RESUMO
Obstructive sleep apnoea syndrome (OSAS) often coexists in patients with chronic obstructive pulmonary disease (COPD). The present prospective cohort study tested the effect of OSAS treatment with continuous positive airway pressure (CPAP) on the survival of hypoxaemic COPD patients. It was hypothesised that CPAP treatment would be associated with higher survival in patients with moderate-to-severe OSAS and hypoxaemic COPD receiving long-term oxygen therapy (LTOT). Prospective study participants attended two outpatient advanced lung disease LTOT clinics in São Paulo, Brazil, between January 1996 and July 2006. Of 603 hypoxaemic COPD patients receiving LTOT, 95 were diagnosed with moderate-to-severe OSAS. Of this OSAS group, 61 (64%) patients accepted and were adherent to CPAP treatment, and 34 did not accept or were not adherent and were considered not treated. The 5-yr survival estimate was 71% (95% confidence interval 53-83%) and 26% (12-43%) in the CPAP-treated and nontreated groups, respectively (p<0.01). After adjusting for several confounders, patients treated with CPAP showed a significantly lower risk of death (hazard ratio of death versus nontreated 0.19 (0.08-0.48)). The present study found that CPAP treatment was associated with higher survival in patients with moderate-to-severe OSAS and hypoxaemic COPD receiving LTOT.
Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Hipóxia/mortalidade , Hipóxia/terapia , Oxigenoterapia , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/terapia , Síndromes da Apneia do Sono/mortalidade , Síndromes da Apneia do Sono/terapia , Idoso , Feminino , Humanos , Hipóxia/complicações , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/complicações , Índice de Gravidade de Doença , Síndromes da Apneia do Sono/complicações , Taxa de SobrevidaRESUMO
BACKGROUND: Respiratory muscle unloading during exercise could improve locomotor muscle oxygenation by increasing oxygen delivery (higher cardiac output and/or arterial oxygen content) in patients with chronic obstructive pulmonary disease (COPD). METHODS: Sixteen non-hypoxaemic men (forced expiratory volume in 1 s 42.2 (13.9)% predicted) undertook, on different days, two constant work rate (70-80% peak) exercise tests receiving proportional assisted ventilation (PAV) or sham ventilation. Relative changes (Delta%) in deoxyhaemoglobin (HHb), oxyhaemoglobin (O(2)Hb), tissue oxygenation index (TOI) and total haemoglobin (Hb(tot)) in the vastus lateralis muscle were measured by near-infrared spectroscopy. In order to estimate oxygen delivery (Do(2)est, l/min), cardiac output and oxygen saturation (Spo(2)) were continuously monitored by impedance cardiography and pulse oximetry, respectively. RESULTS: Exercise tolerance (Tlim) and oxygen uptake were increased with PAV compared with sham ventilation. In contrast, end-exercise blood lactate/Tlim and leg effort/Tlim ratios were lower with PAV (p<0.05). There were no between-treatment differences in cardiac output and Spo(2) either at submaximal exercise or at Tlim (ie, Do(2)est remained unchanged with PAV; p>0.05). Leg muscle oxygenation, however, was significantly enhanced with PAV as the exercise-related decrease in Delta(O(2)Hb)% was lessened and TOI was improved; moreover, Delta(Hb(tot))%, an index of local blood volume, was increased compared with sham ventilation (p<0.01). CONCLUSIONS: Respiratory muscle unloading during high-intensity exercise can improve peripheral muscle oxygenation despite unaltered systemic Do(2 )in patients with advanced COPD. These findings might indicate that a fraction of the available cardiac output had been redirected from ventilatory to appendicular muscles as a consequence of respiratory muscle unloading.
Assuntos
Exercício Físico/fisiologia , Oxigênio/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Músculos Respiratórios/fisiologia , Dióxido de Carbono/sangue , Dióxido de Carbono/fisiologia , Débito Cardíaco/fisiologia , Tolerância ao Exercício/fisiologia , Humanos , Masculino , Músculo Esquelético/fisiologia , Oxigênio/sangue , Consumo de Oxigênio/fisiologia , Pressão Parcial , Respiração Artificial , Espectroscopia de Luz Próxima ao InfravermelhoRESUMO
No presente trabalho, sao descritos os achados cinecoronariograficos e os aspectos evoluativos de sete pacientes com infarto do miocardio transmural, caracterizado do ponto de vista clinico, eletrocardiografico e enzimatico. Todos eram do sexo masculino, com idade media de 35 anos e nao portadores de multiplos fatores de risco, sendo o tabagismo o fator mais presente. O exame cinecoronariografico foi realizado em todo o grupo, com um tempo medio de 90 dias apos o quadro agudo, nao sendo encontrada lesao coronariana significativa em nenhum dos casos, mas ventriculografia esquerda estava alterada em 5 deles.Obito, insuficiencia cardiaca, angor e disturbio de conducao estiveram presentes na evolucao. Ate o momento a patogenia, a incidencia e a historia natural deste tipo particular de infarto do miocardio nao sao claras, parecendo que trombose e espasmo coronariano podem explicar, em parte, a sua genese