EVOLVING ASPECTS OF QUALITY

ASSURANCE IN LABORATORY

TESTING

Patrick St.Louis, PhD, Dip Clin Chem

Sainte-Justine Hospital

Montreal, Canada

Congress SCPC, 2004

Quality the total characteristics of a process or procedure that affect its ability to satisfy its intended application

To appreciate the need for quality we must understand the impact of poor quality

automobile: safety/accidents, repairs - time and cost

cigar: taste, low satisfaction, poor reputation - sales

laboratory test result: inappropriate treatment

delays in treatment

direct harm - repeat punctures

social and economic harm

Quality Assurance (QA) the systematic activities needed to ensure that the requirements of quality will be met.

An efective laboratory QA program will provide reliable test results with a minimum of delay and the efficient use of resources, taking care to address patient safety and to minimise laboratory errors.

Select processes and identify steps for improvement

Need objectives with measurable quality indicators; objectives should have clinical, patient care relevance.

For example: “To reduce the number of unlabelled specimens received”

measurable

patient care relevance: number of repeat sticks

time delay to results and treatment

The laboratory QA program must consider all phases of the laboratory testing process and the steps that can benefit from quality improvement

pre-analytical, analytical and post-analytical

Pre-analytical phase

patient identification specimen:collection, identification

laboratory: reception and verification pre-test handling: separation

decanting

aliquotting (labelling)

Patient identification: (CRITICAL)Armbands

“No specimen shall be drawn from a patient who is not wearing an armband”

Double identification: name (ask), numberSpecial situations: newborns, patients in the ER

Sample identification: care should be taken to correctly identify the specimen at this time.

Specimen collection: proper procedure; repeat

punctures; correct samples - no omissions; needlestick injuries

identification: label must be affixed transport: delays (time-stamping, tube systems) inappropriate and un-protected samples Sample volume issues

Pre-analytical phase patient identification specimen:collection, identification

laboratory: reception and verification data/order entry pre-test handling: separation

decanting

aliquotting (labelling) delay or loss in laboratory (this occurs more

often than we would like)

Studies on laboratory errors pre-analytical errors 30%-75% of total errors patient/specimen ID errors 34 - 58% of pre-

analalytical errorsBonini et al. Clin Chem 2002; 48:691-698

Astion et al. Am J Clin Pathol 2003; 120:18-26

CAP-Q Probes study

Order entry errors can be as high as 5% of tests entered; most frequent test request not entered

Valenstein & Meier, Arch Pathol Lab Med 1999; 123:1145-1150

Analytical phase

need well-written protocols (methods; format)

ensure reliability of test (NCCLS, ISO):

establish or verify linearity

verify limits of detection and analytical range

evaluate precision and accuracy

establish institution-specific reference ranges

reagent handling: storage, expiry dates; fridge temperatures

instrument breakdown and repair logs: down time causes loss of effective working time and delays in results

Quality control (QC) operational techniques and activities that are used to fulfill requirements for quality

QC for the analytical phase :

traditional

automatic

electronic

Continuous system monitoring: total system; remote sensing and monitoring

use of split samples and other means of internal assessment and monitoring

concordance between analysers

External QC programs (proficiency testing)

External QC results and proficiency testing material as tests of trueness

Post-analytical phase Result validation: automatic, absurd results

(contamination by IV fluids, saline, glucose,)

Reflex testing eg TSH and T3, T4 Reports and interpretations (HbS, tumor markers) Managing critical and unusual results:

protocols defining critical values and actions calls and read backs

Problems inherent in manual entry of results Sample storage and retrieval for supplementary

testing; a good system saves time

The total QA process can benefit from the laboratory information system (LIS):

time stamps

identity tags

traceability from specimen collection to test result

previous results and delta checks

format of laboratory reports; reference values and comments

Approach to QA program

Develop protocols and policies Identify intervention points Use Risk Reports: laboratory and/or

hospital; government mandated reporting Prepare regular QA reports; ensure

distribution and follow up.

Preparation of QA reports and follow up

statistical analysis: by period, by clinical unit

explain/understand the consequences of particular problems and the reason for actions: eg improper sample identification leading to sample rejection or certification; real or potential harm to the patient

avoid blame and seek support interdisciplinary problems

Some policies at HSJ

patient identification

specimen identification and certification

specimens delayed in transport (use of pneumatic tube system)

adequate filling of specimen tubes (anti-coagulation)

instrument maintenance, breakdown and repair log sheets

temperature logs for refrigerators and freezers

critical values protocols: values and actions

Specimen ID errors: HSJ protocol rejection Specimen not identified/labelled no requisition identification errors: wrong patient, wrong

label on specimen, wrong requisition, sample and requisition do not match

Are all mis-labelled samples rejected?

Some samples are hard to replace Certification by someone responsible on the

clinical side

HSJ 2003/2004: from “Certification Forms” 132 sample-related incidents

64 - no identification

36 - wrong identification

number of rejections = 90

number of certifications and acceptances = 8

We have noted a marked decrease in the number of events; under-reporting of problem cases ?

What about when the test is already done and the report sent; removing results from the patient chart; do not transfer results

Responsibility for QA:

Everyone

An institutional issue, having administrative support

Uses analytical and statistical tools

Two aspects

identify and resolve any current problems

long range anticipation to improve processes

Publications: NCCLS documents

ISO 15189: Standards for Medical Laboratories Relating to Quality and Competence