Patient: 55 y female (ambulatory)

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2 Disclosures Speaking Honoraria Radiometer (Canada) Nova Biomedical, Draeger Roche Diagnostics (Canada) Research Support (Reagents, Instrumentation, Travel) Nova Biomedical Abbott Laboratories (Canada) Roche Diagnostics (Canada) Radiometer (Canada) Instrumentation Laboratories (Canada) ALOL Biomedical Inc. Clinical laboratory consulting company 2

3 Patient: 55 y female (ambulatory) Sodium Potassium Chloride Lab Result (plasma) 133 mmol/l 4.65 mmol/l 94.9 mmol/l Blood Gas Analyzer

4 Patient: 55 y female (ambulatory) Lab Result (plasma) Blood Gas Analyzer Sodium 133 mmol/l 157 mmol/l Potassium 4.65 mmol/l 5.4 mmol/l Chloride 94.9 mmol/l 117 mmol/l

5 Patient: 55 y female (ambulatory) Lab Result (plasma) Blood Gas Analyzer Sodium 133 mmol/l 157 mmol/l Potassium 4.65 mmol/l 5.4 mmol/l Chloride 94.9 mmol/l 117 mmol/l Huge Difference!

6 Patient: 78 y male (cancer clinic) Sodium Potassium Chloride Lab Result 136 mmol/l 4.14 mmol/l 96.6 mmol/l Blood Gas Analyzer

7 Patient: 78 y male (cancer clinic) Plasma Lab Result Blood Gas Analyzer Sodium 136 mmol/l 157 mmol/l Potassium 4.14 mmol/l 4.8 mmol/l Chloride 96.6 mmol/l 118 mmol/l

8 Patient: 78 y male (cancer clinic) Plasma Lab Result Blood Gas Analyzer Sodium 136 mmol/l 157 mmol/l Potassium 4.14 mmol/l 4.8 mmol/l Chloride 96.6 mmol/l 118 mmol/l Enormous Difference!

9 WTF (What s that from?)

10 How can a hospital verify performance of electrolyte methods for hospitalized (critically ill) patients?

11 How can a hospital verify performance of electrolyte methods for hospitalized (critically ill) patients? Are there any tools that we can use?

12 Answer: No

13 Answer: No We need to establish verification materials & a verification system or tool to address the UNIQUE challenges provided with hospitalized & critically ill patient populations

14 Answer: No We need to establish verification materials & a verification system or tool to address the UNIQUE challenges provided with hospitalized & critically ill patient populations What are the specific challenges?

15 Blood is a complex mixture of cells, water and dissolved materials Plasma Blood Cells

16 Blood is a complex mixture of cells, water and dissolved materials Plasma Healthy: 93% Water 7% Protein & Lipids Blood Cells Healthy: 43% Hematocrit

17 Blood is a complex mixture of cells, water and dissolved materials Plasma Ill Patients: 93% Water Blood Cells Ill Patients : 43% Hematocrit

18 In the clinical laboratory, we currently assume the cells, water and dissolved materials DO NOT VARY and have NO BIAS OR INFLUENCE ON TEST RESULTS

19 In the clinical laboratory, we currently assume the cells, water and dissolved materials DO NOT VARY and have NO BIAS OR INFLUENCE ON TEST RESULTS

20 TxA-cQ_AUIDigB&biw=1336&bih=841

21 Aren t all electrolyte methods generally the same?

22 Chemistry Analyzer Blood Gas Analyzer

23 Chemistry Analyzer Whole blood (plasma) Specimen Type Blood Gas Analyzer Whole blood (whole blood)

24 Chemistry Analyzer Whole blood (plasma) Specimen Type Blood Gas Analyzer Whole blood (whole blood) Indirect Electrodes Electrolyte Method Direct Electrodes

25 Chemistry Analyzer Whole blood (plasma) Specimen Type Blood Gas Analyzer Whole blood (whole blood) Indirect Electrodes Electrolyte Method Direct Electrodes 90 minutes from collection Turn around time 30 minutes from collection

26 Chemistry Analyzer Whole blood (plasma) Specimen Type Blood Gas Analyzer Whole blood (whole blood) Indirect Electrodes Electrolyte Method Direct Electrodes 90 minutes from collection Turn around time 30 minutes from collection Hemolysis, lipemia, inadequate specimen collection Interferences Hemolysis, inadequate specimen collection

27 Chemistry Analyzer Whole blood (plasma) Specimen Type Blood Gas Analyzer Whole blood (whole blood) Indirect Electrodes Electrolyte Method Direct Electrodes 90 minutes from collection Turn around time 30 minutes from collection Hemolysis, lipemia, inadequate specimen collection Interferences Hemolysis, inadequate specimen collection

28 What effect will lipemia have on the measurement of electrolytes?

29 Why are we concerned about lipemia interference?

30 Why are we concerned about lipemia interference? Interfere with many laboratory tests

31 Why are we concerned about lipemia interference? Interfere with many laboratory tests Capillary electrophoresis abnormal α 2

32 Why are we concerned about lipemia interference? Interfere with many laboratory tests Capillary electrophoresis abnormal α 2 Immunoassays interfere with antigen/antibody

33 Why are we concerned about lipemia interference? Interfere with measured analytes Capillary electrophoresis abnormal α 2 Immunoassays interfere with antigen/antibody Spectrophotometric assays Lipoprotein particles absorb light AST, ALT, glucose

34 Why are we concerned about lipemia interference? Interfere with measured analytes Capillary electrophoresis abnormal α 2 Immunoassays interfere with antigen/antibody Spectrophotometric assays Lipoprotein particles absorb light AST, ALT, glucose Indirect Electrodes (Na, K, Cl)

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36 Indirect Electrode 7% protein + lipid 93% Plasma Water 10uL (9.3 ul)

37 Indirect Electrode -Dilution Effect 7% protein + lipid 93% Plasma Water 10uL (9.3 ul) ul Diluent 9.3ul/199.3uL = 21.4 fold dilution

38 Indirect Electrode -Dilution Effect 7% protein + lipid 10% protein + lipid 93% Plasma Water 10uL (9.3 ul) 90% Plasma Water 10uL (9.0 ul) ul Diluent 9.3ul/199.3uL = 21.4 fold dilution

39 Indirect Electrode -Dilution Effect 7% protein + lipid 10% protein + lipid 93% Plasma Water 10uL (9.3 ul) 90% Plasma Water 10uL (9.0 ul) ul Diluent ul Diluent 9.3ul/199.3uL = 21.4 fold dilution 9.0ul/199.0uL = 22.1 fold dilution (3.2% decrease relative to 93% plasma water due to the dilution effect)

40 - Principle of Potentiometry is used for both electrodes

41 - Principle of Potentiometry is used for both electrodes - InDirect electrodes - DILUTION - Should be affected by plasma changes

42 - Principle of Potentiometry is used for both electrodes - InDirect electrodes - DILUTION - Should be affected by plasma changes - Direct electrodes - NO DILUTION - Should be unaffected by plasma changes - (Blood Gas Analyzers)

43 What is the distribution of plasma water content amongst different patient populations?

44 Waugh Equation (1969) Plasma Water Content = 99.1 (total protein *.73) (triglycerides *1.03) =.93 normal total protein reference intervals (adults) ( g/dl) normal triglycerides reference intervals (adults) ( mg/dl)

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46 Frequency 50 Community Testing Children Plasma Water Content % % 80.00% % 40.00% Frequency Cumulative % % % Bin

47 Frequency 18 Hospitalized Children Plasma Water Content Frequency Cumulative % Bin

48 Plasma Water Concentration Gestational Age (weeks)

49 How could plasma water changes theoretically influence electrolyte measurement?

50 7% protein + lipid 93% water Indirect mmol/l Direct 140 mmol/l Normal plasma

51 7% protein + lipid 93% water Indirect mmol/l 10% protein + lipid 90% water Indirect mmol/l Direct 140 mmol/l Direct 140 mmol/l Normal plasma Hyperlipid Hyperprotein plasma

52 7% protein + lipid 93% water Indirect mmol/l 10% protein + lipid 90% water Indirect mmol/l 1% 99% water Indirect mmol/l Direct 140 mmol/l Direct 140 mmol/l Direct 140 mmol/l Normal plasma Hyperlipid Hyperprotein plasma ICU patient plasma

53 What do we do in the lab to assess the potential effect of lipid (plasma water) on the measurement of electrolytes?

54 Intralipid is used as a lipoprotein substitute to test interference Emulsion used for IV administration as a source of calories and essential fatty acids Intralipid particles range from nm (mean 345 nm) Are smaller than large chylomicrons but bigger than medium and large VLDLs Effect is NOT identical with pathologically induced lipemia

55 ISE Indirect Na,K, Cl (Manufacturer Package Insert) Lipemia: Intralipid does not interfere in the tested concentration range up to 2000 mg/dl (corresponding to approximate L index of 2000). There is poor correlation between the L index (corresponds to turbidity) and the triglycerides concentration. Pseudohyponatremia may be seen with lipemic specimens as a result of fluid displacement Chemistry Lab Analyzer

56 Blood Gas Analyzer (Direct Electrode) Lipemia should have NO effect

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58 Patient: 55 y female (ambulatory) Lab Result (plasma) Blood Gas Analyzer Sodium 133 mmol/l 157 mmol/l Potassium 4.65 mmol/l 5.4 mmol/l Chloride 94.9 mmol/l 117 mmol/l Huge Difference!

59 Patient: 78 y male (cancer clinic) Plasma Lab Result Blood Gas Analyzer Sodium 136 mmol/l 157 mmol/l Potassium 4.14 mmol/l 4.8 mmol/l Chloride 96.6 mmol/l 118 mmol/l Enormous Difference!

60 Patient: 55 y female (ambulatory) Plasma Indirect Electrode Direct Electrode Sodium 133 mmol/l 157 mmol/l Potassium 4.65 mmol/l 5.4 mmol/l Chloride 94.9 mmol/l 117 mmol/l Triglyceride 3.21 mmol/l H Index 15 I Index 0 L Index 162

61 Patient: 78 y male (cancer clinic) Plasma Indirect Electrode Direct Electrode Sodium 136 mmol/l 157 mmol/l Potassium 4.14 mmol/l 4.8 mmol/l Chloride 96.6 mmol/l 118 mmol/l Triglyceride 2.79 mmol/l H Index 0 I Index 0 L Index 202

62 What happens to the electrolyte results (lab result) after we try to remove the lipemia?

63 Patient: 55 y female (ambulatory) Plasma Lab Blood Gas Lab (after air fuge) Sodium 133 mmol/l 157 mmol/l 155 mmol/l Potassium 4.65 mmol/l 5.4 mmol/l 5.38 mmol/l Chloride 94.9 mmol/l 117 mmol/l mmol/l Triglyceride 3.21 mmol/l 2.52 mmol/l H Index 15 Indicator of hemolysis 36 I Index 0 Indicator of icterus 1 L Index 162 Indicator of lipemia 16

64 Patient: 78 y male (cancer clinic) Plasma Lab Blood Gas Lab (after air fuge) Sodium 136 mmol/l 157 mmol/l 155 mmol/l Potassium 4.14 mmol/l 4.8 mmol/l 4.74 mmol/l Chloride 96.6 mmol/l 118 mmol/l 112 mmol/l Triglyceride 2.79 mmol/l 1.92 mmol/l H Index 0 Indicator of hemolysis 13 I Index 0 Indicator of icterus 0 L Index 202 Indicator of lipemia 30

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67 Sodium: 16 mmol/l Chloride: 52 mmol/l Potassium: 100 mmol/l Sodium: 140 mmol/l Chloride: 104 mmol/l Potassium: 4.4 mmol/l LDH: 58,000 U/L AST: 500 U/L ALT: 150 U/L LDH: 360 U/L AST: 25 U/L ALT: 30 U/L Am J. Clin. Path. 37: 445, 1962

68 release of K + from as few as 0.5% of erythocytes can increase K + values by 0.5 mmol/l Tietz Textbook of Clinical Chemistry, 3 rd Edition Hemolysis

69 How do we currently detect hemolysis? Hemolysis Index (Automated Clinical Chemistry Systems) Spectrophotometric assessment Blanked bichromatic measurements 405 nm and 700nm

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72 Edward R. Burns, Noriko Yoshikawa Department of Pathology, Albert Einstein College of Medicine and Montefiore Medical Center, New York, NY.

73 Frequency Distribution of H Index (NICU, Well Baby Nursery) N= H Index

74 Frequency 500 Distribution of H Index (NICU, Well Baby Nursery) % of all specimens are visually hemolyzed N= H Index

75 What are Hemolysis Rates at RUH? 4.7% (overall hemolysis rate-venipuncture)

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78 Clinical Laboratory Parameters Hematocrit? Plasma Water Concentration? Protein Concentration Triglyceride Concentration Patient Characteristics Ambulatory? Intensive Care? Burn Patient? Renal Disease? Medications/Treatments TPN? Chemotherapeutic Agents? The Patient

79 EDITORIAL COMMENT NOT

80 Overall conclusions Errors in electrolyte measurement related to patient plasma water (and hematocrit) are currently NOT detected by QC or external proficiency testing programs These factors are a component of the technical limitation to achieving concordance of results between plasmacentral lab indirect and whole blood-direct methods.

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82 Thank you for your time and attention!