Bleeding complications during renal replacement therapies can be attributed
to coagulation system and platelet function alterations in uremia, and the
application of heparin in extracorporeal circulation. Small protein losses
during hemofiltration are always described, however the high molecular wei
ght of coagulation factors should significantly prevent their removal durin
g hemofiltration. To exclude degradation of coagulation factors under condi
tions of spontaneous ultrafiltration, the hemofiltrate of 40 patients with
acute renal failure (treated with continuous venovenous hemofiltration, CVV
H) was sampled from the filtrate line after 1 h from the beginning of treat
ment and in 5 patients also after 12 and 24 h. Samples were investigated wi
th human factor deficient plasma (VII, X, Xl, XII) from donors with a conge
nital deficiency and with human plasma depleted of factor V, VIII, IX, and
protein S and C. Factor XIII was detected photometrically. Subsequently the
presence of factor- XIII and -VII activity was investigated in plasma and
hemofiltrate from 16 patients treated with intermittent hemofiltration befo
re (plasma) and after (plasma, hemofiltrate) therapy These patients also su
ffered from acute renal failure and needed renal replacement therapies. Qua
lify control was carried out with a buffer solution (<1% activity in the as
says according to recommended protocols). Results: Facfor-V, -VIII, -IX, -X
, -XI, and -XII activity, and protein C and S could not be defected in the
hemofiltrate from continuous hemofiltration. Factor-VII and -XIII activity
was present in the hemofiltrate (mean activity in CVVH: 1.93% for factor VI
I and 6.9% far factor XIII, mean activity in intermittent hemofiltration: <
1% for factor-VII and 7.3 % for factor-XIII). Three were no significant dif
ferences (Student's t-test) in plasma activity before and after intermitten
t hemofiltration of factor VII (44 vs. 47%, p = 0.39) and factor XIII (44 v
s. 52%, p = 0.24). The presence of factor-VII and -XIII activity in the hem
ofiltrate cannot influence plasma activities in intermittent hemofiltration
. Rapid new synthesis and short half-life should neutralize these effects.
Elimination of coagulation factor-XIII activity should be excluded by the n
ext generation of highly permeable membranes and on-line hemodiafiltration.