Labs Flashcards by Daniel Guck

Generally, when should you order lab tests?

When it will possibly change the treatment or clinical outcome

(for a reason)

How well did you know this?

Not at all

Perfectly

What 2 organ systems would it be considered “too late” when the physical exam reveals an abnormality?

Liver and Kidney

How well did you know this?

Not at all

Perfectly

What time should you put on a lab order if you want the results right away?

STAT (always in ER/ICU)

How well did you know this?

Not at all

Perfectly

What time should you put on a lab order if you want the results by next shift?

No time

How well did you know this?

Not at all

Perfectly

What time should you put on a lab order if you want the results at a specific time?

State the exact time

How well did you know this?

Not at all

Perfectly

True or False: when writing a lab order, “now” is mutually acceptable as “STAT”

False

“now” should never be written

How well did you know this?

Not at all

Perfectly

Which lab consists of the following items?

WBC, RBC, Hb, Platelets, Differential on WBCs, Indices, and Hct

CBC

How well did you know this?

Not at all

Perfectly

This is a listing of the absolute and the percentage of the specific types of WBCs

Differential

How well did you know this?

Not at all

Perfectly

What 2 main reasons should you order a CBC?

Detecting Disease

Monitoring disease

How well did you know this?

Not at all

Perfectly

What are the 6 WBC types that are found on the differential for a CBC?

Neutrophils

Lymphocytes

Monocytes

Eosinophils

Basophils

Bands (immature WBCs)

How well did you know this?

Not at all

Perfectly

What are “segs”?

Neutrophils (their nucleus is segmented)

How well did you know this?

Not at all

Perfectly

What is a “left shift”?

The trend towards less mature WBC’s or towards an increase in neutrophils.

How well did you know this?

Not at all

Perfectly

What would infection, inflammation, anoxia, drugs, or stress/pain do to WBC production?

↑ production and release of immature cells

How well did you know this?

Not at all

Perfectly

What are thee 6 etiologies for neutrophilia?

Metabolic disorders

Acute infection

Drugs/toxins

Hematological disorders

Acute inflammation

Tissue necrosis

(MAD HAT)

How well did you know this?

Not at all

Perfectly

Viral infections, some bacterial infections, chronic inflammatory disorders, and blood diseases will raise which WBC?

Lymphocytes

How well did you know this?

Not at all

Perfectly

Bacterial infections, viral infections, hematological disorders, and collagen vascular disease will raise which WBC?

Monocytes

How well did you know this?

Not at all

Perfectly

Parasitic diseases, allergic disease, skin disorders, and malignancies will raise which WBC?

Eosinophils

How well did you know this?

Not at all

Perfectly

Define the following acronyms:

MCHC MCV MCH RDW

MCHC- mean corpuscular hemoglobin concentration

MCV- mean corpuscular volume

MCH- mean corpuscular Hb

RDW- RBC distribution width

How well did you know this?

Not at all

Perfectly

What are the 3 broad topics that describe a decrease in RBC count?

Microcytic hypochromic anemia

Normocytic normochromic anemia

Macrocytic anemia

How well did you know this?

Not at all

Perfectly

What are the 2 broad topics that increase the RBC count?

Polycythemia vera (PV)

Secondary polycythemia

How well did you know this?

Not at all

Perfectly

What will a B12 or folate deficiency do to MCV?

increase it

How well did you know this?

Not at all

Perfectly

What are the 2 main conditions that cause a ↓ MCV?

Iron deficiency anemia

Hemolytic anemia

How well did you know this?

Not at all

Perfectly

Infections or myeloproliferative disorders will cause what change in platelet count?

↑ platelets

How well did you know this?

Not at all

Perfectly

What 2 general things can cause a decreased platelet count?

↓ production (marrow depression)

↑ destruction (autoimmune)

How well did you know this?

Not at all

Perfectly

What will toxins and drugs do to reticulocyte count?

↓ reticulocytes

What 2 things will ↑ reticulocyte count?

Hemolytic anemia Acute blood loss

What will anemia, blood loss, fluid retention, or edematous states (CHF) do to [Hb]?

↓ Hb

If a patient has blood loss, anemia, or state or hydration, what measurement can you use to evaluate it?

Hct

Generally, which lab test screens for Renal + Electrolytes?

BMP

What does a BUN:Cr \> 20 indicate?

Prerenal azotemia (Dehydration causes ↑ BUN reabsorption, which ↑ this ratio)

What does a BUN:Cr from 10-15 indicate?

Renal state (normal)

What does a BUN:Cr \<20 indicate?

Postrenal azotemia (Obstruction ↓ BUN reabsorption, which ↓ this ratio)

What is the difference between azotemia and uremia?

Azotemia- ↑ BUN and Cr in blood (lab Dx) Uremia- ↑ urine in blood, refers to end-stage kidney disease/renal failure. (all uremic pts are azotemic, but not all azotemic pts are uremic)

What is the formula to determine creatinine clearance when only the serum creatinine is known? Males and Females

Male: (Kg)\*(140-age)/72\*(serum Cr) Female: (Kg)\*(140-age)\*(0.85)/72\*(serum Cr)

What is the main reason to order a serum Cr level?

Assess GFR (renal fxn)

What is a common cause of hypercalcemia based on elevated PTH?

Primary hyperparathyroidism with an adenoma

What is the most common cause of hypocalcemia?

Hypoalbuminemia

What is the eqn to adjust serum Ca under a depressed albumin?

Adjusted Ca = (serum Ca) - (serum albumin) + 4.0

What metabolic state causes decreased CO2?

Metabolic acidosis

Respiratory alkalosis, renal disease (pyelonephritis), severe dehydration, and DI can cause an increase in which ion?

Cl-

What 3 things can cause a loss of Cl-?

Renal loss (loop diuretics) GI loss Metabolic alkalosis (vomiting HCl)

Diabetes, Acute pancreatitis, endocrine dysfxn, and drugs can cause what change in [glucose] in the blood?

Hyperglycemia

What mg/dl of fasting blood sugar do you need to be diagnosed with diabetes mellitus?

\> 126 mg/dl

What mg/dl of random blood sugar do you need to be diagnosed with diabetes mellitus?

\> 200 mg/dl

This is the test for diabetes that uses a specific glucose pill that is given every 30 minutes and recorded as a curve. (not done anymore)

Glucose tolerance test

What are the 4 times in the day that you should check blood sugars with a home glucometer?

6am 11am 4pm 9pm

What is the most important electrolyte to measure?

K+

What 4 things can cause hypokalemia?

GI loss (vomiting, diarrhea) Move to intracellular (alkalosis, insulin) Urine loss (diuretics) Decreased intake

What are the 3 reasons to have hyperkalemia?

Renal failure IV therapy Thrombocytosis/leukocytosis

What are the 2 reasons to cause isotonic hyponatremia?

Hyperproteinemia Hyperlipidemia

What are the 2 reasons to cause hypertonic hyponatremia?

Hyperglycemia Medication

What are the 2 reasons to cause hypotonic hyponatremia?

Renal loss with diuretics Edema with CHF

What is added to the BMP to make a CMP?

Liver markers

This is the test that is a nonspecific indicator of illness over time, where albumin decreases and alpha2globulin increases.

A/G ratio

This is quantitively the most significant protein synthesized by the liver.

Albumin

What can subacute and chronic debilitating diseases, liver disease, malabsorption, and malnutrition do to albumin levels?

↓ albumin

What 4 liver conditions can lead to an elevated serum Alkaline Phosphatase (AP)?

Cholestasis CHF Obstructive and Hepatocellular processes

What 2 bone conditions can lead to an elevated serum Alkaline Phosphatase (AP)?

Metastatic malignancy Hyperthyroidism

What can a late MI or pregnancy do to AP levels?

↑ them

What does ALT and AST stand for?

ALT- alanine aminotransferase AST- aspartate aminotransferase

What can liver disease, CHF, infectious mononucleosis, and acute pancreatitis do to aminotransferase levels?

↑ aminotransferases

Antibiotics, antiepileptics, statins, NSAIDS, sulfonylureas, substances of abuse, and herbs may increase what "enzymes" in the blood?

Liver enzymes

What is the 1 condition in each of the following areas that may increase AST? Liver Heart Skeletal muscle RBC's

Liver- Hepatitis Heart- acute MI Skeletal muscle- Trauma RBC's- Hemolytic anemia

Liver disease, congenital hyperbilirubinemia, hemolytic anemia, and malnutrition may increase levels of what marker in the blood?

Bilirubin

Chronic infection, dehydration, collagen-autoimmune disease, and hemolysis may increase what marker in the blood?

Proteins

What is the most sensitive marker for acute MI and is independent of renal fxn?

Troponin I

What underlying condition may cause troponin T levels to be inaccurate in the diagnosis of an MI?

Renal insufficiency

What is the newest reason to obtain a total CPK level?

Rhabdomyolysis with statins

What 3 areas is LDH-1 distributed?

Heart Erythrocytes Renal Cortex

What 2 conditions can you use LDH-1 to diagnose?

Acute MI Hemolytic anemia

What 2 areas is LDH-3 distributed?

Lung Lymphocytes

LDH-3 is good for determining what conditions?

Acute Pulmonary Infarction (PI?) Lymphocytosis

What 2 areas is LDH-5 distributed?

Liver Skeletal muscle

LDH-5 is good for determining what conditions?

Hepatitis SkM injury

What cardiac serum marker exhibits the following characteristics? Rise- 0.5-2hr Peak- 5-12hr Return to normal- 18-30hr

Myoglobin

What cardiac serum marker exhibits the following characteristics? Rise- 3-8hr Peak- 9-30hr Return to normal- 2-3d

CPK-MB

What cardiac serum marker exhibits the following characteristics? Rise- 3-6hr Peak- 10-24hr Return to normal- 5-15d

Troponin I

What cardiac serum marker exhibits the following characteristics? Rise- 8-18hr Peak- 2-3d Return to normal- 6-10d

LDH-1

Who is recommended to have an LDL level \<160?

Everyone

Who is recommended to have an LDL level \< 130?

Those with \> 1 risk factor

Who is recommended to have an LDL level \< 100?

Those with identified CAD, DM, any atherosclerotic disease, or multiple CAD risk factors

Who is recommended to have an LDL level \< 70?

Those with identified CAD or DM

What is the main reason to get an ESR?

Minor tissue inflmmation

What is the test used to diagnose DM, and estimates the glucose control for the previous 2-3 months?

HbA1c

What is the method to get blood cultures?

2 different sites at 2 different times (15 mins apart)

Out of the 3 following Syphilis tests, which one is confirmatory? RPR VDRL FTA-ABS

FTA-ABS

What condition in each of the following areas causes an increased serum amylase? Pancreas Salivary GI Liver

Pancreas- pancreatitis Salivary- Parotitis GI- Perforated bowel Liver- hepatitis, alcoholism

What marker is superior to total amylase for specificity and sensitivity for acute pancreatitis?

Lipase

Which lab do you use to monitor warfarin (coumadin) effect?

What drug do you monitor with the PTT?

Heparin

What are the 2 commonly ordered thyroid tests?

TSH, free T4

How often should you order cardiac enzymes/markers for an evolving MI?

Q6 hours x 3

How often should you order liver enzymes for a patient on statins?

After 1 month and then q 3-4 months

With treatment, how often will insurance pay for HbA1c checks?

q 3 months

How often should you obtain HIV RBA viral load and CD4 counts?

q 1-3 months

When should you order PSAs?

Yearly at 50 Yearly with family Hx at age 40

The CEA marker is indicative for what cancer?

Colon CA

The CA125 marker is indicative for what cancer?

Ovarian

The AFP marker is indicative for what cancer?

Hepatocellular CA

Review: Which panel includes kindey and electrolytes?

BMP

What is the only liver fxn test?

Albumin

Review: Which panel includes kindey, electrolytes, and liver?

CMP

Review: Which panel includes only liver markers?

Hepatic Function Panel

Review: Which panel includes CO2, Cl-, K, and Na?

Electrolyte panel

What does this stick diagram measure?

BMP

Fill in this stick diagram

What does this stick diagram measure?

BMP

Fill in this stick diagram

What does this stick diagram measure?

CBC

Fill in the stick diagram