Unilateral pulmonary edema is unusual in presentation and is mainly seen in the re-expansion phase after pneumothorax, systemic-to-pulmonary shunt, parenchymal lung disease, and unilateral sympathectomy. The mechanisms of unilateral pulmonary edema include an increase in capillary blood flow, reduced surfactant, rapid re-expansion of a collapsed lung, and disruption of venular post-capillary sphincter function after sympathectomy.1–3
http://onlinelibrary.wiley.com/doi/10.1111/j.1527-5299.2005.03861.x/full