What is the first step in the modified Valsalva maneuver?

The modified Valsalva maneuver is used primarily to treat certain types of supraventricular tachycardia (SVT). The first step in this maneuver involves the patient performing a forced expiration, which increases intrathoracic pressure and can help stimulate the vagus nerve, potentially leading to a reduction in heart rate.

Initiating with forced expiration is critical because it creates the necessary physiological changes in the cardiovascular system. When the patient exhales forcefully against a closed airway (typically by closing the mouth and pinching the nose), it can help restore normal heart rhythm by promoting reflex mechanisms that affect heart rate and conduction pathways.

Other options, like positioning the patient flat or raising their legs, may be part of the overall process to support the maneuver or optimize conditions but are not the first action to initiate the modified Valsalva approach. Measuring heart rate is important for monitoring but does not play a role in executing the maneuver itself.