Effect on the Diuresis of Simultaneously Applied Infusions of Hypotonic Liquid into the Portal Vein and of Hypertonic Liquid into the Superior Vena Cava

Abstract

Lindahl, F., Lund, B., Boas, B. & Schmidt, A. Effect on the diuresis of simultaneously applied infusions of hypotonic liquid into the portal vein and of hypertonic liquid into the superior vena cava. An attempt at demonstrating the existence of an intraportal osmoregulatory system in man. Scand. J. Gastroent. 1974. 9, 133-136.

In an attempt at demonstrating the existence of an intraportal osmoregulatory system in man, catheters were introduced prior to surgery, via the umbilical vein into the portal vein in 15 patients. After surgery, 100 ml of a hypotonic solution was infused via the catheter and. in order to obtain isosmolarity in the right atrium after mixing, the same volume of hypertonic NaCl was infused via the catheter in the superior vena cava. A 1.2% change in the osmolarity in the left portal vein did not bring about any significant changes in the diuresis within six 15-minute-periods. Each patient served as his own control and changes in the diuresis were considered relevant indicators of effect. Consequently, it was concluded that a possible existence of an intraportal osmoregulatory system could not be considered to be of any physiological significance.

Key-words::

• Hepatic osmoregulator
• osmoconcentration
• osmoregulation