PT  - JOURNAL ARTICLE
AU  - Jack R. Hester
AU  - William J. Korzun
AU  - Lara U. Mabry
TI  - Blood Ammonia Stability Revisited
AID  - 10.29074/ascls.28.3.173
DP  - 2015 Jul 01
TA  - American Society for Clinical Laboratory Science
PG  - 173--177
VI  - 28
IP  - 3
4099  - http://hwmaint.clsjournal.ascls.org/content/28/3/173.short
4100  - http://hwmaint.clsjournal.ascls.org/content/28/3/173.full
SO  - Clin Lab Sci2015 Jul 01; 28
AB  - The instability of ammonia in whole blood has challenged clinical laboratory scientists to develop specimen collection and handling methods that produce reliable results for plasma ammonia concentration. Thirty-eight outpatients' plasma ammonia concentrations were measured after heparinized whole blood specimens from each subject were held for 5, 15, and 30 minutes at room temperature and “on-ice”. The plasma ammonia concentration from whole blood maintained “on-ice” for 5 minutes was designated the “reference value”. Plasma ammonia concentrations from whole blood maintained “on-ice” for 15 or 30 minutes prior to processing were not significantly different from the reference values (15 min., p~0.196; 30 min., p~0.512). Plasma ammonia concentrations from whole blood maintained at room temperature for 5, 15 and 30 minutes prior to processing were also not significantly different from the reference values (p~0.961, 0.610, and 0.948, respectively). These results suggest that reliable plasma ammonia concentrations may be obtained from heparinized whole blood maintained at room temperature for up to 30 minutes.