CBC Lab Values

Question 1

WBC
White Blood Cell
Reference Value

Answer 1

5.0 - 10.0 10^9/L

Question 2

Leukocytosis Value
and
Approach

Answer 2

> 11.0 10^9/L

Symptom based approach, especially in presence of fever.

Question 3

Leukopenia Value
and
Approach

Answer 3

<4.0 10^9/L

Symptom based approach, especially in presence of fever.

Question 4

Neutropenia Value
and
Approach

Answer 4

<1.5 10^9/L

Symptom based approach, especially in presence of fever.

Question 5

Platelets Reference Value

Answer 5

140 - 400 k/uL

Question 6

Thrombocytosis Value
and
Approach

Answer 6

> 450 k/uL
Symptom based approach.
Can lead to VTE (venous thromboembolism) (includes DVT and pulmonary embolism).

Question 7

Thrombocytopenia Value
and
Approach

Answer 7

<150 k/uL

Fall risk awareness; risk of spontaneous hemorrhage

Question 8

Severe Thrombocytopenia Value
and
Approach

Answer 8

<20 k/uL

Symptom based approach; possible need for transfusion prior to mobilization.

Question 9

Hemoglobin Reference Value

Answer 9

Female: 12 - 16 g/dL
Male: 14 - 17.4 g/dL

Question 10

Polycythemia Value
and
Approach

Answer 10

>20 g/dL hemoglobin
Symptom based approach.  Can lead to clogging of capillaries.
OR
>60% hematocrit
Spontaneous blood clotting.

Question 11

Anemic Hemoglobin Value
and
Approach

Answer 11

<8 g/dL
Symptom based approach, possible need for transfusion prior to mobilization.
<5-7 g/dL can lead to heart failure or death.

Question 12

Note that in the elderly, these values may be slightly decreased.

Answer 12

Hemoglobin
and
Hematocrit

Question 13

How does time of day affect WBC count?

Answer 13

Lower in the early AM, high peak in late afternoon.

Question 14

At this level, hospitalized patients who are hemodynamically stable and asymptomatic may transfuse.

Answer 14

Hemoglobin 7 g/dL

Question 15

At this level, post-op cardiac or orthopedic patients and those with underlying cardiovascular disease may transfuse.

Answer 15

Hemoglobin 8 g/dL

Question 16

Hematocrit Reference Value

Answer 16

Female: 37 - 47%
Male: 42 - 52%

Question 17

Anemic Hematocrit Value
and
Approach

Answer 17

<25% symptom based approach, possible need for transfusion prior to mobilization.

Question 18

Important to monitor SpO2 to predict tissue transfusion when pt is anemic due to:

Answer 18

Tachycardia and orthostatic hypotension.