Objective: We evaluated the usefulness of analyzing expired gas during exercise testing for the prediction of postoperative cardiopulmonary complications in patients with esophageal carcinoma.
Background data: Radical esophagectomy with 3-field lymphadenectomy is performed in patients with thoracic esophageal carcinoma but has a high risk of postoperative complications. To reduce the surgical risk, we performed preoperative risk analysis using 8 factors. Although hospital mortality was decreased when this risk analysis was used, severe cardiopulmonary complications still occurred.
Methods: The study group consisted of 91 patients who had undergone curative esophagectomy with 3-field lymphadenectomy. The maximum oxygen uptake, anaerobic threshold, vital capacity, percent vital capacity, forced expiratory volume in 1 second, percent forced expiratory volume, V.(25)/HT, forced expired flow at 75% of forced vital capacity to height ratio (FEF(75%)/HT), forced expired flow at 50% to 75% of forced vital capacity ratio (FEF(50%)/FEF(75%)), percent diffusion capacity for carbon monoxide, and arterial oxygen tension were measured. Patients were divided into 2 groups on the basis of the presence or absence of postoperative cardiopulmonary complications.
Results: Only the maximum oxygen uptake was significantly different between the 2 groups. All patients were grouped according to the value of the maximum oxygen uptake, and the occurrence of postoperative cardiopulmonary complications was calculated for each group. A cardiopulmonary complication rate of 86% was found for patients with a maximum oxygen uptake of less than 699 mL. min(-1). m(-2); for those with a value of 700 to 799 mL. min(-1). m(-2), the complication rate was 44%.
Conclusions: The maximum oxygen uptake obtained by expired gas analysis during exercise testing correlates with the postoperative cardiopulmonary complication rate. On the basis of these results, esophagectomy with 3-field lymphadenectomy can be safely performed in patients with a maximum oxygen uptake of at least 800 mL. min(-1). m(-2).