TY - JOUR
T1 - The hydrostatic pressure indifference point underestimates orthostatic redistribution of blood in humans
AU - Petersen, Lonnie Grove
AU - Carlsen, Jonathan Frederik
AU - Nielsen, Michael Bachmann
AU - Damgaard, Morten
AU - Secher, Niels H
PY - 2014
Y1 - 2014
N2 - The hydrostatic indifference point (HIP; where venous pressure is unaffected by posture) is located at the level of the diaphragm and is believed to indicate the orthostatic redistribution of blood, but it remains unknown whether HIP coincides with the indifference point for blood volume (VIP). During graded (±20°) head-up (HUT) and head-down tilt (HDT) in 12 male volunteers we determined HIP from central venous pressure and VIP from redistribution of both blood using ultrasound imaging of the inferior caval vein (VIPui) and fluid volume by regional electrical admittance (VIPadm). Furthermore, we evaluated whether inflation of medical anti-shock trousers (to 70 mmHg) affected HIP and VIP. Leaving cardiovascular variables unaffected by tilt, HIP was located 7±4 cm (mean±SD) below the 4(th) intercostal space (IC-4) during HUT and was similar (7±3 cm) during HDT and higher (p
AB - The hydrostatic indifference point (HIP; where venous pressure is unaffected by posture) is located at the level of the diaphragm and is believed to indicate the orthostatic redistribution of blood, but it remains unknown whether HIP coincides with the indifference point for blood volume (VIP). During graded (±20°) head-up (HUT) and head-down tilt (HDT) in 12 male volunteers we determined HIP from central venous pressure and VIP from redistribution of both blood using ultrasound imaging of the inferior caval vein (VIPui) and fluid volume by regional electrical admittance (VIPadm). Furthermore, we evaluated whether inflation of medical anti-shock trousers (to 70 mmHg) affected HIP and VIP. Leaving cardiovascular variables unaffected by tilt, HIP was located 7±4 cm (mean±SD) below the 4(th) intercostal space (IC-4) during HUT and was similar (7±3 cm) during HDT and higher (p
U2 - 10.1152/japplphysiol.01175.2013
DO - 10.1152/japplphysiol.01175.2013
M3 - Journal article
C2 - 24481962
SN - 8750-7587
VL - 116
SP - 730
EP - 735
JO - Journal of applied physiology (Bethesda, Md. : 1985)
JF - Journal of applied physiology (Bethesda, Md. : 1985)
ER -