this is going to be the absolute
basics how to read blood test results hey guys how's it going and welcome back to
another video last year i filmed a video called the veterinary basics and it had some really basic
information about what i think was important to know before you go into a small animal clinic
and that was received really well by you guys a lot of you really really enjoyed that video
so i thought i would film something kind of similar and make a little
bit of a series out of it how to read blood test results in particular
a CBC also known as a complete blood count or a haematology report which is basically
the same thing we're not going to be doing serum biochemistry today a whole other aspect
of a blood test that you can do that tells you proteins and electrolytes i'm going to teach
you how to read CBC results today and i just thought it would be helpful because i know when
i first started out and it would give me a blood test results and be like what do you think and we
hadn't really learned it yet and i couldn't even give my two cents now we've learned how to do it
in class and i thought i would tell you the basics on how to do it so that you can do it too when
you go into practice so i'm i'm reading off my laptop in front of me so that i don't get anything
wrong the blood test results that i'm going to be talking about are only for small animals this is
just for cats and dogs just general small animal medicine a CBC report is also known as a complete
blood count or haematology report and it tells you about the cells in your blood which include
your red blood cells your white blood cells and platelets so red blood cells are also known
technically as erythrocytes and white blood cells are known as leukocytes there are five main types
of leukocytes these are neutrophils lymphocytes eosinophils monocytes and basophils if you're in
another country you might do something slightly differently or you might be pronouncing these
words differently to what i am ignore my New Zealand accent we're going to start off with the
red blood cell portion or the erythrocyte part of a haematology report so the first thing that
is normally at the top of your report is hb and this means haemoglobin and the report is telling
you how much or the amount of haemoglobin in one litre of whole blood from that particular animal
haemoglobin is the indicator of how much oxygen that your blood can carry haemoglobin makes up a
huge portion of the actual red blood cell itself pcv which also can be written as HCT means
packed cell volume or hematocrit and this is the proportion of blood like whole blood that is
made up of rbcs we then have rbcs which tells you uh the number of erythrocytes per unit volume then
you have mcv which is the size of the erythrocytes mchc which is the color of the urethra sites you
might get reticulocytes as well and reticulocytes or absolute reticular sites are the immature red
blood cells so say say you're bleeding for example you may need to release more red blood cells
into your system so you're more likely to see more immature red blood cells because your bone
marrow or spleen or whatever is just pumping out as much red blood cells as they possibly can so
an increased number of red blood cells is known as erythrocytosis or polycythemia decreased number
of red blood cells is simple and it is known as anemia in people we often refer to anemia
as because you are iron deficient but anemia can be as a result of a lot of different
reasons other than just iron deficiency if you have erythrocytosis in an animal you will
see increased red blood cells increased hemoglobin and increased pcv normally and this can be caused
by a numerous reasons most often in animals uh erythrocytosis is relative so it's not actually
real can be due to something like dehydration so the fluid or the um plasma in your blood goes
down because you haven't drunk enough water and so it looks like there's more cells in your
blood than there actually is so it's like a false erythrocytosis you can also have a physiologic
erythrocytosis which is when the body rapidly increases your production of red blood cells over
a short period of time disease process like bone marrow cancer or something like that and you have
to do more investigation to figure out which one it is just on the side just a weird and wonderful
fact greyhounds the breed greyhounds they're weird they have a higher pcv than normal animals
so if you are sending away blood to a lab or you're doing a greyhound's blood test results
in clinic you need to be aware that they have more red blood cells than the average dog anemia
is decreased red blood cells hemoglobin and pcv it could be due to increased destruction it
could be due to increased loss such as bleeding or it could be decreased production of red blood
blood cells or a combination of all of the above mchc is the color of the cells we use
chromic as the suffix to describe color if it's within the reference ranges this is known
as normochromic so it's normal color if it's less than the reference range the cells are hypochromic
and if the cells are above the ref reference range then they're hyperchromic they have more pigment
whereas mcv is the size of the red blood cells say the red blood cells are within the reference range
they are normocytic so they're normal sized cells if they're on the lower end or if they're below
the reference range then they are microacidic or they're small cells and if they're above the
reference range then they are macrocytic so large cells so this can be really really helpful when
you're trying to classify the type of anemia or erythrocytosis that you have so for example if
you have a macrocytic hypochromic anemia this is often due to a lot of reticulocytes being in the
blood or immature red blood cells this is because they are larger and paler than your normal mature
erythrocyte so if you have a lot of reticulocytes in the blood meaning it is a regenerative anemia
so loss of red blood cells is regenerating rapidly when you see them in the blood then you can see
a macrocytic hypochromic anemia if you don't see reticulocytes this doesn't mean that your anemia
is non-regenerative it could be pre-regenerative because say if you have blood loss it can take
up to three to five days for these reticulocyte reticulocytes to be in circulation if it's more
than three to five days after blood loss then you know it's non-regenerative and there's something
else going on in the body because your body's not producing red blood cells to replace the
other ones so now we're going to move on to the white blood cell portion of a cbc so white blood
cells are also known as leukocytes leukocytosis is increased white blood cells and leukopenia
is decreased white blood cells neutrophils are the most common white blood cell that we see
in small animals an increase in neutrophils is a neutrophilia and a decrease is in neutropenia
neutrophilia can be due to physiologic response like fear or excitement can also be due to a
steroid response or a stress response due to like high corticosteroids or cortisol in your blood you
can also have inflammation lots of inflammation will cause aneutrophilia in small animals it
can also be caused by cancer but i'm not going to go into that so neutropenia can be due to
really severe inflammation when you're using up all your neutrophils um to the point where you
don't have any left in circulation it can be also due to decreased production and increased
destruction of neutrophils they have a whole life cycle that they go through from the start of their
generation to becoming a big full-grown neutrophil but in the last two stages they have names that we
use so they can be bands or segmented neutrophils these can be both detected on blood smears and
blood tests bands are the more immature version of a segmented neutrophil when you see more bands
say than segmented neutrophils or more bands than you normally would this is called a neutrophilia
with a left shift so it's shifting to the left because it's going towards the more immature side
of the cycle lymphocytes are the next white blood cell that i want to talk about and they are
involved in immunity and inflammation in the body and a bunch of other processes an increase in
lymphocytes is called a lymphocytosis and this can be physiological so um like a fight or flight
response chronic inflammation or another weird disease process and a lymphopenia or decreased
lymphocytes can be seen with a stress response it's most often seen with a stress or steroid
response monocytes are the next white blood cell they're really really big and they do a bunch of
other things around the body like phagocytosis they eat up bad things in the body pretty much so
an increase in monocytes or monocytosis you can see a pattern here this will indicate inflammation
particularly chronic inflammation in small animals and also high levels of corticosteroids or
stress a monocytopenia or not many monocytes has very little clinical significance and we often
ignore it when we see it on a cbc eosinophils or eosinophils or however you want to say it are
these weird little granulated cells increase in eosinophils or an eosinophilia is often seen
with animals that have really bad allergies or a hypersensitivity reaction they can also be seen
when an animal has parasites like in their gut or on their skin like fleas and it can also be seen
with inflammation and a couple other weird disease processes eosinopenia can be completely normal for
that animal it might have no clinical significance but it can also be due to a stress response
or acute inflammation we also have basophils these are quite rare leukocytes and you don't
tend to see them very often uh they are often seen when there's an allergic reaction going on
and they tend to follow eosinophils so if you see a lot of eosinophils you're probably going to
see some basophils as well to kind of summarize i feel like i said stress quite a lot there is
something called a stress leukogram that we see quite often with dogs and cats and it's like a
set type of pattern that we see called a stress leukogram this includes a mature neutrophilia
so lots of segmented neutrophils a lymphopenia and this can also be maybe accompanied by not
always an eosinophenia and a monocytosis and if you see those four things you know that their
animal is either really stressed or you've given given them some steroids recently or they've got
something else going on so now that we've learned all of this i want to put this into an example i
don't want to go into too many details because i'm not obviously a actual veterinarian yet so i'm
just teaching you the absolute basics so here is what a basic normal looking reference chart
looks like got hemoglobin pcv red blood cells mcv mchc reticulocytes for the erythrocyte portion
of the chart and we also have total white blood cells or leukocytes neutrophils segmented
neutrophils bands lymphocytes eosinophils monocytes and platelets we haven't talked about
platelets but um platelets are the third type of blood cell that you'll see if you need to clot
your blood basically platelets are your first line of resort for clotting your blood if you have
increased platelets it's called thrombocytosis and if you have decreased platelets it's called
thrombocytopenia my leg's gone completely numb so numb i've been sitting cross-legged this whole
time these are the reference ranges we're given in class they're slightly wrong i'm really sorry this
is what i'm given by my lecturers so here's an example so we've got animal a um an animal a has
come into the clinic and you've done a blood test on them or a cbc and so you've got the results
back and this is what you see so i just want you to take a minute to look at this chart i just
want you to take note of what you see and try and describe it ideas in your head and now i'm gonna
talk through it so i've gone through the chart and i've made the things blue that are lower than
the reference range and made some things red that are higher than the reference range just to make
it clearer to you from the top down i'm going to describe it and you can say whether you agree or
disagree with me if you've had enough time to look at it so we can see that we have an anemia here
the first three things are below the reference range and this is indicative of an anemia it is
a normocytic normochromic anemia both are mcv and our mchc are within the normal reference range
we also have low reticular science this could be a non-regenerative anemia or it could also be
pre-regenerative it hasn't been three to five days since the insult has occurred next we're going
to move on to the leukocyte portion so the white blood cells so we can see we have a leukocytosis
slightly above the reference range and this is due to a mature neutrophilia because our segmented
neutrophils are high we can also see that we have a lymphopenia an eosinophenia and a monocytosis
and as i mentioned before this is completely classic of a stress leukogram or a corticosteroid
response so yeah that is basically an example of a cvc lots of resources i'm going to leave linked
in the description and probably up here as well for if you want a better teacher than me
hopefully this has helped and given you some more information so next time if you're a pre-vet
student or a vet student like me or you're a high school or something and you're going to do work
experience in a clinic hopefully this will help when you go um into a clinic and a vet shows
you a blood test result for a cbc and you can tell them kind of what you're thinking you won't
be able to give them any answers but i think it might help you open up a discussion with a
vet if your hematology reports or cbc reports are different around the world or
if you learn things differently i would love to know down in the comments
section below let me know what you think of this video and if you are excited by the idea
of a veterinary basics series type thing this is not confirmed and it's just me spitballing
here but if this is something that you guys like i might create pdf documents of these like
information type things and make them accessible to you somehow maybe through a website or
something else like that if it's something that interests you guys thank you very much for
watching let me know if you have any questions complaints or comments down below like if you
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so much for watching and i will see you next time