Performing a CBC on the Cell-Dyn Hematology Analyzer - Complete Guide

Introduction to the Cell-Dyn Hematology Analyzer

The Cell-Dyn hematology analyzer is an automated blood cell counter used to perform complete blood counts (CBCs) and white blood cell differentials. It utilizes multiple technologies including impedance, laser light scatter, and fluorescence to provide a complete hematologic profile from a small sample of whole blood. The Cell-Dyn offers excellent consistency, accuracy, and reliability for high-volume hematology labs.

Principle and Technology of the Cell-Dyn Hematology Analyzer

The Cell-Dyn uses several principles and technologies to analyze blood samples:

• Impedance - Cells passing through the aperture change the electrical resistance between the electrodes, allowing red blood cells, platelets, and white blood cells to be counted and sized.
• Light scatter - Lasers beam light through the cells, and sensors measure forward scatter (cell size) and side scatter (cell complexity/granularity). This differentiates cell types.
• Fluorescence - Reagents stain nucleic acids and allow differentiation of cell populations based on fluorescence intensity.
• Hydrodynamic focusing - Sheathes the sample cells in a stream of diluent to provide uniform cell flow past the aperture.

These technologies provide accurate and reliable results for all common hematology parameters and leukocyte differentials in just over a minute.

Running a CBC on the Cell-Dyn

Here is an overview of the steps to run a CBC on the Cell-Dyn hematology analyzer:

1. Collect a well-mixed anticoagulated whole blood sample in a lavender top (EDTA) tube.
2. Type the patient information into the analyzer using the touch screen.
3. Mix the blood sample well by gentle inversion and load it onto the sample tray.
4. The instrument will aspirate the sample, dilute and split it, then analyze it using the multiple technologies.
5. Results are displayed on the screen within 1 minute and 30 seconds.
6. The 21 parameter CBC includes:
   • White blood cell (WBC) count
   • WBC differential including lymphocytes, monocytes, neutrophils, eosinophils, basophils
   • Red blood cell (RBC) count
   • Hemoglobin
   • Hematocrit (Hct)
   • Mean corpuscular volume (MCV)
   • Mean corpuscular hemoglobin (MCH)
   • Mean corpuscular hemoglobin concentration (MCHC)
   • Red blood cell distribution width (RDW)
   • Platelet count
   • Mean platelet volume (MPV)
7. Results are printed out or automatically uploaded to the laboratory information system (LIS).
8. Any abnormal results are flagged for review.

Quality Control and Maintenance

To ensure accurate results, the Cell-Dyn must be maintained according to the manufacturer's instructions:

• Daily quality control with normal, abnormal, and RBC linearity controls.
• Weekly cleaning of the ultrasound transducer and apertures.
• Routine replacement of reagents and diluents.
• Annual preventive maintenance including calibration and verification.

Proper maintenance minimizes downtime and reduces errors due to factors like blocked apertures, expired reagents, or improper calibration.

Interpreting Cell-Dyn CBC Results

When interpreting Cell-Dyn CBC results, key parameters to review include:

White Blood Cell Count

• High WBCs >11,000/uL may indicate infection, inflammation, leukemia, etc.
• Low WBCs <4,000/uL may indicate bone marrow failure, chemotherapy toxicity, etc.

WBC Differential

• High neutrophil % and count indicates bacterial infection, inflammation, stress.
• Low neutrophil % suggests neutrophil dysfunction or bone marrow disorders.
• High lymphocyte % seen in viral infections like mononucleosis.
• High eosinophil % indicates allergies, parasitic infections, leukemia, etc.
• High monocyte % suggests chronic infection or inflammation.
• High basophil % supports leukemia or allergic disorders.

RBC Parameters

• Low RBC count, hemoglobin, and hematocrit indicates anemia.
• High RBC parameters suggests polycythemia vera.
• Low MCV and MCH indicates microcytic anemia (iron deficiency).
• High MCV and MCH indicates macrocytic anemia (B12/folate deficiency).
• High RDW along with anemia indicates greater variation in RBC size.

Platelet Count

• Low platelets <150,000/uL indicates thrombocytopenia.
• High platelets >450,000/uL suggests thrombocytosis.

Abnormal results should be correlated with the patient history and clinical presentation. Additional testing may be warranted.

Advantages of the Cell-Dyn Hematology Analyzer

The Cell-Dyn hematology analyzer provides a number of benefits for high-volume hematology labs:

• Reliability - Uses proven technologies to provide consistent, accurate results time after time.
• Efficiency - Provides a 21-parameter CBC from just a small blood sample in just over 1 minute.
• Automation - Load samples and see results automatically without much hands-on time.
• Workflow - Seamless LIS connectivity allows automated results reporting.
• Flagging - Identifies abnormal results and blasts or atypical cells if present.
• Storage - Large data storage capacity for patient results.
• Service - Excellent manufacturer service and support.

By providing fast, reliable CBC results, the Cell-Dyn improves workflow and productivity in busy hematology labs.

Limitations of the Cell-Dyn Hematology Analyzer

While the Cell-Dyn is an excellent hematology analyzer, there are some limitations:

• High initial cost and significant maintenance expenses.
• Requires daily QC and trained staff to operate and maintain.
• Does not provide a blood smear; technologist review is still required.
• Workflow can be impacted if the instrument is down for maintenance/repair.
• Reagents, diluents, and waste disposal increase the operating costs.
• Low sample volume (199 μL) may not be optimal for some pediatric patients.

When weighing the pros and cons, for high-volume labs running 24/7 the productivity and efficiency gains of the Cell-Dyn generally outweigh the higher operating costs.

Summary

The Cell-Dyn hematology analyzer utilizes impedance, light scatter, and fluorescence technologies to provide a 21-parameter CBC from a small sample of whole blood in just over a minute. With excellent reliability, automation, and workflow capabilities, the Cell-Dyn improves efficiency and productivity in busy hematology labs running high test volumes. However, the high purchase price, maintenance, and operating costs can be limiting factors. Overall, the Cell-Dyn allows labs to provide physicians with rapid, reliable CBC results to aid in patient diagnosis and management.

FAQs

What is a hematology analyzer?

A hematology analyzer is a medical laboratory instrument used to perform a complete blood count (CBC). It analyzes the cellular components of blood, including red blood cells, white blood cells, and platelets.

What parameters does the Cell-Dyn hematology analyzer measure?

The Cell-Dyn provides a 21-parameter CBC including the white blood cell count and differential, red blood cell count, hemoglobin, hematocrit, and platelet count. It also measures mean corpuscular values, red cell distribution width, and mean platelet volume.

How long does it take to run a CBC on the Cell-Dyn?

One of the advantages of the Cell-Dyn is its speed. It can provide a full 21-parameter CBC with differential from a small blood sample in just over one minute.

Does the Cell-Dyn produce blood smears?

No, the Cell-Dyn uses impedance, light scatter, and fluorescence technologies so it does not create blood smears. A medical technologist still needs to review a peripheral smear for abnormal results.

How often does the Cell-Dyn hematology analyzer need maintenance?

The Cell-Dyn requires daily quality control, weekly cleanings, routine replacement of reagents, and annual preventive maintenance and calibration to remain accurate and minimize downtime.