RESUMEN
Objective We generated an experimental canine model of heterogeneous emphysema.The dogs subsequently underwent unilateral bronchoscopic lung volume reduction(BLVR).Observing the postoperative condition of ventilation/perfusion,blood gas analysis,respiratory dynamics,hemodynamic measurement,HRCT and radiologic outcomes,compared with the preoperative level,the correlative mechanism and the effects of BLVR were analyzed.Methods There were 15 healthy dogs that were treated samely with localized papain instillations under bronchoscopic guidance to generate heterogeneous emphysema.The right dorsal lobe was selected as the target area.All dogs were divided into 3 groups randomly.Group A was control group;Group B and Group C received BLVR 6 weeks later while group A was raised as the same way.Group B underwent endobronchial valve insertion(EVI);Group C underwent bronchial blocking with albumin gel.Measurements were made in each animal at 3 time points:prior to papain exposure(base-line),after establishment of emphysema(6 weeks later),6 weeks after BLVR.Data included blood gas analysis(PaO2,PaCO2),respiratory dynamics(respiratory peak pressure,lung compliance),hemodynamic measurement(pulmonary artery pressure,pulmonary capillary vessel wedge pressure),nuclear ventilation/perfusion scan(CTS,CTS/PIX).Dogs were euthanized at 6-week time point followed by autopsy.The data was statistically managed and compared.Results After development of emphysema,all dogs exhibitted aggravation in PaO2,PaCO2,PAP and lung compliance(P0.05).Through ventilation/perfusion scan,CTS/PIX of the target areas reduced(P