The spouse of an older client experiencing delirium is at the client's bedside. The nurse is providing an update to the spouse regarding the client's plan of care. Which of the following responses by the spouse indicates a need for further teaching?

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.

A. Pooling of blood and edema around the eyes: Basilar skull fractures can lead to leakage of cerebrospinal fluid (CSF) into the surrounding tissues, resulting in periorbital ecchymosis, also known as raccoon eyes, due to pooling of blood and edema around the eyes. This finding is characteristic of basilar skull fractures and is caused by disruption of the meninges and subsequent CSF leakage into the soft tissues of the face.

B. Ability to recall how the injury occurred: Memory loss regarding the events surrounding the injury, known as post-traumatic amnesia, is common with basilar skull fractures. This amnesia occurs due to the impact of the injury on the brain and may involve retrograde amnesia (loss of memory of events leading up to the injury) and anterograde amnesia (loss of memory of events occurring after the injury).

C. Bruising over the mastoid process: Bruising over the mastoid process, known as Battle sign, is associated with basilar skull fractures. Battle sign results from blood accumulation (hematoma) in the mastoid region behind the ear due to fracture-related injury to the middle meningeal artery or other blood vessels. This finding typically develops 24-48 hours after the injury.

D. Chvostek’s sign: Chvostek's sign is a clinical manifestation of hypocalcemia, not basilar skull fractures. It is elicited by tapping the facial nerve (facial nerve spasm) and is indicative of neuromuscular irritability due to decreased calcium levels. Chvostek's sign is not directly related to basilar skull fractures.