A nurse is preparing the client for an electrocardiogram (ECG). The client asks the nurse what is an electrocardiogram.
Which is the best description for an electrocardiogram?

Choice A rationale

Myopia, or nearsightedness, is when distant objects appear blurry because light rays focus in front of the retina. A Snellen exam result of 20/50 means the client can see at 20 feet what someone with normal vision sees at 50 feet, indicating reduced distance vision. However, this condition does not correlate with the ability to read the Rosenbaum chart, which is for near vision, thus excluding myopia.

Choice B rationale

Normal vision is not indicated by a Snellen exam result of 20/50, as this signifies a visual impairment where the client sees at 20 feet what a person with normal vision sees at 50 feet. Normal vision would be indicated by 20/20 on the Snellen exam.

Choice C rationale

Presbyopia is the age-related loss of the eye's ability to focus on near objects, typically noticeable in people over 40. Although this condition involves difficulty reading at close range, the client's uncorrected Snellen exam result of 20/50 pertains to distance vision, which differentiates presbyopia from the given scenario.

Choice D rationale

Hyperopia, or farsightedness, is when close objects appear blurry because light rays focus behind the retina. The client's ability to read the Rosenbaum chart without difficulty indicates good near vision, while the Snellen exam result of 20/50 reflects reduced distance vision, thus supporting the diagnosis of hyperopia.

Choice A rationale

Pallor refers to the pale appearance of the skin due to decreased blood flow or decreased hemoglobin levels. It is often seen in conditions such as anemia, where there is a reduced number of red blood cells or hemoglobin, leading to a lack of the red-pink tones normally present in healthy skin.

Choice B rationale

Cyanosis refers to a bluish discoloration of the skin and mucous membranes due to inadequate oxygenation of the blood. It is often seen in respiratory or cardiovascular conditions where there is a decrease in oxygen levels. Cyanosis does not describe the absence of red-pink tones from decreased hemoglobin.

Choice C rationale

Jaundice refers to a yellow discoloration of the skin and eyes due to elevated levels of bilirubin in the blood. It is often seen in liver conditions or hemolysis. Jaundice is not related to decreased hemoglobin levels or the absence of red-pink tones in the skin.

Choice D rationale

Erythema refers to redness of the skin caused by increased blood flow to the capillaries in the dermis. It is often associated with inflammation, infection, or skin irritation. Erythema indicates increased blood flow, not decreased hemoglobin levels.