Does Inhaled Salbutamol Prevent Lung Edema After Thoracic Surgery? A Randomized Controlled Study

Material and Methods Patient selection Consecutive patients who require elective lung resection for cancer at the University Hospital of Geneva will be screened for the presence of risk factors for postoperative ALI or hydrostatic lung edema: age > 60 yrs, history of chronic alcohol consumption (>60g/day), prior radiation or chemotherapy, cardiac insufficiency (left ventricular ejection fraction < 40%, or a history of past acute heart failure), coronary artery disease (history of myocardial infarct, Q wave on the ECG, positive stress test or coronary angiogram), recent pneumonia (within 6 weeks of hospital admission), reduced diffusion capacity for carbon monoxide (DLCO < 60% of predicted values) and predicted postoperative lung perfusion of < 55% of total lung perfusion. Patients with at least 3 risk factors for postoperative lung edema will be considered eligible for the study. Patients undergoing pneumonectomy or presenting with intracardiac shunts, valvular diseases or aortic abdominal aneurysm will all be excluded as these conditions preclude valid measurements of extravascular lung water volumes. In addition, chronic treatment with inhaled bronchodilators, a history of any adverse reaction to bronchodilators and liver or kidney insufficiencies will be considered exclusion criteria.

This randomized double blind, cross-over study has been approved by the local university hospital ethics committee and written informed consent has been obtained from all selected patients.

The same team of pneumonologists, thoracic surgeons and anesthesiologists/intensive care physicians will be involved in the perioperative medical management. In addition to history and clinical examination, a standardized preoperative assessment includes chest radiography, ECG, pulmonary function testing as well as computed tomography scans and positron emission tomographies of the chest, abdomen and brain. Quantitative lung perfusion/ventilation scanning, brain imaging, maximal aerobic capacity and myocardial stress testing will be performed when appropriate in intermediate-to-high risk surgical candidates.

Operative and anesthetic management Routinely, antimicrobial prophylaxis with cefazoline will be administered for 24 hours and an epidural catheter was inserted at the 4th-5th or at the 5th-6th vertebral interspace. Thoracic epidural anesthesia (TEA) will be initiated preoperatively with the administration of bupivacaïne 0.25% and continued postoperatively with a lower dosage (bupivacaine 0.1%) that was combined with opiates (fentanyl 2 mcg/ml).

Each patient will be equipped with a 4-French femoral artery catheter and an internal jugular venous line that will be connected to a pulse contour cardiac output monitor (PV2024L; Pulsion Medical Systems AG, Munich, Germany).