Lab Values 2026

Why do we need to know lab values?

--Important to monitor

----Electrolyte and blood cell counts will impact the intensity and appropriateness of therapy for that day

--Need to know normal ranges as well as critically low values

--Trends matter as much as the value at any given time

Lab Value considerations

Age - Norms created based on healthy people, considerations for mobility based on age and current medical condition

Patient's biological sex, gender, and gender identity

HRT (reference values)

No HRT biological sex

Why use a Symptoms-based approach?

-Mobility of patients along a progressive continuum

---Readiness

---Specific pathology

---Prevent complications

---Activity tolerance

-Plethora of studies supporting early mobilization as safe and feasible

-Minimize readmissions

What does reference range AKA normal range depict?

-Homeostasis

-Varies with age, sex, wt, fluid status, physiologic changes

-Individuals w/ different tolerances

Not meant to be memorized, look at TRENDS

Critical values

"A value/result that represents a pathophysiological state at such variance with normal (expected values) as to be life-threatening unless something is done promptly and for which some corrective action could be taken"

AKA when to panic over abnormal values

Common Lab Screening Profiles

CBC, Electrolyte Panel, Metabolic Panel, Kidney function, Liver function, Cardiac Models, and Lipid panel

Complete Blood Count (CBC)

Screens for anemia, infections, coagulation disorders

RBC, Hgb, Hct, platelet count, WBC, and WBC differential, PTT, INR

Electrolyte panel measures

Na+, K+, Cl-, CO2, pH

Metabolic panel measures

Na+, K+, Cl-, CO2, glucose, BUN, creatinine

Kidney function measures

BUN, creatinine, creatinine clearance, glucose, Ca2+, CO2

Liver function measures

Total bilirubin, alkaline phosphatase, aspartate aminotransferase (AST), gamma glutamyl transferase(GGT), lactate dehydrogenase (LDT), prothrombin (PT), total protein, albumin

Cardiac markers measures

Cardiac troponins, creatine kinase (CK), beta-type natriuretic peptide (BNP), C-reactive protein (CRP),homocysteines

Lipid panel measures

Cholesterol, HDL, LDL, VLDL, triglycerides

Reference value for WBCs

5.0-10.0X10^9/L

Leukocytosis

increase in the number of white blood cells

Trending up > 11.0 x 10^9/L

Causes of Leukocytosis

infection, leukemia, obesity, inflammation, stress/pain

Clinical presentation of Leukocytosis

weakness, fatigue, fever, dizziness, etc.

Consider timing therapy around early morning low level and late afternoon high peak

Leukopenia/Neutropenia

decreased WBCs

Trending down

Platelets reference value

140-400 k/uL

Platelets trending down

<150 k/ul; excessive bleeding can occur

Potential causes of Platelets downward trend

infection, leukemia, radiation/chemo, liver disease

Clinical Presentation of downward trend of Platelets

bruising, petechiae, fatigue, jaundice

Platelets trending up

>450 k/uL (thrombocytosis)

Potential causes of Platelets upward trend

inflammation, cancer, stress, infection

Clinical Presentation of upward trend of Platelets

weakness, headache, dizziness, chest pain

Therapy implication of < 10,000 platelets and/or temp >100.5 deg

Hold therapy

Is pt a fall risk if outside CBC reference value?

Yes, increased spontaneous hemorrhage

What is hemoglobin?

Oxygen carrying pigment in red blood cells

Reference value of Hemoglobin

Men 14-17.4 g/dL; Women 12-16 g/dL

Critical values of Hemoglobin

< 5-6 g/dl or > 20 g/dL

What are causes of Hemoglobin trending up?

CHF, dehydration, COPD, severe burns

What is the clinical presentation of Hemeglobin trending up?

Dizziness, arrhythmias, TIA symptoms, Chest pain

What are causes of Hemoglobin trending down?

Anemia, blood loss, lupus, kidney disease, stress to bonemarrow

What is the clinical presentation of Hemeglobin trending down?

decreased endurance, pallor, tachycardia

Therapy implications for Hemoglobin

-Facility dependent, Generally <8 g/dL: essential ADLs only, hold out of bed activity

-BUT there are pt's with chronically low Hgb ---> symptoms-based approach

Hematocrit reference values

Male: 42-52%

Female: 37-47%

Critical values for Hematocrit

<15-20% or >60%

Hematocrit trending up causes

COPD, burns, CHF, dehydration

High Hematocrit clinical presentation

fever, HA, dizziness, weakness, fatigue

Hematocrit trending down causes

leukemia, multiple myeloma, pregnancy, cirrhosis, RA

Low hematocrit clinical presentation

Pale skin, HA, dizziness, chest pain,arrhythmia, dyspnea

Therapy implications of Hematocrit

Prothrombin Time (PT)

Evaluates blood's ability to clot

Normal 10-12 sec

coumadin 25+ seconds high risk for bleeding

Partial Thromboplastin Time (PTT) or activated APTT

Used to determine if heparin/warfarin (blood thinner) therapy is effective

Normal 30-45 sec (22-31)

International Normalized Ratio (INR)

Measure of how long it takes the blood to clot when an oral anticoagulant is used

PT and PTT values can differ lab to lab

Normal 0.8-1.2

What happens if the INR is above the range?

-If above the range, there is an increased risk for bleeding and if lower, there is an increased risk for clotting

-Those on anticoagulants will have higher INRs