The Annals of Thoracic Surgery, Vol 30, 536-542, Copyright © 1980 by The Society of Thoracic Surgeons
Interstitial fluid pressure changes during cardiopulmonary bypass
ER Rosenkranz, JR Utley, FJ Menninger 3d, WP Dembitsky, AR Hargens and RM Peters
The effects of cardiopulmonary bypass using hemodilution on interstitial
fluid pressure were measured using the Scholander wick technique. In 10
mongrel dogs, interstitial fluid pressure was measured in subcutaneous
tissue, skeletal muscle, stomach, and left ventricle before and during 2
hours of cardiopulmonary bypass. Changes in interstitial fluid pressure
were correlated with plasma colloidal osmotic pressure and duration of
bypass. In subcutaneous tissue and skeletal muscle, interstitial fluid
pressure increased during bypass; it did not change in the stomach.
End-diastolic interstitial fluid pressure in the left ventricle increased
significantly. These increases in pressure were presumably due to an
increase in interstitial water. The rise in interstitial fluid pressure
acts to partially neutralize the fall in plasma colloidal osmotic pressure.