ABSTRACT
ABSTRACT In patients with severe respiratory failure, either hypoxemic or hypercapnic, life support with mechanical ventilation alone can be insufficient to meet their needs, especially if one tries to avoid ventilator settings that can cause injury to the lungs. In those patients, extracorporeal membrane oxygenation (ECMO), which is also very effective in removing carbon dioxide from the blood, can provide life support, allowing the application of protective lung ventilation. In this review article, we aim to explore some of the most relevant aspects of using ECMO for respiratory support. We discuss the history of respiratory support using ECMO in adults, as well as the clinical evidence; costs; indications; installation of the equipment; ventilator settings; daily care of the patient and the system; common troubleshooting; weaning; and discontinuation.
RESUMO Em pacientes com insuficiência respiratória grave (hipoxêmica ou hipercápnica), o suporte somente com ventilação mecânica pode ser insuficiente para suas necessidades, especialmente quando se tenta evitar o uso de parâmetros ventilatórios que possam causar danos aos pulmões. Nesses pacientes, extracorporeal membrane oxygenation (ECMO, oxigenação extracorpórea por membrana), que também é muito eficaz na remoção de dióxido de carbono do sangue, pode manter a vida, permitindo o uso de ventilação pulmonar protetora. No presente artigo de revisão, objetivamos explorar alguns dos aspectos mais relevantes do suporte respiratório por ECMO. Discutimos a história do suporte respiratório por ECMO em adultos; evidências clínicas; custos; indicações; instalação do equipamento; parâmetros ventilatórios; cuidado diário do paciente e do sistema; solução de problemas comuns; desmame e descontinuação.
Subject(s)
Humans , Adult , Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome/therapy , Respiratory Insufficiency/therapy , Extracorporeal Membrane Oxygenation/adverse effects , Hypercapnia , Hypoxia , Respiratory Distress Syndrome/diagnostic imaging , Respiratory Distress Syndrome/physiopathology , Respiratory Insufficiency/diagnostic imaging , Respiratory Insufficiency/physiopathology , Respiratory Tract Infections/physiopathology , Respiratory Tract Infections/therapyABSTRACT
RESUMO A tomografia por impedância elétrica torácica constitui ferramenta de monitorização não invasiva, em tempo real, da distribuição regional da ventilação pulmonar. Sua utilização à beira do leito em pacientes com síndrome do desconforto respiratório agudo tem o potencial de auxiliar na condução de manobras de recrutamento alveolar, frequentemente necessárias em casos de hipoxemia refratária. Neste relato de caso, apresentamos os resultados e a interpretação da monitorização da tomografia por impedância elétrica torácica em um paciente com síndrome do desconforto respiratório agudo, durante manobras de recrutamento alveolar, com aplicação transitória de altas pressões alveolares e titulação da pressão positiva ao final da expiração ideal. Adicionalmente, apresentamos uma breve revisão da literatura a respeito do uso de manobras de recrutamento alveolar e monitorização com tomografia por impedância elétrica torácica em pacientes com síndrome do desconforto respiratório agudo.
ABSTRACT Thoracic electrical impedance tomography is a real-time, noninvasive monitoring tool of the regional pulmonary ventilation distribution. Its bedside use in patients with acute respiratory distress syndrome has the potential to aid in alveolar recruitment maneuvers, which are often necessary in cases of refractory hypoxemia. In this case report, we describe the monitoring results and interpretation of thoracic electrical impedance tomography used during alveolar recruitment maneuvers in a patient with acute respiratory distress syndrome, with transient application of high alveolar pressures and optimal positive end-expiratory pressure titration. Furthermore, we provide a brief literature review regarding the use of alveolar recruitment maneuvers and monitoring using thoracic electrical impedance tomography in patients with acute respiratory distress syndrome.
Subject(s)
Humans , Male , Respiratory Distress Syndrome/therapy , Tomography/methods , Electric Impedance , Pulmonary Alveoli/metabolism , Respiratory Distress Syndrome/diagnostic imaging , Positive-Pressure Respiration/methods , Middle AgedABSTRACT
Context: Mechanical ventilation with positive end expiratory pressure (PEEP) is associated with unequal aeration of lungs in acute respiratory distress syndrome (ARDS) patients. Therefore, patients may develop asymmetric atelectasis and postural hypoxemia during lateral positioning. Aims: To validate proposed lung infiltration score (LIS) based on chest x-ray to predict postural hypoxemia and lateralization of skin sores in ARDS patients. Settings and Design: University hospital ICU. Prospective, observational study of consecutive patients. Materials and Methods: Sixteen adult patients of both genders on mechanical ventilation with PEEP for 24 to <48 hours. On chest x-ray, 6 segments were identified on each lung. The proposed LIS points (0- normal; 1- patchy infiltrates; 2- white infiltrates matching heart shadow) were assigned to each segment. Without changing ventilation parameters, supine, left and right lateral positions at 45° tilt were randomly changed. At the end of 20 minutes of ventilation in each position, we observed arterial oxygen saturation, hemodynamic and arterial blood gases. Later, position change protocol (4 hourly) was practiced in ICU, and skin pressure sore grading was noted within a week of ICU stay. Statistical Analysis Used: Nonparametric Bland and Altman correlation analysis, ANOVA and Student t test. Results: Arterial oxygenation (PaO 2 /FiO 2 = 313± 145.6) was significantly (P<0.01) higher in better lung (lower LIS)-down position than supine (PaO 2 /FiO 2 = 199± 70.2) or a better lung-up position (PaO 2 /FiO 2 = 165± 64.8). The positioning-related arterial oxygenation was significant (P< 0.05) at LIS asymmetry ≥3 between two lungs. Conclusions: The LIS mapping on chest x-ray was useful to differentiate between asymmetric lung disease and postural hypoxemia in ICU patients, which predisposed patients to early skin sore changes on higher LIS side.