Nursing and allied health · Study chart

Lab values study chart

Seven common lab panels with 38 typical adult reference ranges, what each value measures, the BUN to creatinine ratio explained with practice numbers, the abbreviations, and 20 practice questions. Free, and for study only: it cannot be used for a real patient or your own labs.

7 panels, one chart
BUN:creatinine ratio explained
20 practice questions
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Part 1 · The chart

Common lab panels and their typical adult ranges

Typical adult reference ranges from the cited textbooks; every lab publishes its own. For study only: this chart cannot be used for a real patient or for your own labs.

38 values across seven panels: a lab values cheat sheet in one place. Pick a panel, or type an abbreviation or a name to find one value. Where two of the cited textbooks disagree, the row shows one range and names the other, because that is what you will meet on the floor.

Find a value

Complete blood count (CBC)

Counts the cells in whole blood: red cells, white cells and platelets, plus the hemoglobin, the hematocrit and the red-cell indices. A CBC with differential also splits the white cells into their five types.

Common tube: Lavender (EDTA) in most labs, mixed by gentle inversion. Order of draw

Value	Typical adult range	What it measures
WBCWhite blood cell count	4,500 to 11,000 per µL (4.5 to 11.0 × 10⁹/L)	The total number of white cells, the cells that fight infection and clear debris.OpenStax Anatomy and Physiology 2e teaches 5,000 to 10,000 per µL: two trusted sources, two ranges.
RBCRed blood cell count	Male 4.2 to 5.7 million per µL · Female 3.8 to 5.1 million per µL	The number of red cells, the cells that carry oxygen on their hemoglobin.The OpenStax nursing appendix lists 4.7 to 6.2 million/mm³ for men and 4.5 to 5.0 for women.
HgbHemoglobin	Male 13.8 to 17.2 g/dL · Female 12.1 to 15.1 g/dL	The iron-rich protein inside red cells that carries oxygen.Also written Hb. The OpenStax Clinical Nursing Skills appendix lists 13 to 17 g/dL (men) and 12 to 16 g/dL (women).
HctHematocrit	Male 42% to 52% · Female 37% to 47%	The share of the blood volume that is red cells (also called packed cell volume).Open RN teaches that it rises when fluid volume is low (the blood is more concentrated) and falls when fluid volume is high. MedlinePlus lists a lower set (men 37% to 48%, women 34% to 43%).
PLTPlatelet count	150,000 to 400,000 per µL (150 to 400 × 10⁹/L)	The cell fragments that start a clot and plug a damaged vessel.
MCVMean corpuscular volume	79 to 95 fL	The average size of a red cell.
MCHMean corpuscular hemoglobin	Female 26 to 33 pg per cell · Male 27 to 33 pg per cell	The average amount of hemoglobin in each red cell.
MCHCMean corpuscular hemoglobin concentration	32 to 36 g/dL	How much hemoglobin a red cell holds for its size.

WBCWhite blood cell count
Typical adult range
4,500 to 11,000 per µL (4.5 to 11.0 × 10⁹/L)
What it measures
The total number of white cells, the cells that fight infection and clear debris.
Note
OpenStax Anatomy and Physiology 2e teaches 5,000 to 10,000 per µL: two trusted sources, two ranges.
RBCRed blood cell count
Typical adult range
Male 4.2 to 5.7 million per µL · Female 3.8 to 5.1 million per µL
What it measures
The number of red cells, the cells that carry oxygen on their hemoglobin.
Note
The OpenStax nursing appendix lists 4.7 to 6.2 million/mm³ for men and 4.5 to 5.0 for women.
HgbHemoglobin
Typical adult range
Male 13.8 to 17.2 g/dL · Female 12.1 to 15.1 g/dL
What it measures
The iron-rich protein inside red cells that carries oxygen.
Note
Also written Hb. The OpenStax Clinical Nursing Skills appendix lists 13 to 17 g/dL (men) and 12 to 16 g/dL (women).
HctHematocrit
Typical adult range
Male 42% to 52% · Female 37% to 47%
What it measures
The share of the blood volume that is red cells (also called packed cell volume).
Note
Open RN teaches that it rises when fluid volume is low (the blood is more concentrated) and falls when fluid volume is high. MedlinePlus lists a lower set (men 37% to 48%, women 34% to 43%).
PLTPlatelet count
Typical adult range
150,000 to 400,000 per µL (150 to 400 × 10⁹/L)
What it measures
The cell fragments that start a clot and plug a damaged vessel.
MCVMean corpuscular volume
Typical adult range
79 to 95 fL
What it measures
The average size of a red cell.
MCHMean corpuscular hemoglobin
Typical adult range
Female 26 to 33 pg per cell · Male 27 to 33 pg per cell
What it measures
The average amount of hemoglobin in each red cell.
MCHCMean corpuscular hemoglobin concentration
Typical adult range
32 to 36 g/dL
What it measures
How much hemoglobin a red cell holds for its size.

Basic metabolic panel (BMP)

Eight values from the liquid part of the blood: blood sugar, the four main electrolytes, calcium, and the two kidney waste products. It is the smaller of the two metabolic panels.

Common tube: A serum tube (red or gold) or a heparin plasma tube (green), as the lab directs; glucose goes in the gray tube when processing will be delayed. Order of draw

Value	Typical adult range	What it measures
GluGlucose	70 to 100 mg/dL, fasting	Blood sugar, the body’s main fuel.A non-fasting (random) value depends on when the person last ate.
CaCalcium	8.5 to 10.2 mg/dL	The mineral behind nerve signals, muscle contraction, heart rhythm, clotting and bone.Open RN teaches 8.6 to 10.2 mg/dL.
NaSodium	135 to 145 mEq/L	The main electrolyte outside the cells; it sets fluid balance between the blood and the tissues.Open RN teaches 136 to 145 mEq/L.
KPotassium	3.7 to 5.2 mEq/L	The main electrolyte inside the cells; heart, nerve and muscle function depend on it.Open RN teaches 3.5 to 5.1 mEq/L, and the OpenStax nursing appendices list 3.5 to 5.2 and 3.5 to 5.1. Your lab’s range is the one on the report.
CO₂Carbon dioxide (bicarbonate)	23 to 29 mEq/L	Mostly bicarbonate, the form in which the blood carries carbon dioxide; part of acid-base balance.
ClChloride	96 to 106 mEq/L	An electrolyte that travels with sodium; fluid balance and acid-base balance.
BUNBlood urea nitrogen	6 to 20 mg/dL	The nitrogen carried as urea, the waste left when protein is broken down; the kidneys remove it.Open RN teaches 7 to 20 mg/dL and notes that it rises when fluid volume is low, because the blood is more concentrated.
CrCreatinine	0.6 to 1.3 mg/dL	A waste product of muscle work, filtered out by the kidneys; the value the eGFR estimate is built on.By sex, MedlinePlus gives 0.7 to 1.3 mg/dL for men and 0.5 to 0.95 mg/dL for women. It depends on muscle mass.

GluGlucose
Typical adult range
70 to 100 mg/dL, fasting
What it measures
Blood sugar, the body’s main fuel.
Note
A non-fasting (random) value depends on when the person last ate.
CaCalcium
Typical adult range
8.5 to 10.2 mg/dL
What it measures
The mineral behind nerve signals, muscle contraction, heart rhythm, clotting and bone.
Note
Open RN teaches 8.6 to 10.2 mg/dL.
NaSodium
Typical adult range
135 to 145 mEq/L
What it measures
The main electrolyte outside the cells; it sets fluid balance between the blood and the tissues.
Note
Open RN teaches 136 to 145 mEq/L.
KPotassium
Typical adult range
3.7 to 5.2 mEq/L
What it measures
The main electrolyte inside the cells; heart, nerve and muscle function depend on it.
Note
Open RN teaches 3.5 to 5.1 mEq/L, and the OpenStax nursing appendices list 3.5 to 5.2 and 3.5 to 5.1. Your lab’s range is the one on the report.
CO₂Carbon dioxide (bicarbonate)
Typical adult range
23 to 29 mEq/L
What it measures
Mostly bicarbonate, the form in which the blood carries carbon dioxide; part of acid-base balance.
ClChloride
Typical adult range
96 to 106 mEq/L
What it measures
An electrolyte that travels with sodium; fluid balance and acid-base balance.
BUNBlood urea nitrogen
Typical adult range
6 to 20 mg/dL
What it measures
The nitrogen carried as urea, the waste left when protein is broken down; the kidneys remove it.
Note
Open RN teaches 7 to 20 mg/dL and notes that it rises when fluid volume is low, because the blood is more concentrated.
CrCreatinine
Typical adult range
0.6 to 1.3 mg/dL
What it measures
A waste product of muscle work, filtered out by the kidneys; the value the eGFR estimate is built on.
Note
By sex, MedlinePlus gives 0.7 to 1.3 mg/dL for men and 0.5 to 0.95 mg/dL for women. It depends on muscle mass.

Comprehensive metabolic panel (CMP): the BMP plus six

Fourteen values: everything in the BMP plus two proteins, three liver enzymes and bilirubin. BMP vs CMP comes down to those six liver-side values; the eight shared values and their ranges are on the BMP tab.

Common tube: The same tube as the BMP: serum (red or gold) or heparin plasma (green), as the lab directs. Order of draw

Value	Typical adult range	What it measures
AlbAlbumin	3.4 to 5.4 g/dL	The main blood protein, made by the liver; it carries small substances and keeps fluid from leaking out of the vessels.
TPTotal protein	6.0 to 8.3 g/dL	Albumin and the globulins together.
ALPAlkaline phosphatase	20 to 130 U/L	An enzyme found in all tissues, with more in the liver, the bile ducts and bone.Normally higher in growing children and in pregnancy. MedlinePlus’s own ALP page lists 40 to 129 IU/L.
ALTAlanine aminotransferase	4 to 36 U/L	An enzyme found at high levels in the liver; the more liver-specific of the two transaminases.
ASTAspartate aminotransferase	8 to 33 U/L	An enzyme found at high levels in the liver, the heart and muscle.
T biliTotal bilirubin	0.1 to 1.2 mg/dL	The yellow pigment left when red cells are broken down; the liver processes it into bile.Direct (conjugated) bilirubin: less than 0.3 mg/dL.

AlbAlbumin
Typical adult range
3.4 to 5.4 g/dL
What it measures
The main blood protein, made by the liver; it carries small substances and keeps fluid from leaking out of the vessels.
TPTotal protein
Typical adult range
6.0 to 8.3 g/dL
What it measures
Albumin and the globulins together.
ALPAlkaline phosphatase
Typical adult range
20 to 130 U/L
What it measures
An enzyme found in all tissues, with more in the liver, the bile ducts and bone.
Note
Normally higher in growing children and in pregnancy. MedlinePlus’s own ALP page lists 40 to 129 IU/L.
ALTAlanine aminotransferase
Typical adult range
4 to 36 U/L
What it measures
An enzyme found at high levels in the liver; the more liver-specific of the two transaminases.
ASTAspartate aminotransferase
Typical adult range
8 to 33 U/L
What it measures
An enzyme found at high levels in the liver, the heart and muscle.
T biliTotal bilirubin
Typical adult range
0.1 to 1.2 mg/dL
What it measures
The yellow pigment left when red cells are broken down; the liver processes it into bile.
Note
Direct (conjugated) bilirubin: less than 0.3 mg/dL.

Electrolytes beyond the BMP

Sodium, potassium, chloride, bicarbonate and calcium are on the BMP tab. An electrolyte panel can add magnesium and phosphate, and fluid-balance questions often add serum osmolality. The anion gap, calculated from the electrolytes, is a separate value some labs report.

Common tube: Serum (red or gold) or heparin plasma (green), as the lab directs. Order of draw

Value	Typical adult range	What it measures
MgMagnesium	1.7 to 2.2 mg/dL	Needed for normal muscle and nerve function, for the heart, for strong bones and for many of the body’s chemical processes.Open RN teaches 1.5 to 2.4 mEq/L. That is a different unit, so the two ranges are not interchangeable: always read the unit on the report.
PhosPhosphorus (phosphate)	2.8 to 4.5 mg/dL (adults)	A mineral the body uses to build bone and teeth; also part of nerve signaling and muscle contraction.Open RN teaches 2.5 to 4.0 mg/dL. Children run higher.
OsmSerum osmolality	275 to 295 mmol/kg	How concentrated the blood is: the number of dissolved particles per kilogram of water.Open RN pairs it with hematocrit and BUN as the labs that rise when fluid volume is low and fall when it is high. The OpenStax nursing appendix lists 285 to 295 mOsm/kg.

MgMagnesium
Typical adult range
1.7 to 2.2 mg/dL
What it measures
Needed for normal muscle and nerve function, for the heart, for strong bones and for many of the body’s chemical processes.
Note
Open RN teaches 1.5 to 2.4 mEq/L. That is a different unit, so the two ranges are not interchangeable: always read the unit on the report.
PhosPhosphorus (phosphate)
Typical adult range
2.8 to 4.5 mg/dL (adults)
What it measures
A mineral the body uses to build bone and teeth; also part of nerve signaling and muscle contraction.
Note
Open RN teaches 2.5 to 4.0 mg/dL. Children run higher.
OsmSerum osmolality
Typical adult range
275 to 295 mmol/kg
What it measures
How concentrated the blood is: the number of dissolved particles per kilogram of water.
Note
Open RN pairs it with hematocrit and BUN as the labs that rise when fluid volume is low and fall when it is high. The OpenStax nursing appendix lists 285 to 295 mOsm/kg.

Coagulation studies

How long plasma takes to clot, measured two ways that check two different sets of clotting factors, plus the INR that makes PT comparable between labs. The platelet count on the CBC tab is the other half of the clotting picture.

Common tube: Light blue (sodium citrate), filled to the line: the tube is built for a 9:1 blood-to-additive ratio. Order of draw

Value	Typical adult range	What it measures
PTProthrombin time	11 to 13.5 seconds (not on blood thinners)	How many seconds plasma takes to clot through one set of clotting factors (the extrinsic and common pathways).The OpenStax nursing appendix lists 11 to 13 seconds.
INRInternational normalized ratio	0.8 to 1.1 (not on blood thinners)	The PT converted to a standard number so results compare across labs and reagents.MedlinePlus: a person on an oral anticoagulant is usually dosed to an INR of 2.0 to 3.0. The OpenStax nursing appendix lists 0.8 to 1.2.
aPTTActivated partial thromboplastin time	25 to 35 seconds	How many seconds plasma takes to clot through the other set of factors (the intrinsic pathway); used to monitor heparin.Also written PTT.

PTProthrombin time
Typical adult range
11 to 13.5 seconds (not on blood thinners)
What it measures
How many seconds plasma takes to clot through one set of clotting factors (the extrinsic and common pathways).
Note
The OpenStax nursing appendix lists 11 to 13 seconds.
INRInternational normalized ratio
Typical adult range
0.8 to 1.1 (not on blood thinners)
What it measures
The PT converted to a standard number so results compare across labs and reagents.
Note
MedlinePlus: a person on an oral anticoagulant is usually dosed to an INR of 2.0 to 3.0. The OpenStax nursing appendix lists 0.8 to 1.2.
aPTTActivated partial thromboplastin time
Typical adult range
25 to 35 seconds
What it measures
How many seconds plasma takes to clot through the other set of factors (the intrinsic pathway); used to monitor heparin.
Note
Also written PTT.

Arterial blood gas (ABG)

Five values from arterial blood: how acidic it is, the pressures of the two gases, the bicarbonate, and the oxygen saturation. Together they describe gas exchange and acid-base balance.

Common tube: Not a routine tube: an arterial sample, usually from the wrist, drawn by a trained clinician and sent to the lab right away. Order of draw

Value	Typical adult range	What it measures
pHArterial pH	7.35 to 7.45	How acidic or basic the arterial blood is.MedlinePlus lists a tighter 7.38 to 7.42. Nursing texts teach the wider range.
PaCO₂Partial pressure of carbon dioxide	35 to 45 mm Hg	The pressure of carbon dioxide dissolved in arterial blood: the respiratory side of acid-base balance.MedlinePlus lists 38 to 42 mm Hg.
HCO₃⁻Bicarbonate	22 to 26 mEq/L	The buffer the kidneys manage: the metabolic side of acid-base balance.MedlinePlus lists 22 to 28 mmol/L.
PaO₂Partial pressure of oxygen	75 to 100 mm Hg (at sea level)	The pressure of oxygen dissolved in arterial blood.The OpenStax nursing appendices list 80 to 100.
SaO₂Oxygen saturation	94% to 100%	The share of hemoglobin that is carrying oxygen.

pHArterial pH
Typical adult range
7.35 to 7.45
What it measures
How acidic or basic the arterial blood is.
Note
MedlinePlus lists a tighter 7.38 to 7.42. Nursing texts teach the wider range.
PaCO₂Partial pressure of carbon dioxide
Typical adult range
35 to 45 mm Hg
What it measures
The pressure of carbon dioxide dissolved in arterial blood: the respiratory side of acid-base balance.
Note
MedlinePlus lists 38 to 42 mm Hg.
HCO₃⁻Bicarbonate
Typical adult range
22 to 26 mEq/L
What it measures
The buffer the kidneys manage: the metabolic side of acid-base balance.
Note
MedlinePlus lists 22 to 28 mmol/L.
PaO₂Partial pressure of oxygen
Typical adult range
75 to 100 mm Hg (at sea level)
What it measures
The pressure of oxygen dissolved in arterial blood.
Note
The OpenStax nursing appendices list 80 to 100.
SaO₂Oxygen saturation
Typical adult range
94% to 100%
What it measures
The share of hemoglobin that is carrying oxygen.

Lipid panel

Total cholesterol, the LDL and HDL fractions that carry it, and triglycerides, the fat the body stores from extra calories.

Common tube: A serum tube (red or gold) in many labs, often after a fast. Order of draw

These are desirable levels for adults 20 and older, not a reference range: a lipid report is read against targets, and the targets differ by age.

Value	Typical adult range	What it measures
TCTotal cholesterol	Less than 200 mg/dL	All the cholesterol in the blood, across every carrier.
LDLLDL cholesterol	Less than 100 mg/dL	Low-density lipoprotein, the carrier textbooks call the “bad” cholesterol.
HDLHDL cholesterol	60 mg/dL or higher is best	High-density lipoprotein, the “good” carrier that moves cholesterol away from the vessels.Less than 40 mg/dL for men and less than 50 mg/dL for women counts as low.
Non-HDLNon-HDL cholesterol	Less than 130 mg/dL	Total cholesterol minus HDL: every carrier except the good one.
TGTriglycerides	Less than 150 mg/dL	The fat the body makes from extra calories and stores in fat cells.150 to 199 is borderline high, 200 to 499 high, 500 or above very high.

TCTotal cholesterol
Typical adult range
Less than 200 mg/dL
What it measures
All the cholesterol in the blood, across every carrier.
LDLLDL cholesterol
Typical adult range
Less than 100 mg/dL
What it measures
Low-density lipoprotein, the carrier textbooks call the “bad” cholesterol.
HDLHDL cholesterol
Typical adult range
60 mg/dL or higher is best
What it measures
High-density lipoprotein, the “good” carrier that moves cholesterol away from the vessels.
Note
Less than 40 mg/dL for men and less than 50 mg/dL for women counts as low.
Non-HDLNon-HDL cholesterol
Typical adult range
Less than 130 mg/dL
What it measures
Total cholesterol minus HDL: every carrier except the good one.
TGTriglycerides
Typical adult range
Less than 150 mg/dL
What it measures
The fat the body makes from extra calories and stores in fat cells.
Note
150 to 199 is borderline high, 200 to 499 high, 500 or above very high.

Sources are listed at the end of the page: MedlinePlus, the OpenStax nursing appendices, OpenStax Anatomy and Physiology 2e and Open RN Nursing Fundamentals 2e. Check anything important against your program’s materials and the reference range printed on the report.

Part 2 · The ratio

The BUN:creatinine ratio, as a study concept

Two kidney wastes, one division. Programs teach the ratio because it shows how the nephron handles urea and creatinine differently, and because it turns up on chemistry reports. Here is the idea in five steps, then the arithmetic on practice numbers.

For study only. This section cannot be used for a real patient or for your own labs: a clinician reads a ratio together with each value, the trend and the whole person, never alone.

What it is
Divide the BUN by the creatinine, both in mg/dL, and write the answer as a ratio to 1. A BUN of 15 mg/dL with a creatinine of 1.0 mg/dL is 15:1. Some lab reports print it next to the BUN and creatinine.
Why the two wastes behave differently
Both are filtered at the glomerulus. Urea is then partly pulled back: OpenStax puts it at about half in the proximal tubule, with more reabsorbed in the collecting duct when antidiuretic hormone is high. Creatinine is not reabsorbed at all (0 g a day in the OpenStax table); a little is even secreted into the urine.
The prerenal pattern: a ratio above 20
When blood flow to the kidney drops but the tubules still work, the proximal tubule reabsorbs urea avidly (and antidiuretic hormone adds more), so BUN climbs faster than creatinine and the ratio rises. Textbooks call that the prerenal pattern. The Merck Manual calls a ratio above 15 abnormal, and its acute kidney injury table uses above 20 for the prerenal pattern.
The tubular pattern and the low ratio
When the kidney tubules themselves are injured, urea is reabsorbed less, so both values rise together and the ratio stays ordinary or falls; the Merck table uses below 10 for tubular injury. A low ratio is also taught with low protein intake and with liver disease, which makes less urea.
Why it is only a clue
BUN moves with protein intake, gastrointestinal bleeding, trauma, infection, corticosteroids and the breakdown of body protein, and creatinine depends on muscle mass. Merck calls the ratio suggestive but generally inconclusive on its own, and the 20 cut-off is a textbook convention that a 2012 review calls arbitrary. Labs outside the US often report urea and creatinine in SI units; a ratio built from those sits on a different scale and cannot be compared with the mg/dL one.

Work the arithmetic

Four practice pairs, none of them a person. Tap one to see the division and the pattern textbooks give it.

Part 3 · Abbreviations

The abbreviations and units on a lab sheet

49 short forms you will read on orders and reports, with the units at the end. Charting and prescription shorthand (bid, prn, NPO) lives on the medical abbreviations page.

CBC: Complete blood countRed cells, white cells, platelets, hemoglobin, hematocrit, indices.
Diff: DifferentialThe white cell count split into its five types.
WBC: White blood cell count
RBC: Red blood cell count
Hgb / Hb: Hemoglobin
Hct: HematocritThe share of blood that is red cells.
PLT: Platelet count
MCV: Mean corpuscular volumeAverage red cell size.
MCH: Mean corpuscular hemoglobinAverage hemoglobin per red cell.
MCHC: Mean corpuscular hemoglobin concentration
BMP: Basic metabolic panelEight values: glucose, calcium, Na, K, CO₂, Cl, BUN, creatinine.
CMP: Comprehensive metabolic panelThe BMP plus albumin, total protein, ALP, ALT, AST and bilirubin.
BUN: Blood urea nitrogen
Cr / Creat: Creatinine
eGFR: Estimated glomerular filtration rateAn estimate of how fast the kidneys filter, calculated from the creatinine together with age and sex (some formulas add body size).
Na: Sodium
K: Potassium
Cl: Chloride
CO₂ / HCO₃⁻: Carbon dioxide / bicarbonateOn a chemistry panel the CO₂ value is mostly bicarbonate.
Ca: Calcium
Mg: Magnesium
Phos / PO₄: Phosphorus / phosphate
Glu: Glucose
Alb: Albumin
TP: Total protein
ALP: Alkaline phosphatase
ALT: Alanine aminotransferaseOlder name: SGPT.
AST: Aspartate aminotransferaseOlder name: SGOT.
T bili: Total bilirubin
PT: Prothrombin time
INR: International normalized ratioThe PT standardized across labs.
aPTT / PTT: Activated partial thromboplastin time
ABG: Arterial blood gas
PaO₂: Partial pressure of oxygen, arterial
PaCO₂: Partial pressure of carbon dioxide, arterial
SaO₂: Arterial oxygen saturation
TC: Total cholesterol
LDL: Low-density lipoprotein cholesterol
HDL: High-density lipoprotein cholesterol
TG: Triglycerides
µL / mcL: MicroliterOne millionth of a liter; cell counts are per microliter. Also written mm³.
g/dL: Grams per deciliterHemoglobin and the proteins.
mg/dL: Milligrams per deciliterGlucose, BUN, creatinine, calcium, magnesium, lipids.
mEq/L: Milliequivalents per literThe electrolytes. For sodium, potassium and chloride it equals mmol/L.
mmol/L: Millimoles per literThe SI unit many labs outside the US use for most chemistry values.
fL: FemtoliterThe MCV unit: a red cell’s volume.
pg: PicogramThe MCH unit.
U/L: Units per literEnzyme activity: ALP, ALT, AST. Also written IU/L.
mm Hg: Millimeters of mercuryGas pressures on an ABG.

Part 4 · Practice questions

20 practice questions

Ranges, what each value measures, the tubes, the ABG and the ratio arithmetic, multiple choice, one at a time. Every answer is explained, and your score is free: no sign-up needed.

Question 1 of 20

MedlinePlus gives the typical white blood cell count as

The bonus

The printable pocket chart and 30 more questions

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A pocket chart to print: every value on this page with its typical adult range, panel by panel, in two columns on one sheet, with the study-only line on it.
30 more practice questions: the red-cell indices, the liver values, the extra electrolytes, the ABG, and four more ratio patterns. Every answer explained.

Unlock it in the box above

Sources

Where these facts come from

Every range, meaning and ratio cut-off on this page is written in our own words from these public sources. Where they differ on a number, the chart names both; on a report, the lab’s own range decides.

OpenStax, Clinical Nursing Skills, Appendix A: Adult Lab Values · A nursing textbook’s one-page table: CBC, metabolic panel, ABG, coagulation and lipids, with the note that values change by facility.
OpenStax, Fundamentals of Nursing, Appendix A: Adult Lab Values · The same table in a second OpenStax nursing text; the ABG ranges nursing students are taught.
OpenStax, Anatomy and Physiology 2e, 18.1 An Overview of Blood · Hematocrit ranges by sex and what the hematocrit is.
OpenStax, Anatomy and Physiology 2e, 18.4 Leukocytes and Platelets · The white cell count and what leukocytes and platelets do.
OpenStax, Anatomy and Physiology 2e, 25.6 Tubular Reabsorption · How much urea and creatinine the nephron filters, reabsorbs and excretes: the physiology behind the BUN:creatinine ratio.
Open RN, Nursing Fundamentals 2e, 15.4 Electrolytes · The electrolyte ranges a nursing fundamentals course teaches, and what each electrolyte does.
Open RN, Nursing Fundamentals 2e, 15.6 Applying the Nursing Process · Hematocrit, BUN and serum osmolarity as fluid-balance labs, with their ranges.
MedlinePlus, Complete Blood Count (CBC) · What each CBC value measures.
MedlinePlus Medical Encyclopedia, WBC count · The white cell range.
MedlinePlus Medical Encyclopedia, RBC count · The red cell ranges by sex.
MedlinePlus Medical Encyclopedia, Hemoglobin · The hemoglobin ranges by sex.
MedlinePlus Medical Encyclopedia, Hematocrit · A second, lower set of hematocrit ranges, quoted in the chart’s note.
MedlinePlus Medical Encyclopedia, Platelet count · The platelet range.
MedlinePlus Medical Encyclopedia, RBC indices · MCV, MCH and MCHC.
MedlinePlus, Basic Metabolic Panel (BMP) · The eight BMP values and what each measures.
MedlinePlus, Comprehensive Metabolic Panel (CMP) · The fourteen CMP values and how the CMP differs from the BMP.
MedlinePlus Medical Encyclopedia, Comprehensive metabolic panel · Every BMP and CMP range on the chart, from one page so they agree with each other.
MedlinePlus, BUN (Blood Urea Nitrogen) · What urea nitrogen is; liver disease as a cause of a low BUN.
MedlinePlus, Creatinine Test and Creatinine blood test · What creatinine is, the eGFR, and the ranges by sex (encyclopedia article 003475).
MedlinePlus, Electrolyte Panel · What each electrolyte does, and the anion gap.
MedlinePlus Medical Encyclopedia, Magnesium blood test · The magnesium range.
MedlinePlus Medical Encyclopedia, Phosphorus blood test · The phosphorus range for adults and for children.
MedlinePlus Medical Encyclopedia, ALP blood test · Where alkaline phosphatase comes from, and its own range.
MedlinePlus Medical Encyclopedia, Bilirubin blood test · Direct and total bilirubin.
MedlinePlus Medical Encyclopedia, Prothrombin time (PT) · PT and INR ranges, and the usual INR target on an oral anticoagulant.
MedlinePlus, Prothrombin Time Test and INR (PT/INR) · Why the INR exists.
MedlinePlus Medical Encyclopedia, Partial thromboplastin time (PTT) · The aPTT range.
MedlinePlus, Partial Thromboplastin Time (PTT) Test · Which clotting factors the aPTT checks, and heparin monitoring.
MedlinePlus Medical Encyclopedia, Blood gases · PaO₂ and oxygen saturation, and a narrower set of pH, PaCO₂ and bicarbonate values.
MedlinePlus, Arterial Blood Gas (ABG) Test · What each ABG component is and how the arterial sample is drawn.
MedlinePlus, Cholesterol Levels · The desirable lipid levels for adults 20 and older.
MedlinePlus Medical Encyclopedia, Triglyceride level · The triglyceride categories.
Merck Manual Professional Edition, Evaluation of the Patient With Renal Issues · What the BUN:creatinine ratio is used for, the above-15 cut-off, what else moves the BUN, and why the ratio is only suggestive.
Merck Manual Professional Edition, Acute Kidney Injury (AKI) · The diagnostic-indices table: ratio above 20 for the prerenal pattern, below 10 for tubular injury.
Uchino, Bellomo and Goldsmith, The meaning of the blood urea nitrogen/creatinine ratio in acute kidney injury (Clinical Kidney Journal, 2012) · The traditional 20 threshold and its arbitrary origin; what else raises BUN; antidiuretic hormone and urea reabsorption.
Manoeuvrier et al., Diagnostic performance of serum blood urea nitrogen to creatinine ratio (BMC Nephrology, 2017) · Avid urea reabsorption by the proximal tubule when the kidney is under-perfused but the tubules work; the mmol/L version of the ratio.

Questions

Common questions

Yes. The chart, the ratio section, the abbreviations and the 20 practice questions with your score are free, and none of it needs a sign-up. An email unlocks the bonus: a printable pocket chart and 30 more questions.

A basic metabolic panel has eight values: glucose, calcium, sodium, potassium, carbon dioxide, chloride, BUN and creatinine. A comprehensive metabolic panel has those eight plus six liver-side values: albumin, total protein, alkaline phosphatase, ALT, AST and total bilirubin, fourteen in all. The BMP and CMP tabs on the chart show each set with its range.

The BUN divided by the creatinine, both in mg/dL, written as a ratio to 1. Programs teach it because urea is partly reabsorbed by the kidney tubules while creatinine is not, so when blood flow to a working kidney drops, BUN climbs faster than creatinine and the ratio rises. The Merck Manual calls a ratio above 15 abnormal and uses above 20 for the prerenal pattern and below 10 for tubular injury, while also calling the ratio suggestive but generally inconclusive on its own. Part 2 walks through it with practice numbers.

Because every lab publishes its own reference range for its own method and population, and textbooks differ too: MedlinePlus gives the white cell count as 4,500 to 11,000 per µL, OpenStax Anatomy and Physiology as 5,000 to 10,000. The chart shows typical adult ranges from the cited sources and names the other source where they disagree. On a report, the range printed next to the value is the one that counts.

No. This is a study aid for people in nursing, medical assisting and other allied-health programs. It cannot be used for a real patient or for your own labs: nothing on this page is typed in or interpreted, and a clinician reads a value together with the trend, the other values and the whole person. Questions about a result go to the clinician who ordered it.

Each panel on the chart names its common tube: lavender EDTA for the CBC, light blue citrate filled to the line for the coagulation studies, a serum or heparin plasma tube for the chemistry panels, and an arterial sample for the blood gas. The order-of-draw page covers the tubes, their additives and the order they are drawn in. Your lab’s manual decides on the bench.

Lab values study chart

Common lab panels and their typical adult ranges

Complete blood count (CBC)

Basic metabolic panel (BMP)

Comprehensive metabolic panel (CMP): the BMP plus six

Electrolytes beyond the BMP

Coagulation studies

Arterial blood gas (ABG)

Lipid panel

The BUN:creatinine ratio, as a study concept

What it is

Why the two wastes behave differently

The prerenal pattern: a ratio above 20

The tubular pattern and the low ratio

Why it is only a clue

Work the arithmetic

The abbreviations and units on a lab sheet

20 practice questions

MedlinePlus gives the typical white blood cell count as

Get the printable pocket chart and 30 more questions

The printable pocket chart and 30 more questions

Where these facts come from

Common questions

Is the chart free?

What is the difference between a BMP and a CMP?

What is the BUN to creatinine ratio?

Why do the ranges here differ from my textbook, or from a lab report?

Can I use this to read my own lab results, or a patient’s?

Which tube does each panel go in?