EVALUATION OF EFFECT OF LUNG RESECTION ON LOBAR VENTILATION AND PERFUSION USING INTRABRONCHIAL CAPNOGRAPHY

Intrabronchial capnography was applied in 11 lung cancer patients to i nvestigate the effects of lobectomy on regional lung function. Spirome try and intrabronchial capnography were performed before surgery (PRE) , and during the early (POST1,19+/-5 POD) and late (POST2, 184+/-98 PO D) postoperative periods. End-tidal carbon dioxide concentration (EtCO (2)) and Smidt's velocity profile index (V-index) were calculated from each lobar capnogram obtained bronchoscopically The V-index of lobes without cancer on the operated-on side increased after surgery (PRE, 1 0.7+/-5.0%; POST1, 14.3+/-9.4%, NS; POST2, 16.8+/-8.6%, p<0.05), while the V-index on the unoperated-on side decreased after surgery (PRE, 1 0.5+/-5.3%; POST1, 7.9+/-3.5%, p<0.05; POST2, 7.2+/-2.9%, p<0.05). EtC O(2) after surgery was lower on the operated-on side (POST1, 5.1+/-1.1 %; POST2; 4.6+/-1.1%) than on the unoperated-on side (POST1, 5.4+/-0.9 %, p<0.05; POST2, 5.0+/-0.9%, p<0.01). Since the V-index and Et-CO2 ar e compatible with the expiratory pow rate and the perfusion/ventilatio n ratio, respectively, we concluded that the air flow decreased on the operated-on side and increased on the unoperated-on side postoperativ ely and that perfusion on the operated-on side was more severely reduc ed than ventilation. These findings suggest that intrabronchial capnog raphy is useful for assessing the ventilation and perfusion of the ind ividual lobes as single units.