Rational Approach to the Use of Labs and Imaging

Question 1

purulent

Answer 1

consisting of, containing, or discharging pus

Question 2

CBC

Answer 2

Complete Blood Count: White Blood Count (WBC), Hemoglobin (Hb) and Hematocrit (HCT)

Question 3

Hemoglobin

Answer 3

The hemoglobin molecule fills up the red blood cells. It carries oxygen and gives the blood cell its red color. The hemoglobin test measures the amount of hemoglobin in blood and is a good measure of the blood’s ability to carry oxygen throughout the body.

Question 4

Hematocrit

Answer 4

This test measures the amount of space (volume) red blood cells take up in the blood. The value is given as a percentage of red blood cells in a volume of blood. For example, a hematocrit of 38 means that 38% of the blood’s volume is made of red blood cells. Hematocrit and hemoglobin values are the two major tests that show if anemia or polycythemia is present.

Question 5

WBC

Answer 5

White blood cells protect the body against infection. If an infection develops, white blood cells attack and destroy the bacteria, virus, or other organism causing it. White blood cells are bigger than red blood cells but fewer in number. When a person has a bacterial infection, the number of white cells rises very quickly. The number of white blood cells is sometimes used to find an infection or to see how the body is dealing with cancer treatment.

Question 6

WBC, differential

Answer 6

The major types of white blood cells are neutrophils , lymphocytes, monocytes, eosinophils, and basophils. Immature neutrophils, called band neutrophils, are also part of this test. Each type of cell plays a different role in protecting the body. The numbers of each one of these types of white blood cells give important information about the immune system . Too many or too few of the different types of white blood cells can help find an infection, an allergic or toxic reaction to medicines or chemicals, and many conditions, such as leukemia .

Question 7

RBC

Answer 7

Red blood cells carry oxygen from the lungs to the rest of the body. They also carry carbon dioxide back to the lungs so it can be exhaled. If the RBC count is low (anemia), the body may not be getting the oxygen it needs. If the count is too high (a condition called polycythemia), there is a chance that the red blood cells will clump together and block tiny blood vessels (capillaries). This also makes it hard for your red blood cells to carry oxygen.

Question 8

RBC indices

Answer 8

There are three red blood cell indices: mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). They are measured by a machine, and their values come from other measurements in a CBC. The MCV shows the size of the red blood cells. The MCH value is the amount of hemoglobin in an average red blood cell. The MCHC measures the concentration of hemoglobin in an average red blood cell. These numbers help in the diagnosis of different types of anemia. Red cell distribution width (RDW) can also be measured which shows if the cells are all the same or different sizes or shapes.

Question 9

Platelets

Answer 9

There are three red blood cell indices: mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). They are measured by a machine, and their values come from other measurements in a CBC. The MCV shows the size of the red blood cells. The MCH value is the amount of hemoglobin in an average red blood cell. The MCHC measures the concentration of hemoglobin in an average red blood cell. These numbers help in the diagnosis of different types of anemia. Red cell distribution width (RDW) can also be measured which shows if the cells are all the same or different sizes or shapes.

Question 10

Mean Platelet Volume (MPV)

Answer 10

Mean platelet volume measures the average amount (volume) of platelets. Mean platelet volume is used along with platelet count to diagnose some diseases. If the platelet count is normal, the mean platelet volume can still be too high or too low.

Question 11

anemia

Answer 11

a condition in which you don’t have enough healthy red blood cells to carry adequate oxygen to the body’s tissues.

Question 12

polycythemia

Answer 12

an abnormally increased concentration of hemoglobin in the blood, through either reduction of plasma volume or increase in red cell numbers. It may be a primary disease of unknown cause, or a secondary condition linked to respiratory or circulatory disorder or cancer.

Question 13

ischemia

Answer 13

a restriction in blood supply to tissues, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems with blood vessels, with resultant damage to or dysfunction of tissue.

Question 14

Na levels

Answer 14

determine the osmolarity of serum (a measure of the different solutes in plasma) and significant alterations can have a profound effect on cerebral function

Question 15

BUN

Answer 15

Blood Urea Nitrogen results from the breakdown products of protein

Question 16

K levels

Answer 16

kept at very narrow range, most K is intracellular and resting membrane potential depends on this tight control, low or high L levels can result in cardiac arrythmias.

Question 17

Cr levels

Answer 17

a measure of muscle mass and breakdown and is cleared by the kidney, very good measure of kidney function although can be affected by muscle mass

Question 18

CO2 levels

Answer 18

a measure of bicarbonate in the serum, patients with lactic acidosis due to septic shock will have decreasing levels of CO2 as the bicarbonate neutralizes the acid produced by anaerobic metabolism

Question 19

Cl levels

Answer 19

inverse relationship with bicarbonate to maintain electrical neutrality (negative anion) in lactic acidosis it will drop due to the presence of lactate

Question 20

lactic acidosis

Answer 20

Lactic acidosis is a form of metabolic acidosis that begins when a person overproduces or underutilizes lactic acid, and their body is not able to adjust to these changes. People with lactic acidosis have problems with their liver (and sometimes their kidneys) being able to remove excess acid from their body.

Question 21

glucose levels

Answer 21

often elevated during infection and stress, hormone release (catecholamines and cortisol) causes antagonism of insulin

Question 22

A1C

Answer 22

glucose measure over 120 days

Question 23

catecholamines

Answer 23

Catecholamines are hormones made by your adrenal glands, which are located on top of your kidneys. Examples include dopamine; norepinephrine; and epinephrine (this used to be called adrenalin or adrenaline). Your adrenal glands send catecholamines into your blood when you’re physically or emotionally stressed.

Question 24

cortisol

Answer 24

Cortisol is a steroid hormone, one of the glucocorticoids, made in the cortex of the adrenal glands and then released into the blood, which transports it all round the body. Almost every cell contains receptors for cortisol and so cortisol can have lots of different actions depending on which sort of cells it is acting upon. These effects include controlling the body’s blood sugar levels and thus regulating metabolism, acting as an anti-inflammatory, influencing memory formation, controlling salt and water balance, influencing blood pressure and helping development of the foetus. In many species cortisol is also responsible for triggering the processes involved in giving birth

Question 25

glucocorticoids

Answer 25

a group of steroid hormones, make by the outer part (cortex) of the adrenal gland, including cortisol, which have anti-inflammatory effects.

Question 26

oncotic pressure

Answer 26

the pressure exerted by plasma proteins on the capillary wall. A form of osmotic pressure exerted by proteins in a fluid that usually tends to pull water into the circulatory system.

Question 27

hydrostatic pressure

Answer 27

Hydrostatic pressure is a force generated by the pressure of fluid on the capillary walls either by the blood plasma or interstitial fluid. A pressure generated by fluid on the walls of the capillary, usually forcing water out of the circulatory system.

Question 28

BMP

Answer 28

Basic Metabolic Panel includesBlood Urea Nitrogen (BUN)
Calcium
Carbon Dioxide (Bicarbonate)
Chloride
Creatinine
Glucose
Potassium
Sodium

Question 29

CMP

Answer 29

Comprehensive Metabolic Panel includes:Albumin
Blood Urea Nitrogen (BUN)
Calcium
Carbon Dioxide (Bicarbonate)
Chloride
Creatinine
Glucose
Potassium
Sodium
Total Bilirubin
Total Protein
Alanine Aminotransferase (ALT)
Alkaline Phosphatase (ALP)
Aspartate Aminotransferase (AST)

Question 30

troponin

Answer 30

A troponin test measures the levels of troponin T or troponin I proteins in the blood. These proteins are released when the heart muscle has been damaged, such as occurs with a heart attack. The more damage there is to the heart, the greater the amount of troponin T and I there will be in the blood.

Question 31

D dimer

Answer 31

D-dimer is one of the protein fragments produced when a blood clot gets dissolved in the body. It is normally undetectable or detectable at a very low level unless the body is forming and breaking down blood clots. Then, its level in the blood can significantly rise. This test detects D-dimer in the blood.

Question 32

BNP

Answer 32

Brain natriuretic peptide (BNP) test is a blood test that measures levels of a protein called BPN that is made by your heart and blood vessels. BNP levels are higher than normal when you have heart failure.

Question 33

ALT

Answer 33

Alanine aminotransferase (ALT) is an enzyme found mostly in the cells of the liver and kidney. Much smaller amounts of it are also found in the heart and muscles. This test measures the level of ALT in the blood.

The function of ALT is to convert alanine, an amino acid found in proteins, into pyruvate, an important intermediate in cellular energy production. In healthy individuals, ALT levels in the blood are low. When the liver is damaged, ALT is released into the blood, usually before more obvious signs of liver damage occur, such as jaundice. This makes ALT a useful test for early detection of liver damage.

The liver is a vital organ located in the upper right-hand side of the abdominal area, just beneath the rib cage. It is involved in many important functions in the body. The liver helps to process the body’s nutrients, manufactures bile to help digest fats, produces many important proteins such as blood clotting factors and albumin, and breaks down potentially toxic substances into harmless ones that the body can use or eliminate.

A number of conditions can cause damage to liver cells, resulting in an increase in ALT. The test is most useful in detecting damage due to hepatitis or as a result of drugs or other substances that are toxic to the liver.

ALT is commonly tested in conjunction with aspartate aminotransferase (AST), another liver enzyme, as part of a liver panel. Both ALT and AST levels usually rise whenever the liver is being damaged, although ALT is more specific for the liver and, in some cases, may be the only one of the two to be increased. An AST/ALT ratio may be calculated to aid in distinguishing between different causes and severity of liver injury and to help distinguish liver injury from damage to heart or muscles.

Question 34

ALP

Answer 34

Alkaline phosphatase (ALP) is an enzyme found in several tissues throughout the body. The highest concentrations of ALP are present in the cells that comprise bone and the liver. Elevated levels of ALP in the blood are most commonly caused by liver disease or bone disorders. This test measures the level of ALP in the blood.

In the liver, ALP is found on the edges of cells that join to form bile ducts, tiny tubes that drain bile from the liver to the bowels, where it is needed to help digest fat in the diet. ALP in bone is produced by special cells called osteoblasts that are involved in the formation of bone. Each of the various tissue types produces distinct forms of ALP called isoenzymes.

ALP blood levels can be greatly increased, for example, in cases where one or more bile ducts are blocked. This can occur as a result of inflammation of the gallbladder (cholecystitis) or gallstones. Smaller increases of blood ALP are seen in liver cancer and cirrhosis, with use of drugs toxic to the liver, and in hepatitis.

Any condition causing excessive bone formation, including bone disorders such as Paget’s disease, can cause increased ALP levels. Children and adolescents typically have higher blood ALP levels because their bones are still growing. As a result, the ALP test must be interpreted with different reference (normal) values for children and for adults.

It is possible to distinguish between the different forms (isoenzymes) of ALP produced by different types of tissues in the body. If it is not apparent from clinical signs and symptoms whether the source of a high ALP test result is from liver or bone disease, then a test may be performed to determine which isoenzyme is increased in the blood.

Question 35

AST

Answer 35

Aspartate aminotransferase (AST) is an enzyme found in cells throughout the body but mostly in the heart and liver and, to a lesser extent, in the kidneys and muscles. In healthy individuals, levels of AST in the blood are low. When liver or muscle cells are injured, they release AST into the blood. This makes AST a useful test for detecting or monitoring liver damage.

The liver is a vital organ located in the upper right-hand side of the abdominal area just beneath the rib cage. It is involved in many important functions in the body. The liver helps to process the body’s nutrients, manufactures bile to help digest fats, produces many important proteins such as blood clotting factors, and breaks down potentially toxic substances into harmless ones that the body can use or excrete.

A number of conditions can cause injury to liver cells and may cause increases in AST. The test is most useful in detecting liver damage due to hepatitis, drugs toxic to the liver, cirrhosis, or alcoholism. AST, however, is not specific for the liver and may be increased in conditions affecting other parts of the body.

An AST test is often performed along with an alanine aminotransferase (ALT) test. Both are enzymes found in the liver that become elevated in the blood when the liver is damaged. A calculated AST/ALT ratio is useful for differentiating between different causes of liver injury and in recognizing when the increased levels may be coming from another source, such as heart or muscle injury.

Question 36

hyperchromic

Answer 36

Having a higher than normal amount of hemoglobin in the red blood cells.

Question 37

hypochromic

Answer 37

red blood cells have less color than normal when examined under a microscope. This usually occurs when there is not enough of the pigment that carries oxygen (hemoglobin) in the red blood cells.

Question 38

microcytic

Answer 38

small red blood cells

Question 39

macrocytic

Answer 39

large red blood cells