Don't Lose the Lungs for the Brain: Pulmonary Complications After Subarachnoid Hemorrhage

Abstract

pontaneous subarachnoid hemorrhage (SAH) from a ruptured aneurysm is a catastrophic event. Even if the S patient survives the initial hemorrhage and the aneurysm is safely secured, a whole host of systemic sequelae exist that contribute substantially to morbidity after SAH. Pulmonary complications play a major role in this arena. The principal pulmonary complications are acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). The North American-European Consensus Conference formally defined these 2 entities more than 20 years ago to aid in trial design (1). A diagnosis of ALI required 3 criteria: acute arterial hypoxemia (ratio of partial arterial oxygen pressure to fraction of inspired oxygen <300), bilateral infiltrates on chest x-ray, and no clinical evidence of left atrial hypertension. ARDS is ALI but with more severe arterial hypoxemia (ratio of partial arterial oxygen pressure to fraction of inspired oxygen <200).