Surface Tension and Dilatational Rheology of Blood in Patients Subjected to Cardiological Operations under Conditions of Artificial Circulation

Abstract

Pendant drop and bubble shape methods are employed to study the tensiometric and rheological parameters of blood serum and plasma in 45 patients 49–70 years old subjected to surgical operations under the conditions of artificial circulation because of ischemic heart disease (first group) and heart valve pathology (second group). Blood sampling is performed 1 h before and 12 h after (the first day) the operation, as well as on the 7th postoperative day. Statistically significant changes in the surface tension and viscoelasticity modulus are observed on the 1st day after the operation in both groups, thereby indicating a substantial increase in the content of surfactants in the blood serum. On the seventh day of the postoperative period, a positive dynamics is observed; however, the studied rheological parameters—in particular, viscoelasticity modulus E—at frequencies of 0.1 and 0.01 Hz statistically reliably exceed their preoperative level and do not reach the values characteristic of healthy people. Thus, the pathological deviations of biochemical parameters (contents of glucose, urea, creatinine, albumin, and lipoproteins) that affect blood viscosity are accompanied by substantial changes in the surface tension and dilatational viscoelasticity of blood serum. However, the examined biochemical markers are not dominating predictors for changes in the rheological and tensiometric properties of blood.