A child with a right pulmonary contusion is intubated and ventilated.

In unilateral lung injury (like pulmonary contusion), placing theinjured lung in the dependent positionworsensventilation/perfusion (V/Q) mismatch, as perfusion is gravity-dependent while ventilation is reduced due to contusion. This results inhypoxemia.

“In lung injuries, dependent positioning of the injured lung increases perfusion to poorly ventilated areas, leading to V/Q mismatch and hypoxemia.”

(Referenced from CCRN Pediatric – Direct Care: Pulmonary, Positioning in Ventilated Patients)