Lung-Protective Ventilation for SAH Patients: Are These Measures Truly Protective?

Excerpt

Acute lung injury and acute respiratory distress syndrome (ALI/ARDS) are common in patients with critical neurological illnesses and herald a worse outcome. It has been reported in 15–40 % of patients suffering from an aneurysmal subarachnoid hemorrhage (SAH) [1, 2]. Any type of acute brain injury can trigger ALI/ARDS, but even more so, the systemic inflammatory response syndrome (SIRS) seen in the acute and delayed phases of SAH exposes these patients to this type of catastrophic respiratory deterioration [3]. Furthermore, hemodynamic augmentation has been the mainstay of treatment for vasospasm/delayed cerebral ischemia in patients with SAH and the timing of the initial therapy as well as the utilization of each component (hypertension, hypervolemia, and inotropic enhancement) varies widely [4]. Hypervolemia, stressed cardiac function, and early recourse to blood transfusion can easily lead to pulmonary edema with worse outcomes. But it is easy to understand that in order for the injured and actively ischemic brain to receive adequate oxygen, gas exchange in the lungs must occur optimally [3]. Finally, because nearly a third of mortality after SAH is due to medical and not neurological complications [5, 6], early implementation of strategies to prevent, even partially, the development of ALI/ARDS is primordial. …