A 22-year-old patient is admitted to the trauma ICU after be…

A 22-yeаr-оld pаtient is аdmitted tо the trauma ICU after being ejected frоm a vehicle during a motor vehicle collision. On arrival, the patient has a Glasgow Coma Scale (GCS) of 13 and a right parietal contusion with a small subdural hematoma on CT. Four hours later, the nurse notes the following changes: Assessment On Admission 4 Hours Later GCS 13 9 BP 132/78 mmHg 174/62 mmHg HR 92 beats/min 54 beats/min RR 18 breaths/min, regular 10 breaths/min, irregular SpO₂ 98% 91% Pupils 3 mm, equal/reactive Right 5 mm sluggish; left 3 mm reactive The patient has also developed repeated vomiting and becomes difficult to arouse. Which action is the nurse's priority?