A nurse is performing cardiopulmonary resuscitation (CPR) for an adult client who is unresponsive. The nurse should evaluate the client's circulation by palpating which of the following pulses?

Choice A Reason: This is incorrect because a decreased level of consciousness is a late sign of shock, not an early one. Decreased level of consciousness indicates that the brain is not receiving enough oxygen and blood flow, which can lead to irreversible damage and death.

Choice B Reason: This is correct because increased respiratory rate is an early sign of shock, indicating hypoxia. This finding indicates that the client is experiencing hypoxia, which is a lack of oxygen in the tissues and organs. Hypoxia is a common and early sign of shock, which is a condition where the body's vital organs do not receive enough blood

flow and oxygen due to low blood pressure, low cardiac output, or low blood volume. The client's respiratory rate increases as a compensatory mechanism to increase oxygen intake and delivery.

Choice C Reason: This is incorrect because hypotension is a late sign of shock, not an early one. Hypotension indicates that the blood pressure is too low to maintain adequate perfusion and oxygenation to the vital organs.

Choice D Reason: This is incorrect because anuria is a late sign of shock, not an early one. Anuria indicates that the kidneys are not receiving enough blood flow and oxygen, which can result in acute kidney injury or failure.

Choice a) is incorrect because troponin is not an enzyme, but a protein. Enzymes are molecules that speed up chemical reactions in the body. Troponin does not have this function.

Choice b) is correct because troponin is a protein that binds to calcium and regulates the contraction of heart muscle fibers. When the heart muscle is injured, such as in a myocardial infarction, troponin leaks into the bloodstream and can be detected by a blood test. The higher the level of troponin, the more severe the damage to the heart.

Choice c) is incorrect because troponin does not help transport oxygen throughout the body. That function is performed by hemoglobin, which is a protein found in red blood cells.

Choice d) is incorrect because troponin is not a lipid, but a protein. Lipids are fats that are used for energy storage and cell membrane formation. Troponin does not have these roles.