Ranges and Formulas

Keep in mind that reference ranges are established for different populations (geographical, male/female, and age) so check with your facility for exact limits. These values are only meant as a general guideline.

Total Protein 6.0-8.0 g/dL
Albumin 3.5-5.0 g/dL
BUN 6-20 mg/dL
Creatinine Male: 0.9-1.3 mg/dL

Female 0.6-1.1 mg/dL
BUN/C Ratio >20: pre-renal

10-20: renal

10-20: post-renal

<10: hepatic
eGFR >60 mL/min/1.73mm2
Random Blood Glucose <200 mg/dL
Fasting Blood Glucose 74-100 mg/dL

<40 mg/dL

>400 mg/dL

DM: >125 mg/dL
2hr OGTT  <140 mg/dL

DM: > 200 mg/dL
A1C 4.0-5.5%

DM: 6.5%
AST 5-35 U/L
ALT 7-45 U/L
ALP 45-130 U/L
CK-MB <6%
Troponin I <10 ng/mg
Iron <10 ng/mL
Bilirubin, Total 0.2-1.0 mg/dL

>20 mg/dL
Na 136-145 mmol/L

<120 mmol/L

>160 mmol/L
K 3.5-5.1 mmol/L

<2.9 mmol/L

>6 mmol/L
Cl 98-107 mmol/L
HCO3 23-29 mmol/L
Anion Gap 10-20 mmol/L
Osmole Gap 5-10 mOsm/kg
Calcium, Total 2.15-2.5 mmol/L

<1.60 mmol/L

>3.25 mmol/L
Magnesium 0.66-1.07 mmol/L
pH Venous: 7.32-7.42

Arterial: 7.35-7.45

<7.2

>7.6
ppCO2 35-45 mmHg
ppO2 >80 mmHg
TSH 0.3 -5.0 uU/L

Formulas:

Concentration conversion: M1V1=M2V2

Average: x̅ = Σ x1+x2+xn…/n

Variance: σ2 = Σ [(x1-x̅)2+(x2-x̅)2+(xn-x̅)2+…]/(n-1)

Std Dev: σ = √{Σ [(x1-x̅)2+(x2-x̅)2+(xn-x̅)2+…]/(n-1)}

% CV: = σ/ x̅

A/G Ratio: = albumin/(total protein – albumin)

De Ritis Ratio: = AST / ALT

GFR: = [creatinineurine × flowurine(ml/min) × 1.73(m2)] / [creatinineblood × body surface (m2)]

eGFR per 1.73m2: = 175 × creatinineurine-1.154 × Age‑0.0203 × 1.212ifblack × 0.742iffemale

U/C Ratio: = blood urea nitrogen / creatinine

Friedewald VLDL: = triglyceride / 5

LDL: = total cholesterol – HDL – VLDL

NonHDL: = LDL + VLDL

TIBC: = serum iron – UIBC

% Iron Saturation: = Ironserum/TIBC

Unconjugated Bili: = total bili – conjugated bili

Osmolality, Calc: = (2 × Na) + (glucose / 20) + (BUN / 3)

Osmole Gap: = |calculated osm – measured osm|

Anion Gap: = Na + K – Cl – HCO3

Henderson-Hasselbalch (Blood Gas): = 6.1 + log ([HCO3] / 0.0307 / ppCO2)

HCO3: = 10(pH – 6.1) × ppCO2 × 0.0307

https://iamacc.co.ihc.com/labnet/cm/ref_ranges.php