Hemodynamic changes associated with the Valsalva maneuver in normal men and women

The Valsalva maneuver has been studied in 21 normal adult volunteers (10 men and 11 women). Brachial arterial, intraoral, and right atrial pressures were measured and cardiac outputs obtained in all phases of the maneuver by the indicator-dilution technique. Both flow and pressure changes were of greater magnitude in all phases of the maneuver in women than in men. Under the circumstances of our study, indicator-dilution curves seem to be made between 5 and 15 seconds after injection. The gross systolic pressure failed to show the expected drop in 6 of 20 normal subjects pointing up the difficulty of interpreting the bedside Valsalva. As the Valsalva maneuver is prolonged to 25 seconds, the cardiac outputs of the men drift back toward normal to a greater extent than those of women. At the time of release women increased the blood flow by an average of 22 per cent compared to the control, while men returned only to the resting control levels. Under the circumstances of these observations, apparently reliable dye curves which can be used for blood flow calculation can be obtained even though the flow would seem to be changing when the indicator is injected.