Autonomic control mechanism of maximal lower body negative pressure application.

  • Selvaraj N
  • Shelley K
  • Silverman D
 et al. 
  • 8

    Readers

    Mendeley users who have this article in their library.
  • N/A

    Citations

    Citations of this article.

Abstract

Autonomic control mechanisms during progressive hemorrhage in humans remain complex and unclear. The present study investigates the autonomic reflexes during maximal application of lower body negative pressure (LBNP) that mimics severe hemorrhage in conscious human subjects (n=10) using analyses of heart rate variability (HRV) and systolic blood pressure variability (BPV) and baroreflex sensitivity. Spectral analysis of HRV included linear power spectral density (PSD), and nonlinear principal dynamic modes (PDM) methods. The maximal LBNP application decreased (P<0.01) the systolic and pulse pressures (PP), root mean square successive differences, normalized high frequency (HF) power of HRV, and transfer function gains at low frequency (LF) and HF bands. Meanwhile, increases (P<0.05) in heart rate, diastolic blood pressure (DBP), LFHRV, LF/HFHRV, and sympathetic activity of HRV using PDM were observed during maximal LBNP tolerance. After the termination of LBNP, no significant changes (P>0.05) were found in all the parameters except DBP and PP between recovery and baseline conditions. Rapid application of maximal LBNP that simulated severe hemorrhage was found to be associated with unloading of baroreflex mediated increased sympathetic reflex.

Author-supplied keywords

  • Blood Pressure
  • Blood Pressure: physiology
  • Heart Rate
  • Heart Rate: physiology
  • Humans
  • Lower Body Negative Pressure

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Nandakumar Selvaraj

  • Kirk H Shelley

  • David G Silverman

  • Nina Stachenfeld

  • Ki H Chon

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free