Q: Hypoxia is an early sign of pulmonary contusion. True or False?

Answer:  False 

In the early presentation of pulmonary contusion, hypoxia is rare unless a patient is affected with severe bilateral chest trauma. It takes about 24 to 48 hours before hypoxia starts to manifest due to the following development of ARDS. Also, pain from severe chest wall trauma affects patient ability to ventilate and contributes to hypoxemia.



Reference:

Miller PR, Croce MA, Kilgo PD et al. 'Acute respiratory distress syndrome in blunt trauma: identification of independent risk factors.' Am Surg 2002;68:845-50