Autonomic and hemodynamic responses and interactions during the Mueller maneuver in humans.
We compared the responses to a Mueller maneuver maintained for 20 s to effects of an equal period of end expiratory apnea. We measured heart rate, mean blood pressure (BP), central venous pressure (CVP), and sympathetic nerve activity (SNA) in 9 normal humans. The Mueller maneuver was accompanied by a fall in CVP from 5 +/- 1.2 to -13 +/- 3.2 mmHg (P < 0.05). During the first 10 s of Mueller, BP fell from 95 +/- 4.2 to 81 +/- 5.5 mmHg and SNA fell as low as 16 +/- 6% of control (P < 0.05). For the 5 s prior to release SNA increased to 236 +/- 36% (P < 0.05), and BP began to increase. Release of the Mueller resulted in a surge in BP to 104 +/- 5.8 mmHg and suppression of SNA to 61 +/- 48% (P < 0.05). By contrast, there was no fall in BP or CVP during apnea and SNA increased to 188 +/- 24% for the first 5 s. Between 16 and 20 s of apnea SNA was 231 +/- 52% and BP increased from 92 +/- 3.1 to 96 +/- 3.6 mmHg (P < 0.05). Release of apnea resulted in a surge in BP to 105 +/- 3.0 mmHg and suppression of SNA to 30 +/- 12% (P < 0.05). Oscillations in BP and SNA during the Mueller maneuver may contribute to similar oscillations, and hence cardiovascular consequences, in patients with sleep apnea.
Somers
V K
VK
Department of Internal Medicine, University of Iowa College of Medicine, Iowa City 52242.
Dyken
M E
ME
Skinner
J L
JL
D000328:Adult; D001049:Apnea / Q000503:physiopathology; D001341:Autonomic Nervous System / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D002496:Central Venous Pressure / Q000502:physiology; D004562:Electrocardiography; D005260:Female; D005931:Glottis / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D010100:Oxygen / Q000097:blood; D015656:Respiratory Mechanics / Q000502:physiology*; D013564:Sympathetic Nervous System / Q000502:physiology
D010100:Oxygen