Evaluation before thoracotomy.

When a thoracotomy is being considered, the physician must first determine whether the lesion is potentially resectable. However, an equally important decision is whether the patient can tolerate pulmonary resection if there are other serious underlying medical problems. In any patient with signs or symptoms of pulmonary disease, a spirogram, arterial blood gas study and electrocardiogram should be done as part of the routine preoperative evaluation. The detection of abnormal pulmonary function should prompt preoperative institution of respiratory care to optimize maximally a patient's cardiorespiratory status before operation. If any of several indicators of a high risk of postoperative cardiopulmonary problems are found, split pulmonary function studies should be done to determine whether the lung remaining after resection will have adequate ventilation and perfusion. Xenon radiospirometry is preferable to bronchospirometry and right heart catheterization because of its noninvasiveness. Resection should not be undertaken in the presence of a predicted postoperative forced expiratory volume in one second (FEV(1)) less than 0.8 liter, an arterial carbon dioxide partial pressure (PaCO(2)) greater than 45 mm of mercury or Xenon scans which show poor ventilation/perfusion ( V/ Q) matchup in what would be the remaining lung after resection. A case is reported which shows the value of this approach to preoperative evaluation in determining the risk of postoperative problems.