Background

Background: ARDS is a life-threatening condition of hypoxemic respiratory failure with reduced lung compliance secondary to diffuse alveolar damage. Alveoli are flooded with a protein-rich exudate, leading to multifocal, bilateral pulmonary consolidation. A myriad of direct and indirect conditions predispose patients to ARDS (Table 4.1). Ten percent of ICU patients and 23% of mechanically ventilated patients have ARDS, and the syndrome is likely underdiagnosed in most ICUs. ARDS remains primarily a clinical diagnosis, and its severity is typically graded as mild, moderate, or severe according to the Berlin criteria (Table 4.2).

Preoperative considerations. Patients with trauma, pancreatitis, or sepsis may require urgent or emergent surgery before pulmonary function can be optimized. Many patients with ARDS benefit from higher levels of PEEP to improve oxygenation and decrease atelectrauma. Care should be taken when transferring between transport ventilators and ICU/operating room (OR) ventilators to avoid the loss of PEEP, which can precipitate atelectasis.