Preoperative evaluation of cardiopulmonary reserve with the use of expired gas analysis during exercise testing in patients with squamous cell carcinoma of the thoracic esophagus

Abstract

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, V̇25/HT, forced expired flow at 75% of forced vital capacity to height ratio (FEF75%/HT), forced expired flow at 50% to 75% of forced vital capacity ratio (FEF50%/FEF75%), 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. (J Thorac Cardiovasc Surg 2001;121:1064-8)