Emilia Nozawa

Benefits of non-invasive ventilation after extubation in the postoperative period of heart surgery.

OBJECTIVE to show the benefits of the use of non-invasive positive pressure ventilation (NPPV) in the process of weaning from mechanical ventilation in the immediate postoperative period of heart surgery. METHODS A prospective, randomized and controlled study was performed involving 100 consecutive patients submitted to coronary artery bypass grafting or valve surgery. The subjects were admitted into the Intensive Care Unit (ICU) under mechanical ventilation and randomized in a study group (n=50), which used NPPV with bilevel pressure for 30 minutes after extubation, and a control group (n=50) which only used a nasal O2 catheter. Anthropometric variables and the times of the intra-operative periods corresponding to anesthesia, surgery and cardiopulmonary bypass, as well as the time required for weaning from invasive mechanical ventilation were analysed. The arterial blood gases and hemodynamic variables were also assessed before and after extubation. RESULTS The evolution was similar for the control and study groups without statistically significant differences of the variables analyzed except for the PaO2. On comparing the groups, the PaO2 improved significantly (p = 0.0009) with the use of NPPV for 30 minutes after extubation, but there was no statistically significant difference in the PaCO2 (p = 0.557). CONCLUSION The use of NPPV for 30 minutes after extubation improved oxygenation in the immediate postoperative period of heart surgery.OBJETIVO: Demonstrar os beneficios da utilizacao da ventilacao nao-invasiva (VNI) no processo de interrupcao da ventilacao mecânica, no pos-operatorio de cirurgia cardiaca. METODOS: Estudo prospectivo, randomizado e controlado, com 100 pacientes submetidos a cirurgia de revascularizacao do miocardio ou cirurgia valvar. Os pacientes foram admitidos na Unidade de Terapia Intensiva (UTI), sob ventilacao mecânica e randomizados posteriormente em grupo estudo (n= 50) que utilizou VNI com dois niveis pressoricos apos a extubacao por 30 minutos, e grupo controle (n= 50) que fez uso apenas de cateter nasal de O2. Foram analisadas as variaveis antropometricas, os tempos correspondentes a anestesia, cirurgia e circulacao extracorporea, bem como o tempo necessario para a supressao da ventilacao mecânica invasiva. As variaveis gasometricas e hemodinâmicas tambem foram avaliadas antes e apos a extubacao. RESULTADOS: Os grupos controle e estudo evoluiram de forma semelhante e nao apresentaram diferenca estatisticamente significante na analise das variaveis, exceto para a PaO2. A utilizacao da VNI por 30 minutos apos a extubacao promoveu melhora na PaO2 quando comparados os grupos, com p= 0,0009, mas nao apresentou diferenca estatisticamente significante na PaCO2 (p=0,557). CONCLUSAO: O uso da VNI por 30 minutos apos extubacao produziu melhora na oxigenacao do pacientes em posoperatorio imediato de cirurgia cardiaca.

Perfil de fisioterapeutas brasileiros que atuam em unidades de terapia intensiva

Este estudo visou investigar o perfil dos fisioterapeutas que atuam nas unidades de terapia intensiva (UTIs) no Brasil, focalizando a direcao do servico, tecnicas fisioterapeuticas empregadas e nivel de autonomia em relacao a ventilacao mecânica invasiva e nao-invasiva. Questionarios foram enviados aos chefes dos servicos de fisioterapia de 1.192 hospitais registrados na Associacao Medica de Terapia Intensiva, com retorno de 461 (39%) UTIs. Em 88% destas, os servicos sao chefiados por fisioterapeutas; em 78%, compostos por ate oito fisioterapeutas; 44,4% dos fisioterapeutas trabalham em regime de 30 horas semanais e 46,1% tem contrato de trabalho. Ha assistencia fisioterapeutica durante 24 horas em 33,6% das UTIs; 88% delas mantem assistencia nos finais de semana. Quanto as tecnicas fisioterapeuticas, todos realizam mobilizacao, posicionamento e aspiracao; 91,5% atuam na ventilacao nao-invasiva, sendo que 43% trabalham com total autonomia. Em relacao a ventilacao mecânica invasiva, 80% realizam extubacao; 79,2% realizam regulagem e desmame do ventilador; entretanto, so 22% tem total autonomia (78% necessitam de protocolo ou opiniao da equipe medica). Os fisioterapeutas brasileiros atuam, em sua maioria, em instituicoes privadas e assistenciais, cujos servicos sao chefiados por fisioterapeutas. Tem relativa autonomia quanto as tecnicas fisioterapeuticas e o manuseio da ventilacao mecânica nao-invasiva mas, no caso da invasiva, atuam sob diretiva da equipe medica.

Contrast Echocardiography Can Save Nondiagnostic Exams in Mechanically Ventilated Patients

Patients in an intensive care unit (ICU) under mechanical ventilation (MV) are very difficult to image by transthoracic echocardiography, diminishing the beneficial information that could be obtained by this noninvasive approach. The objective of this study is to assess whether the addition of a contrast agent to fundamental imaging (FI) can improve or change the initial diagnosis in cardiac postoperative patients under mechanical ventilation by enhancing endocardial border delineation and Doppler flow signal. Thirty mechanically ventilated post–cardiac surgery patients (20 men, mean age 61 ± 13 years) were evaluated with FI before and after intravenous injection of contrast. Left ventricular endocardial border delineation score index (EBDSI), estimated left ventricular ejection fraction (LVEF), and color and spectral Doppler were analyzed. The use of contrast resulted in a significant increase in the number of well‐delineated segments, with a salvage rate of 77% of nondiagnostic studies. EBDSI was 1.62 ± 0.61, before contrast, increasing to 2.05 ± 0.53 after it (P < 0.001). There was a change in the LVEF estimation in 5 exams, and a new wall motion abnormality was detected in other 4 exams, after the use of contrast. Moreover, a significant change was observed in the quantification of mitral regurgitation in 5 patients, in the aortic transvalvular peak gradient in 1 patient, and measurement of tricuspid regurgitation peak flow velocity in 8 patients. It is concluded that in cardiac postoperative patients under mechanical ventilation, intravenous injection of a contrast agent using FI resulted in a high salvage rate of studies and changed the initial diagnosis in a significant number of patients.

Aplicação da ventilação não-invasiva em insuficiência respiratória aguda após cirurgia cardiovascular

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% of patients in the ventilator group, 57.9% in the two-pressure levels group, and 47.3% 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.

High levels of B-type natriuretic peptide predict weaning failure from mechanical ventilation in adult patients after cardiac surgery

OBJECTIVE: The failure to wean from mechanical ventilation is related to worse outcomes after cardiac surgery. The aim of this study was to evaluate whether the serum level of B-type natriuretic peptide is a predictor of weaning failure from mechanical ventilation after cardiac surgery. METHODS: We conducted a prospective, observational cohort study of 101 patients who underwent on-pump coronary artery bypass grafting. B-type natriuretic peptide was measured postoperatively after intensive care unit admission and at the end of a 60-min spontaneous breathing test. The demographic data, hemodynamic and respiratory parameters, fluid balance, need for vasopressor or inotropic support, and length of the intensive care unit and hospital stays were recorded. Weaning failure was considered as either the inability to sustain spontaneous breathing after 60 min or the need for reintubation within 48 h. RESULTS: Of the 101 patients studied, 12 patients failed the weaning trial. There were no differences between the groups in the baseline or intraoperative characteristics, including left ventricular function, EuroSCORE and lengths of the cardiac procedure and cardiopulmonary bypass. The B-type natriuretic peptide levels were significantly higher at intensive care unit admission and at the end of the breathing test in the patients with weaning failure compared with the patients who were successfully weaned. In a multivariate model, a high B-type natriuretic peptide level at the end of a spontaneous breathing trial was the only independent predictor of weaning failure from mechanical ventilation. CONCLUSIONS: A high B-type natriuretic peptide level is a predictive factor for the failure to wean from mechanical ventilation after cardiac surgery. These findings suggest that optimizing ventricular function should be a goal during the perioperative period.

Effect of Intensive vs Moderate Alveolar Recruitment Strategies Added to Lung-Protective Ventilation on Postoperative Pulmonary Complications: A Randomized Clinical Trial

Importance Perioperative lung-protective ventilation has been recommended to reduce pulmonary complications after cardiac surgery. The protective role of a small tidal volume (VT) has been established, whereas the added protection afforded by alveolar recruiting strategies remains controversial. Objective To determine whether an intensive alveolar recruitment strategy could reduce postoperative pulmonary complications, when added to a protective ventilation with small VT. Design, Setting, and Participants Randomized clinical trial of patients with hypoxemia after cardiac surgery at a single ICU in Brazil (December 2011-2014). Interventions Intensive recruitment strategy (n=157) or moderate recruitment strategy (n=163) plus protective ventilation with small VT. Main Outcomes and Measures Severity of postoperative pulmonary complications computed until hospital discharge, analyzed with a common odds ratio (OR) to detect ordinal shift in distribution of pulmonary complication severity score (0-to-5 scale, 0, no complications; 5, death). Prespecified secondary outcomes were length of stay in the ICU and hospital, incidence of barotrauma, and hospital mortality. Results All 320 patients (median age, 62 years; IQR, 56-69 years; 125 women [39%]) completed the trial. The intensive recruitment strategy group had a mean 1.8 (95% CI, 1.7 to 2.0) and a median 1.7 (IQR, 1.0-2.0) pulmonary complications score vs 2.1 (95% CI, 2.0-2.3) and 2.0 (IQR, 1.5-3.0) for the moderate strategy group. Overall, the distribution of primary outcome scores shifted consistently in favor of the intensive strategy, with a common OR for lower scores of 1.86 (95% CI, 1.22 to 2.83; P = .003). The mean hospital stay for the moderate group was 12.4 days vs 10.9 days in the intensive group (absolute difference, −1.5 days; 95% CI, −3.1 to −0.3; P = .04). The mean ICU stay for the moderate group was 4.8 days vs 3.8 days for the intensive group (absolute difference, −1.0 days; 95% CI, −1.6 to −0.2; P = .01). Hospital mortality (2.5% in the intensive group vs 4.9% in the moderate group; absolute difference, −2.4%, 95% CI, −7.1% to 2.2%) and barotrauma incidence (0% in the intensive group vs 0.6% in the moderate group; absolute difference, −0.6%; 95% CI, −1.8% to 0.6%; P = .51) did not differ significantly between groups. Conclusions and Relevance Among patients with hypoxemia after cardiac surgery, the use of an intensive vs a moderate alveolar recruitment strategy resulted in less severe pulmonary complications while in the hospital. Trial Registration clinicaltrials.gov Identifier: NCT01502332

Randomized and comparative study between two intra-hospital exercise programs for heart transplant patients

OBJECTIVE To compare the effects of two physical therapy exercise in-hospital programs in pulmonary function and functional capacity of patients in the postoperative period of heart transplantation. METHODS Twenty-two heart transplanted patients were randomized to the control group (CG, n=11) and training group (TG, n=11). The control group conducted the exercise program adopted as routine in the institution and the training group has had a protocol consisting of 10 stages, with incremental exercises: breathing exercises, resistance training, stretching and walking. The programs began on the first day after extubation and stretched until hospital discharge. Assessed pulmonary function, distance walked in six minutes walk test (6MWT) and peripheral muscle strength by one repetition maximum test (1RM). RESULTS Similar behavior was observed between the two groups treated, with statistically significant increases between the first and second test of the following variables: FVC (59% in CG and 35.2% in TG); MIP (8.6% in CG and 53.5% in TG), MEP (28.8% in CG and 40.7% in TG) and 6MWT (44.5% in CG and 31.4% in TG). There was an increase of peripheral strength by 1RM test, over time, to the muscle groups of the elbow flexors, shoulder flexors, hip abductors and knee flexors. CONCLUSION Heart transplant patients benefit from exercise programs in hospital, regardless of the program type applied. A new training proposal did not result in superiority compared to routine programme applied. Exercise protocols provided improves in ventilatory variables and functional capacity of this population.

Alveolar recruitment maneuver in refractory hypoxemia and lobar atelectasis after cardiac surgery: A case report

ObjectiveThis case report describes an unusual presentation of right upper lobe atelectasis associated with refractory hypoxemia to conventional alveolar recruitment maneuvers in a patient soon after coronary artery bypass grafting surgery.MethodCase-report.ResultsThe alveolar recruitment with PEEP = 40cmH2O improved the patient’s atelectasis and hypoxemia.ConclusionIn the present report, the unusual alveolar recruitment maneuver with PEEP 40cmH2O showed to be safe and efficient to reverse refractory hypoxemia and uncommon atelectasis in a patient after cardiac surgery.

Efeitos da posição sentada na força de músculos respiratórios durante o desmame de pacientes sob ventilação mecânica prolongada no pós-operatório de cirurgia cardiovascular

O objetivo do estudo foi investigar os efeitos da posicao sentada, nos parâmetros ventilatorios e hemodinâmicos, em pacientes com suporte ventilatorio mecânico prolongado, estaveis hemodinamicamente. Participaram do estudo 40 pacientes que foram randomizados em grupo controle (n=17) e grupo intervencao (n=23). Foram mensurados parâmetros hemodinâmicos, gasometria arterial, forca muscular respiratoria e ventilometria, realizados em dois momentos: primeira e segunda avaliacao, com intervalo de 30 minutos entre as medidas. No grupo controle, as duas avaliacoes foram realizadas no leito, com a cabeceira elevada a 30°. No grupo intervencao, a primeira avaliacao foi realizada no leito (30°) e a segunda, 30 minutos apos transferencia para a poltrona, na posicao sentada (90°). A idade media da amostra foi de 64,7±11,2 anos. O resultado do estudo demonstrou que nao houve diferencas em relacao as variaveis, hemodinâmicas, gasometricas, capacidade vital forcada, volume minuto e volume de ar corrente. Entretanto, ocorreu aumento significativo da pressao inspiratoria maxima (PImax) no grupo intervencao (p<0.01). Concluimos que pacientes em pos-operatorio de cirurgia cardiovascular em ventilacao mecânica podem se beneficiar da posicao sentada durante o desmame do suporte ventilatorio, observado pela melhora da forca muscular inspiratoria (PImax). Alem disso, nao foram observadas alteracoes hemodinâmicas com a troca de postura, sendo considerado um procedimento seguro.