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Lab Manual for Moffitt-Long and Mount Zion

Lab Manual for SFGH

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Reference Ranges & Critical Values

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  1. REFERENCE RANGES


Reference Ranges (“normal limits”) are usually determined by taking either the lowest and highest values (range) of results obtained on a normal population, the mean 2 standard deviations (S.D.) of the values obtained on a large population or the central 95% range. Thus at least 5% of healthy subjects will have values outside the reference range (“false positives”). The proportion of false positives may be even greater when the patient population is not closely matched to the control subjects with respect to age, sex, ethnic group, and other factors.


The reference range for each test is listed in the ALPHABETICAL LIST OF TESTS section. (Check Index). Reference ranges for common tests are in printed list form, available at the Administrative Office of the clinical lab. This list will be updated periodically. These reference ranges apply specifically to the SFGH Clinical Laboratory and the patients we serve.


  1. A NOTE ABOUT SI UNITS


The SI System (“Système International d’Unités”) is a “coherent” system of metric units developed around 1970. Its purpose is to standardize and simplify the units of measurement and eliminate the confusion surrounding the many variants of “metric” units that have developed since the meter was defined in 1800.


The World Health Organization recommended the SI system to the medical community in 1977, and most of the world has already adopted it. In the United States, acceptance has been much slower. For your convenience, both traditional units and SI units are listed in the following table. Further information about the SI system is available upon request from the Clinical Laboratory Director's office, NH 2M2, x 8588.


Reference Ranges for Common Laboratory Tests


CONSTITUENT

REFERENCE RANGES*

SI UNITS (if not already reported in SI Units)

Blood, Plasma, or Serum tests

Albumin

See specific test information



ALT

M:10-40

F: 7-35

U/L



Anion gap (No K)

7-16

mmol/L



AST

10-41

U/L



B-type natriuretic peptide (BNP)

<100

pg/mL

<7.0

pmol/L

β-hydroxybutyrate

0.02-0.27

mmol/L



Bilirubin, total

0.1-1.2

mg/dL

1.7-20.5

mcmol/L

Bilirubin, Direct

0.1-0.3

mg/dL

1.7-5.1

mcmol/L

Blood Gas,
Arterial

See specific test information



Calcium

8.6-10.5

mg/dL



Calcium, Ionized

1.12 – 1.32

mmol/L



Chloride

98-107

mmol/L



Cholesterol

<200

mg/dL

<5.17

mmol/L

CO2

22-29

mmol/L



Cortisol

See specific test information



Creatinine

0.6-1.3

mg/dL

53-115

mcmol/L

Ferritin

See specific test information



Glucose, Fasting

70-99

mg/dL

3.86-5.45

mmol/L

Glucose, Random

70-139

mg/dL

3.86-7.66

mmol/L

Hepatitis A

IgM Antibody

Negative




Hepatitis Bs Antigen

Negative




Hepatitis Bs Antibody

Negative




Hepatitis B Core Antibody

Negative




HCG

<5

U/L



Ionized Calcium

See Calcium, Ionized above



Iron

M: 65-175

F: 50-170

mcg/dL

11.64-31.34

8.96-30.45

mcmol/L

Iron% Saturation

16-60

%



LD

100-190

U/L



Lead

<10

mcg/dL

<0.48

mcmol/L

Lipase

7-58

U/L



Magnesium

1.7-2.4

mg/dL

0.70-0.99

mmol/L

Osmolality

275-295

mOsm/kg



Phosphatase, Alk.


M: 53-128

F: 42-98

U/L



Phosphorus

2.5-4.5

mg/dL

0.81-1.45

mmol/L

Potassium

3.5-5.1

mmol/L



Pregnancy test

Negative




Protein, total

6.4-8.3

g/dL

64-83

g/L

Sodium

136-145

mmol/L



Triglyceride

<150

mg/dL

<1.69

mmol/L

TSH-3rd Generation

0.37-4.42

mcIU/mL



Thyroxine, Free

0.65-1.80

ng/dL

8.4-23.2

pmol/L

Triiodothyronine, Free

2.30-4.20

pg/mL

3.54-6.47

pmol/L

Urea Nitrogen

6-20

mg/dL

2.1-7.1

mmol/L

Uric Acid

M: 3.5-8.5

F: 2.5-7.5

mg/dL


208-506

149-446

mcmol/L

Vitamin B12

236-888

pg/mL

174-655

pmol/L

Hematologic Values

Hemoglobin, Men

13.3-17.7

g/dL

133-177

g/L

Hemoglobin, Women

11.7-15.7

g/dL

117-157

g/L

Hematocrit, Men

39.8-52.2

%

0.40-0.52


Hematocrit, Women


34.9-46.9

%

0.35-0.47


Red Blood Cell Count:

Men

4.40-5.90 x 106/mcL

4.4-5.9 x 1012/L

Women

3.80-5.20 x 106/mcL

3.8-5.2 x 1012/L

MCV

80-100

fl

80-100

fl

Reticulocyte Count

0.5-2.0

%

0.005-0.02


Reticulocyte, Absolute

20-100

k/mcL



Sedimentation Rate (Westergren)

Children

0-10

mm/h



< Age 50, Men

0-15

mm/h



< Age 50, Women

0-20

mm/h



>Age 50, Men

0-20

mm/h



> Age 50, Women

0-30**

mm/h



Leukocytes

White Blood Cell Count (WBC)

3.9-11.7 x 103/mcL

3.9-11.7 x 1012/L

Platelets

Platelet Count

150-400 x 103/mcL

150-400 x 109/L

Coagulation Tests

Fibrinogen

170-440***

mg/dL



Fibrin D-Dimer

< 400

ng/mL

< 0.4

mg/L

Prothrombin Time (PT)

<14.5***

seconds



Partial Thrombin Time (APTT)


< 37.6***

seconds



Drug Levels - Therapeutic

Acetaminophen

10-30

mg/L

66-199

mcmol/L

Carbamazepine (Tegretol)

4.0-10.0

mg/L

17-42

mcmol/L

Digoxin

0.5-2.0

mcg/L

0.6-2.6

nmol/L

Gentamicin

peak 5.0-10.0

trough 1.0-2.0

mg/L

mg/L

10.5-20.9

2.1-4.2

mcmol/L

Lithium

0.5-1.5

mmol/L



Phenobarbital

15.0-40.0

mg/L

65-172

mcmol/L

Phenytoin (Dilantin)

10.0-20.0

mg/L

40-79

mcmol/L

Salicylate

< 25

mg/dL

< 1.81

mmol/L

Theophylline

10.0-20.0

mg/L

55.5-111

mcmol/L

Tobramycin

peak 5.0-10.0

trough 0.5-2.0

mg/L

mg/L

10.7-21.4

1.07-4.3

mcmol/L

Valproic Acid

50-100

mg/L

347-693

mcmol/L

Vancomycin

peak 20-40

trough 5-15

mg/L


10-24

3.5-10.4

mcmol/L


Urine Tests

Calcium

50-300

mg/24 hr

12.5-74.9

mmol/24 hr

Chloride

140-250

mmol/24 hr



Creatinine

0.8-2.0

g/24 hr

7.1-17.7

mmol/24 hr

Creatinine Clearance

90-130

mL/min/ 1.73m2

0.87- 1.25

mL/s/m2

Glucose

< 0.5

g/24 hr

< 2.8

Mmol/24 hr

Osmolality

50-1200

mOsm/kg



Phosphorus

0.4-1.3

g/24 hr

12.9-42.0

mmol/24 hr

Potassium

25-125

mmol/24 hr



Protein, total

< 0.16

g/24 hr



Sodium

40-220

mmol/24 hr



Urea Nitrogen

12-20

g/24 hr

4.3-7.1

mmol/24 hr

Uric Acid

0.25-0.75

g/24 hr

1.49-4.46

mmol/24 hr

Spinal Fluid (CSF)

Glucose

60-80

% blood level


Protein, total

15-45

mg/dL

150-450

mg/L


* Adult values unless otherwise specified.

** > Age 65, may exceed 40 mm/h.

*** May vary depending on reagent lot number.

† Typical maintenance levels. Actual values differ in each individual.

‡ Therapeutic ranges not established for random sampling




  1. CRITICAL VALUES


When the laboratory becomes aware of a critical value, i.e., an extreme and possibly life-threatening value, we will call the requesting physician or patient care unit immediately. It is essential that the correct clinic/ward location is provided on the requisition to facilitate notification of critical values. (Note: There may be some delay between submission of a routine specimen and telephone notification, as the abnormal result may be identified only after the entire analytical run has been completed and reviewed.) The following values have been adopted in communication with the medical staff of SFGHTC and are reviewed annually by the Hospital's Medical Executive Committee.


Constituent

Conventional Units

SI Units

Acetaminophen

> 50

mg/L

> 331

mcmol/L

Blood Gases, Arterial

pH

< 7.20 or > 7.55


PCO2

< 25 or > 65

mm Hg


PO2

< 40

mm Hg


0 to 30 days

< 40 or > 100

mm Hg


Blood Gases, Arterial and Capillary, Infant

pH

< 7.20 or > 7.55


PCO2

< 25 or > 65

mm Hg


Base Deficit, 0 to 30 days, only

> 10

mmol/L


Blood Gases, Venous and Arterial, Cord Blood

pH

< 7.0


Base Deficit

> 10

mmol/L


Calcium

< 6.5 or > 13.5

mg/dL

< 1.62 or > 3.37

mmol/L

Calcium, ionized

< 0.8 or > 1.55

mmol/L


Carbamazepine

> 15

mg/L

> 63.5

mcmol/L

CO2, Total

< 15 or > 40

mmol/L


Cooximetry, Venous and Arterial

Carboxyhemoglobin

> 14.9

%


Methemoglobin

> 14.9

%


Digoxin

> 2.0

mcg/L

> 2.6

nmol/L

Ethanol *

> 400

mg/dL

> 87

nmol/L

Fibrinogen

< 75

mg/dL


Gentamicin

> 12.0

mg/L

25.1

mcmol/L

Glucose, CSF

< 30 or > 300

mg/dL

< 1.65 or > 16.53

mmol/L

Glucose

< 50 or > 500

mg/dL

< 2.76 or > 27.55

mmol/L

Glucose for neonates

< 30 or > 170

mg/dL

< 1.65 or > 16.53

mmol/L

Hemoglobin

< 7 or > 20

g/dL

< 70

g/L

INR

> 4.9

Lactate

> 3.9

mmol/L


Lithium

> 2.0

mmol/L


Magnesium

< 1.0 or > 4.5

mg/dL

< 0.41 or > 1.85

mmol/L

Osmolality

< 240 or > 320

mOsm/kg


Phenobarbital

> 50

mg/L

> 216

mcmol/L

Phenytoin (Dilantin)

> 35

mg/L

> 139

mcmol/L

Phosphorus

< 1

mg/dL

< 0.32

mmol/L

Platelets

< 25 or > 1000

103/ mcL

< 25 or > 1000

x109/L

Potassium

< 3.0 or > 6.0

mmol/L


PT

(See INR)


PTT

> 68.9

sec


Salicylate

> 35

mg/dL

>2.53

mmol/L

Sodium

< 125 or > 155

mmol/L


Theophylline

> 30

mg/L

> 167

mcmol/L

Tobramycin

> 12

mg/L

> 47.6

mcmol/L

Valproic Acid

> 150

mg/L

> 1040

mcmol/L

Vancomycin

> 80

mg/L

> 55

mcmol/L

WBC**

< 1.5 or > 100

103/mcL

< 1.5 or > 100

x109/L


* As requested by Emergency Department, critical ethanols are not called.

** For each patient, only the first critical WBC every 30 days will be reported by telephone.


Unusual or potentially life-threatening microbiological findings will also be reported immediately by telephone, including positive cultures from blood, CSF, or other normally sterile body fluids.


Blood Bank will call immediately whenever there are delays expected in release or unavailability of blood components, or in case a transfusion reaction work-up suggests a serious adverse effect such as hemolysis, sepsis or transfusion-related acute lung injury (TRALI).


“Read-back” of all critical results (including both stat and critical values) reported verbally or by telephone is requested to verify values and assure accuracy, in accordance with Joint Commission’s National Patient Safety Goals.


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