Effect of Valsalva Maneuver on Circulation Time

¹ From the Cardiology Laboratory of the U. S. Naval School of Aviation Medicine, Pensacola, Florida

Arm-to-tongue circulation times in conjunction with a Valsalva maneuver at 40 mm Hg for 15 seconds were determined in 189 young men. In 112 subjects the 20% sodium dehydrocholate indicator was injected just as the Valsalva maneuver was begun. Circulation times ranged from 13 to 31 seconds. The frequency-distribution was tetramodal, means 14.6 ± 0.25 seconds, 18.8 ± 0.17 seconds, 24.2 ± 0.22 seconds and 29.5 ± 0.37 seconds; within the respective modes lay 9.8%, 42.9%, 35.7% and 11.6% of the sample. In 77 subjects the indicator was not injected until an expiratory pressure of 40 mm Hg had been attained. The range was 14–33 seconds and the frequency-distribution bimodal, means at 14.7 ± 0.18 seconds (9.1%) and 24.6 ± 0.40 seconds (90.9%). It is possible that the lowest mode in both cases may represent subjects with large patent foramina ovalia. The tetramodal nature of the first distribution is probably consequent upon differences in the manner in which the Valsalva maneuver was initiated.