Pre-Analytics Guidelines – MDC Labs
1. Request Form
To ensure accurate patient identification and reliable test results, please complete the Request Form with clear and legible handwriting.
🔹 Patient Details: Include Age or Date of Birth to apply the correct reference ranges.
🔹 Clinic Information: Enter the physician’s or clinic’s name in the upper right corner.
🔹 Sample Identification: Attach the provided ID number sticker to the sample tube. This ensures the correct identification of patient samples.
2. Sample Collection & Pre-Analytical Conditions
Laboratory investigations contribute up to 70% in diagnosing medical conditions. However, factors like storage, transport, and handling can significantly impact test results.
💡 Key Guidelines:
✅ Use the provided sample collection materials to maintain quality.
✅ Avoid splitting samples when possible, as this increases the risk of patient mix-ups.
✅ Ensure proper sample storage to prevent deterioration.
3. Sample Handling Instructions
Vacutainers & Clotted Samples
🔹 MDC Labs provides high-quality vacutainers and German Sarstedt tubes. These systems:
✅ Minimize hemolysis and reduce hematoma or bleeding after collection.
✅ Offer better handling and improved sample integrity.
💡 Clotting Process: Allow whole blood samples to clot for 20-30 minutes before centrifugation. Incomplete clotting may lead to small clots, which can affect test results.
Blood Collection Guidelines
🔹 EDTA & Citrate Tubes:
✅ Mix immediately (gently shake, do not shake vigorously) to prevent clot formation.
🔹 Leaking Vials:
⚠️ Leaking samples pose risks to both laboratory and non-medical staff. Always use properly sealed containers.
🔹 Citrate Tubes for Coagulation Tests:
✅ Fill to the marked level to ensure accurate dilution and reliable results.
Storage Considerations
📌 Haemolysis Prevention:
Avoid collecting blood after prolonged venous congestion, as this can interfere with multiple tests.
📌 Coagulation Parameters:
🔹 Samples must be tested within 4 hours to prevent inaccurate clotting times.
📌 Complete Blood Count (CBC):
🔹 Delayed processing (>4 hours) may distort cell morphology, affecting differential results.
📌 Microbiology Samples:
🔹 Gonococci, Chlamydia, Mycoplasma, Meningococci, and Anaerobic Germs degrade over time.
✅ Minimize storage time and use special swabs when needed.
📌 PCR Testing (Chlamydia, HCV, HBV, etc.):
✅ Do not open or split vacutainers meant for PCR analysis to avoid contamination.
4. Measurement Tolerances of Applied Methods
Method | Abbreviation | Error Margin |
---|---|---|
Atomic Absorption (Flame) | AAS | ±3% |
Enzyme Immuno-Assay | ELISA, EIA, FIA, LIA, RIA, ECLIA, CLIA | ±15% |
Gas Chromatography | GC | ±3% |
Liquid Chromatography Mass Spectrometry | LC MS | ±5% |
Tandem Mass Spectrometry | MS MS | ±5% |
Quantitative PCR | PCR | ±50% |
Other methods follow industry-standard tolerances. |
5. Specimen Requirements: Tubes & Containers
Tube Type | Cap Color | Capacity | Purpose |
---|---|---|---|
Serum Tubes | Red | 5ml, 8ml | Biochemical, hormonal, immunological tests |
EDTA Tubes | Violet | 2ml, 5ml | Hematology, genetic tests |
Coagulation Tubes | Blue | 2ml, 4ml | Coagulation testing (must be filled properly) |
Heparin Tubes | Green | 4ml | Chromosome analysis |
ESR Tubes | Black | 2ml | Erythrocyte sedimentation rate |
Urine Tubes | Yellow | 10ml | Routine urine analysis |
Urine Containers | – | 30ml | General urine collection |
24-Hour Urine Containers | – | 2000ml | 24-hour urine collection |
Stool Containers | – | – | Stool sample collection |
Swab Containers | – | – | Contains swab with media for microbiology |
Blood Culture Flasks | – | 70ml | Aerobic & anaerobic blood cultures |
Liquid-Based Cytology (ThinPrep) | – | – | Call MDC Labs for orders |
📌 For special collection materials, orders, or clarifications, please contact MDC Labs.
Contact Information: 📞 Phone: +971 50 889 7692 | 📍 Location: MDC Labs – Al Moosa Diagnostic Center