During a cerebrovascular exam, what should you ask the patient to do if equal brachial systolic pressures were obtained and the waveform is below baseline?

The Valsalva maneuver is a specific technique that involves a forced expiration against a closed airway, often employed in cardiovascular assessments to evaluate hemodynamics and vascular response. In the context of a cerebrovascular exam, the maneuver can help assess changes in blood flow and waveforms. When a patient's waveform is below baseline and equal brachial systolic pressures are found, performing the Valsalva maneuver can potentially reveal abnormalities in cerebral circulation and vascular reserve.

This maneuver temporarily increases intrathoracic pressure, which affects venous return and subsequently alters cardiac output. Observing how the waveforms respond during this maneuver can provide valuable insights regarding vascular health, as changes in waveform characteristics may signify either reduced cerebral perfusion or the presence of pathology.

Other options, such as deep breathing, postural changes, or raising the arms overhead, may not specifically provide the same clarity regarding vascular dynamics or may not induce the same level of hemodynamic change that the Valsalva maneuver can. Therefore, it is particularly suited for obtaining meaningful data in this scenario and allows healthcare providers to better understand the vascular condition of the patient.