Critical Values

Anion Gap

Any age

>30

mmol/L

Bicarbonate (Whole Blood)

Any age

<10
>40

mEq/L

Calcium *

Any age

<6.5
>13

mg/dL

Chloride

Any age

<80
>120

mmol/L

CO2

Any age

<10
>40

mmol/L

CO Hemoglobin

Any age

>20

%

Free (ionized) Calcium *

Any age

<0.8
>1.6

mmol/L

Creatinine

1-28 days

5weeks-23mo

2y-11y

12y-15y

Adults

≥1.5

≥2

≥2.5

≥3

≥10

mg/dl

Digoxin

Any age

≥4

ng/ml

Glucose

0-2 days
>2 days &<1 year
>1 year

<35
<40
<55

mg/dL

Glucose

<30 days
>30 days &<17 yrs
>17 yrs

>200
>300
>450

mg/dL

Glucose (GDM)
GDM Glucose Tolerance
GMD Glucose Tolerance 1hr
GMD Glucose Tolerance 2hrs
GMD Glucose Tolerance 3hrs

Any age

<50
>300

mg/dL

Glucose

PXP Glucose meter (POCT)

Any age

<40
>300

mg/dL

Iron, Serum

Any age

≥350

ug/dL

Magnesium

Any age

<1.0
>3.5

mg/dL

pCO2

Any age

>65

mmHg

pH

Any age

<7.20
>7.60 

pH units

pH – Arterial & Venous Blood Gases, Cord Blood

Any age

<= 7.00

N/A

Base Excess – Arterial & Venous
Blood Gases, cord blood

Any age

<= -10.0
= >10.0

mmol/L

Phosphorus

<3 years of age
3-12 years of age
>12 years of age

≤2.5
≤2.0
≤1.5

mg/dL

pO2 (arterial)

Any age

<50

mg/dL

Potassium

Less than 1 week
Older than 1 week
Any age

<2.5
<3.0
>6.0

mmol/L

Potassium;
ISTAT (POCT)

Any age

<3.0
>6.0

mmol/L

Sodium

Any age
Any age

<125
>160

mmol/L

TCO₂ (Whole Blood)

Any age

<10
>40

mEq/L

Total Bilirubin

<1 day
>1 day <2 days
>2 days <30 days

≥7
≥11
≥15 

mg/dL

Troponin I

Any age

≥0.3 

ng/mL

Troponin I:
ISTAT (POCT)

Any age

≥0.1

ng/mL