In the case of an unrestrained 2-year-old with a severe closed head injury on mechanical ventilation, what should be increased to improve oxygen levels?

In a scenario involving a 2-year-old with a severe closed head injury who is on mechanical ventilation and exhibiting low oxygen levels, increasing the fraction of inspired oxygen (FiO2) is a valid and effective strategy. FiO2 refers to the percentage of oxygen that is inhaled; by increasing it, you effectively increase the amount of oxygen available to the patient. This is particularly important in cases of severe head injury, where there is a risk of hypoxia due to compromised cerebral blood flow and oxygen delivery to the brain.

Improving FiO2 supports better oxygenation by enhancing the partial pressure of oxygen in the alveoli and, consequently, in the arterial blood. This action is crucial in managing a patient with significant respiratory compromise stemming from head trauma, as maintaining adequate oxygen levels is critical to prevent further neurological damage and ensure overall stability.

Maintaining appropriate oxygenation is essential, especially in the context of head injuries, as cerebral perfusion must be optimized to minimize secondary injury. Although there are other interventions that can also aid in improving oxygenation, such as adjusting tidal volume or PEEP, increasing the FiO2 directly addresses the immediate need for increased oxygen availability in the body.