Which of the following interventions is most critical in the first 24 hours after a moderate traumatic brain injury?

Choice A rationale

Elevating the head of bed (HOB) to 15-30° promotes optimal cerebral venous drainage, which assists in reducing intracranial pressure (ICP). Maintaining cerebral perfusion pressure is critical in traumatic brain injury (TBI) to prevent secondary injury from ischemia. This specific elevation angle balances ICP reduction with maintenance of adequate cerebral blood flow. Normal ICP ranges from 5-15 mmHg in children.

Choice B rationale

A quiet, low-stimulus environment minimizes external stimuli that can trigger noxious responses and subsequently increase intracranial pressure (ICP) in a child with severe TBI. Sensory input processing requires cerebral energy and can exacerbate existing cerebral edema or injury. Reducing environmental stress supports cerebral metabolic rest and neuroprotection.

Choice C rationale

Monitoring for changes in the level of consciousness (LOC) is the most sensitive indicator of neurological status and potential deterioration in a TBI patient. A declining LOC, assessed using the Glasgow Coma Scale (GCS), can signal increasing intracranial pressure (ICP) or secondary brain injury. Prompt recognition allows for timely medical or surgical intervention to preserve neurological function.

Choice D rationale

Severe TBI increases the risk for post-traumatic seizures due to focal injury, cerebral edema, or hemorrhage disrupting normal cortical electrical activity. Seizure precautions, including padding side rails and ensuring airway safety, are mandatory to prevent injury and manage potential epileptic events. Prophylactic antiepileptic medications may also be initiated based on injury severity.

Choice E rationale

Administering D5W (dextrose 5% in water) as maintenance fluid is generally contraindicated in severe TBI. This hypotonic solution can rapidly shift free water into the injured, often edematous, brain tissue, potentially worsening cerebral edema and increasing intracranial pressure (ICP). Isotonic or hypertonic solutions are preferred to maintain euvolemia and serum osmolality.

Choice A rationale

An oxygen saturation SpO_2 of 88% indicates significant hypoxemia (low blood oxygen), which is the most critical physiological derangement in respiratory distress. Sustained hypoxemia can rapidly lead to cerebral hypoxia, increasing intracranial pressure, and cardiac arrest, necessitating immediate intervention. Normal is ≥ 94-95% in most children.

Choice B rationale

A heart rate of 160 beats per minute in a school-age child (6-12 years) is tachycardia (normal is 75-115 bpm), often an initial compensatory response to hypoxemia and increased work of breathing. While concerning, it is an attempt to maintain cardiac output, making the SpO_2 decline a more immediate life threat.

Choice C rationale

A temperature of 100.4°F is a low-grade fever, which can increase metabolic demand and O_2 consumption, potentially worsening respiratory status. While it warrants management, it is not the most immediate life-threatening sign compared to severe hypoxemia (SpO_2 of 88%). Normal is 97.7°F to 99.5°F.

Choice D rationale

A respiratory rate of 40 breaths per minute in a toddler (1-3 years) is near the upper limit of normal (25-35 bpm) and indicates tachypnea, a compensatory mechanism to improve gas exchange. While significant, it is a sign of compensation, whereas the low SpO_2 suggests decompensation.