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A nurse is caring for a client who has a traumatic brain injury. The nurse notes that the client has a widening pulse pressure. Which of the following actions should the nurse take?

Choice A Reason: This is incorrect because hypervolemia is a condition of excess fluid volume in the body. A client who has an extensive burn injury is more likely to have hypovolemia, which is a condition of low fluid volume, due to fluid loss from the damaged skin and capillaries.

Choice B Reason: This is incorrect because metabolic alkalosis is a condition of high blood pH and high bicarbonate level. A client who has an extensive burn injury is more likely to have metabolic acidosis, which is a condition of low blood pH and low bicarbonate level, due to increased production of lactic acid and ketones from tissue hypoxia and breakdown.

Choice C Reason: This is correct because low hemoglobin is a common laboratory finding in a client who has an extensive burn injury. Hemoglobin is the protein in red blood cells that carries oxygen. A client who has an extensive burn injury may have low hemoglobin due to hemolysis, which is the destruction of red blood cells, or hemorrhage, which is the loss of blood.

Choice D Reason: This is incorrect because hyperkalemia is a condition of high blood potassium level. A client who has an extensive burn injury may have hyperkalemia in the early phase of injury, due to cell damage and potassium release, but it is usually transient and followed by hypokalemia, which is a condition of low blood potassium level, due to fluid loss and potassium depletion.

Choice A Reason: This choice is incorrect because providing a brightly lit environment may stimulate the client and increase the intracranial pressure. A brightly lit environment is an environment that has a high level of illumination or brightness. It may be used for clients who have depression, seasonal affective disorder, or insomnia, but it does not help to reduce the intracranial pressure.

Choice B Reason: This choice is incorrect because teaching controlled coughing and deep breathing may increase the intrathoracic pressure and increase the intracranial pressure. Controlled coughing and deep breathing are techniques that help to clear the airway and improve lung expansion. They may be used for clients who have respiratory infections, chronic obstructive pulmonary disease, or postoperative complications, but they do not help to reduce the intracranial pressure.

Choice C Reason: This choice is incorrect because encouraging a minimum intake of 2000 mL (67.5 oz) of clear fluids per day may cause fluid overload and increase the intracranial pressure. Fluid overload is a condition in which the body has too much fluid, which can impair the function of the heart, lungs, and kidneys. Therefore, restricting fluid intake and using diuretics may be indicated for clients who have increased intracranial pressure.

Choice D Reason: This choice is correct because elevating the head of the bed 20° may help to improve the venous drainage and decrease the intracranial pressure. As explained above, positioning the client in a semi-Fowler's or high-Fowler's position can facilitate breathing and prevent further complications. However, elevating the head of the bed more than 30° may decrease the cerebral perfusion pressure (CPP), which is the difference between the mean arterial pressure (MAP) and the intracranial pressure (ICP). A normal CPP range is 70 to 100 mm Hg, and a low CPP (<50 mm Hg) can cause cerebral ischemia, herniation, or death. Therefore, elevating the head of the bed to a moderate angle (20°) may be optimal for clients who have increased ICP.