SummaryWe have studied prospectively the clinical course and serum concentrations of thromboxane B 2 (TxB 2 ) and leukotriene B 4 (LTB 4 ) in patients developing adult respiratory distress syndrome (ARDS) after oesophagectomy. The clinical course was assessed according to a validated ARDS score, and intra-and postoperative measurements of TxB 2 and LTB 4 in pre-and post-pulmonary blood were performed in 18 patients undergoing oesophagectomy for oesophageal carcinoma and 11 control patients undergoing thoracotomy and pulmonary resection. Six of 18 patients undergoing oesophagectomy, but no control patient, developed ARDS. The ARDS score was highest on day 8 after operation. Only patients with ARDS had a significant postoperative increase in postpulmonary, but not pre-pulmonary, TxB 2 concentrations (P : 0.05 vs patients without ARDS).This study provides evidence that TxA 2 , originating from the lungs, was associated with the development of ARDS after oesophageal resection. In view of the high incidence of ARDS after oesophagectomy (10-30%), prophylactic treatment of patients undergoing oesophageal resection with clinically applicable thromboxane synthetase inhibitors may be warranted. (Br. J. Anaesth. 1998; 80: 36-40) Keywords: lung adult respiratory distress syndrome; complications, adult respiratory distress syndrome; surgery, gastrointestinal; hormones, thromboxane; hormones, leukotrienes Adult respiratory distress syndrome (ARDS) is one of the primary contributors to mortality in ICU patients. 1 A wide variety of clinical conditions such as sepsis, burns, trauma 2-4 and major surgery, and oesophageal resections in particular, 5 6 predispose to the development of ARDS. In a meta-analysis of more than 60 000 patients undergoing oesophagectomy, 27% developed ARDS after transthoracic resection and 13% after transhiatal resection. 7 The following factors appear to increase the risk of postoperative ARDS in patients with oesophageal carcinoma: smoking and chronic obstructive pulmonary disease (COPD), transthoracic mobilization of the oesophagus with contusion of the lung during extensive surgery and postoperative (silent) aspiration. 8 Because of the heterogenity of sepsis or trauma patients, it is difficult to acquire comparable study populations for clinical studies of ARDS. In these patients, the triggering insult for ARDS is seldom predictable and it varies greatly in intensity; also, patient conditions such as age, immune and nutritional status and coexisting medical conditions vary widely. Patients undergoing oesophageal resection for oesophageal carcinoma, however, are a homogenous group, with 1-3 of 10 patients developing ARDS. 7 They are usually aged 50-70 yr, the majority have a history of smoking and preoperative weight loss, they are suffering from the same underlying disease, and the duration and magnitude of the insult triggering ARDS (i.e. oesophageal resection) is uniform. In addition, these patients are unique in that they are exposed to a planned triggering factor (i.e. oesophageal resection) ...