Which vital sign is primarily assessed using a sphygmomanometer?

The vital sign primarily assessed using a sphygmomanometer is blood pressure. This instrument measures the force of blood against the walls of the arteries, providing a crucial indication of cardiovascular health. Blood pressure readings include two numbers: systolic and diastolic pressure, which represent the pressure during heartbeats and between heartbeats, respectively. Accurately measuring blood pressure is essential in monitoring a patient's overall health, diagnosing conditions such as hypertension, and guiding treatment decisions.

In contrast, heart rate is measured using a stethoscope or pulse oximeter, temperature is assessed with a thermometer, and respiratory rate is typically counted manually or with a respiratory monitor. Each of these vital signs is important, but the sphygmomanometer specifically provides the measurement for blood pressure.