Abstract Introduction: Coronary artery bypass grafting (CABG) is associated with reduced ventilatory muscle strength and consequent worsening of functional capacity (FC). Inspiratory Muscle Training (IMT) can be indicated, but there is still a lack of knowledge about the use of the anaerobic threshold (AT) as a basis for prescription. The objective of this study is to evaluate if IMT based on AT modifies FC and inspiratory muscle strength of patients submitted to CABG. Methods: This is a clinical trial. On the first postoperative day, the patients were divided into two groups: the conventional group (IMT-C), which performed IMT based on 40% of maximal inspiratory pressure (MIP), and the IMT-AT group, which performed IMT based on AT. All patients underwent preoperative and postoperative assessment of MIP and performed a six-minute walk test (6MWT). Results: Forty-two patients were evaluated, 21 in each group. Their mean age was 61.4±10 years and 27 (64%) of them were male. There was a reduction of inspiratory muscle strength with a delta of 23±13 cmH2O in the IMT-C group vs. 11±10 cmH2O in the IMT-AT group (P<0.01) and of the walking distance with a delta of 94±34 meters in the IMT-C group vs. 57±30 meters in the IMT-AT group (P=0.04). Conclusion: IMT based on AT minimized the loss of FC and inspiratory muscle strength of patients submitted to CABG.

RESUMO Objetivo: Avaliar a segurança e as propriedades clinimétricas do Teste de Sentar-Levantar Cinco Vezes em pacientes mais velhos internados em unidade de terapia intensiva. Métodos: A segurança do teste foi avaliada segundo a incidência de eventos adversos e pela análise dos dados hemodinâmicos e respiratórios. Além disto, a confiabilidade de suas propriedades foi investigada por meio de avaliação de coeficientes de correlação intraclasses, mensuração do erro padrão da média, porcentagem de alteração do erro padrão da média, gráficos de Altman-Bland e de concordância-sobrevivência. Resultados: A adequabilidade do Teste de Sentar-Levantar Cinco Vezes foi identificada como baixa, já que apenas 29,8% dos potenciais participantes cumpriam os critérios de inclusão. Apenas 44% dos pacientes hospitalizados que cumpriam os critérios de inclusão realizaram o teste, sem necessidade de cessação para qualquer dos pacientes. A frequência cardíaca (79,7 ± 10,2bpm/86,6 ± 9,7bpm; p = 0,001) e a pressão arterial sistólica (118 ± 21,4mmHg/129 ± 21,5mmHg; p = 0,031) foram as únicas variáveis com aumento estatisticamente significante, sem evidência de resposta exacerbada ao teste. Além disto, não se relataram eventos adversos, e a confiabilidade tanto entre teste e reteste quanto entre avaliadores foi elevada (coeficiente de correlação entre classes ≥ 0,99). Conclusão: O Teste de Sentar-Levantar Cinco Vezes se comprovou seguro e com excelente confiabilidade. Seu uso clínico no ambiente hospitalar, contudo, pode ser restrito a pacientes adultos mais velhos com elevada funcionalidade.

ABSTRACT Objective: Assess the Five Times Sit-to-Stand Test safety and clinimetric properties in older patients hospitalized in an intensive care unit. Methods: Test safety was assessed according to the incidence of adverse events and through hemodynamic and respiratory data. Additionally, reliability properties were investigated using the intraclass correlation coefficients, standard error of measurement, standard error percentage change, Altman-Bland plot and a survival agreement plot. Results: The overall suitability of the Five Times Sit-to-Stand Test was found to be low, with 29.8% meeting the inclusion criteria. Only 44% of the hospitalized patients who met the inclusion criteria performed the test, with no need for discontinuation in any patient. Heart rate (79.7 ± 10.2bpm/86.6 ± 9.7bpm; p = 0.001) and systolic blood pressure (118 ± 21.4mmHg/129 ± 21.5mmHg; p = 0.031) were the only variables that presented a significant statistical increase, with no evidence of exacerbated response to the test. Additionally, no adverse events were reported from participating and both test-retest and interrater reliability were high (intraclass correlation coefficient ≥ 0.99). Conclusion: The Five Times Sit-to-Stand Test was proven to be safe and to have excellent reliability. Its clinical use, however, may be restricted to high-functioning older adults in hospital settings.

Resumo Fundamentos: A ventilação mecânica (VM) e a circulação extracorpórea (CEC) estão associadas a um declínio da mecânica pulmonar que pode impactar as trocas gasosas. Objetivo: Avaliar o impacto da mecânica pulmonar sobre a duração da VM e trocas gasosas no pós-operatório de cirurgia cardíaca. Métodos: Estudo de coorte realizado com pacientes submetidos a cirurgia cardíaca. Todos os pacientes foram submetidos a avaliação da mecânica pulmonar (complacência estática e resistência das vias aéreas) e gasometria arterial assim que admitidos à unidade de terapia intensiva (UTI) e foram acompanhados até o momento da extubação e, em seguida, até a alta hospitalar. Para correlacionar as variáveis preditoras com o desfecho, foi utilizado o teste de Pearson. Valores de p < 0,05 foram considerados significativos. Resultados: O estudo incluiu 50 pacientes (46 mulheres, 52%), com idade média de 57,5 ± 13,5 anos. A duração da VM foi de 7,7 ± 3,0 horas, a complacência estática foi de 35,5 ± 9,1 cm H2O, a resistência foi de 6,0 ± 2,3 cm H2O, a duração média de estadia na UTI foi de 2,9 ± 1,1 dias e o índice de oxigenação foi de 228,0 ± 33,4 mmHg. Não houve uma correlação significativa entre a duração da VM e a complacência estática (p = 0,73), porém houve uma forte correlação entre a complacência estática e as trocas gasosas (r = 0,8, p < 0,001). Conclusão: A mecânica pulmonar apresenta forte correlação com as trocas gasosas e fraca correlação com a duração da VM no pós-operatório de cirurgia cardíaca.

Abstract Background: Mechanical ventilation (MV) and extracorporeal circulation (ECC) are associated with a decline in pulmonary mechanics that may affect gas exchange. Objective: To evaluate the impact of pulmonary mechanics on MV duration and gas exchange in the postoperative period of cardiac surgery. Methods: This was a cohort study in patients undergoing cardiac surgery. All patients underwent evaluation of pulmonary mechanics (static compliance and airway resistance) and arterial blood gas analysis upon admission to the intensive care unit (ICU) and were followed up until extubation and hospital discharge. Results: The study included 50 patients (46 women, 52%) with a mean age of 57.5 ± 13.5 years. The MV duration was 7.7 ± 3.0 hours, static compliance was 35.5 ± 9.1 cm H2O, resistance was 6.0 ± 2.3 cm H2O, mean length of ICU stay was 2.9 ± 1.1 days, and oxygenation index was 228.0 ± 33.4 mmHg. No significant correlation was found between MV duration and static compliance (p = 0.73), but a strong correlation was found between static compliance and gas exchange (r = 0.8 and p < 0.001). Conclusion: Pulmonary mechanics have a strong correlation with gas exchange and a weak correlation with MV duration after cardiac surgery.

Abstract Introduction: Cardiac surgery is a highly complex procedure which generates worsening of lung function and decreased inspiratory muscle strength. The inspiratory muscle training becomes effective for muscle strengthening and can improve functional capacity. Objective: To investigate the effect of inspiratory muscle training on functional capacity submaximal and inspiratory muscle strength in patients undergoing cardiac surgery. Methods: This is a clinical randomized controlled trial with patients undergoing cardiac surgery at Instituto Nobre de Cardiologia. Patients were divided into two groups: control group and training. Preoperatively, were assessed the maximum inspiratory pressure and the distance covered in a 6-minute walk test. From the third postoperative day, the control group was managed according to the routine of the unit while the training group underwent daily protocol of respiratory muscle training until the day of discharge. Results: 50 patients, 27 (54%) males were included, with a mean age of 56.7±13.9 years. After the analysis, the training group had significant increase in maximum inspiratory pressure (69.5±14.9 vs. 83.1±19.1 cmH2O, P=0.0073) and 6-minute walk test (422.4±102.8 vs. 502.4±112.8 m, P=0.0031). Conclusion: We conclude that inspiratory muscle training was effective in improving functional capacity submaximal and inspiratory muscle strength in this sample of patients undergoing cardiac surgery.

Resumo Introdução : Os pacientes submetidos à cirurgia cardiovascular apresentam complicações motoras e respiratórias decorrentes principalmente de alta manipulação cirúrgica e do uso de ventilação mecânica. Pode-se diminuir a incidência de complicações pulmonares e o tempo de hospitalização reduzindo-se o tempo de início de desmame e desconectando o paciente precocemente do suporte ventilatório. As complicações motoras são as mais pertinentes, pois afetam diretamente a independência funcional pelo tempo de imobilismo. Objetivos : Identificar se existe impacto do tempo de ventilação mecânica sobre a capacidade funcional em pacientes submetidos à cirurgia cardíaca com a finalidade de contribuir com o estabelecimento de evidências confiáveis para as práticas nesse perfil de paciente. Materiais e métodos : Foram analisados artigos originais, publicados entre 2000 e 2014, que abordassem sobre a influência do tempo de ventilação mecânica sobre a independência funcional de pacientes submetidos à cirurgia cardíaca, contidas nas seguintes bases de dados eletrônicos: Scielo, BIREME (LILACS), PubMed e CAPES. Resultados : Observou-se que o tempo de permanência na unidade de terapia intensiva nas cirurgias cardíacas foi influenciado diretamente pelo tempo de CEC, VM e disfunção pulmonar. A independência funcional esteve comprometida em pacientes com maior tempo de VM, dor no pós-operatório e tempo prolongado de restrição ao leito. Também se verificou que não há consenso em relação ao protocolo para melhora da capacidade funcional. Conclusão : Existe uma declínio funcional nos pacientes submetidos a cirurgia cardíaca, principalmente naqueles em maior tempo de permanência na ventilação mecânica, refletindo de forma direta e negativa na sua independência funcional e qualidade de vida.

Abstract Introduction: Patients submitted to cardiovascular surgery present motor and respiratory complications mainly due to high surgery manipulation and the use of mechanical ventilation. Reducing the weaning start time and disconnecting patient's ventilation system prematurely can decrease the pulmonary complications and hospitalization time. Motor complications are the most relevant as they have a direct effect on functional independence provoked by immobility time. Objectives : Identify if mechanical ventilation time has an impact on functional capacity on patients submitted to cardiac surgery in order to contribute to the establishment of reliable evidence to practice through this patient's profile. Materials and methods : Original articles were analyzed, published between 2000 and 2014, which focused on the influence of mechanical ventilation time concerning the functional independence on patients submitted to cardiac surgery, contained in the following electronic database: Scielo, BIREME (LILACS), PubMed e CAPES. Results : It was observed that the length of stay in the intensive care unit in cardiac surgery was influenced directly by CPB, VM and pulmonary dysfunction. Functional independence was compromised in patients with longer duration of mechanical ventilation, postoperative pain and prolonged bed rest. It was also found that there is no consensus on the protocol for improved functional capacity. Conclusion : There is a functional decline in patients undergoing cardiac surgery, especially those at increased length of stay in mechanical ventilation, reflecting a direct and negative impact on their functional independence and quality of life.