J Clin Pathol Qual Control.  1997 Dec;19(2):289-296.

Laboratory Evaluation of Automatic Coagulation Analyzer STA(R) for the Routine Coagulation Tests

• Kim MJ
• Park Q
• Song KS
• Yang MS
• Shin WC

Abstract

BACKGROUND: The automated coagulation analyzer STA(R) (Diagnostica Stago, Chausson, France) is a random-access, walk-away system based on electromagnetic detection of clot formation. As well as it can perform clot-based, chromogenic and immunologic assays at the same time, it gives a high throughput using primary tubes, which makes it reasonable to use STA(R) as a routine coagulyzer for coagulation. Therefore, this study was performed to evaluate the primary performance for routine coagulation tests.
METHODS
The precision of prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen was determined from those results from normal and abnormal control plasma samples for 10 consecutive days. The test results of PT, aPTT and fibrinogen were compared with those obtained by other two automated coagulation analyzers. To investigate analytical interferences from high lipids, hemoglobin or bilirubin content, we added those interfering materials in vitro and calculated the respective recovery rate. In case of aPTT test, we analyzed the sensitivity to heparin and factor VIII deficiency. We also derived reference value of each test parameter from the results of hemostatically normal individuals.
RESULTS
The precision analysis showed good reproducibility for PT, aPTT and fibrinogen. The results obtained by STA(R) correlated well with those by other analyzers. Especially, the PT results expressed as INR (international normalized ratio) showed excellent agreement with each other. Analytical interferences with lipids, hemoglobin and bilirubin were negligible through wide ranges. The sensitivity of aPTT reagent (STA-PTT-LT(R), Diagnostica Stago, Chausson, France) to heparin was 0.06 U/mL and desired target range for heparin therapy was calculated as 57.3 to 95.5 seconds. The sensitivity of the some aPTT reagent for factor VIII deficiency was approximately 30%. The ranges of reference values for PT, aPTT and fibrinogen were from 11.5 to 14.1 seconds, from 31.6 to 44.8 seconds and from 167 to 427 mg/dL, respectively.
CONCLUSIONS
We concluded that the automated coagulation analyzer STA(R) offers excellent performances for routine coagulation tests in most clinical settings.

MeSH Terms

Bilirubin
Fibrinogen
Hemophilia A
Heparin
International Normalized Ratio
Magnets
Partial Thromboplastin Time
Plasma
Prothrombin Time
Reference Values
Bilirubin
Fibrinogen
Heparin