Preoperative spirometry versus expired gas analysis during exercise testing as predictors of cardiopulmonary...

As cardiopulmonary load increases with the amount of lung resected, to perform surgery safely it is important to be able to predict cardiopulmonary insufficiency. However, lung function testing with spirometry and blood gas analysis does not accurately measure cardiopulmonary reserve. We conducted this study to evaluate expired gas analysis during exercise testing for predicting postoperative complications after lung resection.

Expired gas analysis during exercise and spirometry were done 1 week preoperatively in 211 patients who underwent pulmonary resection for lung cancer. Patients were divided postoperatively according to whether cardiopulmonary complications were absent (group A) or present (group B).

In group B there were more men than women (P < 0.01), and the mean age was greater (P < 0.05). There was no difference in disease stage, but more patients underwent pneumonectomy in group B than in group A ( P < 0.005). The results of expired gas analysis during exercise testing and of spirometry showed that maximum oxygen uptake/m(2) (P < 0.0005), anaerobic threshold/m(2) (P < 0.01), vital capacity (VC)/m(2) (P < 0.005), %VC (P < 0.0001), forced expiratory volume in 1 s (FEV(1.0))/m(2) (P < 0.0001), and FEV(1.0%) (P < 0.05) were lower in group B than in group A.

The combination of expired gas analysis during exercise and conventional pulmonary function tests identified patients at risk for postoperative cardiopulmonary complications following pulmonary resection.