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Current time:0:00Total duration:10:42

Video transcript

so I have a slip of paper let's go through these lab values I actually put down number of values down that we're going to pretend for a moment are my labs and you can see the range and the units next to them so let's go through it piece by piece and actually while I do it I'm actually going to show you some shorthand techniques so that you can understand if you ever see this in the future what it refers to so this is some shorthand that people have come up with this isn't necessarily something I've come up with I learned it from folks ahead of me but it's been used not just in the US but most parts of the world is pretty pretty uniform so if you're looking at these labs here's a quick way to transcribe them so imagine that you have to quickly put it on a piece of paper and move on this is how you would do it so you draw a little stick diagram like that and in the far left you'd put the number five and this refers to the first row the white-blood-cell row and we know that the value is 5,000 so that's what the five represents and it's understood that that number is in thousands of cells per milliliters so if you see a five you know we're talking about thousands of cells per milliliter the next question is well what are those types of cells if you actually were to look at them we know they're white blood cells but exactly what type they are is actually in the six rows beneath so these six rows tell you the breakdown of this number so that's why they're percents and so the 5,000 cells break down into segments in neutrophils I'm going to write that as an S with a 61 and bands there are 3% bands lymphocytes are 29% and then we have monocytes at 4% basophils at 1% in yoson Ophuls at 2% so these percentages for the different types of white blood cells are going to add up to 100 right so we've got let's just double check we've got seven and twenty nine is 36 and 3 is 39 yup hundred percent so that's how you quickly you can see the different types of white blood cells that are floating around in your body that's what those numbers represent so then the next two numbers hemoglobin and hematocrit go in the top and bottom of this stick diagram and again whenever you see these numbers like this I could look at that and immediately figure out that that's the red blood cell content those two numbers both reflect red blood cell content in the blood and then the last cell on this side represents the platelet count and 227 represents 227 thousand cells per microliter so before we were talking about milliliters for the white blood cells but now for the platelets we're talking about microliters and in fact I'll put cells in quotes because we know it's not really cells these are little cell fragments that are the platelets so that 10 or 27,000 tells you about how many platelet cell fragments are floating around in one microliter of blood so that's the first chunk of data so that's all this information kind of summarized very quickly in that stick diagram let's move on to the chemistry's and so if someone orders a chem-7 then that would be the first seven of these and if they order a chem ten then that would be all 10 of these so this is how you would kind of draw this out as a stick diagram it kind of goes like this and the chem 10 the last three go in here so the sodium goes in the top left and below that is the 4.3 for potassium and just going systematically all the way through it so for chloride it's 103 the bicarbonate goes is 22 right below that then the creatinine goes in this cell 0.8 and then the blood urea nitrogen sometimes they call that the bu n that's just the first letter of these three is 15 and then the fasting glucose is 92 and then the calcium goes in the top of this little wishbone shaped stick diagram that goes right there the magnesium goes on this side and the phosphate goes on this side so that's the chem seven on top and the chem 10 it would be all of that kind of together and then at the bottom we have some liver enzymes and also there's a stick diagram for that as well kind of a fast way to draw it and it's basically just an X the top of the X is two numbers so usually write the total bilirubin like this 1.1 and then you put a slash and then put the other number there the direct bilirubin 0.1 and then on the left you put the ast and on the right you put the alt at the bottom you put the alkaline phosphatase 76 so this is how the numbers kind of break down and so again if you ever see any of these stick diagrams and you're wondering what they refer to now you kind of have broken the code you know what number goes where so if you see you know for example this number 22 you immediately know that they're talking about the alt so this is the the way that people quickly diagram things and now I know when people look at labs the first thing they want to know is hey is this good or bad and so they want to look at these values and they want to compare them to the ranges they want to say hey does this fit into the normal range that people expect so let's talk about that let's talk about normal range and what normal means exactly because I know that's the first thing most people will want to look at so let me draw out what a normal curve would look like so if you actually let's say took everybody let's say 10,000 that's not everybody let's say a big chunk of people 10,000 people and asked them all to tell you their white blood cell count they will give you of course many different numbers probably wondering what you're doing with that information but let's say that give you their answer and let's say you plot it all on a curve and you draw a little diagram this would be basically what you would find you'd say okay most people have a white blood cell this is white blood cell count actually sorry this is white blood cell count down here and this is of course in thousands we said thousands per milliliter thousands of cells per milliliter and this is frequency this is the number of people I'll just write F for frequency so you would say okay while there are a lot of people kind of in this range right here and in fact 95 percent of people fall into this middle section in this area so this is definitely the bulk of people that fit between 4.5 and 10 that's actually how most these ranges are kind of decided to plug they say okay where does the bulk where did the bulk of folks lie and it's usually between those numbers that are in the range and that also means if you think about it that there's of course somebody out here and somebody up here right I mean that that is by definition going to happen you're gonna have 5% of people in one of those two tails combined so whenever you see a range just keep in mind that there are some normal variants they're called that they kind of go above or below that range but that range usually captures the majority of folks so when thinking about that when thinking about what exactly goes into a normal range consider some of the things that could make what is normal differ so for example let's say I check someone's hematocrit let's say I'm looking at the hematocrit and I want to find out if it's normal or not if I look at a baby somatic rate but I use let's say an adult range then it would be very very unusually high so a newborn baby has a very high hematocrit so I really should be comparing it to other newborn babies so age is really important to consider so you want to make sure that the range of values is age-appropriate you also make sure that gender is considered so for example the normal range for men's hematocrit is a little bit higher than the normal range for women's hematocrit so range matters for age and also for gender now different labs will also differ so it's actually quite interesting you can you can even go online and see what the normal range is for a lot of these things that I have here and the numbers will be a little bit different from what I've what I've shown you so if you go from one lab to another you'll get different numbers and in fact lab technique also matter so you even within a lab depending on the technique that they use to get an answer to something the range could differ and that actually matters particularly for things like this so these I use that I put down here they stand for units or international units and that's specific to a certain type of lab assay that's done and again that depends on the exact assay that's done and that's going to change the range of values that you get there so consider the technique and finally consider the situation so if you have let's say a person who is supposed to come in for a fasting glucose and usually you're told you know just don't eat anything overnight and don't have breakfast and come in and get your your blood taken first thing in the morning it's a pretty common scenario then you would have a normal fasting glucose and should be below 100 but let's say by accident you decide to have a little snack in the morning because that's your usual thing you have some toast your blood glucose could go up as a result so that glucose result could be okay if someone knows that you didn't fast really you had a little snack so that situation changed so your metabolism is going to make that range go up so only for fasting glucose is the number below 100 normal otherwise it could be higher now consider a situation where you're taking a medication let's say you're on a medication that causes your potassium to go down so you're on a drug it causes potassium to leave your kidneys and go into the urine your potassium value would then go down I would expect it to be lower right because you're taking your medication and so some of these ranges are going to change depending on what medications you take what what you've had for breakfast that day or not had for breakfast what kind of medical conditions you have so it's going to definitely depend on the situation so whenever you look at ranges and values and you want to see if you're in the normal range just consider all these things that could explain why your number may or may not be within that range