Lung reperfusion injury in patients after balloon angioplasty for pulmonary artery stenosis.

OBJECTIVES To determine the incidence and degree of acute lung reperfusion injury (ARI) in patients undergoing balloon angioplasty of branch pulmonary artery stenosis and to evaluate the correlation and efficacy of an oxygenation index in confirming the clinical diagnosis. DESIGN Retrospective, single-center observational study. SETTING Cardiac catheterization laboratory at a tertiary care children's hospital. PATIENTS Patients with congenital heart disease undergoing pulmonary artery balloon angioplasty. INTERVENTION Review of patient medical and catheterization records. MEASUREMENTS AND MAIN RESULTS The records of all patients with biventricular physiology undergoing balloon angioplasty of branch pulmonary artery stenosis over a period of 2 years (12/2006-12/2008) were reviewed. Data collection included demographics, details of pulmonary artery intervention, right ventricle/femoral artery systolic pressure (RV/FA) ratio, and post-procedure recovery condition. Markers of ARI, including clinical, radiographic, and blood gas analysis, were examined. Criteria for ARI were based on the International Society of Heart and Lung Transplantation (ISHLT) grading system, in which a PaO2/FIO2 of 200 to 300 indicates ARI. The distribution of PaO2/FIO2 after pulmonary artery intervention, the relation of clinical to laboratory manifestation of ARI, and the correlation among different oxygenation indices were examined. During the study period, 46 patients with congenital heart disease and branch pulmonary artery stenosis were identified. Patient age ranged from 2 months to 25 years (mean 6.2±6 years) and weight ranged from 5 to 86 kg (mean 23±18 kg). ARI was identified in 10 of 46 patients (22%) using clinical criteria and correlated with ISHLT gas exchange criteria. Analysis of RV/FA ratio before (0.82±0.34) and after (0.71±0.22) balloon angioplasty revealed statistically significant decrease (p<0.004). The degree of ARI was graded using ISHLT criteria and correlated with the presence of clinical symptoms (p<0.002). As anticipated, the PaO2/FIO2 ratio had a strong correlation with A-aDO2 (r = 0.75) and SpO2/FIO2 (r = 0.7) and a strong specificity (0.78) to identify patients with clinical ARI. CONCLUSION ARI often can occur after pulmonary artery interventions. The PaO2/FIO2 is a valuable test for identifying patients at risk of developing ARI and can help guide the care of these patients in the postintervention period.