Effects of a high-intensity pulmonary rehabilitation program on the minute ventilation/carbon dioxide output slope during exercise in a cohort of patients with COPD undergoing lung resection for non-small cell lung cancer / Efeitos de um programa de reabilitação de alta intensidade no comando VE/VCO2 durante exercício em um grupo de pacientes submetidos à ressecção para câncer de pulmão de células não pequenas

ABSTRACT Objective: Preoperative functional evaluation is central to optimizing the identification of patients with non-small cell lung cancer (NSCLC) who are candidates for surgery. The minute ventilation/carbon dioxide output (VE/VCO2) slope has proven to be a predictor of surgical complications and mortality. Pulmonary rehabilitation programs (PRPs) could influence short-term outcomes in patients with COPD undergoing lung resection. Our objective was to evaluate the effects of a PRP on the VE/VCO2 slope in a cohort of patients with COPD undergoing lung resection for NSCLC. Methods: We retrospectively evaluated 25 consecutive patients with COPD participating in a three-week high-intensity PRP prior to undergoing lung surgery for NSCLC, between December of 2015 and January of 2017. Patients underwent complete functional assessment, including spirometry, DLCO measurement, and cardiopulmonary exercise testing. Results: There were no significant differences between the mean pre- and post-PRP values (% of predicted) for FEV1 (61.5 ± 22.0% vs. 62.0 ± 21.1%) and DLCO (67.2 ± 18.1% vs. 67.5 ± 13.2%). Conversely, there were significant improvements in the mean peak oxygen uptake (from 14.7 ± 2.5 to 18.2 ± 2.7 mL/kg per min; p < 0.001) and VE/VCO2 slope (from 32.0 ± 2.8 to 30.1 ± 4.0; p < 0.01). Conclusions: Our results indicate that a high-intensity PRP can improve ventilatory efficiency in patients with COPD undergoing lung resection for NSCLC. Further comprehensive prospective studies are required to corroborate these preliminary results.

RESUMO Objetivos: A avaliação funcional pré-operatória é fundamental para otimizar a seleção dos pacientes para cirurgia torácica para tratamento do CPCNP. Uma alta inclinação VE/VCO2 se mostrou um preditor de complicações cirúrgicas e de aumento da mortalidade. Programas de reabilitação pulmonar (PRP) demonstraram aumentar os parâmetros funcionais e os desfechos de curto prazo em pacientes com DPOC submetidos à ressecção pulmonar. O impacto dos PRP na inclinação VE/VCO2 não foi totalmente investigado. Métodos: Avaliamos retrospectivamente 25 pacientes com DPOC consecutivos submetidos aos efeitos de um programa de reabilitação pulmonar de alta intensidade (PRP) na inclinação VE/VCO2. Resultados: Não foram observadas variações significativas nos principais parâmetros espirométricos após o programa de reabilitação de três semanas (pré-reabilitação VEF1 versus pós-reabilitação VEF1 %prev: 61,5 ± 22,0% para 62,0 ± 21,1%, ns; pré-reabilitação DLCO para pós-reabilitação DLCO %prev: 67,2 ± 18,1% para 67,5 ± 13,2%, ns). Por outro lado, o pico de VO2 e a inclinação VE/VCO2 melhoraram significativamente após PRP (pico de VO2 pré-reabilitação para pico de VO2 pós-reabilitação: 14,7 ± 2,5 para 18,2 ± 2,7 mL/kg/min, p < 0,0000001; inclinação pré-reabilitação VE/VCO2 para pós-reabilitação inclinação VE/VCO2: 32,0 ± 2,8 para 30,1 ± 4,0, p<0,01). Conclusão: Documentamos o benefício no desempenho físico de um treinamento de três semanas em um grupo de pacientes com DPOC com um comprometimento funcional notável em parâmetros de esforço. Dados adicionais e mais abrangentes são necessários para esclarecer os mecanismos fisiológicos.

Effects of high-intensity inspiratory muscle training associated with aerobic exercise in patients undergoing cabg: randomized clinical trial

Abstract Objective: Evaluate the interaction between high-intensity inspiratory muscle training (IMT) and aerobic exercise on physical capacity, respiratory muscle strength, peripheral muscle strength, and quality of life of patients who underwent coronary artery bypass grafting (CABG). Methods: Twenty-four patients underwent CABG were randomized into two groups. During 36 sessions, one group received IMT associated with aerobic exercise and the other group received only aerobic exercise. Primary outcome was the distance in the six-minute walk distance (6MWD) test. Secondary outcomes included respiratory muscle strength, peripheral muscle strength, and quality of life. Measures were taken at the baseline, at the 12th session, the 24th session, and 36th session. Results: Baseline characteristics were similar between the groups. There was no statistically significant difference between the two groups in any outcome [6MWD - P=0.935; peak oxygen consumption (PeakVO2) - P=0.853; maximal inspiratory pressure (MIP) - P=0.243; maximal expiratory pressure (MEP) - P=0.268; sitting-rising test (SRT) - P=0.212], but there was interaction in MIP (P=0.000) and all outcomes improved in the two groups (6MWD - P=0.000; PeakVO2 - P=0.000; MIP - P=0.000; MEP - P=0.000; SRT - P=0.000). Conclusion: There was an improvement of all outcomes in both groups, but IMT was not able to provide additional benefits. The use of this combination should be used with caution to not generate higher costs in the rehabilitation process of these patients.

Gradiente de saturação de oxigênio e concentração de lactato entre átrio direito e artéria pulmonar no pós-operatório imediato de cirurgia cardíaca com circulação extracorpórea / Oxygen saturation and lactate concentration gradient from the right atrium to the pulmonary artery in the immediate postoperative following cardiac surgery with extracorporeal circulation

RESUMO Objetivo: Caracterizar as modificações na concentração sanguínea do lactato e da saturação de oxigênio em pacientes no pós-operatório imediato de cirurgia cardíaca com circulação extracorpórea. Métodos: Foram coletadas amostras de sangue de 35 pacientes, de forma rápida e aleatória, do acesso arterial e das portas proximal e distal de um cateter pulmonar. Resultados: Não foram verificadas diferenças estatisticamente significantes entre saturação de oxigênio no átrio direito (72% ± 0,11%) e na artéria pulmonar (71% ± 0,08%). A concentração sanguínea de lactato no átrio direito foi de 1,7mmol/L ± 0,5mmol/L, enquanto na artéria pulmonar esta concentração foi de 1,6mmol/L ± 0,5mmol/L (p < 0,0005). Conclusão: A diferença entre as concentrações sanguíneas de lactato no átrio direito e na artéria pulmonar pode ser consequência da baixa concentração de lactato no sangue do seio coronário, já que o lactato é um importante substrato para o miocárdio durante este período. A ausência de diferenças entre saturação sanguínea de oxigênio no átrio direito e na artéria pulmonar sugere extração de oxigênio mais baixa pelo miocárdio, em razão do menor consumo de oxigênio.

ABSTRACT Objective: This prospective study aimed to characterize the changes in blood lactate concentration and blood oxygen saturation in patients during the immediate postoperative period of cardiac surgery with extracorporeal circulation. Methods: Blood samples were collected from 35 patients in a rapid and random order from the arterial line and from the proximal and distal port of a pulmonary artery catheter. Results: The results showed no statistically significant differences between the blood oxygen saturation in the right atrium (72% ± 0.11%) and the blood oxygen saturation in the pulmonary artery (71% ± 0.08%). The blood lactate concentration in the right atrium was 1.7mmol/L ± 0.5mmol/L, and the blood lactate concentration in the pulmonary artery was 1.6mmol/L ± 0.5mmol/L (p < 0.0005). Conclusion: The difference between the blood lactate concentration in the right atrium and the blood lactate concentration in the pulmonary artery might be a consequence of the low blood lactate concentration in the blood from the coronary sinus, as it constitutes an important substrate for the myocardium during this period. The lack of differences between the blood oxygen saturation in the right atrium and the percentage of blood oxygen saturation in the pulmonary artery suggests a lower oxygen extraction by the myocardium given a lower oxygen consumption.

O sangue venoso coletado do acesso femoral é adequado para estimar a saturação venosa central de oxigênio e os níveis de lactato arterial em pacientes graves? / Is venous blood drawn from femoral access adequate to estimate the central venous oxygen saturation and arterial lactate levels in critically ill patients?

RESUMO Objetivos: Testar se amostras de sangue venoso coletadas do acesso femoral podem ser utilizadas para estimar a saturação venosa central de oxigênio e os níveis de lactato arterial em pacientes graves. Métodos: Foram utilizadas a análise de Bland-Altman e correlações de Spearman para comparar a saturação venosa femoral de oxigênio e a saturação venosa central de oxigênio, assim como os níveis de lactato arterial e femoral. Foi conduzida uma análise predeterminada de subgrupos nos pacientes com sinais de hipoperfusão. Além disso, foi também investigada a concordância clínica. Resultados: Foram obtidas amostras sanguíneas de 26 pacientes. Em 107 amostras pareadas, observou-se correlação moderada (r = 0,686; p < 0,0001) entre a saturação venosa central de oxigênio e a saturação venosa femoral de oxigênio, com um viés de 8,24 ± 10,44 (limites de concordância de 95%: -12,23 a 28,70). Em 102 amostras pareadas, houve forte correlação entre os níveis arteriais de lactato e os níveis de lactato femoral (r = 0,72, p < 0,001) com um viés de -2,71 ± 9,86 (limites de concordância de 95%: -22,3 a 16,61). A presença de hipoperfusão não modificou de forma significante os resultados. A concordância clínica para saturação venosa foi inadequada, com diferentes decisões terapêuticas em 22,4% das situações; para o lactato, isto ocorreu em apenas 5,2% das situações. Conclusão: A saturação venosa de oxigênio femoral não deve ser utilizada em substituição da saturação venosa central de oxigênio. No entanto, os níveis femorais de lactato podem ser utilizados na prática clínica, mas com cautela.

ABSTRACT Objectives: The purpose of this study was to test if venous blood drawn from femoral access can be used to estimate the central venous oxygen saturation and arterial lactate levels in critically ill patients. Methods: Bland-Altman analysis and Spearman correlations were used to compare the femoral venous oxygen saturation and central venous oxygen saturation as well as arterial lactate levels and femoral lactate. A pre-specified subgroup analysis was conducted in patients with signs of hypoperfusion. In addition, the clinical agreement was also investigated. Results: Blood samples were obtained in 26 patients. In 107 paired samples, there was a moderate correlation (r = 0.686, p < 0.0001) between the central venous oxygen saturation and femoral venous oxygen saturation with a bias of 8.24 ± 10.44 (95% limits of agreement: -12.23 to 28.70). In 102 paired samples, there was a strong correlation between the arterial lactate levels and femoral lactate levels (r = 0.972, p < 0.001) with a bias of -2.71 ± 9.86 (95% limits of agreement: -22.03 to 16.61). The presence of hypoperfusion did not significantly change these results. The clinical agreement for venous saturation was inadequate, with different therapeutic decisions in 22.4% of the situation; for lactate, this was the case only in 5.2% of the situations. Conclusion: Femoral venous oxygen saturation should not be used as a surrogate of central venous oxygen saturation. However, femoral lactate levels can be used in clinical practice, albeit with caution.

Energy restriction and impact on indirect calorimetry and oxidative stress in cardiac tissue in rat.

Caloric restriction, defined as a reduction in calorie intake below ad libitum, without malnutrition can have beneficial effects. In this study, we evaluated the impact of caloric restriction of 30 and 60% on calorimetric parameters and oxidative stress in cardiac tissue in rats. Rats were randomly divided into 3 groups (n = 8): G1 = control; G2 = rats exposed to dietary restriction of 30%; and G3 = rats exposed to dietary restriction of 60%. Energy restriction decreased final body weight, oxidation of carbohydrates and lipid, oxygen consumption (VO2), carbon dioxide production (VCO2), resting metabolic rate (RMR), but elevated respiratory quotient (RQ). G3 animals also displayed an imbalance in the oxidant/antioxidant system, as revealed by the decrease in the lipid hydroperoxide (LH) level and GSH-Px activity in heart tissue. In conclusion, dietary restriction decreased oxidative metabolism, as seen by the colorimetric profiles and controlled oxidative stress in cardiac tissue.