Sample Quality Assurance

Transcription

1 Sample Quality Assurance Phlebotomy Association of Ireland AGM 2012 Julie Riordan BSc, HDip Arts, MSc, F.A.M.L.S.

2 Talk Outline Quality Assurance (QA) Preanalytical Variables (PAVs) & Errors (PAEs) Effects of PAEs Solutions

3 What is Quality Assurance (QA)? Maintenance of a desired level of quality in a service or product. Planned and systematic activities implemented in a quality system so that quality requirements for a product or service will be fulfilled 1. Systematic measurement, comparison with a standard, monitoring of processes and an associated feedback loop that confers error prevention 1. "Fit for purpose "Right first time" 70-85% of clinical decisions are based upon information derived from lab test result ( 1

4 QA In the Total Testing Process

5 Pre-analytical Phase

6 Pre-analytical Error Errors that occur due to variables within the pre-analytical phase that affect the quality of a specimen before analysis.

7 TTP Error Frequency Pre-analytical errors Plebani M. Exploring the Iceberg of Errors in Laboratory Medicine. Clinica Chimica Acta. 2009;404:16-23.

8 Pre-analytical Error Can account for up to 93% of the errors currently encountered during the total diagnostic process review of multiple studies also showed similarly high results 2. Overall, insufficient specimen quality and quantity may account for over 60% of diagnostic process preanalytical errors 3. 1 Preanalytical variability: The dark side of the moon in Laboratory testing. G.Lippi et al. Clin CHem Lab Med, Jan 2006; 44(4): Errors in laboratory Medicine. M Bonini et al. Clin Chem 2002; 48: Preanalytic Error Tracking in a Laboratory Medicine Department:Results of a 1-year Experience.G.Lippi et al.clin Chem,Jul 2006; 52:

9 Pre-analytical Variables Uncontrollable PAVs Controllable PAVs

10 Uncontrollable PAV s Biological variability Environmental conditions Smoking Postural changes Diet (fasting/non-fasting) Medication Physical activity Stress Endogenous Interferences Lipaemic, Jaundice

11 Patient Preparation & Education

12 Controllable PAV s Specimen Collection Specimen Labelling Specimen Transport Specimen Handling Specimen Processing

13 Common Sources of PAVs & PAEs Labelling Poor phlebotomy technique Haemolysed samples Clotted samples Inadequate mixing of tubes Empty/Incorrect tubes Expired tubes Insufficient sample volumes Venipuncture site Contamination Inappropriate transport and storage conditions Inappropriate blood to tube additive ratio

14 Specimen Collection - Patient Identification & Labelling Bedside/Patient side labelling is essential No Addressograph labels No pre-labelling Missing test requests Mislabelled Incorrectly Labelled Unlabelled Manual / handwritten Labelling system Electronic Labelling System Blood Transfusion Acceptance Local Laboratory/Hospital Labelling policy

15 Specimen Collection Sample Container Type & Quality Incorrect tube type Empty tube Missing Tube Specimen tubes = Lab Reagents Expiration Dates Stability Issues Tube Mixing

16 Specimen Collection Order of Draw 1. Blood Culture Bottles 2. Sodium Citrate tubes Coagulation 3. Sodium Citrate tubes ESR 4. Serum tubes / dry and gel separator 5. Heparin tubes 6. All other Anticoagulants EDTA 7. Flouride/Oxalate tubes - Glucose

17 Specimen Collection Phlebotomy Procedure Venipuncture site Needle caliber/gauge Adequate sample mixing Tourniquet Time Fist clenching/grip balls

18 Tourniquet Time Haemolysis Potassium and LFT's Hemoconcentration - Increase in various chemistry analytes, including serum protein, potassium and lactic acid. Should not be left in situ for more than one minute Tourniquet >1min = up to 20% increase in haemolysed samples.

19 Clenching & Grip balls Potassium release from Myocytes Fist Clenching: Widely unrecognised cause of pseudohyperkalaemia. Gambino et al. Ann Clin Biochem 2008; 46:177 :- Potassium results >5.3mmol/L reduced from 3.7% to 2.4% with removal of this practice. Bailey et al. Ann Clin Biochem 2008; 00:1-4 :- Percentage fall also. Grip/Squeeze Ball: Gambino et al. Ann Clin Biochem 2008; 46:177 :- Elimination resulted in decrease in potassium results >5.3mmol/L from 10.5% to 2.6%

20 Sample Volume Second most common cause of rejection Insufficient Tube additives / anticoagulants Ensure maximum to correct ratio, until vacuum exhausted. Underfilled Haemolysis, changes in cell morphology, prolonged coagulation times. Overfilled delayed clotting/fibrin formation, inadequate coagulation and creation of microclots. Anaemia

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22 Sample Transport Location Length of transport Transport environment/conditions Temperature, vibration/aggitation. Pneumatic Tube System Blood gas samples, CLL Patient samples Portering

23 Sample Storage & Stability Centifugation protocols Length Temperature Light Freeze-thaw cycles

24 Sample Stability From

25 Sample Timing Time related concentration changes. Stability of analytes. Diurinal Variation / Circadian rhythm. Fasting or Non-Fasting. Pre- or post- medication (I.V. Antibiotics, TDM). Pre- or post- Fluids. Follow timing protocols

26 Sample Contamination Haemolysis Anticoagulants I.V. Fluids T.P.N. Bacteria

27 Sample Contamination - Haemolysis Red Cell destruction and Haemoglobin pigment release. 60% of rejected samples 1 Pseudohyperkalaemia/Normokalaemia, LFT s, Coagulation studies. Preanalytical Reasons: Low Ambient Temperatures Prolonged Transport times Prolonged Tourniquet use Use of fist clenching/grip ball Haematoma site draw Small gauge needle Vigorous shaking or mixing Slow blood flow Skill/training issues Fragile Veins Multiple Medical Conditions 1 Carrero P, Servidio G, Plebani M. Haemolysed specimens: a reason for rejection or a clinical challenge? Clin Chem 2000; 46:

28 Sample Contamination - Haemolysis Burns et al (18) - significantly higher rate of haemolysis in samples collected by phlebotomists who had not had formal training and certification. Bailey et al (19) Suggests that when more than 9% of potassium results are above the reference range, the possibility of a pre-analytical problem should be considered.

29 Sample Contamination - Anticoagulants Heparin: - Coagulation Studies K2 or K3 EDTA samples: - Potassium - Calcium - ALP, Mg. Lithium Heparin - Lithium!

30 Sample Contamination I.V.Fluid Always use alternate arm if possible. Wait for I.V. to be stopped for at least 5 (10 for KCL & Heparin) minutes prior to venipuncture. Note on request form Effects: Saline :- All results diluted + Na&Cl KCL :- potassium + Chloride Dextrose :- All results diluted + Glucose

31 Sample Contamination T.P.N. SVPH common problem as patients on T.P.N for extended time periods. Lipaemia - Elevated lipids Pseudohyponatraemia Note on request form

32 Sample Contamination - Bacteria Uncommon Bacteria within sample tube Blood samples / Blood films Blood cultures Aseptic / Infection control procedures

33 Effects of PAV/PAEs Efficiency Patient safety/outcome Wrong diagnosis Unnecessary treatment / procedures / surgery Patient Mistrust Reputations Cost/financial

34 Effects of PAE/PAVs Plebani M, Carraro P. Mistakes in a Stat Laboratory: Types and Frequency. Clinical Chemistry Plebani M, Carraro P. Errors in a Stat Laboratory: Types and Frequencies 10 years later. Clinical Chemistry

35 Cost of PAE Redraw Re-analysis Instrument downtime labour/parts/repair. Patient treatment/los costs Additional procedures/surgery Time and labour re dealing with issues relating to preanalytical errors. Legal costs

36 Solutions Quality Control & Assurance Quality Management System Metric for tracking errors and setting targets Error Tracking and monitoring Define and implement quality indicators and outcome measures. Reporting systems Quality Products/reagents QA Programs Q-Tracks

37 Q-Tracks Q-TRACKS monitors reach beyond the testing phase to evaluate the quality of processes both within and beyond the laboratory that can impact test results and patient outcomes.

38 Q-Tracks Q-Track QT1 - Patient Identification Accuracy Performance Indicators Wrist Band Error rate (%) Breakdown of Wristband Error Types (%) QT2 Blood Culture Contamination Total Contamination Rate (%) Neonate Contamination Rate (%) Other Contamination Rate (%) QT3 Lab Specimen Acceptability Specimen Rejection Rate (%) Breakdown of rejection Reasons (%) QT7 Satisfaction with Outpatient Specimen Collection QT18 Specimen Acceptability in Blood Bank Patient Satisfaction Score Percent of Patients more than Satisfied Specimen Rejection Rate (%) Breakdown of rejection Reasons (%)

39 Solutions Error Prevention Multidisciplinary approach Phlebotomy / clinical / lab staff Communications / Feedback -Systematic and managed Offer Advice and ensure understanding Continuous quality improvement Root Cause analysis (RCA) Good practice/standardised practice (Guidelines)

40 Solutions - Standardisation & Best Practice PAI Phlebotomy Guidelines March 2010 CLSI (formerly NCCLS): Procedures for the Handling and Processing of Blood Specimens for Common Laboratory tests; Approved Guideline Fourth Edition. CLSI document H18-A4 (ISBN ). Clinical and Laboratory Standards Institute.

41 Solutions Training & Education Standardised Documented Training Needs Assessments annually Competency Training Re-Training Create training and competency culture

42 In Summary PAV s and hence PAEs occur through the lack of standardisation and so this is key. PAEs have significant effects on patient outcomes. Sample quality assurance = Improvement to the quality assurance of lab results. Systematic measurement, comparison with a standard, monitoring of processes and an associated feedback loop that confers error prevention. (

43 Thank you for your attention