Veränderungen des Blutvolumens während akuter normovolämer Hämodilution mit 5% Albumin oder 6% Hydroxyäthylstärke und intraoperativer Retransfusion

Abstract

Double label measurements of blood volume demonstrated that with the colloids used a surplus of 15% of colloid infusion in relation to blood removal was necessary to generate isovolemia after ANH.

State of the art in fluid and volume therapy

“…Therefore, if blood loss is compensated for to a large extent using pure crystalline solutions, the colloid osmotic pressure in the blood vessel system will drop significantly. Moreover, during major tumor surgeries, considerable quantities of macromolecules -protein and HES -are lost into the interstitial space, the so-called protein [13] or HES shift [14][15][16]. These are losses of protein or HES that can not be explained by surgical bleeding or urine.…”

“…For example, in ovarian cancer patients, in addition to the protein loss resulting from surgical bleeding (1700 ml, 67 g protein loss), a mean intraoperative protein shift of 49 g occurred [13]. In patients with radical hysterectomy, it was shown that 30% of the applied HES molecules left the vascular bed (mean loss via surgical bleeding: 18 g, mean excretion of HES in urine: 18 g, mean HES shift: 30 g) [16]. Both HES or protein loss via surgical bleeding and the shift of protein or HES into the interstitial space reduces the intravascular colloid osmotic pressure, thus, exacerbating edema formation due to extravasation of fluid.…”

“…The most reliable method for investigating the actual volume effect has proved to be direct measurement of blood volume before and after the application of an infusion solution (. Table 2; [8,14,[16][17][18][19][20]). The crucial pharmacodynamic property of the colloids is their relatively large volume effect [8].…”

Cardiovascular response to acute normovolaemic haemodilution in patients with severe aortic stenosis: assessment with transoesophageal echocardiography

“…Following induction of anaesthesia with sufentanil 0.5-0.9 lg.kg ; mean molecular weight, 200 000; 50% substitution degree; C2 ⁄ C6 ratio = 5) was infused through a 16-gauge peripheral catheter, at ratio of 1.15 : 1 to the donated blood to maintain isovolaemia [15]. The blood volume to be removed was calculated according to a standard formula in order to reach a haematocrit value of 28% [16].…”

“…while taking into account extravasation of colloids into the interstitial space [15]. Given a constant circulatory volume, the higher cardiac preload indices indicated that a fraction of the 'unstressed' blood volume reserve was recruited and mobilised into the haemodynamically active circulatory compartment [21].…”