Elevated ammonia concentrations: Potential for pre-analytical and analytical contributing factors

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Background: No study has explored the separate contributions of pre-analytical and analytical factors to hyperammonemia. Methods: Laboratory information systems were queried for tests of ammonia concentrations over a 12. month period. Pre-analytic (collection to laboratory receipt) and analytic (laboratory receipt to result) elapsed times were determined. Results: Under routine conditions for 3626 tests, normal and elevated results were similarly distributed if the time from venipuncture to result was <. 120. min. Delays, during analysis performance and in transportation to the laboratory, potentially contributed to hyperammonemia in a small number of samples (. n=. 96, 2.7%). Similar results were obtained from a second hospital with a separate laboratory. Conclusions: Delays, in either transportation to the laboratory after collection or before completion of analysis, have the potential to elevate ammonia concentrations and may cause pseudo-hyperammonemia. Unexpectedly elevated ammonia concentrations need to be evaluated for errors in sampling handling.

Original languageEnglish (US)
Pages (from-to)233-236
Number of pages4
JournalClinical Biochemistry
Volume47
Issue number16-17
DOIs
StatePublished - Nov 1 2014

Fingerprint

Ammonia
Hyperammonemia
Clinical Laboratory Information Systems
Phlebotomy
Selection Bias
Information systems
Sampling

Keywords

  • Analysis delay
  • Post-analytic
  • Pre-analytic
  • Pseudohyperammonemia
  • Transportation delay

ASJC Scopus subject areas

  • Clinical Biochemistry

Cite this

@article{028e659f93374bfe8874e3b30d172f79,
title = "Elevated ammonia concentrations: Potential for pre-analytical and analytical contributing factors",
abstract = "Background: No study has explored the separate contributions of pre-analytical and analytical factors to hyperammonemia. Methods: Laboratory information systems were queried for tests of ammonia concentrations over a 12. month period. Pre-analytic (collection to laboratory receipt) and analytic (laboratory receipt to result) elapsed times were determined. Results: Under routine conditions for 3626 tests, normal and elevated results were similarly distributed if the time from venipuncture to result was <. 120. min. Delays, during analysis performance and in transportation to the laboratory, potentially contributed to hyperammonemia in a small number of samples (. n=. 96, 2.7{\%}). Similar results were obtained from a second hospital with a separate laboratory. Conclusions: Delays, in either transportation to the laboratory after collection or before completion of analysis, have the potential to elevate ammonia concentrations and may cause pseudo-hyperammonemia. Unexpectedly elevated ammonia concentrations need to be evaluated for errors in sampling handling.",
keywords = "Analysis delay, Post-analytic, Pre-analytic, Pseudohyperammonemia, Transportation delay",
author = "Hashim, {Ibrahim A.} and Cuthbert, {Jennifer A.}",
year = "2014",
month = "11",
day = "1",
doi = "10.1016/j.clinbiochem.2014.08.013",
language = "English (US)",
volume = "47",
pages = "233--236",
journal = "Clinical Biochemistry",
issn = "0009-9120",
publisher = "Elsevier Inc.",
number = "16-17",

}

TY - JOUR

T1 - Elevated ammonia concentrations

T2 - Potential for pre-analytical and analytical contributing factors

AU - Hashim, Ibrahim A.

AU - Cuthbert, Jennifer A.

PY - 2014/11/1

Y1 - 2014/11/1

N2 - Background: No study has explored the separate contributions of pre-analytical and analytical factors to hyperammonemia. Methods: Laboratory information systems were queried for tests of ammonia concentrations over a 12. month period. Pre-analytic (collection to laboratory receipt) and analytic (laboratory receipt to result) elapsed times were determined. Results: Under routine conditions for 3626 tests, normal and elevated results were similarly distributed if the time from venipuncture to result was <. 120. min. Delays, during analysis performance and in transportation to the laboratory, potentially contributed to hyperammonemia in a small number of samples (. n=. 96, 2.7%). Similar results were obtained from a second hospital with a separate laboratory. Conclusions: Delays, in either transportation to the laboratory after collection or before completion of analysis, have the potential to elevate ammonia concentrations and may cause pseudo-hyperammonemia. Unexpectedly elevated ammonia concentrations need to be evaluated for errors in sampling handling.

AB - Background: No study has explored the separate contributions of pre-analytical and analytical factors to hyperammonemia. Methods: Laboratory information systems were queried for tests of ammonia concentrations over a 12. month period. Pre-analytic (collection to laboratory receipt) and analytic (laboratory receipt to result) elapsed times were determined. Results: Under routine conditions for 3626 tests, normal and elevated results were similarly distributed if the time from venipuncture to result was <. 120. min. Delays, during analysis performance and in transportation to the laboratory, potentially contributed to hyperammonemia in a small number of samples (. n=. 96, 2.7%). Similar results were obtained from a second hospital with a separate laboratory. Conclusions: Delays, in either transportation to the laboratory after collection or before completion of analysis, have the potential to elevate ammonia concentrations and may cause pseudo-hyperammonemia. Unexpectedly elevated ammonia concentrations need to be evaluated for errors in sampling handling.

KW - Analysis delay

KW - Post-analytic

KW - Pre-analytic

KW - Pseudohyperammonemia

KW - Transportation delay

UR - http://www.scopus.com/inward/record.url?scp=84908700803&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84908700803&partnerID=8YFLogxK

U2 - 10.1016/j.clinbiochem.2014.08.013

DO - 10.1016/j.clinbiochem.2014.08.013

M3 - Article

C2 - 25175939

AN - SCOPUS:84908700803

VL - 47

SP - 233

EP - 236

JO - Clinical Biochemistry

JF - Clinical Biochemistry

SN - 0009-9120

IS - 16-17

ER -