Hey guys, we're here going to talk about some labs. For this first section, some routine lab work we're going to go over. So many of you have probably had labs drawn at some point or another.
Why do people have labs drawn? They may want to find some causes of some symptoms such as fatigue, weight loss, weakness, fever, or bruising. If the person has had bleeding, how much blood loss has occurred. I may do DNA testing, maybe we'll be trying to diagnose some blood disorders such as anemia or leukemia, maybe pre-surgery screening, and maybe monitoring the body's response to certain treatments or medications.
So here is if you've had your labs drawn this setup will look familiar to you. Tourniquet applied, area disinfected, needle introduced into the vein, then they draw the blood and then analyze the blood. in the lab. So CBC is one of a basic lab that's done frequently ordered. It consists of white blood cell, red blood cell, hemoglobin, hematocrit, red blood cell indices, which describe the size and hemoglobin content of the red blood cell, and platelets.
A CBC with differential gives you a more thorough breakdown of the white blood cell. CBC is one of the most frequently ordered blood tests. It doesn't require any major prep or fasting, and it can tell us lots of information about our patient.
Some values will vary from male to female because they're based on body mass, and men often will have greater body mass than females. Some medications and substances can alter results, so get a good thorough medication history on your patient. Components of a CBC, you've got your white blood cells or leukocytes.
These fight infection, and their normal range is 5,000 to 10,000. Red blood cells, RBC or erythrocytes, transport oxygen and carbon dioxide. They live about 100 to 120 days.
Hematocrit or HCT measures red blood cell mass. Hemoglobin transports... oxygen and CO2.
Flatelets or thrombocytes are necessary for clotting and control of bleeding. Your red blood cell breakdown here, red blood cell indices are used to determine the type of anemia if there is a deficit present. So MCV is mean corpuscular volume which is the size of the cell. MCHC is mean corpuscular hemoglobin concentration, which is the concentration of hemoglobin in the cell, and MCH is mean corpuscular hemoglobin, which is the weight of hemoglobin in the cell.
Your RDW or red blood cell distribution width shows the degree of variability in abnormal cell size. Mean platelet volume is an index of platelet production. So all that information is in a basic CBC. So factors can be off based on different disease processes, blood thinners, dehydration.
These are important to know and be aware that male and female may differ some of the ranges and also pediatric patient ranges may differ as well. You can check that out in your Fischbach lab book. but we'll talk further about like what they mean and what it means if something is high or low so your differential or your breakdown of your white blood cells gives us a lot of information about our patient white blood cells are further broken down into two categories which are granulocytes which consist of neutrophils basophils and eosinophils and a granulocytes which are lymphocytes and monocytes granulocytes are named this because under a microscope they have distinctive granules in the cytoplasm.
White blood cells live 13 to 20 days and are excreted in your stool. Their range is 5,000 to 10,000. What white blood cells do is defend our body by something called phagocytosis and what this is is the white blood cell encapsulates a foreign body and destroys it.
So a bacteria or something that's invaded the body and they are our infection fighter. Elevated white blood cell count or leukocytosis would indicate an infectious process or an injury, response to an injury. A decreased white blood cell count, also known as leukopenia, indicates that something is compromised with our immune system response or may indicate bone marrow depression. So white blood cell count is increased in injury or infectious process, decreased in some sort of abnormality with the immune response.
Neutrophils, which are the largest component of white blood cells and are considered the primary defense. If you have too few of these, you have something called neutropenia, often seen in cases of maybe cancer patients or chemotherapy patients. If your primary defense mechanism is suppressed in neutropenia, then the person's at a great risk for infection because they don't have those cells to come to the defense of the body.
Eosinophils, these respond to allergic and parasitic disease processes. contain histamine. Basophils are in cases of chronic inflammation.
We check those out if there's someone having a chronic inflammation process. Lymphocytes migrate to areas of infection and are seen in a viral response, respond to viruses. Monocytes remove injured and dead cells. They're considered second line of defense against infection.
So here we have... So the big five or the major ones that you need to know, red blood cells, hemoglobin, hematocrit, platelet, and white blood cell count. Red blood cells transport oxygen and carbon dioxide. They're a flexible cell that allows it to travel through the smallest capillaries.
Decreased values are associated with anemia and affect every body system. If the body systems are not getting the oxygen that they need, they're not going to function correctly. Increased values of RBCs associated with overproduction of RBCs, high altitudes, tobacco use, dehydration, or certain diseases, renal, pulmonary, or cardiovascular generally. Your hemoglobin gives blood its red color. It's the vehicle for oxygen and carbon dioxide transport.
Normal range 12 to 16 in females, 14 to 17 in males. It's decreased in anemia. hemorrhage or excessive bleeding over dilution and it's increased in dehydration in some diseases so if the blood is overly diluted or they're having excessive bleeding or they're anemic the hemoglobin can be low if the person is dehydrated and their blood is more concentrated they may have an increase of hemoglobin So hematocrit, what that does is measure percentage of red blood cells compared with total blood volume.
So it's a percentage rather than just a numerical value. It's 42 to 52 percent in males and 36 to 48 percent in females. It's measured or obtained by spinning the blood to separate red blood cells and plasma. Platelets, these are what's responsible for clotting the blood.
So if we don't have enough. clotting mechanism, or if our platelets are low, then we're going to be at risk for excessive bleeding. 140,000 to 400,000 is the normal range for platelets.
And your white blood cells is your body's defense mechanism. 5,000 to 10,000 is normal range, and it's elevated in infection, inflammation, tissue injury. An electrolyte panel, often ordered as part of a routine physical. measures our main electrolytes in our body, sodium, potassium, chloride, bicarb.
A person's diet provides sodium, potassium, and chloride, and the kidneys excrete them. So there's a balance in between the excretion from the kidneys and the person's intake. The lungs provide oxygen and regulate CO2, which is in balance with bicarb, bicarbonate.
The balance of these chemicals is an indication of the well-being of basic body function. So your body is always trying to maintain homeostasis or balance if something's off in one of these mechanisms or one of these functions especially performed by the kidneys and heart then you're going to have imbalances in your electrolytes so your comprehensive metabolic panel takes it a little bit further than an electrolyte panel electrolyte panel would examine sodium potassium chloride and bicarbonate A basic metabolic panel would take it a step further and add in creatinine, glucose, BUN, and calcium. And a comprehensive metabolic panel would also have all those previously mentioned, plus albumin, alkaline phosphatase, ALT, AST, total bilirubin, and total protein.
This requires the patient to be fasting because they are affected by dietary intake. So the patient will need to fast 10 to 12 hours before having the test done. they'll tell them not to eat anything after midnight. So glucose, fasting blood sugar normal is less than 100 millig...well less than 100. If a fasting blood sugar greater than 126 is obtained on two separate occasions, it's indicative of a diabetes process, or if it's greater than 200 randomly, it's indicative of diabetes. Your calcium normal level is 8.8 to 10.4.
Calcium is stored in bones and teeth. This test measures total and ionized calcium in the blood. So calcium if it's too low less than 4.4 you can get tetany and seizures.
So tetany is like involuntary muscle contractions, involuntary nerve actions. And then if it's too high, greater than 13, you can get cardiac dysrhythmias, coma, and cardiotoxicity. Calcium is affected by protein in the blood, so calcium binds to protein.
So those levels will rise and fall following your protein and your albumin. Albumin is used to elevate the blood sugar levels. is used to evaluate nutritional status 3.5 to 5.2 is normal range in liver and renal disease albumin can be lost and an acute illness as well total protein is the total protein in the blood six to eight point three is normal range of components further components of your cmp um Sodium, 136 to 145 is normal.
Sodium is a huge electrolyte to be aware of. It affects the other electrolytes, acid-base balance, water balance, water intoxication, dehydration. Lower levels can cause weakness, dehydration, neurologic symptoms, and vascular problems.
Too high of levels can cause cardiovascular and renal symptoms. So you'll learn more about sodium as you go along, but just know that sodium is a major one to be aware of. Potassium is important in nerve conduction, muscle function, acid-base balance, and osmotic pressure.
Along with calcium and magnesium, potassium controls the rate and force of heart contraction and cardiac output. So if you're potassium, you have potassium. Deficits that can actually be fatal, you'll see changes on the EKG or the activity of the heart with both elevated and decreased potassium levels. So that's one to keep a close eye on because it can affect cardiac function.
Carbon dioxide should be 23 to 30. What this test measures is either the alkalinity or acidity of venous, arterial, and capillary blood. Chloride 96 to 106 is the normal range. Chloride is looked at as part of a big picture.
It's helpful in diagnosing acid-based disorders and water balance. BUN or blood urea nitrogen 6 to 20. This one is a little bit more you can think hydration with this one. So if the person is over hydrated due to IV fluids or an endocrine disorder the BUN will decrease or fall or be low if they are dehydrated in which the plasma volume decreases that concentration of urea is going to increase and the kidneys retain sodium and water which makes the BUN higher so it measures the nitrogen portion of urea. In the blood, elevated BUN is seen in renal disease, urinary tract obstruction, diabetes with ketoacidosis, burn in cancer patients, steroid use.
Decreased BUN can be seen in liver failure, malnutrition, and some endocrine diseases. So if in the case, for instance, for liver disease, liver synthesizes urea. So if the liver isn't operating at its normal capacity, the BUN can be decreased.
Creatinine. Creatinine is more specific than BUN to kidney function. It's a more specific indicator of kidney function.
It can vary with gender, as you see, 0.9 to 1.3 for males, 0.6 to 1.1 for females. It's more sensitive and specific indicator of kidney disease than the BUN. Kidney disease reduces excretion of creatinine.
So if the kidneys are not functioning like they should, they are not excreting creatinine. What creatinine is, it is a waste product of muscle metabolism. So if the kidneys are not filtering like they should and excreting that creatinine, then the creatinine goes up. If you have increased creatinine, which indicates the kidneys aren't functioning correctly. Men have a higher creatinine range than women because creatinine is a waste product of muscle metabolism and they have generally more muscle mass.
So that is a little bit about creatinine and your CMP. So that concludes our part 1a of our lab lecture. So that's our CMP and CBC. for this one and you can always refer to your lab handbook as well to get some more information. And that concludes this first lecture on the labs.
Thank you.