A nurse is planning care for a client who has a traumatic brain injury (TBI). Which of the following nursing interventions should be added to the plan of care? (Select All that Apply.)

A) "Vision changes occur when pressure in the eye is increased due to a decrease of aqueous humor." This statement describes a mechanism associated with glaucoma, not cataracts. In cataracts, vision changes occur due to the opacity or cloudiness of the lens, not changes in intraocular pressure.

B) "Vision changes occur when blood vessels leak fluid or blood under a portion of the retina." This statement describes a mechanism associated with retinal diseases like diabetic retinopathy, not cataracts. In cataracts, the lens becomes cloudy, affecting the passage of light through the eye.

C) "Vision changes occur when the cloudy lens alters the passage of light through the eye." This statement is correct. Cataracts cause the lens of the eye to become cloudy, which interferes with the passage of light through the eye. This results in vision changes such as blurred vision, glare, and difficulty seeing in low light conditions.

D) "Vision changes occur when retinal tissue pulls away from the blood vessels in the eye." This statement describes a mechanism associated with retinal detachment, not cataracts. In cataracts, the lens becomes opaque, but the retinal tissue remains intact.

Pulseless electrical activity (PEA) refers to a situation in which an electrocardiogram (ECG) shows electrical activity in the heart, but there is no effective mechanical activity and no palpable pulse. PEA can result from various underlying conditions that impair cardiac function or compromise circulation.

A. Hypertension: Hypertension, or high blood pressure, is not typically a direct cause of PEA. While uncontrolled hypertension can contribute to cardiovascular disease and increase the risk of cardiac events such as myocardial infarction, it is not a direct cause of PEA.

B. Hypovolemia: Hypovolemia, or low blood volume, is a common cause of PEA. Reduced circulating blood volume leads to decreased preload and inadequate filling of the heart chambers, impairing cardiac output. This can result in ineffective cardiac contractions and the development of PEA.

C. Hypoxia: Hypoxia, or inadequate oxygenation of tissues, is a significant cause of PEA. Insufficient oxygen delivery to the myocardium impairs cardiac function and can lead to ineffective cardiac contractions. Without adequate oxygenation, the heart is unable to generate sufficient mechanical force to maintain circulation, resulting in PEA.

D. Hyperkalemia: Hyperkalemia, or elevated levels of potassium in the blood, can cause PEA by disrupting cardiac electrical activity. Excessive potassium ions in the extracellular fluid alter the normal myocardial action potential, leading to cardiac conduction abnormalities and potential arrhythmias, including PEA.

E. Hypernatremia: Hypernatremia, or elevated levels of sodium in the blood, is not typically a direct cause of PEA. While severe hypernatremia can lead to neurological symptoms and dehydration, it does not directly impair cardiac electrical activity or mechanical function to the extent that it causes PEA.

F. Hyperthermia: Hyperthermia, or elevated body temperature, is not typically a direct cause of PEA. While extreme hyperthermia can lead to cardiovascular complications such as heat stroke, it is not a common cause of PEA unless it is associated with severe systemic metabolic derangements.