Influence of psychomental stress level on the preoperative adjustment of plasma viscosity

Patients suffering from one or more of the cardiovascular occlusive diseases have an increased risk of intraoperative thromboembolic or ischemic complication. Hemorheological factors may influence the risk of occurence of these complications. We tested in a prospective study the impact of preoperative mental stress on hemorheological parameters of 22 patients undergoing surgery without cardiovascular disease, compared to a group of 10 healthy probands without imminent operation. We measured endocrinological stress parameters, hematocrit, plasma viscosity, and plasma protein composition the evening before the observed night and the morning before the operation took place. The overnight reduction in stress parameters seen in the probands was not present in the patients. Consequences of this different stress response include a statistically significant increase in hematocrit and plasma viscosity in the patients mainly resulting from a shift of fluids out of the intravascular space. We conclude that the rheological parameters might deteriorate during the preoperative period in patients with increased risk of cardiovascular problems.