornos Respiratórios , Terapia RespiratóriaRESUMO
O presente artigo discute a avaliação dos índices de desmame da ventilação mecânica, suas aplicabilidades, limitações, acurácia e recomendações. Embora o teste de respiração espontânea seja recomendado antes do desmame e a impressão clínica seja importante, ambos não são suficientes para predizer o resultado do desmame. A maioria dos índices de desmame não é acurada; no entanto, ao menos cinco devem ser considerados para avaliar o seu prognóstico. O índice de desmame mais utilizado é a relação frequência respiratória/volume corrente, também conhecido como índice de respiração rápida e superficial. Os demais índices atualmente recomendados são frequência respiratória, pressão inspiratória máxima, volume corrente e capacidade vital. Em âmbito nacional, temos o índice integrativo de desmame, que tem mostrado alta acurácia em populações heterogêneas. As principais limitações dos índices de desmame são populações específicas, diferentes pontos de cortes utilizadose variações nas formas de mensuração. Como a impressão clínica e o teste de respiração espontânea não são 100% acurados, os índices de desmame podem ser úteis, principalmente em situações de difíceis decisões para a descontinuação da ventilação mecânica.
Assuntos
Humanos , Masculino , Feminino , Unidades de Terapia Intensiva , Respiração Artificial , Desmame do Respirador , Terapia RespiratóriaRESUMO
Acreditávamos que a assincronia paciente-ventilador ocorresse exclusivamente em modos mandatórios de ventilação. Na última década, muitos trabalhos vêm mostrando que assincronia também ocorre nos modos espontâneos, como pressão de suporte. Isso porque os modos ventilatórios convencionais são estáticos, enquanto o paciente é um ser dinâmico que está em constante adaptação. O paciente apresenta demanda ventilatória variável, realizando contrações diafragmáticas de amplitudes diferentes e apresentando alterações constantes em sua mecânica respiratória, como complacência, elastância, resistência e pressão expiratória final positiva intrínseca ao longo do tempo, o que torna o ajuste na ventilação um grandedesafio para o profissional. Realizar ajustes abaixo ou acima da necessidade do paciente gera assincronia com implicações clínicas importantes que podem prejudicar a evolução no desmame, em especial o ajuste excessivo, que é de difícil percepção clínica e que pode provocar atrofia diafragmática e lesão muscular respiratória, que dificultará a extubação do paciente. Isso justifica a busca por novas tecnologias que permitam uma maior interação entre o paciente e o ventilador de maneira que o ventilador seja capaz de se adaptar ao dinamismo do paciente. A ventilação assistida proporcional plus visa atingir esse objetivo; para tanto devemos conhecer seu funcionamento e realizar uma atualização sobre a literatura existente.
Assuntos
Humanos , Masculino , Feminino , Respiração Artificial , Mecânica Respiratória , Desmame do Respirador , Fenômenos Fisiológicos Respiratórios , Terapia RespiratóriaRESUMO
INTRODUCTION: Indexes predicting weaning outcome are frequently inaccurate. We developed a new integrative weaning index aimed at improving the accuracy of the traditional indexes. METHODS: Three hundred and thirty-one patients mechanically-ventilated for more than 24 hours were evaluated. Initially, the threshold values of each index that best discriminate between a successful and an unsuccessful weaning outcome were determined in 115 patients. In the second phase, the predictive performance of these values was tested prospectively in the other 216 patients. Frequency/tidal volume ratio (f/Vt ratio), tidal volume (Vt), tracheal airway occlusion pressure 0.1 s (P 0.1), the product of P 0.1 and f/Vt (P 0.1 x f/Vt), respiratory rate (f), static compliance of the respiratory system (Cst,rs), ratio of arterial oxygen tension to fraction of inspired oxygen (PaO2/FiO2 ratio) and the new integrative weaning index IWI (Cst,rs x arterial oxygen saturation/f/Vt ratio) were evaluated in all patients. The readiness for weaning and the decision to return to mechanical ventilation was made by the physician in charge, based on the signs of poor tolerance. The receiver operating characteristic (ROC) curves were calculated in order to evaluate the predictive performance of each index. The Bayes' theorem was used to assess the probability of each test of predicting weaning. RESULTS: In the prospective-validation set, successful weaning was observed in 183 patients (84.7%) and weaning failure in 33 (15.27%). IWI presented the highest accuracy, with the area under the ROC curves larger than that under the curves for the f/Vt ratio (0.96 x 0.85 respectively; P = 0.003), and also larger than that under the curves for the other indexes. IWI presented a higher probability of successful weaning when the test was positive (0.99) and a lower probability when the test was negative (0.14). Measurement of Cst,rs during the weaning process was considered one of the study limitations. CONCLUSIONS: IWI was the best predictive performance index of weaning outcome and can be used in the intensive care unit setting. TRIAL REGISTRATION: controlled-trials.com ISRCTN92117906.
Assuntos
Desmame do Respirador/métodos , Idoso , Idoso de 80 Anos ou mais , Teorema de Bayes , Biomarcadores/análise , Difusão de Inovações , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Fenômenos Fisiológicos RespiratóriosRESUMO
PURPOSE: The objective of this study is to evaluate the predictive performance of maximal inspiratory pressure (Pimax), airway occlusion pressure (P 0.1), and its ratio (P 0.1/Pimax) in the weaning outcome. MATERIALS AND METHODS: Seventy patients on mechanical ventilation for more than 24 hours, who fulfilled weaning criteria, were prospectively evaluated. Pimax less than -25 cm H(2)O, P 0.1 less than 4.2 cm H(2)O, and P 0.1/Pimax less than 0.14 were evaluated in all patients before spontaneous breathing trials. The receiver operating characteristic (ROC) curve was calculated to evaluate the predictive performance of each index. RESULTS: Pimax presented the area under the ROC curves smaller than those for P 0.1 and P 0.1/Pimax (0.52 x 0.76 and 0.52 x 0.78; P = .004 and P = .0006, respectively), being the criteria of worst performance. P 0.1/Pimax presented excellent predictive performance in weaned patients, with sensitivity of 98.08, but with the area under the ROC curves only slightly larger than those for P 0.1 (0.78 x 0.76, respectively; P = .69). CONCLUSION: In our study, P 0.1 and P 0.1/Pimax ratio were moderately accurate, whereas Pimax was less accurate in predicting the weaning outcome.
Assuntos
Obstrução das Vias Respiratórias/fisiopatologia , Inalação/fisiologia , Desmame do Respirador , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Capacidade Inspiratória/fisiologia , Masculino , Pessoa de Meia-IdadeRESUMO
INTRODUCTION: Reduction of automatic pressure support based on a target respiratory frequency or mandatory rate ventilation (MRV) is available in the Taema-Horus ventilator for the weaning process in the intensive care unit (ICU) setting. We hypothesised that MRV is as effective as manual weaning in post-operative ICU patients. METHODS: There were 106 patients selected in the post-operative period in a prospective, randomised, controlled protocol. When the patients arrived at the ICU after surgery, they were randomly assigned to either: traditional weaning, consisting of the manual reduction of pressure support every 30 minutes, keeping the respiratory rate/tidal volume (RR/TV) below 80 L until 5 to 7 cmH2O of pressure support ventilation (PSV); or automatic weaning, referring to MRV set with a respiratory frequency target of 15 breaths per minute (the ventilator automatically decreased the PSV level by 1 cmH2O every four respiratory cycles, if the patient's RR was less than 15 per minute). The primary endpoint of the study was the duration of the weaning process. Secondary endpoints were levels of pressure support, RR, TV (mL), RR/TV, positive end expiratory pressure levels, FiO2 and SpO2 required during the weaning process, the need for reintubation and the need for non-invasive ventilation in the 48 hours after extubation. RESULTS: In the intention to treat analysis there were no statistically significant differences between the 53 patients selected for each group regarding gender (p = 0.541), age (p = 0.585) and type of surgery (p = 0.172). Nineteen patients presented complications during the trial (4 in the PSV manual group and 15 in the MRV automatic group, p < 0.05). Nine patients in the automatic group did not adapt to the MRV mode. The mean +/- sd (standard deviation) duration of the weaning process was 221 +/- 192 for the manual group, and 271 +/- 369 minutes for the automatic group (p = 0.375). PSV levels were significantly higher in MRV compared with that of the PSV manual reduction (p < 0.05). Reintubation was not required in either group. Non-invasive ventilation was necessary for two patients, in the manual group after cardiac surgery (p = 0.51). CONCLUSIONS: The duration of the automatic reduction of pressure support was similar to the manual one in the post-operative period in the ICU, but presented more complications, especially no adaptation to the MRV algorithm. TRIAL REGISTRATION NUMBER: ISRCTN37456640.
Assuntos
Respiração com Pressão Positiva/métodos , Cuidados Pós-Operatórios/métodos , Desmame do Respirador/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Respiração com Pressão Positiva/instrumentação , Cuidados Pós-Operatórios/instrumentação , Estudos Prospectivos , Volume de Ventilação Pulmonar/fisiologia , Desmame do Respirador/instrumentaçãoRESUMO
RATIONALE: The hypothesis that lung collapse is detrimental during the acute respiratory distress syndrome is still debatable. One of the difficulties is the lack of an efficient maneuver to minimize it. OBJECTIVES: To test if a bedside recruitment strategy, capable of reversing hypoxemia and collapse in > 95% of lung units, is clinically applicable in early acute respiratory distress syndrome. METHODS: Prospective assessment of a stepwise maximum-recruitment strategy using multislice computed tomography and continuous blood-gas hemodynamic monitoring. MEASUREMENTS AND MAIN RESULTS: Twenty-six patients received sequential increments in inspiratory airway pressures, in 5 cm H(2)O steps, until the detection of Pa(O(2)) + Pa(CO(2)) >or= 400 mm Hg. Whenever this primary target was not met, despite inspiratory pressures reaching 60 cm H(2)O, the maneuver was considered incomplete. If there was hemodynamic deterioration or barotrauma, the maneuver was to be interrupted. Late assessment of recruitment efficacy was performed by computed tomography (9 patients) or by online continuous monitoring in the intensive care unit (15 patients) up to 6 h. It was possible to open the lung and to keep the lung open in the majority (24/26) of patients, at the expense of transient hemodynamic effects and hypercapnia but without major clinical consequences. No barotrauma directly associated with the maneuver was detected. There was a strong and inverse relationship between arterial oxygenation and percentage of collapsed lung mass (R = - 0.91; p < 0.0001). CONCLUSIONS: It is often possible to reverse hypoxemia and fully recruit the lung in early acute respiratory distress syndrome. Due to transient side effects, the required maneuver still awaits further evaluation before routine clinical application.