Point of care testing

1. Point of care testing Lecture 6

2. Definition • Medical testing at or near the site of patient care. • It is a mode of analysis which is performed at the site where the health care is provided close to the patient. • Bed side, near patient, physician’s office, extra laboratory, off site, unit used testing.

3. Advantages • Reduced turnaround time (TAT). • Improved health outcomes. • Rapid data availability. • Self contained and user friendly instruments. • Small sample volume for large test menu. • Ability to test many types of samples.

4. Disadvantages • Bedside tests performed by poorly trained non-laboratorian. • Cost of POCT compared with traditional laboratory testing. • Quality of testing is operator dependent. • Narrower measuring range for some of the analytes.

5. Characteristics of POCT devices • First result in minutes or less. • Portable instruments with consumable reagent cartridges. • A one or two step operating protocol. • The capability of performing direct specimen analysis on whole blood and urine. • Simple procedure that do not require laboratory trained operator.

6. Characteristics of POCT devices • Built in/ integrated calibration and quality control. • Results provided as hard copy, stored and available for transmission. • Low instrument cost. • Built in regulatory record keeping. • Temperature storage for reagents.

7. Point of care testing might be employed Primary care • Home • Community pharmacist • Health centers (general practice) • Workplace clinic • Physician’s office • Paramedical support vehicle (ambulance, helicopter, air craft )

8. Secondary and tertiary care • Emergency room • Admission unit • Operating room • Intensive care unit • Wards • Outpatient clinics

9. Types of devices used for POCT • Single use qualitative or semi-quantitative cartridge strip test • Single use quantitative cartridge/ strip test with a reader device • Multiple use quantitative cartridge/bench top devices

10. Single use qualitative or semi-quantitative cartridge strip test • Urine chemistry • Blood chemistry • Infectious disease agents • Cardiac markers • hCG

11. Single use quantitative cartridge/ strip test with a reader device • Glucose • Blood chemistry • Coagulation • Cardiac markers • Drugs • CRP • Allergy • Fertility testing • pH • HbA1c • Blood gases • Electrolytes

12. Multiple use quantitative cartridge/bench top devices • pH • Blood gases • Electrolytes • Metabolites • Complete blood count • Bilirubin • Cardiac marker • CRP

13. POCT devices available in the hospitals • Blood gases, electrolytes, lactate • Cardiac biomarkers, renal markers, Bilirubin • Cholesterol, triglyceride and HDL • Intra-operative PTH measurement • Blood glucose (includes self-testing devices) • Alcohol and toxicology (paracetamol, drugs of abuse) • Urinalysis(with or without a reader)

14. POCT devices available in the hospitals • Haemoglobin A1c • Albumin • Anticoagulant therapy monitoring (includes self-testing devices) • Detection of pregnancy and ovulation (includes self-testing devices) • Infections(Chlamydia, HIV) • Stool occult blood

15. POCT devices available in community setting • Blood glucose (includes self-testing devices) • Urinalysis(with or without a reader) • Cholesterol, triglyceride and HDL • Anticoagulant therapy monitoring (includes self-testing devices) • Detection of pregnancy and ovulation (includes self-testing devices)

16. Cardiac markers • The American Heart Association has recommended a turnaround time for cardiac markers of 60 minutes. • Tests of POCT should be compatible to the results of the central laboratory. • Improved diagnosis • Shortened emergency department length of stay • Decreasing patient time in the emergency department by 45 minutes.

17. Glucose monitoring programme • First glucometer was introduced by “Bayer” in 1969. • Old standard is the laboratory based test. • Glucometer give the rapid and relatively precise glucose estimation on whole blood at the patients bedside. • Frequent blood glucose monitoring allows better glycemic control in hospital as well as at home. • Reduced morbidity and mortality associated with glycemic control.

18. limitations • POCT glucose is slightly higher than venous blood. • This difference is significant in case of postprandial specimen. • Other interferences include hematocrit, po2, temperature and humidity. • Use of POCT not recommended in shock, dibetic coma and dehydartion.