The nurse gives the patient the following instructions: "Focus on the far wall and now focus on my pen." The nurse is assessing the

A: To accurately assess for orthostatic hypotension, the initial blood pressure should be measured while the client is supine. This establishes a baseline for comparing subsequent measurements.
B: Placing the client in a sitting position is a subsequent step in the sequence to monitor changes but is not the first action.
C: Determining the client's blood pressure changes after each position is essential but follows the initial supine measurement.
D: Assisting the client into a standing position is also part of the assessment process for orthostatic hypotension but should occur after recording the supine and sitting blood pressures.

A. Decreased plasma volume might cause overall weak pulses but would unlikely cause an absent pulse specifically localized in one or more extremities. Decreased plasma volume generally affects circulation systemically, not selectively in certain limbs.
B. Problems with the heart's electrical conduction system primarily affect the rhythm and rate of the heart but do not directly cause absent pulses in extremities. These issues lead to irregular or abnormal heartbeats, not localized absence of pulses.
C. Shock can result in weak or thready pulses due to poor blood flow, but shock alone would not typically cause a pulse to be completely absent in one extremity while present in others. Shock affects the circulatory system as a whole.

D. A blockage of blood flow is the most likely cause of an absent pulse in one or more extremities. This could be due to atherosclerosis, embolism, or thrombosis, which can obstruct blood flow in specific areas, leading to no detectable pulse in those extremities.