PA Prof: Labs and Radiology

What does a "Left Shift" in a WBC differential typically imply?

 Increase in Segmented and Bands (immature) neutrophils

An increase in Red Blood Cell (RBC) count suggests anemia.

False

The normal reference range for Platelet count is ________ to ________ x 10³/uL.

150 – 400

Which RBC index indicates the "average size" of an RBC?

Mean Corpuscular Volume (MCV)

An increase in _________ indicates folate deficiency

Mean Cell Hemoglobin (MCH)

The normal reference range for Red Cell Distribution Width (RDW) is ________ to ________ %.

11.7 – 15.4%

What is the normal reference range for Prothrombin Time (PT)?

11.0-13.5 sec

The International Normalized Ratio (INR) normal range for a patient not on anticoagulation is 0.8 to 1.2.

True

To calculate the Upper Limit of Normal (ULN) for ESR in men, the formula is ________.

Age / 2

To calculate the Upper Limit of Normal (ULN) for ESR in women, the formula is _______.

(Age + 10) / 2

A ___________ measures, counts, evaluates and studies the aspects of blood; without differential counts the total number of WBCs and with differential differentiates how many of each kind of WBC.

Complete Blood Count (CBC)

A normal ________ measures the amount of hemoglobin (Hgb), hematocrit (HCT), white blood cells (WBC), and platelets (PLT).

Hemogram

The normal WBC count for a CBC is ___________. An increase indicates infection or physiologic stress and a decrease indicates marrow suppression or chemotherapy.

3.4 -10 × 10³ cells/mm3

What is the normal white cell count differential value for neutrophils? What does an increase represent?

45%-73% ; Increase → bacterial infection

What is the normal white cell count differential value for eosinophils? What does an increase represent?

0-4% ; Increase → parasitic infection or hypersensitivity reaction(drug/allergies)

What is the normal white cell count differential value for basophils? What does an increase represent?

0-1% ; Increase → chronic inflammation or leukemia

What is the normal white cell count differential value for lymphocytes? What does an increase or decrease represent?

20-40% ; Increase → Mono, TB, syphilis, viral infections ; Decrease → HIV, radiation, steroids

What is the normal white cell count differential value for monocytes? What does an increase represent?

2-8% ; Increase → in recovery from bacterial infection, leukemia, TB-disseminated infection

What is the normal RBC count for males and females respectively?

4.6-6.2 × 10⁶ cells/mm3 ; 4.2-5.2 × 10⁶ cells/mm3

What do changes in RBC values indicate?

Increase → dehydration, erythrocytosis, polycythemia ; Decrease → anemia

What is the CBC value for hemoglobin in males and females respectively? What do changes indicate?

Male: 14-18 g/dL, Female: 12-16 g/dL ; Increase → hemoconcentration, polycethemia; Decrease → anemia

What is the CBC value for hematocrit in males and females respectively? What do low and high values indicate?

Males - 39-49%, Female - 35-45% ; Low → anemic or acute heavy bleeding; High → thick, sludgy blood

What indices describe the appearance of red blood cells (RBCs)?

MCV, MCH, MCHC, RDW

What does the Mean Corpuscular Volume (MCV) test indicate?

Expresses the volume of an “average” single RBC; normocytic (80-100fL), microcytic (<80 fL), macrocytic (>100fL)

Why would RBC be macrocytic or microcytic?

Macrocytic → B12 or folate deficiency; Microcytic → iron deficiency

What is a reticulocyte count test used to measure?

An indirect measure of RBC production; increase during RBC production

What is a normal CBC platelet count value? what do high and low values indicate?

140,000 - 440,000 per microL ; Low → Thrombocytopenia; High → Thrombocytosis (potential CVA, MI, thrombophlebitis)

What blood chemistry lab includes electrolytes (CO₂, Cl^-, K⁺, Na⁺), 2 kidney function tests (Creatinine and BUN), and glucose?

Chem 7/BMP (Fishbone)

What blood chemistry lab includes glucose, calcium, electrolytes, albumin, total protein, alkaline phosphatase, alanine transaminase, aspartate transaminase, bilirubin, blood urea nitrogen, and creatinine?

Comprehensive Metabolic Panel (CMP) /Chem 12/14

What normal values are found on the serum electrolyte panel?

• Na⁺ - 136 - 145 mEq/L

• K⁺ - 3.5 - 5.0 mEq/L

• HCO₃^- - 24 - 30 mEq/L

• Cl^- - 96-106 mEq/L

What do extreme values of sodium indicate?

• Greater than 145 mEq/L → Hypernatremia - occurs in renal or GI loss, impaired thirst

• Less than 136 mEq/L → Hyponatremia - occurs in CHF, diarrhea, sweating, thiazides

What do extreme values of potassium indicate?

• less than 3.5 mEq/L → Hypokalemia - indicates true or apparent depletion

• greater than 5.0 mEq/L → Hyperkalemia - Indicates true or apparent excess

(Panic >6 → Cardiac arrest)

What do extreme values of Carbon dioxide or Bicarbonate indicate?

• Decreased → Acidosis

• Increased → Alkalosis

What do extreme values of chloride indicate?

• Reduced → metabolic alkalosis

• Increased → metabolic or respiratory acidosis

________ is an indicator of kidney function, with normal values being 0.7-1.5 mg/dL for adults and 0.2-0.7 mg/dL for children.

Serum Creatinine (SCr)

What does an increase in SCr indicate?

Worsening renal function that can lead to hyperprexia, hyperthyroidism, renal dysfunction, dehydration.

_____________ is an indicator of kidney function that may be a reflection of GFR, important in renal function, may be used to assess or monitor hydrational status, protein tolerance and catabolism.

Blood Urea Nitrogen (BUN)

What is a normal Blood Urea Nitrogen (BUN) value and what do changes indicate?

8-20 mg/dL ; Increased → leads to decreased renal perfusion, acute renal failure, obstruction; Decreased → leads to malnutrition, profound liver disease

(Panic > 100 mg/dL)

The _________ relationship has a normal ratio of 10:1, as BUN by itself is not as clinically significant. Greater than 20:1 pre-renal causes of dysfunction, 10:1 - 20:1 intrinsic renal damage, but 20:1 may be normal if both are in normal ranges.

BUN/SCr

What are the normal blood chemistry glucose values and what do changes indicate?

70-110 mg/dL ; Hyperglycemia → 3Ps, may progress to coma ; Hypoglycemia → caused by fasting, insulin administration

What are the normal blood chemistry calcium values and what do changes indicate?

8.5 - 10.8 mg/dL; Less than 8.5 mg/dL → Hypocalcemia and more than 10.8 mg/dL → Hypercalcemia

What are the normal blood chemistry total protein and albumin values and what do changes indicate?

5.5-9.0 g/dL, 3.0-5.0 g/dL ; Low could be caused by liver dysfunction

What are the normal blood chemistry alkaline phosphatase values and what do changes indicate?

Ranges vary widely; Increase → occurs in liver dysfunction

What are the normal blood chemistry aminotransferases (ALT, AST) values and what do changes indicate?

3-30 IU/L, 8-42 IU/L ; Increase AST occurs after MI, muscle diseases, hemolysis.

(Ratio of AST:ALT of 2:1 → suggests Alcoholic Liver Disease (ALD))

___________ are measure indicators of liver disease, sensitive to hepatic inflammation and necrosis.

Aminotransferases

What are the normal blood chemistry bilirubin (direct, conjugated) values and what do changes indicate?

0.1 -0.3 mg/d ; Increase associated with increases in other liver enzymes, reflect liver disease

What are the normal blood chemistry lactate dehydrogenase values and what do changes indicate?

100 - 225 IU/L ; Increase caused by hemolysis, Gilberts syndrome, Crigler-Najar syndrome, or neonatal jaundice

What are the normal blood chemistry magnesium values and what do changes indicate?

1.5 - 2.2 mEq/L; Less Than 1.5 mEq/L → Hypomagnesemia; Greater Than 2.2 mEq/L → Hypermagnesemia

(primarily eliminated by the kidney)

What are the normal blood chemistry phosphate values and what do changes indicate?

2.6 - 4.5 mg/dl; Less than 2.6 → Hypophosphatemia; Greater than 4.5 → Hyperphosphatemia

What do various urine test results indicate?

• Clear yellow - normal

• Cloudy - caused by urates (acid), phosphates (alkaline), RBC/WBC

• Foam - caused by protein/bile acids

______ refers to a test’s ability to designate an individual with a disease as positive. High percentage means few false negatives.

Sensitivity (SnNOut)

_________ of a test is its ability to designate an individual who does not have a disease as negative. Higher percentage will show patients without a finding having no disease.

Specificity (SpPIn)

__________ interpret imaging, perform image-guided procedures, effectively communicate the interpretation, and ensure patient safety.

Radiologist

_________ involves synthesizing image findings with clinical history to formulate the best conclusion.

Image interpretation

What are some examples of image guided procedures?

• Biopsies

• Thoracentesis, Paracentesis, Lumbar puncture

• Drain placement

• Vascular intervention

• Oncology

What are the safety precautions for MRI?

No metal

What are the safety precautions for Interventional radiology?

• Time-out

• Limit risks by blood thinners, NPO, allergies, sterile equipment

• Follow for complication

What is the active ingredient in CT contrast?

Iodinated

What is the active ingredient in MRI contrast?

Gadolinium

What is the active ingredient in Enteric contrast?

Barium, Gastrograffin, etc.

How can contrast be administered?

• By mouth (PO) or by rctm (PR)

• Intravenously (IV), arteially (IA)

• Retrograde urethrally

• Instilled by catheter

• Percutaneously into cavities

_________ allergy is not a contraindication to CT contrast.

Shellfish

What are some mild adverse reactions to contrast?

• Urticaria

• Nausea/vomiting

What are some moderate to severe adverse reactions to contrast?

• Vasovagal

• Bronchospasm

• Anaphylactoid

____________ can occur with iodinated IV (CT) contrast and is defined as a serum creatinine increase of 25%.

Contrast nephrotoxicity

_______________ is a risk of MRI contrast that is an extremely debilitating fibrotic condition of the skin and solid organs, rare.

Nephrogenic Systemic Fibrosis (NSF)

_________ contrast has been shown to cross the human placenta and ________ is thought to cross the placenta.

Iodinated, Gadolinium

List imaging tests in terms of lowest to highest radiation exposure.

Ultrasound → MRI → X-Rays → CT → Nuclear medicine

What are the special patient populations to consider in radiology?

Pregnant, Children, Renal Insufficiency

When is the use of contrast in CT most helpful?

• Abdomen - evaluating for most primaries, especially renal, pancreas, liver

• Brain - metastatic tumors

• Angiogram of the head and neck

• Characterizing an aortic aneurysm

_______________ is the best resource for determining best imaging to order for various situations.

American College of Radiology (ACR) Appropriateness Criteria

What can be visualized in the PA view of a plain field X-Ray?

• Scapula is seen in the periphery of the thorax

• Clavicles project over lung fields

• Posterior ribs are distinct

• Position of markers

What can be visualized in the AP view of a plain field X-Ray?

• Scapula over lung fields

• Clavicles are above the apex of lung fields

• Anterior ribs are distinct

• Position of markers

___________ refer to bone because they absorb the greatest amount of x-ray; bone is white on radiographs.

Radiodense / Radiopaque

_________ refers to air because it absorbs little to no x-ray; air is black on x-ray.

Radiolucent

What are the 5 basic densities of X-Ray?

• air

• fat

• fluid or soft tissue

• calcium

• metal

__________ refers to white structure on an MRI image.

Bright signal

__________ refers to dark gray to black on an MRI image.

Dark signal

Signal intensity of MRI is dependent on …

• Tissue content of H20

• Sequence (T1 or T2)

_______________ involves the injection of radiopharmeceutical that is scanned with radiation sensitive detectors, that reconstruct images from levels of radiation received.

Nuclear medicine, SPECT, PET

_____ shows anatomy and location of RA in space, ________ show function.

CT; SPECT & PET

__________ refers to light gray to medium gray signal return on an ultrasound.

Isoechoic

_________ refers to very bright, heavy signal return on an ultrasound.

Hyperechoic/Echogenic (sonodense)

_________ refers to dark, without echo return on an ultrasound.

Anechoic (sonolucent)

_________ refers to the visual recognition of figures and whole forms, not a collection of simple lines and curves.

“Gestalt”

________ refers to something that one has seen before and is instantly recognizeable.

“Aunt Minnie”

What is the systematic approach to chest X-rays?

• A: airways

• B: breathing (lungs and pleural spaces)

• C: circulation (cardiomediastinal contour)

• D: disability (bones- especially fractures)

• E: everything else

What is the systematic approach to abdominal X-rays?

• A: air (where should it be)

• B: bowel (postion, size, wall thickness)

• D: dense structures (calcification and bones)

• O: organs and soft tissues

• X: external objects and artifacts

_________ refers to bones that are brittle and fracture.

Osteoporosis

________ refers to bones that are soft and bend.

Osteomalacia