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 physical training on the ventilatory response to exercise in patients on chronic hemodialysis / 体力科学

This study examined the effects of physical training on exercise hyperpnea (EH) in patients on hemodialysis (HD) . In baseline, 17 (trained group) and 12 (control group) patients on HD performed symptom limited exercise test using a treadmill. Trained group, but not control group, exercised 2 to 3 times weekly on non-dialysis days under medical supervision. Exercise testing was repeated 20 weeks after the baseline. Ventilatory response to exercise was evaluated using the regression slope relating minute ventilation (VE) to carbon dioxide output (VCO<SUB>2</SUB> ) during incremental exercise (VE/VCO<SUB>2</SUB> slope) below the point of respiratory compensation. In trained group, VE, oxygen uptake ( VO<SUB>2</SUB>) and VCO<SUB>2</SUB> at peak exercise increased and VE/VO<SUB>2</SUB> and VE/VCO<SUB>2</SUB> decreased after physical training, respectively. No change was observed in control group. VO<SUB>2</SUB> at the anaerobic threshold increased in trained group, but not in control group. The post training VE/VCO<SUB>2</SUB> slope (33.9±5.0) was significantly (p<0.05) lower than the pre-training slope (38.0± 4.8) and remained constant in control group. In trained group, changes in the VE/VCO<SUB>2</SUB> slope correlated with those in peak VO<SUB>2</SUB> (p<0.05) . These results suggest that physical training decreases EH in patients on HD and that it correlates with changes in exercise tolerance.