LabNotes - Volume 20, No. 1, 2009

Quality Serum Specimens with the Speed of Plasma ' Introducing the BD Vacutainer' Rapid Serum Tube

The need for improved workflow remains at the forefront of efficient laboratory management. This has placed additional emphasis on laboratory resources, both in the private and hospital sectors, to deliver quality services and enhance productivity. In addition, the demands for improved throughput have reiterated the focus on more rapid receipt of test results as well as reduction in preanalytical errors (e.g. hemolysis'a major reason for specimen rejection), which require sample re-draws and re-work, contributing to delays in report time. As such, more and more laboratories are including turnaround time as a key performance indicator of their services. However, many have difficulty in meeting these goals.¹

To address the needs for improved workflow efficiency and turnaround time, BD Diagnostics ' Preanalytical Systems has introduced a new fast-clotting serum blood collection tube in the US'the BD Vacutainer' Rapid Serum Tube (BD RST). The BD RST is a 4mL-draw, 13x100mm plastic sterile blood collection tube with a gel separator and a thrombin additive. The thrombin additive promotes rapid clotting of the blood, allowing the BD RST to be centrifuged five minutes after collection to provide a quality serum specimen that can be sampled directly from the primary tube.

The five-minute clotting time of the BD RST represents a significant reduction in clotting time as compared with traditional serum gel tubes, which typically require a minimum clotting time of 30 minutes. This may result in a time savings of up to 25 minutes, improving laboratory workflow. In addition, in a recent study conducted by BD in the Czech Republic, the combination of the BD RST using a 3-minute centrifuge time on the StatSpin' Express 3 centrifuge led to significantly faster preanalytical turnaround time by an average of 38.5 minutes.² The increased test result turnaround time may potentially lead to more rapid diagnosis and treatment planning, which are vital for patients in many hospital units (e.g. emergency, cardiac, intensive care). Faster patient diagnosis and treatment in the Emergency Department (ED) accelerate discharge or admission, which decrease the overall length of stay in the ED. As a result, the ED can increase patient throughput and reduce patient diversions, all key services for hospitals today.

Clinically Proven Performance

In order to demonstrate the clinical performance of the BD RST, seven clinical studies were conducted to evaluate the BD RST for a wide range of clinical chemistry assays' routine and special chemistry analytes (e.g. cardiac markers, female hormones, thyroid hormones). In addition, selected analytes in immunology were also evaluated (e.g. C3, C4, IgG, IgM). Following blood collection by routine venipuncture, the studies were performed to assess the tube's efficacy and spanned a wide range of patient populations (apparently healthy adult subjects, cardiac papregnant subjects, patients with a range of clinical diagnoses and conditions).

Clinical performance was evaluated on a range of instrument platforms* including:

1. Abbott AxSYM'
2. Bayer ADVIA' Centaur
3. Beckman Coulter Access' 2
4. DPC Immulite'1000
5. Olympus' AU5200'/AU5400'
6. Ortho Clinical Diagnostics VITROS' ECi
7. Ortho Clinical Diagnostics VITROS' 5,1 FS
8. Roche COBAS Integra' 800
9. Roche Modular

Improving a Source of Specimen Rejection

Hemolysis results from the degradation or lysis of red cells in blood samples and continues to be a frequent occurrence in clinical laboratories; prevalence may be as high as 3.3% of routine specimens, accounting for up to 40%-70% of unsuitable specimens. This is more than five times higher than other causes for specimen rejection.³ In addition, the presence of hemolysis may alter laboratory-generated analytical results, possibly causing certain analytes to be increased due to leakage of red cell constituents or interference with the test method.⁴ These issues contribute to increased time to test results and necessitate repeat collection by phlebotomy.

All tubes in the studies were evaluated for hemolysis (trace level or higher). The results demonstrated a significant reduction in hemolysis in the BD RST as compared to a control serum gel tube when specimens were collected via routine venipuncture. The hemolysis rate in the BD RST was 28/1034 samples (2.71%), while the serum gel tube exhibited a rate of 32/579 samples (5.53%). This reduction in hemolysis may improve specimen quality and preclude the need for repeat draws.

Today's demands for improvements in laboratory workflow and turnaround time remain a challenge for healthcare professionals. The reduced clot time of the BD RST can aid in decreasing sample processing time, which may significantly enhance patient throughput. This is particularly vital for units of the hospital in which test results drive important medical decisions on patient treatment.

For inquiries on the BD RST, please contact BD Technical Services at 1-800-631-0174 or contact your local BD Sales Consultant.

* Brands are trademarks of their respective owners.

References

1. Hawkins RC. Laboratory turnaround time. Clin Biochem Rev 2007;28:179-194.
2. Prusa R, Doupovcova J, Warunek D, Stankovic A. Improving laboratory efficiencies through significant time reduction in the preanalytical phase. Clin Chem Lab Med 2009:Accepted for publication.
3. Lippi G, Blanckaert N, Bonini P, Green S, et al. Haemolysis: An overview of the leading cause of unsuitable specimens in clinical laboratories. Clin Chem Lab Med 2008;46:764-772.
4. Sonntag O. Haemolysis as an interference factor in clinical chemistry.
   J Clin Chem Clin Biochem 1986;24:127-139.