A 25-year-old victim of a road accient complains of chest pain, dyspnea. Objectively: the patient is in a grave condition, Ps- 120/min, AP- 90/70 mm Hg.There is pathological mobility of fragments of III-V ribs on the right. Percussion reveals a box sound over the right lung, breathing sounds cannot be auscultated on the right. What examination should be administered in the first place?