The effect of fractionated plasma separation and adsorption on cerebral amino acid metabolism and oxidative metabolism during acute liver failure.
OBJECTIVE
Patients with acute liver failure have a disturbed amino acid metabolism and a compromised oxidative metabolism in the brain. A limited number of clinically neuroprotective interventions are available. This study aimed at assessing the effect of fractionated plasma separation and adsorption (FPSA), an extracorporeal liver support system, on cerebral amino acids and lactate to pyruvate ratio.


METHODS
Seven patients with acute liver failure and high risk of intracranial hypertension were included for cerebral microdialysis and intracranial pressure monitoring. Microdialysate, arterial blood, and venous blood from the jugular bulb were sampled, before and after an FPSA session, and the content of nineteen amino acids, lactate, and pyruvate was determined.


RESULTS
The total amino acid concentration in arterial plasma was not significantly reduced by FPSA (11.2 mM (3.0-26.0 mM) vs. 9.7 mM (2.7-13.6 mM); median with range). The total amino acid content in the microdialysate was 5.6 mM both before and after FPSA and no change in glutamine content was observed in plasma or microdialysate. The content of aromatic amino acids in arterial plasma, but not in microdialysate, was marginally reduced (p<0.05). Arterial lactate concentration and lactate to pyruvate ratio in the microdialysate did not change following FPSA.


CONCLUSIONS
One single treatment session with FPSA had a marginal effect on plasma amino acid composition. We found minimal changes in the amino acids content in the microdialysate, and the lactate to pyruvate ratio was unaffected.
Department of Hepatology, Rigshospitalet, Copenhagen, Denmark. peter.nissen.bjerring@rh.regionh.dk
Peter Nissen
PN
Bjerring
John
J
Hauerberg
Hans-Jørgen
HJ
Frederiksen
Henning Bay
HB
Nielsen
Jens Otto
JO
Clemmesen
Fin Stolze
FS
Larsen
D000328:Adult; D000596:Amino Acids / Q000032:analysis / Q000097:blood*; D054022:Cerebrum / Q000378:metabolism; D015314:Dialysis Solutions / Q000737:chemistry; D005112:Extracorporeal Circulation; D005260:Female; D005973:Glutamine / Q000032:analysis / Q000097:blood; D006501:Hepatic Encephalopathy / Q000097:blood* / Q000503:physiopathology; D006801:Humans; D022124:Hyperammonemia / Q000097:blood / Q000150:complications; D019586:Intracranial Hypertension / Q000150:complications; D007427:Intracranial Pressure; D019344:Lactic Acid / Q000032:analysis / Q000097:blood; D017114:Liver Failure, Acute / Q000097:blood / Q000150:complications / Q000628:therapy*; D008297:Male; D017551:Microdialysis; D008875:Middle Aged; D019289:Pyruvic Acid / Q000032:analysis / Q000097:blood; D016060:Sorption Detoxification; D018709:Statistics, Nonparametric
D000596:Amino Acids; D015314:Dialysis Solutions; D005973:Glutamine; D019344:Lactic Acid; D019289:Pyruvic Acid