Context Artificial and bioartificial support systems may provide a "bridge"
for patients with severe liver disease to recovery or transplantation.
Objective To evaluate the effect of artificial and bioartificial support systems
for acute and acute-on-chronic liver failure.
Data Sources Randomized trials on any support system vs standard medical therapy
were included irrespective of publication status or language. Nonrandomized
studies were included in explorative analyses. Trials were identified through
electronic searches (Cochrane Hepato-Biliary Group Controlled Trials Register,
Cochrane Library, MEDLINE, EMBASE, and the Chinese Medical Database), bibliographies,
and contact with experts. Searches were conducted of the entire databases
through September 2002.
Study Selection Of 528 references identified, 12 randomized trials with 483 patients
were included. Eight nonrandomized studies were included in explorative analyses.
Data Extraction Data were extracted and trial quality was assessed independently by
3 reviewers (L.L.K., J.L., B.A-N.). The primary outcome measure was all-cause
mortality. Results were combined on the risk ratio (RR) scale. Random-effects
models were used. Sources of heterogeneity were explored through meta-regression
and stratified meta-analyses.
Data Synthesis Of the 12 trials included, 10 assessed artificial systems for acute
or acute-on-chronic liver failure and 2 assessed bioartificial systems for
acute liver failure. Overall, support systems had no significant effect on
mortality compared with standard medical therapy (RR, 0.86; 95% confidence
interval [CI], 0.65-1.12). Meta-regression indicated that the effect of support
systems depended on the type of liver failure (P =
.03). In stratified meta-analyses, support systems appeared to reduce mortality
by 33% in acute-on-chronic liver failure (RR, 0.67; 95% CI, 0.51-0.90), but
not in acute liver failure (RR, 0.95; 95% CI, 0.71-1.29). Compared with randomized
trials, nonrandomized studies produced significantly larger estimates of intervention
effects (P = .01).
Conclusion This review suggests that artificial support systems reduce mortality
in acute-on-chronic liver failure compared with standard medical therapy.
Artificial and bioartificial support systems did not appear to affect mortality
in acute liver failure.