Pilot study on prevention of lung injury during surgery for type A acute aortic dissection: no evident improvements with celsior flushing through the pulmonary artery

OBJECTIVE: Postoperative respiratory failure is a frequent and serious complication in patients with type A acute aortic dissection. Experimental evidence suggests that pulmonary artery perfusion using hypothermic protective solutions helps prevent lung injury. The aim of this pilot prospective study was to evaluate the effect of pulmonary artery flushing during selective cerebral perfusion (SCP) on lung function. METHODS: Twenty patients referred for acute type A aortic dissection, who were free from preoperative respiratory dysfunction, were assigned prospectively and alternately to two treatment groups. Pulmonary flushing was performed during SCP in group P (10 patients), while conventional Kazui technique was applied in group N (10 patients). Lung perfusion consisted of single-shot hypothermic pulmonary artery flush with Celsior. Lung function was evaluated by intubation time, scoring of chest radiograms at 12 hours after CPB, and PaO2/FiO2 assessed from immediately before surgery to 72 hours after termination of cardiopulmonary bypass. RESULTS: Incidence of pre, intra and post operative determinants of lung dysfunction proved homogeneous in both groups. Lung oxygenation function showed a marked post operative decline followed by a slow improvement in both groups. Analysis of respiratory ratios did not disclose significant differences even though the flushed group had a better performance in all study patients. The incidence of prolonged ventilator support (longer than 72 hours) (30% vs 20%, p = NS) and severity of x-ray pulmonary infiltrate score were comparable (mean score 1.7 +/- 0.71 vs 1.6 +/- 0.68, p = NS). CONCLUSIONS: Pulmonary artery flushing with Celsior solution does not seem to provide an effective preservation of lung function.