Labs & Diagnostics

Question 1

What is measured in a CBC (complete blood count)

Answer 1

• WBC’s
• Hemoglobin (Hgb)
• Platelets (Plt)
• Hematocrit (Hct)

Question 2

Normal WBC count is…

Answer 2

3.5-12 x 10(9)/L

Question 3

Normal Hgb count is…

Answer 3

Males: 140-180
Females: 120-160

Question 4

Normal platelet count is…

Answer 4

150-400 x 10(9)/L

Question 5

Normal Hct is…

Answer 5

Males: 0.4-0.55
Females: 0.37-0.55

Question 6

Extended electrolytes and their normal values

Answer 6

Ca++ 1.15-1.35 mmol/L
Mg++ 0.8-1.2 mmol/L
PO4 1-1.5 mmol/L

PO4 = Phosphate

Question 7

What is measured on a BMP
(basic metabolic panel),
and what are their normal values?

Answer 7

• Na+ 135-145 mmol/L
• K+ 3.5-5.1 mmol/L
• Cl- 96-106 mmol/L
• HCO3 23-29 mmol/L
• Urea 2.9-8.2 mmol/L (increases signify dehydration)
• Creatinine 50-100 umol/L (increases signify damage)
• BgL 4.4-6.1 mmol/L

Question 8

What are ABG ratios when looking for superimposition?

Answer 8

Metabolic acidosis HCO3:PaCO2 = 1:1
Metabolic alkalosis HCO3:PaCO2 = 1:0.7
Respiratory alkalosis PaCO2: HCO3 = 1:0.5
Respiratory acidosis PaCO2:HCO3 = 1:0.3

Question 9

How is an anion gap calculated?

Answer 9

Na+ - (Cl- + HCO3)
normal is 8-12 mEq/L

Question 10

What causes AGMA?

Answer 10

Increasesd anions (Cl- & HCO3) or decreased cations (Na+ or K+) will cause AGMA, however if there is still a large differential after AG is calculated, the acronym KULTS MUDPILES can be used to assist in finding a cause:

• Keytones
• Uremia
• Lactate
• Toxic alcohols
• Salicylates
  .
• Methanol
• Uremia
• DKA
• Paraldehyde
• Iron/INH
• Lactate
• Ethelyne glycol
• Salicylates

Question 11

What is a normal troponinlevel?

Answer 11

Normal is 0-0.04 ng/mL
Increases over 0.4 ng/mL should raise suspicion of cardiac etiology.
Detectable within 3-6 hours of insult, and returns to normal within 10-15 days.

Question 12

What is the significance of BNP
(B-type naturieretic peptide)

Answer 12

As it’s produced by cardiac muscle, it’s usually a sign of heart failure, however, elevated levels can be caused by kidney failure and PE/pulmonary hypertension.

Levels over 100pg/mL are considered abnormal, and >400pg/mL are indicitave of severe heart failure.

Question 13

When would CK-MB be tested?

Answer 13

CK-MB is an enzyme specific to cardiac muscle. Elevated levels appear within 4-8 hours of myocardial damage. This is helpful in determining whether post MI angina is due to extending damage.

Question 14

What are the components of a RUSH exam?

Answer 14

Heart: look for effusion, LV fx., RV strain, LVOT
IVC: collapsed or full?
Morrison’s pouch for effusion or hemiperitoneum
Aortic aneurysm or dissection
Pulmonary: PTX or effusion

Question 15

Which views are particular to an eFAST exam?

Answer 15

RUQ (Morrison’s pouch)
Pelvis (bladder)
LUQ (suprasplenic)
Pericardium
Lung slide