Moderate and severe traumatic brain injury: Case

This boy has severe traumatic brain injury with impending herniation. A Glasgow Coma Scale of 5 after resuscitation places him deep in the severe band, and the unilateral fixed dilated pupil is uncal herniation compressing the third nerve. His hypotension and his low oxygen saturation are secondary brain insults that will double his mortality if not corrected at once, so the resuscitation and the lowering of the intracranial pressure must proceed together. ^[4]

Clinical findings and assessment

The key findings are the Glasgow Coma Scale of 5, the unilateral fixed dilated right pupil, the hypotension, and the borderline oxygen saturation. A score of 5 is severe injury, well below the 8 that mandates intubation, and the fixed dilated pupil is uncal herniation until proven otherwise. The hypotension, with a systolic of 78 mmHg in a 9-year-old, is itself a secondary brain insult, because it lowers the mean arterial pressure and so the cerebral perfusion pressure, and a single hypotensive episode is said to double the mortality. The glucose is normal, which excludes hypoglycaemia as a contributor. ^[6]

The immediate assessment is the structured primary survey. The airway is not protected at a GCS of 5, the cervical spine is presumed injured and immobilised, the breathing is compromised with a saturation of 91 percent, and the circulation is failing with the hypotension. The pupil finding localises the lesion and grades the urgency, and the weight of 28 kilograms is confirmed for the drug doses. ^[4]