# Normal Lab Values for Nurses: CBC, Electrolytes, BMP, CMP & ABG Charts

- Link: https://mynursinghub.com/normal-lab-values-nursing/
- Published: 2026-10-29T16:05:49+05:00
- Author: admin

**Normal lab values for nurses** are reference intervals used to recognize common
blood and urine findings. This nursing lab values chart covers complete blood count(
CBC), electrolytes, basic and comprehensive metabolic panels (BMP/CMP), kidney and
liver function, glucose and HbA1c, coagulation tests, arterial blood gases (ABGs),
and urinalysis. It pairs each example range with a practical nursing assessment 
point.

**Start here:** The numbers below are **examples for adult study**, not universal“
safe” thresholds. Reference intervals differ between laboratories, methods, ages
and clinical situations. Check the range printed on the patient’s report, assess
the patient and follow your local escalation policy. A “normal” result cannot rule
out illness, and an out-of-range result is not itself a diagnosis.

Jump to lab values and study questions

 1.  [What are normal lab values in nursing?](https://mynursinghub.com/normal-lab-values-nursing/#what-are-normal-lab-values-in-nursing)
 2.  [Quick reference: common nursing lab values chart](https://mynursinghub.com/normal-lab-values-nursing/#quick-reference-common-nursing-lab-values-chart)
 3.  [Complete blood count (CBC/FBC) normal lab values](https://mynursinghub.com/normal-lab-values-nursing/#complete-blood-count-cbcfbc-normal-lab-values)
 4.  [Electrolyte lab values: sodium, potassium, chloride, bicarbonate, calcium and magnesium](https://mynursinghub.com/normal-lab-values-nursing/#electrolyte-lab-values-sodium-potassium-chloride-bicarbonate-calcium-and-magnesium)
 5.  [Basic metabolic panel (BMP) versus comprehensive metabolic panel (CMP)](https://mynursinghub.com/normal-lab-values-nursing/#basic-metabolic-panel-bmp-versus-comprehensive-metabolic-panel-cmp)
 6.  [Kidney function lab values: BUN, creatinine, eGFR and urine findings](https://mynursinghub.com/normal-lab-values-nursing/#kidney-function-lab-values-bun-creatinine-egfr-and-urine-findings)
 7.  [Liver function tests (LFTs): ALT, AST, ALP, bilirubin and albumin](https://mynursinghub.com/normal-lab-values-nursing/#liver-function-tests-lfts-alt-ast-alp-bilirubin-and-albumin)
 8.  [Glucose and HbA1c: reference values versus diagnostic cutoffs](https://mynursinghub.com/normal-lab-values-nursing/#glucose-and-hba1c-reference-values-versus-diagnostic-cutoffs)
 9.  [Coagulation lab values: PT, INR and aPTT](https://mynursinghub.com/normal-lab-values-nursing/#coagulation-lab-values-pt-inr-and-aptt)
 10. [Arterial blood gas (ABG) normal values for nursing students](https://mynursinghub.com/normal-lab-values-nursing/#arterial-blood-gas-abg-normal-values-for-nursing-students)
 11. [Urinalysis normal values and bedside nursing significance](https://mynursinghub.com/normal-lab-values-nursing/#urinalysis-normal-values-and-bedside-nursing-significance)
 12. [Critical lab values: what nurses must recognize and report](https://mynursinghub.com/normal-lab-values-nursing/#critical-lab-values-what-nurses-must-recognize-and-report)
 13. [How to study lab values without confusing units or reference ranges](https://mynursinghub.com/normal-lab-values-nursing/#how-to-study-lab-values-without-confusing-units-or-reference-ranges)
 14. [Worked nursing examples: connecting patterns to assessment](https://mynursinghub.com/normal-lab-values-nursing/#worked-nursing-examples-connecting-patterns-to-assessment)
 15. [Practice questions with answers for nursing students](https://mynursinghub.com/normal-lab-values-nursing/#practice-questions-with-answers-for-nursing-students)
 16. [Frequently asked questions about normal lab values for nurses](https://mynursinghub.com/normal-lab-values-nursing/#frequently-asked-questions-about-normal-lab-values-for-nurses)
 17. [Related nursing study guides](https://mynursinghub.com/normal-lab-values-nursing/#related-nursing-study-guides)

**Related nursing study guide:** For the physiology behind renal tests and fluid
balance, review [kidney function and electrolyte regulation](https://mynursinghub.com/anatomy-physiology-nursing/#urinary).

## What are normal lab values in nursing?

A **reference interval** is a span of test results expected in a defined reference
population using a particular method. It is not the same as a treatment target, 
a diagnostic cutoff, or a “critical value.” A laboratory report typically shows 
the test, the result, its units, the laboratory’s reference interval, and sometimes
an H or L flag.

In nursing practice, values are useful for recognizing patterns that need assessment.
A low hemoglobin may accompany bleeding or anemia; a rising creatinine may suggest
deteriorating kidney function; and abnormal potassium can matter when evaluating
cardiac symptoms. None of those markers should be interpreted without observations,
history, medication exposure, timing, and the clinical plan.

 * **Reference interval:** a laboratory-specific comparison range.
 * **Clinical decision limit:** a cutoff used for a particular diagnosis or management
   decision, such as HbA1c criteria.
 * **Critical result:** a result the laboratory flags for prompt communication according
   to its approved policy.
 * **Trend:** changes across results, particularly when measured by the same laboratory
   and assay.

The distinction matters. Some hospital reference intervals are narrower or wider
than the examples in textbooks. [MedlinePlus explains how laboratory reference ranges vary](https://medlineplus.gov/lab-tests/how-to-understand-your-lab-results/).
If your question is _how to interpret_ a report rather than _what values to memorize_,
use our [step-by-step laboratory interpretation guide](https://mynursinghub.com/interpreting-lab-results-nursing/).

## Quick reference: common nursing lab values chart

Use this compact study chart as a **quick-revision reference** before studying the
individual panels. The numeric examples reflect commonly published adult intervals;
their units are as important as the numbers.

  |  Common test |  Example adult interval |  Nursing study point |  
   |  White blood cells (WBC) |  4.5–11.0 ×10^(9)/L |  Compare with temperature, symptoms, immunosuppression and recent treatment. |  
 |  Hemoglobin (Hb), adults |  Approximately 13.8–17.2 g/dL (men); 12.1–15.1 g/dL (women) |  Review symptoms, bleeding history and trend; ranges vary by population. |  
 |  Platelets |  150–400 ×10^(9)/L |  Assess bleeding, bruising, clotting context and platelet trend. |  
 |  Sodium (Na^(+)) |  135–145 mmol/L |  Assess fluid balance, neurological changes and correction plan. |  
 |  Potassium (K^(+)) |  3.7–5.2 mmol/L in one published panel |  Check symptoms, ECG when indicated, kidney function, medications and hemolysis flags. |  
 |  Creatinine |  0.6–1.3 mg/dL in one published panel |  Review urine output, previous results, hydration and muscle mass. |  
 |  BUN |  6–20 mg/dL |  Interpret alongside creatinine, fluids, protein intake and illness. |  
 |  Magnesium |  1.7–2.2 mg/dL |  Consider neuromuscular/cardiac symptoms and other electrolytes. |  
 |  ABG pH |  7.35–7.45 |  Read together with PaCO_(2), bicarbonate and oxygenation. |  
 |  INR (not on warfarin) |  About 0.8–1.1 |  Confirm anticoagulant use, local policy and bleeding risk. |

These examples deliberately do not include a universal column of “panic values.”
Hospitals use locally defined critical-result criteria, and the required response
depends on the patient and clinical context. Full tables follow.

## Complete blood count (CBC/FBC) normal lab values

For detailed explanations of hemoglobin, RBC indices, white-cell differential, platelets,
specimens and practice cases, see our [complete blood count guide for nursing students](https://mynursinghub.com/cbc-blood-test-nursing/).
This section remains the quick reference chart.

A complete blood count (CBC), also called a full blood count (FBC), examines blood
cells and related indices. It commonly includes white cells, red cells, hemoglobin,
hematocrit, platelet count and red-cell indices. A CBC with differential also reports
different types of white blood cells. It can support assessment of bleeding, infection,
oxygen-carrying capacity, marrow function and treatment response.

  |  Test / marker |  Example adult reference interval |  Nursing meaning / what to assess |  
   |  WBC |  4.5–11.0 ×10^(9)/L |  Check fever, infection symptoms, steroid use, immunosuppression and trends. |  
 |  RBC, men |  4.6–6.2 ×10^(12)/L |  Interpret with hemoglobin and hematocrit, not alone. |  
 |  RBC, women |  4.2–5.4 ×10^(12)/L |  Consider blood loss, hydration, pregnancy and patient baseline. |  
 |  Hemoglobin, men |  13.8–17.2 g/dL |  Compare with oxygenation symptoms and active bleeding concerns. |  
 |  Hemoglobin, women |  12.1–15.1 g/dL |  Assess fatigue, breathlessness, bleeding symptoms and previous values. |  
 |  Hematocrit, men |  Approximately 40–55% |  Consider dehydration and blood loss context. |  
 |  Hematocrit, women |  Approximately 36–48% |  Read alongside hemoglobin and fluid status. |  
 |  MCV |  80–100 fL |  Lower MCV suggests a microcytic pattern; higher MCV suggests macrocytosis. |  
 |  MCH |  27–32 pg |  Describes average hemoglobin content per red cell. |  
 |  MCHC |  32–36 g/dL |  Describes average hemoglobin concentration in red cells. |  
 |  Platelets |  150–400 ×10^(9)/L |  Assess bruising, bleeding, medications and abnormal trends. |

### How do nursing students interpret CBC patterns?

**Read CBC results as a pattern.** Low hemoglobin with low MCV may support evaluation
for iron deficiency, but diagnosis requires additional clinical assessment and, 
often, iron studies. A high WBC does not by itself establish infection; a low WBC
can also be clinically important in an immunocompromised patient. A falling platelet
count deserves attention even before it reaches the bottom of an example interval
if the trend or symptoms are concerning.

The [iron-deficiency nursing guide](https://mynursinghub.com/iron-deficiency-anemia-nursing/)
discusses anemia patterns. Our [MPV blood test guide](https://mynursinghub.com/mpv-blood-test/)
covers mean platelet volume and why it must be interpreted with the platelet count.

Sample intervals are adapted for teaching from published CBC examples; confirm your
reporting laboratory’s intervals, especially for pregnancy, children and patients
with chronic conditions.

## Electrolyte lab values: sodium, potassium, chloride, bicarbonate, calcium and magnesium

Electrolytes are charged particles involved in fluid distribution, nerve impulses,
muscle activity and acid-base regulation. In nursing, the meaningful question is
not simply whether an electrolyte is above or below a memorized number but **what
that finding means for the patient’s observations, medications and ongoing fluid
balance**.

  |  Test / marker |  Example adult reference interval |  Nursing meaning / what to assess |  
   |  Sodium (Na^(+)) |  135–145 mmol/L |  Assess consciousness, confusion, seizure risk, fluid losses and medicines. |  
 |  Potassium (K^(+)) |  3.7–5.2 mmol/L |  Assess weakness, palpitations, renal function, medication history and ECG per protocol. |  
 |  Chloride (Cl^(−)) |  96–106 mmol/L |  Interpret with bicarbonate, sodium and fluid/acid-base context. |  
 |  Serum total CO_(2) / bicarbonate surrogate |  23–29 mmol/L (chemistry panel) |  Review metabolic acid-base context; not identical to direct ABG interpretation. |  
 |  Total calcium |  8.5–10.2 mg/dL (about 2.13–2.55 mmol/L) |  Review albumin, symptoms and whether ionized calcium is needed. |  
 |  Magnesium |  1.7–2.2 mg/dL |  Review muscle/neurological findings, renal function and relevant medicines. |

### Why are potassium and sodium important nursing lab values?

**Potassium is important for electrical activity in muscle and the heart.** A potassium
result should be reviewed in context of symptoms, kidney function, medications and
the specimen’s integrity. Hemolysis can falsely increase measured potassium, but
do not assume an unexpected result is harmless without a clinical and laboratory
assessment.

**Sodium is important for fluid and neurological balance.** Changes may accompany
altered water balance, medications or illness. A sudden neurological change is an
assessment and escalation concern even if a previous sodium level was within range.
Nurses should not initiate unsupervised electrolyte correction based on a cheat 
sheet.

For the related study concepts of osmotic movement and IV fluid tonicity, review
[isotonic, hypotonic and hypertonic solutions in nursing](https://mynursinghub.com/hypertonic-vs-hypotonic-solutions/).

## Basic metabolic panel (BMP) versus comprehensive metabolic panel (CMP)

**A BMP generally includes eight tests:** sodium, potassium, chloride, carbon dioxide(
bicarbonate-related measure), BUN, creatinine, glucose and calcium. A **CMP adds**
components such as total protein, albumin, bilirubin, alkaline phosphatase, ALT 
and AST. Exact panel composition can vary by health system and laboratory.

  |  Panel |  Typical tests included |  Best nursing study use |  
   |  BMP |  Glucose, calcium, sodium, potassium, chloride, CO_(2), BUN, creatinine |  Hydration, electrolytes, renal function and glucose context. |  
 |  CMP |  BMP tests plus albumin, total protein, bilirubin, ALP, ALT and AST |  Adds liver-related and protein measurements. |  
 |  CBC/FBC |  RBC, WBC, hemoglobin, hematocrit, platelets and indices |  Blood-cell patterns rather than electrolyte/organ chemistry. |

When reading a BMP or CMP, first identify which items are actually present on that
laboratory’s report. Do not refer to the whole CMP as a “liver function test”; many
components measure renal and electrolyte physiology, and even commonly described
liver “function” markers reflect different processes.

Nursing example: a patient with vomiting and reduced intake may have changes in 
several markers. Evaluate fluid balance and clinical observations, review whether
the sample and collection time are valid, and communicate the findings together 
instead of reporting each number as an isolated problem.

## Kidney function lab values: BUN, creatinine, eGFR and urine findings

Kidney-related laboratory markers help assess filtration, fluid balance and treatment
response. The most useful nursing pattern often combines **creatinine trend, urine
output, blood pressure, fluid status and medication exposure**. A single normal 
creatinine value does not rule out acute kidney injury in every person.

  |  Test / marker |  Example adult reference interval |  Nursing meaning / what to assess |  
   |  BUN |  6–20 mg/dL |  Can change with fluid status, renal function and protein-related factors. |  
 |  Serum creatinine |  0.6–1.3 mg/dL |  Interpret in context of age, muscle mass and prior results. |  
 |  eGFR |  Often ≥90 mL/min/1.73 m^(2) in younger healthy adults; no single universal age-independent “normal” threshold |  Assess trends and albuminuria; a value between 60 and 89 does not alone diagnose CKD. |  
 |  Urine albumin/creatinine ratio (ACR) |  Units and decision categories vary by region |  Assesses kidney damage in conjunction with eGFR and clinical history. |  
 |  Urine output |  Not a blood-test reference interval |  Record output pattern, fluid balance and hemodynamics. |

### Does a low eGFR always mean kidney disease?

No. eGFR is an estimate, and age, acute illness and other evidence matter. Chronic
kidney disease requires an appropriate clinical assessment, including persistence
or markers of damage. The [NHS kidney-disease testing guide](https://www.nhs.uk/conditions/kidney-disease/diagnosis/)
explains why eGFR categories are considered alongside other kidney findings.

Nursing example: a rising creatinine accompanied by falling urine output and low
blood pressure may require prompt assessment and escalation regardless of whether
the latest creatinine still falls inside an illustrative published interval.

## Liver function tests (LFTs): ALT, AST, ALP, bilirubin and albumin

The label “liver function tests” groups several distinct measurements. ALT and AST
are enzymes that may rise with cell injury. Alkaline phosphatase and bilirubin can
be affected by biliary or other processes. Albumin and clotting-related measurements
may reflect synthetic function, but they also have non-hepatic influences. Nurses
should note jaundice, bruising, medication exposure, symptoms and trends.

  |  Test / marker |  Example adult reference interval |  Nursing meaning / what to assess |  
   |  ALT |  4–36 U/L |  Consider liver-related illness, medicine history and repeat trends. |  
 |  AST |  8–33 U/L |  Not liver-specific; consider other tissues and the clinical picture. |  
 |  Alkaline phosphatase (ALP) |  20–130 U/L |  Interpret with liver, bile-duct and bone context. |  
 |  Total bilirubin |  0.1–1.2 mg/dL |  Assess jaundice and relevant symptoms with other results. |  
 |  Albumin |  3.4–5.4 g/dL |  Low values have multiple causes; consider illness, nutrition and losses. |  
 |  Total protein |  6.0–8.3 g/dL |  Interpret with albumin, globulins and hydration. |

These sample intervals are drawn from a published comprehensive metabolic panel 
and **may differ substantially** from an individual hospital’s assay-specific ranges.
Do not label an individual patient’s ALT “normal” without looking at the local range
and circumstances.

### Why do liver enzyme results need more than one lab value?

A single elevated enzyme is a finding, not a diagnosis. The overall pattern, trend,
medication review and symptoms help determine what should be communicated. When 
a patient has symptoms such as severe abdominal pain, jaundice, confusion or bleeding,
prioritize clinical assessment and local escalation over a nonurgent reference-chart
comparison.

## Glucose and HbA1c: reference values versus diagnostic cutoffs

Glucose and HbA1c are particularly important because some common values are **clinical
diagnostic decision limits rather than ordinary laboratory reference intervals**.
For nursing study, distinguish a fasting plasma glucose measurement from a random
reading, and distinguish diabetes screening from a treatment target in a person 
already diagnosed with diabetes.

  |  Glucose-related result |  Published decision criterion |  Nursing significance |  
   |  Fasting plasma glucose |  Below 100 mg/dL (<5.6 mmol/L) in current US diagnostic criteria |  Confirm fasting status; assess symptoms and treatment context. |  
 |  Prediabetes fasting range |  100–125 mg/dL (5.6–6.9 mmol/L) |  A screening/diagnostic category, not an acute bedside treatment target. |  
 |  Diabetes fasting cutoff |  ≥126 mg/dL (≥7.0 mmol/L), generally requiring confirmation when appropriate |  Clinician-led interpretation and confirmation. |  
 |  HbA1c below prediabetes threshold |  <5.7% |  Reflects average glycemia over roughly 2–3 months; may be affected by red-cell conditions. |  
 |  Prediabetes HbA1c |  5.7–6.4% |  Decision category for assessment; not a universal therapeutic goal. |  
 |  Diabetes HbA1c threshold |  ≥6.5%, with confirmation requirements |  Diagnostic criterion for eligible assays and settings. |

The [American Diabetes Association diagnostic criteria](https://diabetes.org/about-diabetes/diagnosis)
distinguish these categories. HbA1c can be misleading in some forms of anemia, recent
blood loss, transfusion and other conditions. If symptoms and test results conflict,
report the discrepancy rather than reassuring a patient on the basis of one value.

For inpatient nursing, glucose monitoring frequency and escalation thresholds depend
on the care setting, patient condition and approved orders. Never use screening 
thresholds as instructions for insulin administration.

## Coagulation lab values: PT, INR and aPTT

Coagulation tests assess different parts of the clotting system. **PT and INR** 
are commonly considered together; **aPTT** evaluates another part of the pathway.
Anticoagulant therapy can change expected findings. The same result can have different
significance in a patient receiving warfarin, heparin or no anticoagulant.

  |  Test / marker |  Example adult reference interval |  Nursing meaning / what to assess |  
   |  Prothrombin time (PT) |  Approximately 11–13.5 seconds in people not using anticoagulants |  Check bleeding, bruising, liver-related context and therapy. |  
 |  INR, not taking warfarin |  Approximately 0.8–1.1 |  Interpret differently when warfarin or another relevant condition is present. |  
 |  aPTT / PTT |  Approximately 25–35 seconds |  Local assay and heparin-related protocols matter. |  
 |  D-dimer |  No single range suitable for all assays and age-adjusted pathways |  Use only within the specified diagnostic pathway; not a standalone diagnosis. |

Some patients on warfarin have an individualized therapeutic INR target that intentionally
differs from the non-anticoagulated reference interval. Nurses verify the medication
record, observe bleeding or clotting concerns, and follow the ordered monitoring
and escalation pathway rather than adjusting anticoagulants independently.

## Arterial blood gas (ABG) normal values for nursing students

An arterial blood gas reports oxygenation and acid-base measurements. In a nursing
assessment, read **pH, PaCO_(2) and bicarbonate together**, then review PaO_(2),
oxygen saturation, oxygen delivery and the patient’s respiratory condition. Do not
treat an ABG as interchangeable with a venous sample or pulse oximetry.

  |  Test / marker |  Example adult reference interval |  Nursing meaning / what to assess |  
   |  pH |  7.35–7.45 |  Acidemia below the lower bound; alkalemia above the upper bound. |  
 |  PaCO_(2) |  35–45 mmHg |  Reflects respiratory contribution to acid-base status. |  
 |  HCO_(3)^(−) |  22–26 mEq/L |  Reflects metabolic contribution. |  
 |  PaO_(2) |  75–100 mmHg in one widely used adult reference |  Interpret with age, oxygen supplied, altitude and condition. |  
 |  SaO_(2) |  95–100% in a typical reference |  Relate to clinical assessment; do not confuse with SpO_(2). |

### What do abnormal ABG values mean for nurses?

An acid-base abnormality should trigger a structured patient assessment and communication
proportional to severity and symptoms. In a breathless patient, review respiratory
rate, effort, mental state, oxygen delivery, SpO_(2) and the medical plan. An ABG
is one source of information and must be integrated into the clinical picture. See
the [vital-sign assessment and escalation guide](https://mynursinghub.com/clinical-procedures-notes-for-nursing-students/patients-vital-signs-assessment-and-escalation/)
for the bedside observation workflow.

The example intervals are consistent with [MedlinePlus ABG guidance](https://medlineplus.gov/lab-tests/arterial-blood-gas-abg-test/);
individual laboratories and clinical circumstances can differ.

## Urinalysis normal values and bedside nursing significance

Urinalysis commonly assesses appearance, chemical markers and sometimes microscopic
findings. A urine dipstick may detect glucose, protein, blood, leukocyte esterase
and nitrite. A negative or positive strip result is only part of a clinical assessment,
and collection technique or contamination may alter the sample.

  |  Test / marker |  Example adult reference interval |  Nursing meaning / what to assess |  
   |  Urine specific gravity |  1.005–1.030 |  Relate concentration to intake, output and the patient’s fluid state. |  
 |  Glucose |  Usually not detected on routine dipstick |  Positive result needs relevant clinical correlation. |  
 |  Protein |  Usually negative/trace on routine dipstick, method dependent |  Persistent positive result may prompt quantitative testing. |  
 |  Nitrite |  Usually negative |  A positive result may support evaluation of infection but does not establish a diagnosis. |  
 |  Leukocyte esterase |  Usually negative |  Interpret with symptoms, other urine markers and collection quality. |  
 |  Blood / hemoglobin |  Usually negative |  Review menstruation, contamination, symptoms and other causes. |

Urine specimens should be labeled according to local identification policy and transported
promptly with appropriate handling. A positive nitrite or leukocyte result in a 
patient without symptoms is not automatically an indication for antibiotics. Use
the clinical assessment and the prescribing team’s pathway.

## Critical lab values: what nurses must recognize and report

**Critical laboratory values are not just “very abnormal” results.** They are results
classified by a laboratory and healthcare organization for urgent communication 
under a defined policy. Critical limits can differ among hospitals, age groups and
clinical contexts. A printed textbook table must not replace the laboratory’s actual
alert criteria.

 * Confirm the patient’s identity, specimen collection time and the reported result.
 * Assess immediate symptoms, vital signs and safety concerns rather than focusing
   solely on the number.
 * Notify the appropriate clinician or rapid-response pathway according to institutional
   policy.
 * Use an organized handoff such as SBAR when appropriate, with a read-back or closed-
   loop communication where required.
 * Document the time, result, contact, instructions and follow-up assessment according
   to local policy.

Example: if an unexpectedly high potassium result is flagged by the laboratory, 
the nursing assessment can include symptoms, relevant medications, kidney history,
ECG indications, previous results and whether the specimen was hemolyzed. Do not
dismiss the result as a sample error without appropriate verification and escalation.

## How to study lab values without confusing units or reference ranges

Memorization is easier when values are grouped by **clinical purpose** instead of
learned as one long alphabetic list. This method also helps avoid keyword-heavy 
study material that students cannot actually use in placement or examination scenarios.

 * **Blood cells:** WBC, RBC, Hb, Hct, MCV, platelets.
 * **Electrolytes:** sodium, potassium, chloride, bicarbonate, calcium, magnesium.
 * **Kidney:** BUN, creatinine, eGFR and urine trends.
 * **Liver:** ALT, AST, ALP, bilirubin, albumin and total protein.
 * **Clotting:** PT, INR, aPTT, and anticoagulant context.
 * **Gas exchange and acid-base:** ABG pH, PaCO_(2), HCO_(3)^(−), PaO_(2).

Use active recall: hide the reference-interval column, name the unit, then answer“
What should I assess if this result changes?” Next, compare a hypothetical current
value with an earlier result. This teaches pattern recognition without prescribing
treatment based on a memorized number.

Be careful with unit conversion. Hemoglobin may be shown in g/dL or g/L; creatinine
may be shown in mg/dL or µmol/L; platelets may be shown as ×10^(9)/L or per microliter.
Always name the unit when writing a value.

![Hand-drawn nursing lab-values cheat sheet showing blood count, electrolyte, kidney
and liver test groups with a result-to-range-to-trend-to-patient-to-report workflow.](
https://mynursinghub.com/wp-content/uploads/2026/10/nursing-lab-values-cheat-sheet-
hand-drawn-cbc-electrolytes-kidney-and-liver-diagram-webp.webp)

A study map of four common laboratory panels and a nurse’s result-to-patient assessment
sequence. The complete reference numbers are in the accessible tables above.

## Worked nursing examples: connecting patterns to assessment

### Case 1: falling hemoglobin after surgery

An adult postoperative patient has a hemoglobin result lower than the previous day’s
value. The student should ask whether the patient has dizziness, shortness of breath,
pallor, new bleeding, tachycardia or a blood-pressure change. Confirm the specimen
timing, assess observations and fluid balance, review the procedure and communicate
the trend and patient findings to the clinical team. The numerical interval is background;
the change in the patient and its timing determine urgency.

### Case 2: high potassium with a possible specimen problem

An adult patient has a potassium value flagged high and a laboratory comment about
hemolysis. First assess whether the patient is symptomatic or unstable, verify the
result and specimen details through the approved process, review renal history and
medicines, and follow local escalation guidance. Hemolysis may produce a spurious
result, but the flag should never be ignored solely because a repeat sample might
be needed.

### Case 3: glucose and HbA1c tell different stories

A patient has an elevated HbA1c but a single fasting glucose reading that is not
high. The two measures reflect different time frames. Review the timing, symptoms
and factors that may affect HbA1c, and report the mismatch for appropriate clinician
interpretation rather than trying to diagnose diabetes from one number.

### Case 4: normal WBC despite concerning symptoms

A patient reports worsening breathlessness and appears acutely unwell, but the WBC
result is inside the laboratory’s reference interval. A normal WBC does not rule
out serious illness. Assess and escalate the patient’s clinical condition according
to the local emergency pathway, without waiting for the laboratory value to change.

## Practice questions with answers for nursing students

### 1. A patient’s hemoglobin falls while pulse rises. What matters most?

**Answer:** Assess the patient for symptoms and bleeding, verify observations and
trend, and escalate the combined finding. A reference range alone does not determine
priority.

### 2. Why is potassium not interpreted in isolation?

**Answer:** The result may be affected by medicines, renal function, symptoms and
sample hemolysis. Cardiac evaluation and communication may be indicated by the clinical
situation.

### 3. Does an INR reference interval apply to a patient taking warfarin?

**Answer:** No. A patient on warfarin may have a prescribed therapeutic target that
differs from the non-anticoagulated interval.

### 4. What is the first step when a result appears inconsistent with the patient?

**Answer:** Check the patient, units, collection time, specimen details and earlier
results, and follow the appropriate clinical escalation and laboratory verification
process.

## Frequently asked questions about normal lab values for nurses

### What are the normal lab values for nurses to memorize?

Start with CBC, sodium, potassium, glucose, BUN, creatinine, coagulation tests and
ABG components. Memorize the _unit and purpose_ as well as the approximate interval;
your workplace laboratory range takes precedence over a general chart.

### What is a normal laboratory value?

It is a result within a reference interval defined for a particular test method 
and population. It does not guarantee the absence of disease.

### What are normal CBC lab values for adults?

Common examples include WBC around 4.5–11.0 ×10^(9)/L, platelets around 150–400 
×10^(9)/L and MCV around 80–100 fL. Hemoglobin and some other values vary by sex,
age and laboratory.

### What is the normal sodium level?

A commonly published serum sodium interval is 135–145 mmol/L. Interpret sodium alongside
fluid status, neurological findings, medication exposure and the reporting laboratory’s
range.

### What is the normal potassium level?

Published reference intervals vary; one common chemistry panel uses about 3.7–5.2
mmol/L. Potassium findings matter for muscle and cardiac physiology and require 
context, including specimen integrity.

### What are normal electrolyte levels in nursing?

Electrolyte panels commonly include sodium, potassium, chloride and bicarbonate;
calcium and magnesium may be ordered separately. Study their units and physiological
roles together rather than as unrelated numbers.

### What is the difference between a BMP and CMP?

A BMP usually covers electrolytes, glucose, calcium, BUN and creatinine. A CMP adds
protein and liver-related analytes such as albumin, bilirubin, ALP, ALT and AST.

### What are normal kidney function values?

BUN and creatinine have laboratory-specific reference intervals; eGFR interpretation
also depends on age, other kidney findings and duration of abnormalities. The trend
and urine output may be clinically important.

### Is an eGFR of 60–89 always abnormal?

No. A value in that range does not by itself diagnose chronic kidney disease. A 
clinician considers age, albuminuria, other evidence of kidney damage and whether
the finding persists.

### What are normal liver function test values?

There is no single universal panel range. ALT, AST, ALP, bilirubin, albumin and 
total protein have method-specific intervals, and their patterns have different 
meanings.

### What is normal HbA1c?

An HbA1c below 5.7% is below the US prediabetes threshold. HbA1c 5.7–6.4% is a prediabetes
category, and 6.5% or higher is a diabetes diagnostic criterion when confirmation
and assay requirements are satisfied.

### What is a normal INR?

In a person not taking warfarin, a common example is about 0.8–1.1. Anticoagulated
patients may have a different prescribed therapeutic target.

### What are normal ABG values?

Typical adult ABG study values are pH 7.35–7.45, PaCO_(2) 35–45 mmHg and HCO_(3)
^(−) 22–26 mEq/L, with PaO_(2) interpreted in the oxygenation context.

### What does H or L mean next to a blood test?

H means the result is above the report’s reference interval and L means it is below.
Neither letter establishes a diagnosis or automatically indicates a clinical emergency.

### Are critical lab values the same in every hospital?

No. Laboratories and healthcare systems establish critical-result limits and communication
policies. Nurses must use their facility’s approved notification and escalation 
process.

### Can normal blood test results mean a patient is still ill?

Yes. A laboratory result may be within a reference interval even when a patient 
has symptoms or a serious condition. Bedside assessment remains essential.

### Where can nursing students find a lab values cheat sheet?

The quick-reference chart near the top of this guide groups common adult values,
with detailed tables for each panel below. Treat cheat sheets as revision aids, 
not substitutes for the reporting laboratory’s reference interval.

### How should a nurse respond to a critical laboratory result?

Verify the patient and report, assess the patient, communicate through the designated
pathway, document closed-loop follow-up, and reassess according to the clinical 
plan and local policy.

## Related nursing study guides

Continue with the [blood test and lab-result interpretation guide](https://mynursinghub.com/interpreting-lab-results-nursing/)
for step-by-step reasoning, critical-result escalation and specimen preparation.
For more focused topics, study [MPV blood tests](https://mynursinghub.com/mpv-blood-test/),
[iron deficiency and hemoglobin patterns](https://mynursinghub.com/iron-deficiency-anemia-nursing/),
[IV fluid tonicity](https://mynursinghub.com/hypertonic-vs-hypotonic-solutions/)
and [vital-sign assessment](https://mynursinghub.com/clinical-procedures-notes-for-nursing-students/patients-vital-signs-assessment-and-escalation/).

For evidence behind reference intervals, the [MedlinePlus explanation of laboratory results](https://medlineplus.gov/lab-tests/how-to-understand-your-lab-results/)
is a useful clinical reference, but the numerical ranges printed on a patient’s 
own laboratory report remain the appropriate comparison.