The lower pressure
suffices entirely for an adequate fluid removal from
the open abdomen and thus sufficiently prevents retraction
of the wound edges. The urinary output in patients
was lower than expected. The cause supposedly was the
large wound fluid volume, up to 3 l (1,640 ± 1,334 ml) in
some cases, removed by the VAC system during the
first dressing in accordance with the data (2–5 l) reported
[23]. The removed volume then decreased to 825 ±
119 ml before the open abdomen could be closed.