Mean Corpuscular Volume (MCV) and Hemoglobin (MCH) (Nursing)

00:01 Now, let's look at some of these other ones.

00:03 MCV means mean corpuscular volume.

00:06 That's the average volume of the red blood cell.

00:09 This is really what I want you to look at.

00:11 Just know what MCV is, that it's the mean corpuscular volume, and that's what it tells us -- the average volume of the red blood cells.

00:19 I've put the formula up there for you, but don't memorize that.

00:22 That's not worth the real estate in your brain, but that is how it's calculated.

00:25 You take the hematocrit, divide it by the red blood cells, and that will give you the average volume of the red blood cells.

00:32 So we know that the mean corpuscular volume tells us the average volume of the red blood cells.

00:37 So, when is this elevated? When do we end up in macrocytosis? Well, if you have reticulocytes. If they increase, we have reticulocytosis.

00:45 Now, reticulocytes are bigger than mature blood cells.

00:49 They might have a B12 or a folate deficiency.

00:52 They might be taking methotrexate for maybe rheumatoid arthritis, or they're on phenytoin, which we give for seizures.

00:59 So you can end up in macrocytosis with certain medications, nutritional deficiencies, or reticulocytes.

01:06 Now we have microcytosis. They're decreased when a patient has iron deficiency.

01:12 Okay. In case your eyes have glazed over, this is one of the ways that we can figure out what's the cause of a patient's anemia.

01:20 If their MCV is too low, we could consider iron deficiency or thalassemia, or anemia from a chronic disease, hemolytic anemia, or even lead poisoning.

01:30 Now I know that seems like a pretty bizarre list.

01:34 Just keep in mind, MCV is a mean corpuscular volume.

01:38 If it's too low, then know you need to dig deeper and look at the possible reasons that could cause that.

01:44 MCH means mean corpuscular hemoglobin.

01:47 Now this is another calculated value.

01:49 We get it from the measurement of the hemoglobin and the red blood cell.

01:53 We have the formula for you there so you know how it's figured, but we want you to focus on MCH is the average amount of hemoglobin contained within each of the red blood cells.

02:05 If we've got low MCH, we've got some examples that could have come from a blood loss, or an iron deficiency, lead poisoning shows up again, or anemia of chronic disease.

02:15 If it's high, if we have a higher value, might be macrocytic anemia, the red blood cells might be just too big, and that can happen with alcoholism, liver disease, low levels of B12, or folic acid.

02:29 So, the next time you have a patient that you know has had a long history of alcoholism and they've got a CBC drawn, just take a look at the MCH and see what it is.

02:39 It'll be an indication that they have either a history of alcoholism or liver disease.

02:44 If that lines up with their history, you'll start to really understand why these values can tell us so much about your patient.

02:52 Okay. The mean corpuscular hemoglobin concentration.

02:55 Do you understand why we call it MCHC? That's the hemoglobin times 100 divided by the hematocrit.

03:03 And it just tells us the average concentration of hemoglobin in a red blood cell.

03:08 So MCHC is used to help diagnose the type, cause, and severity of an anemia.

03:14 So whether it's iron deficiency, lead poisoning, or anemia of a chronic disease, we would expect a low MCHC.

03:21 If it's high, we're going to really start looking at an autoimmune or an idiopathic hemolytic anemia.

03:27 You'll also see this in your sickle cell kids, or someone who's had a severe burn.