Phlebotomy and the Biochemistry Dept

Felicity Dempsey

Senior Medical Scientist

Biochemistry Laboratory

St James’s Hospital

Role of Phlebotomist

• Inform patient of any test preparation

• Ensure correct sampling & handling

• Properly identify the patient

• Label sample with 2 unique identifiers

• Adherence Hospital Quality System

• Adherence Health & Safety Codes

• Minimise risk management

Role of Phlebotomist

• Knowledge of test requirements (user manual)• Universal Blood Precautions (CJD)• Ensure quality of sample• Ensure patient details stated correctly• Avoid haemolysis & microclotting• Prioritise STAT samples• Prompt dispatch• LIS/EPR operation

CPA STANDARDS

C3standard – The facilities for the patient should provide privacy during reception and sampling

C3.1 Waiting/Reception area with disabled access

Phlebotomy Area for privacy & recovery

Toilet facilities separate to staff

C3.2 Notices advising patients of Health & Safety precautions

E3 Specimen collection and handling

• E3.1 Lab management should establish procedures for specimen collection and handling

• E3.2 Procedures available to service users & those responsible for specimen collection and handling

• E3.3 Lab periodically reviews its sample volume requirements to ensure that neither insufficient nor excessive amounts are collected.

Sampling Procedures

• Venepuncture

• Finger prick

• Heel prick

• Capillary

Sample types

• Plasma (anticoagulated)

• Serum (clotted)

• Whole blood

Laboratory Process

• Preanalytical – Major Advances

Primary Sampling, Analysers

• Analytical – Instrumentation/Analyses

• Postanalytical – Final result

Preanalytical issues

• Diet

• Diurnal variations

• Drug Therapy

• Pregnancy

• Dehydration

• Patient’s current condition

Viruses

BacteriaFoods

Sunlight

Stress

Drugs

Genes

MenopausePregnancy

Post-pregnancy

Preanalytical

                                                                                                                                                 

Gender

Preanalytical issues

• Haemolysis

• Lipaemia

• Icterus

• Partially filled tubes

• Cross contamination

• Incorrect sample type

• Incorrect/inadequate labelling/unlabelled

Problems with vacuutainers

• Loss of vacuum

• Improper storage

• Incorrect sampling technique

• Incorrect blood/additive ratio

• Expired tubes

Blood containers

• Evacuated or syringe

• Gel separators

• Viscosity changes on centrifugation

• Inhibits cell metabolism

• Change of tube system validated by lab

Additives

• Liquid, spray dried or powder

• Anticoagulants

• Antiglycolytic

• Clot activators

• Trace element

Order of draw

• Blood Cultures

• Citrate

• Serum

• Heparin

• EDTA

• Oxalate

Essential precautions

• Invert gently to mix

• Vigorous mixing - haemolysis

• Cross contamination

• Never transfer between tubes

NCCLS H3-H5, Vol 23, No 23, 8.10.2

Anticoagulants

• Chelates/ precipitates calcium

• Ca unavailable coagulation process

• Inhibits thrombin formation

• Prevents Fibrinogen to Fibrin process

Commonly used in Biochemistry

• Colour coded tubes

• Lithium Heparin (green/orange)

• Fluoride Oxalate (grey)

• Clotted (red)

• Trace metal (royal blue)

• System to system variation

Test requisition

• Electronic Patient Register (EPR)

• Phlebotomy lists

• Bar coded labels

• Hospital Forms

• GP multidisciplinary forms

Minimum Acceptance Criteria

• Form / EPR label• Patients Name• MRN• Hospital /Ward• DOB• Referring Consultant• Date/Time collected (desirable)• Clinical Details (noted if not supplied)

Transport to Laboratory

• Pneumatic transport tube system

• Hospital porter

• Internal Couriers

• External Couriers

• Train

• Post

Considerations for Phlebotomists

• Transport on ice

• Transport frozen

• Light protected

• Requires immediate separation

• Refridgerated centrifuge

• Inform lab of impending arrival

Analytical issues

• Routine biochemistry (daily)

• Routine biochemistry (1-3 times weekly)

• STAT biochemistry

• Endocrinology

• POCT

• Discipline specific specialities

• Neonatal/Paediatric Biochemistry

Routine – Organ Profiling

• Renal /Liver/Bone/Cardiac profiles

• ICU profiles – ICU, HDU, BU, Oncology

• Overlap in some tests

• Glucose – random, fasting, post prandial

• Amylase

• Magnesium

Renal profile

• Urea

• Creatinine

• Sodium/Potassium (Na/K)

• Bicarbonate

Bone Profile

• Calcium (Ca)

• Inorganic Phosphate (In P)

• Alkaline Phosphate (ALP)

• Albumin

Liver profile

• Total Protein/Albumin

• Total Bilirubin

• Enzymes – GGT, ALP,

• Transaminases - AST, ALT

Cardiac Profiles/Markers

Enzymes• LDH, AST, CK

Markers

• CKMBM (mass measurement)

• Troponin T or I

• Pro BNP

Routine Biochemistry

• Lipid profiles• Therapeutic Drug Monitoring (TDM)- anti epileptic, anti asthmatic, lithium, digoxin• Diabetes monitoring- HbA1c, urinary microalbumen- Toxicology• Non blood biochemistry

Endocrinology

• Thyroid function tests

• Infertility testing

• Adrenal testing

• Growth & Development

• DM & Obesity

Specialities

• Porphyria

• Haemochromotosis typing

• Tumour Markers

• Bone Markers

• DNA analysis

• Metabolic disorders

• Neonatal screening

Irish Neonatal Metabolic Screening Programme

• Phenylketonuria (PKU)

• Maple Syrup Urine Disease (MSUD)

• Congenital Hypothyroidism (CHT)

• Galactosaemia

• Homocystinuria

Guthrie Cards

• Preanalytical Considerations• Adequate sample application• Air dry elevated / horizontal• No stacking - Cross Contamination• Other Contaminants: Powder / Lotions Alcohol wipes Urine, Faeces & Sweat

Commonly encountered sample problems

• Delay in separation (GP)• Haemolysis• Incorrect sample type• Cross contamination• Drip arm sample• Incorrect patient• Lipaemia• Icterus• Alcohol/Trace Metal Contamination

Timing of samples

• Fasting samples

• TDM requirements

• Digoxin - +6 hrs

• Stimulation tests

TDM requirements

• Efficacy Dose

• Avoid Toxicity

• Compliance

• Lithium – serum required

Chain of Custody Protocols

• Samples unsuitable medico-legal purposes

• Legal samples

• Coroner’s requests

• IndustryWork related injuryEmployee insurance schemesDrug screening

Glucose Testing

• Random

• Fasting

• 2hr PP

• GTT

• Incorrect Timing - misinterpretation

Take home message

• Reference ranges not consensus

• Method/ Instrument variation

• Possible sample type variation

• Protocols may differ

• Contact lab if unsure

Therapeutic Phlebotomy

• Haemochromatosis (Fe)

• Porphyria Cutanea Tarda (Fe)

• Polycytaemia (RBC)

Common aims

• Know & Comply Hospital/Dept Quality Policy• Reduce Turnaround Time (TAT)• Inform lab if urgent• Efficient transport• Efficient Reporting• Prioritise wards

(ICU/CCU/BU/AE/HDU/Oncology• POCT

Post analytical

• Data Review

• Delta checking

• Phone urgent results

• Additional testing

• Gender based reference ranges

Post analytical

• Electronic reports - Wards Healthlink, Medibridge

• Computer generated results

• OPD / Clinic lists

• Follow up letters/phonecalls

Changing face of Pathology

• Pathology review – just published

• 3 cold labs (GP work) ??S,W,E

• 14 hot labs (i.e. 14 A/E)

• Reduced from 48

• Country wide/combine hospitals

• Smaller hospitals – community hospitals

• Tenders – public/private interests

Changing face of Pathology

• Preanalytical analysers

• Blood Sciences

• Combined Biochemistry, Haematology, Immunology analysers

• Increased POCT

Why Don’t You……

• Visit your hospital laboratory

• Befriend the Lab Staff