The Venous
System
5r
179
Y
1
nc
Fig.
6.2.3:
Effects of respiratory pressure changes
on
venous pressure in the thoracic vein
(a) and the abdominal vein (b). The modulating effect of respiration is clearly observed.
PVthor
=
thoracic vena cava pressure, Pthor =intrapleural pressure, PV,bd
=
abdominal vena
cava pressure and Pabd
=
intraperitoneal pressure. From Moreno
(1978).
Fig.
6.2.4:
Temporal relation of flow waveforms in the aorta, pulmonary artery,
pulmonary vein and vena cava. From Morgan et al.,
(1966).