[Changes in coagulation physiology and rheology after preoperative normovolemic hemodilution].
OBJECTIVE
In a prospective randomised controlled trial the effect of preoperative normovolaemic haemodilution on coagulation, plasma viscosity and plasma protein levels was examined.


METHODS
50 patients undergoing gastrectomies were investigated (haemodilution group, n = 30; control group, n = 20). In the haemodilution group a haematocrit of 30% was aimed at. Blood was replaced by normovolaemic infusion of 6% hydroxyethyl starch 200/0.5.


RESULTS
Haematocrit, colloid osmotic pressure, total serum protein, serum albumin and platelet count were significantly decreased intra- and postoperatively in the haemodilution group compared with control group (p < 0.01). All of these showed no differences between the two groups on the 7th postoperative day. Global coagulation parameters showed dilutional influences without significant differences between the two groups. Measurements of rheological parameters showed a statistically significant decrease in plasma viscosity in the haemodilution group compared with control group (p < 0.01). Haemodilution led to a marked reduction in the use of homologous blood (1 unit/haemodilution group; 10 units/ control group). The average volume of 6% hydroxyethyl starch 200/0.5 administered per patient was 15.2 ml/kgKM/d (7.6-22.2 ml/kgKM/d) in the haemodilution group and 12.7 ml/ kgKM/d (8.4-17.7 ml/kgKM/d) in the control group.


CONCLUSIONS
Haemodilution induced decreases in plasma coagulation, platelet count and plasma proteins did not cause any functional impairement and may just reflect dilution of these parameters. It seems that infusion of 6% hydroxyethyl starch 200/0.5 in an amount of 10-20 ml/kgKM/d does not result in a relevant decrease in coagulation parameters.
Hensel
M
M
Klinik für Anästhesiologie und Intensivtherapie der Charité, Berlin.
Wrobel
R
R
Volk
T
T
Pahlig
H
H
Kox
W J
WJ
D000328:Adult; D000368:Aged; D001780:Blood Coagulation Tests; D016063:Blood Loss, Surgical / Q000503:physiopathology; D001798:Blood Proteins / Q000378:metabolism; D001803:Blood Transfusion; D001809:Blood Viscosity / Q000502:physiology*; D001810:Blood Volume / Q000502:physiology*; D005260:Female; D005743:Gastrectomy; D006400:Hematocrit; D006438:Hemodilution / Q000379:methods*; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives; D008297:Male; D008875:Middle Aged; D009997:Osmotic Pressure; D011446:Prospective Studies; D012212:Rheology; D012709:Serum Albumin / Q000378:metabolism; D014629:Vagotomy, Proximal Gastric
D001798:Blood Proteins; D006895:Hydroxyethyl Starch Derivatives; D012709:Serum Albumin