We report the case of an unexpected respiratory complication after a surgical treatment of scoliosis during postoperative period in an adolescent patient. This complication results of a vascular compression of the left main bronchus between the aorta and the pulmonary artery, which induces severe atelectasis of left lower lobe. Prolonged non-invasive ventilation with high level of positive end-expiratory pressure prevents aorto-pulmonary compression, allows a pulmonary recruitment associated with a favorable prognostic for the adolescent.