SEvidence-Based Practicum

Interactive Reference

Clinical Lab Values

Click any lab to review what it measures, causes of abnormal results, clinical considerations, and an authoritative external reference.

Electrolytes

Potassium (K⁺): 3.5 – 5.0 mEq/L
Sodium (Na⁺): 135 – 145 mEq/L
Calcium, total: 8.6 – 10.2 mg/dL
Calcium, ionized: 4.5 – 5.5 mg/dL
Magnesium (Mg²⁺): 1.3 – 2.0 mEq/L
Phosphorus: 3.0 – 4.5 mg/dL
Chloride (Cl⁻): 96 – 106 mEq/L

Clinical focus

•Report K⁺ < 2.5 or > 6.0 immediately
•Na⁺ < 120 or > 160 is critical
•Trend with I&O and daily weights

Renal Function

BUN: 10 – 20 mg/dL
Creatinine: 0.6 – 1.3 mg/dL
BUN / Cr ratio: 10:1 – 20:1
eGFR: > 90 mL/min/1.73m²

Clinical focus

•Downward eGFR trend = kidney dysfunction
•Avoid nephrotoxic meds (NSAIDs, contrast)
•Monitor I&O and daily weight

ABG (Room Air)

pH: 7.35 – 7.45
PaCO₂: 35 – 45 mmHg
PaO₂: 80 – 100 mmHg
HCO₃⁻: 22 – 26 mEq/L
SaO₂: 95 – 100%

Acid–Base quick guide

pH ↓ acidosis · pH ↑ alkalosis
PaCO₂ ↑ respiratory acidosis · ↓ respiratory alkalosis
HCO₃⁻ ↓ metabolic acidosis · ↑ metabolic alkalosis

Open ABG interpreter →

Hematology (CBC)

WBC: 4.0 – 11.0 K/µL
RBC: 4.2 – 6.0 M/µL
Hemoglobin: 12 – 18 g/dL
Hematocrit: 37 – 52%
Platelets: 150 – 400 K/µL

Clinical focus

•Fever + ↑ WBC = infection
•Low platelets = bleeding risk
•Trend Hgb/Hct for anemia or blood loss

WBC Differential

Neutrophils(50–70%): 3,000 – 7,000
Lymphocytes(20–40%): 1,000 – 4,000
Monocytes(2–8%): 200 – 800
Eosinophils(1–4%): 50 – 500
Basophils(0–1%): 0 – 100

Clinical focus

•↑ Neutrophils → bacterial infection
•↑ Lymphocytes → viral infection
•↑ Eosinophils → allergies, parasites

Liver Function

AST: 10 – 40 U/L
ALT: 7 – 56 U/L
Alk phosphatase: 30 – 120 U/L
Total bilirubin: 0.3 – 1.0 mg/dL
Albumin: 3.5 – 5.5 g/dL
Total protein: 6.0 – 8.3 g/dL

Clinical focus

•Assess jaundice, pruritus, RUQ pain
•Avoid hepatotoxic drugs (acetaminophen limits)
•Monitor mental status for encephalopathy

Coagulation

PT: 11 – 13.5 sec
INR(no anticoag): 0.8 – 1.1
PTT: 25 – 35 sec
Platelets: 150 – 400 K/µL

Clinical focus

•Assess for bleeding & bruising
•Monitor anticoagulant therapy closely
•Report critical values immediately

Lipid Panel

Total cholesterol: < 200 mg/dL
HDL (good): > 60 mg/dL
LDL (bad): < 100 mg/dL
Triglycerides: 35 – 150 mg/dL

Glucose

Fasting: 70 – 110 mg/dL
Random: < 140 mg/dL
A1C: < 5.7% normal

Clinical focus

•Assess diet & exercise
•Administer meds/insulin as ordered
•Monitor for hypo/hyperglycemia signs

Vital Signs (Adult)

Temp: 97.0 – 99.5 °F
Heart rate: 60 – 100 bpm
Blood pressure: 90/60 – 120/80 mmHg
Respiratory rate: 12 – 20 /min
SpO₂: ≥ 94%

Critical — Report Now

Potassium: < 2.5 or > 6.0 mEq/L
Sodium: < 120 or > 160 mEq/L
Calcium: < 7.5 or > 12 mg/dL
Hemoglobin: < 7 or > 20 g/dL
Platelets: < 20K or > 1,000K
pH: < 7.25 or > 7.55
Glucose: < 50 or > 400 mg/dL

Abbreviations

ABG — arterial blood gas
CBC — complete blood count
BMP — basic metabolic panel
CMP — comprehensive metabolic
I&O — intake & output
LOC — level of consciousness
PRN — as needed
WNL — within normal limits

Always correlate labs with the whole clinical picture. If it doesn't look right, speak up.