Sample handling: Sample handling Malcolm Dunlop Directorate Quality Manager


Clinical Sciences Building 1: Clinical Sciences Building 1


Slide3: Clinical Sciences Building 2


Laboratory Departments: Laboratory Departments Typical DGH Clinical Biochemistry (Chemical Pathology) Haematology Histopathology Microbiology


Laboratory Departments: Laboratory Departments Teaching hospital / tertiary referral Clinical Biochemistry (Chemical Pathology) Haematology Histopathology Microbiology Immunology Virology Sub Fertility – associate department Cytology Others e.g. Genetics


What constitutes a sample: What constitutes a sample Any biological material taken from a patient for diagnostic, prognostic or therapeutic monitoring Under the new Human Tissues Act tissue includes blood urine & other fluids faeces sweat semen tissue


Infection risks: Infection risks All samples must be considered to be infectious Use of “Universal Precautions” handling Never assume any sample is “safe” Today’s symptoms may be tomorrow’s diagnosis of infection


Phases of analysis: Phases of analysis Pre-analytical (from the patient to the lab) Analytical Post-analytical (from the lab to the notes)


From the patient to the lab: From the patient to the lab What can (and does) go wrong Incorrect identification of patient Patient preparation – fasting, diet, supine, time, drugs. Sample poorly/ incorrectly taken Inaccurate timing Wrong type of sample


From the patient to the lab: From the patient to the lab What can (does) go wrong? Incorrect container(s) Under-filling Mislabelling/ no labelling Incorrect storage/ transport (ice, warm, delay) Loss, breakage etc.


The Patient: The Patient Do patients always disclose history? Confused Frightened In pain Want to help !!! Are previous diagnoses available?


Quality: Quality Laboratories can only produce quality results on quality samples And on quality requests Rubbish In Rubbish Out Ideal sample mimics the in vivo state


Requesting: Requesting Requested on PAS = electronic return Requested manually = NO electronic return Electronic/ manual mixed requesting = break in electronic record


Results: Results Telephoned results are the most unsafe method Electronic are safest and quickest Hardcopy reports must be filed as per instructions


Blood collection: Blood collection Ask patients to identify themselves When blood taken write all relevant details on collection tubes immediately


Sample acceptance: Sample acceptance Patient safety is of the utmost importance Samples and requests MUST allow clear identification the patient Samples identified incorrectly will NOT be processed


Sample acceptance: Sample acceptance The sample MUST include patient’s:- Surname Forename Date of Birth or Hospital Number or NHS number Histology specimens MUST include Hospital number


Other information: Other information SHOULD include Ward Date of collection Time of collection e.g. Cortisol


Sample acceptance: Sample acceptance Request form MUST contain patient’s:- Surname Forename Date of Birth and/ or Hospital or NHS number Ward or clinic Tests requested


Samples for Blood Transfusion: Samples for Blood Transfusion MANDATORY identification requirements As previous plus signature and printed name of requestor on form Signature of person collecting the blood on the sample tube(s) and on request form Date of request and of sample See Blood Transfusion Policy


Slide21: Venous blood sampling Syringe Hybrid Evacuated


Blood collection: Blood collection Use the blood collection system in use Advantages over needle & syringe Higher quality sample Minimises clotting mechanism Produces correct blood to anticoagulant ratio when properly filled Easier Quicker


Sampling problems - blood: Sampling problems - blood Inappropriate site – drip arm, mastectomy, burns etc Timing Incorrect use of tourniquet Wrong container Incorrect order of draw Transportation


Urine collection: Urine collection 24 hour sample must include all urine passed in this period If less than 24h, inform the lab Mid stream sample – self explanatory Early morning sample – often best Correct container type


Urine samples: Urine samples Incorrect timing Inappropriate for test required Sterility Volume


Other considerations: Other considerations Swabs for culture may need specific transport media e.g. Chlamydia Blood cultures – special bottles & technique for taking the blood Tissue for Histology – fixative * Extreme care needed when using formalin