Central Line
Episode Number: 153
Episode Title: Blood Transfusion Concerns and Pulse Oximetry Measurement
Errors
Recorded: January 2025
(SOUNDBITE OF MUSIC)
VOICE OVER:
Welcome to ASA’s Central
Line, the official podcast series of the American Society of Anesthesiologists,
edited by Dr. Adam Striker.
DR. BROOKE TRAINER:
Welcome back. This is
Central Line, and I'm your host for today's episode, Dr. Brooke Trainer. I'm
joined today with Dr. Jason Chi, the editorial board member for SEE or Summaries
of Emerging Evidence. Dr. Chi is going to talk to us today about a few of the
very interesting items in the 41 A issue. I'm really excited to jump in. But
before we get started, Dr. Chi, can you introduce yourself to the audience and
maybe tell us a little bit about how you became interested in the editorial
board for SEE?
DR. JASON CHI:
Of course, Dr. Trainer.
Thank you for having me. And thank you to ASA Central Line for also allowing me
this opportunity to be on this podcast. So my name is Jason Chi. I am a cardiac
anesthesiologist and I live in the San Francisco Bay area, and I work at the VA
in Palo Alto. In terms of my involvement with SEE, I've been involved with SEE
for over ten years now. I actually started with them as a volunteer question
writer. And, um, you know, I've been doing that pretty consistently for 7 or 8
years and then moved on up to the editorial board. And I think it's a fantastic
CME product that ASA offers, and it's a great way for busy practitioners to
stay on top of recent advances and new technologies and new techniques in our
specialty.
DR. TRAINER:
That's awesome. And just
to get us diving in with the 41A issue, I really am interested to know about
the recent item that discussed this article on how we approach patients who
refuse blood transfusions because they don't want blood from donors vaccinated
against Covid. Really fascinating. Can you shed some light on where this fear
is coming from, and why it's important for anesthesiologists to know that this
is a trend.
DR. CHI:
Yeah. So the recent
article was actually published in Anesthesiology, and it was first authored by
Katherine Forkin, who is from University of Virginia. And it's sort of a primer
for helping clinicians guide their way through how to discuss these issues with
patients shen patients come to them with concerns about receiving blood
products from donors who have been vaccinated against Covid 19. So the
background of this is that over the past few years, many practitioners and
anesthesiologists have been reporting that they're encountering patients who
have these concerns, that they don't want blood transfusions if the blood
transfusions come from donors who have been vaccinated against Covid 19. And in
fact, this issue became so common that the American Red Cross and the AABB, the
Association for Advancement of Blood and Biotherapeutics, they actually issued
a joint statement, which was meant to reassure the public that the blood supply
in the United States was safe and is safe for everybody. And what I found
really interesting about this article is that I've actually personally
encountered this on two separate occasions, including one patient in cardiac
anesthesia clinic who was coming before planned cardiac surgery and stated to
me that he did not want a blood transfusion because he was afraid of the
remnants of the vaccine that he thought were going to be transfused to him if
he received the blood transfusion. So I find that this article is very timely.
I thought it was a great topic for the folks from University of Virginia to
tackle, and I think it really helps clinicians to sort of walk through the
steps of, hey, how do I handle this kind of a situation if I'm encountered with
this as an anesthesiologist.
DR. TRAINER:
This is a real concern.
It sounds like, you know, patients with this fear are, you know, it's it's like
assimilated to them having a fear of a poison, you know, being, you know,
poisoned from this. So I think it's important for us to talk here about the
Covid vaccines. And then also, you know, you touched upon it a little bit, but
the safety of our blood transfusions. I mean, what what do we know about this?
What can we let our audience know about this? And then also, why should
anesthesiologists care?
DR. CHI:
Yeah. So I think it's
very helpful that we start with some facts. So first of all, we should just
start with the basics. And we should start with the fact that the virus that
causes Covid 19, which is SARS-CoV-2, it cannot be spread through blood transfusion.
So point blank just cannot be spread through blood transfusion. And the
components of the Covid 19 vaccine also cannot be transmitted through the blood
donations, although for the sake of complete thoroughness is that the part
about vaccine components not being able to be transmitted through blood
transfusions has not been explicitly studied. But to the best of our scientific
knowledge, we do not believe that any of the vaccine components can be
transmitted through blood donations. And in 96% of the US population, actually
has antibodies to Covid 19, either through vaccination or immunity from
exposure. Okay. The other thing is, is that with regards to the blood donors
themselves, it is not possible to determine their vaccination status because
questions about vaccination status, sex, race, religion, um, any of those types
of questions are not required to be documented and are not asked of blood
donors. So vaccination status, it's not possible to say, well, this blood has,
you know, come from someone who was vaccinated And then this blood unit is from
somebody who has not been vaccinated. That's just simply not possible.
I think this is a
really, really important issue for anesthesiologists because, well, for several
reasons. One is that we actually transfuse blood. So we are the ones that are
physically hanging blood and transfusing and checking the units. And number two,
because we are the ones who do the actual blood transfusions and perform blood
transfusions, we are often the people who interface with the patients to
discuss blood transfusions and to make sure that the patients give their
consent for blood transfusions. And in fact, that's what I do every day. As a
cardiac anesthesiologist, I make sure that patients are consented to receive
blood, and I make sure blood is available. And, you know, since we are
literally on the front lines of blood transfusions, I think this is a critical
issue for anesthesiologists to be aware of and to know how to handle.
DR. TRAINER:
Yeah, I think, you know,
it's really interesting times that we're dealing with here. Um, and I think
it's a good point you make. We just don't know. I mean, we don't have the
information on this, you know, the status of these vaccines to be able to, you
know, relay that to our patients. And and the reason we don't know is because
it hasn't been determined that it is a need to know, right? I mean, um, we ask
patients things that we need to know in order to prevent harm, and this is just
not one of them that we ask patients because it's not needed to know whether
it's going to harm a patient. So I think, um, this is really important
information to kind of get out there from, you know, the science community. Are
there other recommendations that can help us best manage these patients?
DR. CHI:
Yeah. And so once again,
um, one of the great things about the article is that they actually kind of go
through, step by step, some really concrete and practical steps that
anesthesiologists can use to approach this issue with any patients that may
have these sort of concerns. You know, some of this is going to sound, you
know, pretty obvious. And, you know, maybe some of the listeners will say,
well, hey, you know, I mean, this is like pretty obvious stuff, but I think
it's really important to reiterate. And so one of the things that the article
mentions is that we as clinicians really need to approach these situations with
empathy, without judgment, and really dispassionately. And we really should
make an effort to try to understand why the patient has requested to refuse a
blood transfusion. Um, we should answer truthfully and respectfully. Um, and I
think that that's really important. And I think, you know, we need to set aside
whatever, you know, personal feelings we may have about this type of issue and
really just focus on what the patient wants and, um, what's driving their
requests. And, you know, try to understand what's driving this refusal. Um, and
then the next step, of course, is after understanding is to refine strategies
to deal with the refusal and then reconcile that conflict and then, of course,
developing the plan. Once again, it may seem like some somewhat obvious to many
practitioners, but simply by saying, you know, you understand their concern.
And that's something that a lot of patients want to hear, that they are being
heard, their concerns are being respected. And regardless of what you may
personally think about it that really, really helps to build that rapport with
the patient to for the patient to feel appreciated and for their, um,
viewpoints, they feel like they're being heard. And so obviously, communication
is really, really at the core of all this and once again, just being
empathetic, non non-judgmental, and just really trying to understand what the
patient is coming from. And that's, you know, that's where you can get off to a
pretty strong start with a patient.
DR. TRAINER:
Okay. So we have a
patient who we're, you know, doing all we can to empathize with them. We're,
you know, really hearing them out. We feel like we've expressed as much as we
can about, with these recommend with these recommendations, but you have a
patient who just continues to express hesitancy about this blood transfusion, specifically
concerning vaccinated donors. So what do we do for those patients? I mean,
ultimately, do we not give them a blood transfusion at all?
DR. CHI:
Right. So, you know,
hopefully not. Hopefully we don't go there. And you know, obviously we are
always trying to act in the best interests of the patients. And so that's a bridge
obviously that we don't want to approach. I think there are a couple of
strategies. One is to highlight the overall safety of the blood bank supply. So
like we mentioned before, you know, I always mention to the patients that the
blood is screened for bacteria, viruses, fungi. And although it's not a, you
know, completely perfect process, it's pretty darn close. And statistically
speaking, the the chance of transmitting a virus is about 1 in 1,000,000
according to the best data that we have. So I think it's always good to
highlight the overall safety of the blood supply. And we can start with that as
a pretty strong foundation.
If you frame the issue
of blood refusal as a question of accepting the risk of serious harm or
accepting the risk of death even, which is a highly likely outcome in the in
the event of large volume hemorrhage, um, rather than the risk associated with
receiving blood from a vaccinated donor. So because a lot of times the the
patients are very focused on the risk of the blood that's coming from the
donor. So they're really focused on, well, if I get the vaccine components or
the spike protein or the RNA or the really sort of fixed on that. But I think
if you sort of reframe it as like, well, hey, you know, there's this risk of
serious harm and there's this risk of death to you, which is a very real risk,
and that's a very likely outcome in the event that we can't transfuse blood to
you. Um, so it's really sort of an issue of reframing to sort of refocus the
risks from abstract risks to real risks. One of the other things is that we can
take some lessons from the experiences going back, you know, decades dealing
with folks who are hesitant about receiving vaccines. It may be more helpful to
educate patients about the harms of having a disease versus trying to tackle
the myths and the false beliefs about the vaccines themselves. Because I think
a lot of times we get sort of caught up in these, you know, tit for tat, you
know, that, well, there's this thing that the patient is saying, which we
believe to be false and that we sort of try to tackle that myth or that false
belief. Um, but, you know, once again, it's sort of a reframing of the
discussion. We're more taking an attack where we say, well, you know, if you
don't have the vaccine, there is this risk of getting a communicable disease. And
the risk of that is very real and the consequences of that are very real. And
and so I found that to that to be very helpful because it really brings
attention to real threats versus the more abstract threats that I think the
patients often present with.
And, you know,
unfortunately, if a patient continues to insist on refusal of transfused blood.
You know, some patients come to us and they say, well, how about giving my own
blood? So we, you know, we call it, you know, autologous donations. And this is
not really sort of a cure all for this problem because and there are a couple
of hurdles that need to be jumped over. One is that the costs of autologous
blood donation may actually not be covered by insurance. And so that may depend
on the insurance company and that may be either approved or not. A lot of blood
bank centers actually don't handle autologous donations because they're not
very common. And they actually require special procedures in terms of clerical
procedures and identification and such, which are very different than handling
blood that's donated from volunteers. And of course, there's the issue of
physiology. You do need about four weeks or so or more ideally, to allow the
patient's blood volume and hemoglobin to recover. And many patients who come
for surgery already have pre-existing anemia or comorbidities. So that could
actually contraindicate that as well. And so I actually receive a lot of
questions about autologous blood donation when patients are scheduled, you
know, for cardiac surgery.
Another one is about
directed donor blood. Once again, you know, the patients can say, well, I have
a family member who's willing to donate blood to me. I would feel much more
comfortable receiving their blood. But once again, that's that is also somewhat
problematic or can be problematic because there is some concern about whether
the donor who is giving the blood has been either pressured to donate the blood
or coerced. And so there is that sort of, you know, lack of clarity. Sometimes
donors who are related can share HLA human leukocyte antigens, and that
actually increases the risk of transfusion associated graft versus host
disease, which can be fatal, although rare, but can be fatal. And once again
with directed donors, you. introduce other points of potential errors such as
transfusion error or clerical errors. There's also the time sensitivity of the
donation, like how long is the blood going to be stored for? How long can it be
good? And then of course, there's also the issue of, well, how much blood would
you actually need if we needed a large volume transfusion? Would this be
adequate because you don't want to give the patient the impression that this
blood is going to be adequate for all the needs of every possibility that could
happen during surgery?
DR. TRAINER:
So this is very
interesting. We're dealing with, you know, almost a new cohort of patients
similar to our like, Jehovah Witness patients, where we really do have to give
perspective on the risk and benefits of blood transfusions. So, you know,
before we dive into the second topic, I just ask if you could, um, sort of zoom
out and give us, you know, a little overview, you know, 30,000 foot view of how
this article can fit fits into the larger context of healthcare in the country.
DR. CHI:
Yeah, I think the larger
context is very, very important. And it really speaks to sort of the state of
affairs of healthcare in this country. I think there's a there's a lot of
things happening. There's a lot of changes, a lot of things that are going on.
Um, and I think, you know, there's no denying the fact that a lot of these
patients come in with this information that they've received over social media
or they've received on TV. And, and there's no escaping that fact that a lot of
our patients are getting their information from very, very a wide variety of
sources and a lot of lot of social media companies, you know, they're just
abandoning efforts at fact checking. So, uh, and that's really not helping the
situation. Uh, I think we also live in a time when there's a lot of decreasing
trust in traditional institutions, such as science and higher education, even
physicians. I think there's a lot of cynicism and, you know, questions about
the motives of health care institutions. Perhaps even then, some of that is
actually directed at physicians as well. So, you know, we sort of had this
perfect storm of these, these different factors which are really working
against the physician patient relationship. And so I think it's all the more we
really need to double down on doing what's best for the patient and really
making sure that the patient understands that they are being heard, that their
concerns are real and we appreciate their concerns. But at the same time, you
know, we have to stick with the science and we have to stick with doing what we
feel is in the best interest of the patient, because that is, you know what
we've taken an oath to do. My suspicion is, is this is not going to be the one
issue sort of one and done. I think clinicians around the country are going to
continue to see patients present with beliefs that are not founded and based on
misinformation. And we're going to continue to see these types of things. And
that's that's a trend.
DR. TRAINER:
I really like what you
said about, you know, validating these patients concerns and hearing them out.
Because oftentimes that's exactly what they need. They just need to be heard,
feel validated, and then be reassured. But let the science kind of guide us.
And, you know, science changes and it evolves. And I think, you know, for us as
clinicians, we need to also be sensitive to the evolving and changing science
as well. Um, so not kind of kind of stuck in our past. So I think I think
that's great.
So a second study that I
want to ask you about, it concerns a recent study that investigated measurement
errors or bias, as we call it, um, between the pulse oximeter measured oxygen
saturation and the arterial oxygen saturation in the settings of low perfusion
and hypoxemia in participants with various degrees of skin pigmentation. So
first, tell us why this topic warrants this special attention.
DR. CHI:
Of course. Yeah. So like
you had correctly mentioned, the the topic is pulse oximetry measurement errors
or also known as bias in patients who have darker skin pigmentation. So what's
actually interesting about this is that it's been known for many years, as far
back as 1990, that pulse oximetry is prone to errors when it's used in patients
who are darker skinned, and the error being that it tends to overestimate the
arterial oxygen saturation. So in plain terms, if the oxygen saturation is
reading 96% on the machine, it not infrequently the actual arterial saturation,
if you were to measure it on a blood gas, would be lower than 96. So this is an
issue that's actually been known for quite a while, but it's been getting a lot
of renewed attention lately. Uh, one of the things that really brought a lot of
attention to this topic, once again, sort of revived, was the study that was
published in the New England Journal in 2020. And that was right in the middle
of the Covid pandemic. And there was a group from University of Michigan that
did this very large cohort study, several thousand patients, and they compared
pulse oximetry errors for patients who were hospitalized and either
self-identified as black patients or self-identified as white. And so, once
again, large cohorts, several thousand people. And they found that for patients
who are self-identified black, they had almost three times the frequency of
occult hypoxemia that was not detected by pulse oximetry. And so the term
occult hypoxemia, what that means is when the pulse oximetry on the machine
measures either 92 to 96 and the actual arterial saturation on blood gas
analysis reads 88 or less. So once again, disparity of somewhere between 92 and
96 on the machine, and then an actual sat below 88. And so they found that that
was much more frequent in patients who were self-identified black. And so this
came in the middle of the Covid pandemic. And obviously, pulse oximetry was,
needless to say, a very critical tool during the Covid pandemic because all the
respiratory complications. And actually, in 2021, a group of Congress members
sent the FDA a letter and they asked them to review pulse oximeter devices. And
actually, in 2023, two years ago, the state attorneys general from 24 states
again. Wrote to the FDA to address these inaccuracies that are happening with
pulse oximetry measurements in people who with darker tone skin. So it's
received a lot of attention in the mainstream media. And. Interestingly enough,
NBC news just covered it again, this topic, only two weeks ago. And so this has
been getting a lot of attention. And and I think this new article which we covered
in SEE, which was published in Anaesthesia and Analgesia, it was a very, very
timely article.
DR. TRAINER:
Yeah. I mean how did
this study shift our clinical practice and how does it impact our clinical
practice? Did FDA, you know, have, has anything happened or has anything been
done about this?
DR. CHI:
Right. Yeah. So I'm
going to back up a little bit. And so a little bit of background. So I think
it's helpful to talk about the study. So the study is from a group from UCSF
and UCSF actually did a lot of the original studies from back in 2005 and 2007.
They have a lab there where they've been looking into this issue for quite a
while. So it's a, it's a study from UCSF. It's a prospective study. It was 146
volunteers, young folks who are in pretty good health. The mean age was about
late 20s or so. And then what they did was they connected them to pulse
oximeters and then drew arterial blood gas samples. So in the study, they
actually drew almost a total of 10,000 blood samples. One of the interesting
things about the study was they actually classified skin pigmentation according
to something called the Fitzpatrick scale. And so that goes from a scale of 1
to 6. One is being the lightest pigmented and then six being the darkest
pigmentation. Whereas, and this is in contrast to previous studies where
previous studies used self-reported race as a surrogate, and one of the great
things about this study, too, is they actually used pulse oximetry machines
that are widely in use and perhaps even used for a lot of the listeners who are
listening in on this podcast. One is made by Masimo and one is made by Nellcor.
And so these are actual machines. These are not, you know, something that's
tucked away in some lab and that nobody uses. But these are actually machines
that are in clinical use around the country. And what they wanted to look at
was the interaction between skin pigment perfusion, like how well perfused the
peripheral, you know, extremity is, and then the degree of hypoxia. And so they
wanted to see if there's any interaction between skin pigmentation, how well
you're being perfused, and then how hypoxic you are. And the way they did that
was they would actually create hypoxic conditions through a mouthpiece into
these volunteers. And the volunteers would breathe like an air, nitrogen and
carbon dioxide mixture until they reached, um, like sort of a stable level of
hypoxia. And then they would draw blood gases and compare the oxygen saturation
from the blood gas to what was being reported at the exact same time on the
machine. So in terms of sort of a methods perspective, the methodology here
used is very, very excellent. It's a prospective study. Um, you know, they
really nailed down the classifications of the skin color. And then and then
also they used these pulse oximetry machines which are being used in clinical
practice. So methodologically very very sound studying.
DR. TRAINER:
They must have used
medical students to get hypoxic to convince them.
DR. CHI:
Probably, yeah.
DR. TRAINER:
I mean, you explain why
it matters and how it was conducted. Um, you know, so what's new here? You
know, what did the study find is, um, and is it going to shift our
understanding of it? Are we going to be changing things in our clinical
practice?
DR. CHI:
Well, what the study
found was not not really surprising. The what the study found was pretty
consistent with what we've seen before. So three things. One is that the worse
your perfusion, the larger the amount of error in pulse oximetry. And this is
probably something that a lot of clinicians, a lot of anesthesiologists, have
suspected. These guys have shown that this group from UCSF, they've shown that
the worse your perfusion is, the larger the amount of error in the pulse ox
machine. Number two. Is that the worst your hypoxia gets, the error in the
pulse oximetry machine actually gets bigger. So the lower your actual oxygen
set is, the larger the amount of error that the machine is going to give you.
And once again, I should say this is not 100% of the time. This is not like 100
out of 100 patients when they get hypoxic, there's going to be errors on the
machine. That's not what I'm saying, but I'm just saying that the chances of
those errors get higher and the the degree of those errors also increases. In
terms of skin pigmentation, once again, no surprises here, but confirmed what
the previous studies have found is that in darkly pigmented volunteer subjects
with low perfusion, hypoxia gets missed a lot of times. So for one of the
devices, it actually missed a diagnosis of hypoxia in up to 30% of patients. So
once again if the machine is reading between 92 to 96. And so let's say you're
in the operating room and the machine is reading, say, 93. Um, but if you have
a patient who has poor perfusion and who is darker skin tone, then that reading
of 94 may actually be incorrect up to 30% of the time. Up to 30% of the time,
the actual set is going to be lower than 88%. And that's what this study has
demonstrated. And so that's why it's so powerful because in terms of clinical
practice, this is, regardless of say, it's very important because we don't know
that the actual number that we're seeing on a pulse ox machine is the actual
oxygen saturation.
Um, and so, you know,
what does this study add? It confirms the findings from previous studies that
poor perfusion and skin pigmentation, these all sort of interact and conspire
against an accurate diagnosis from the machines. Uh, it has a lot of implications
because we all know that pulse oximetry is used universally around the world.
And so this is this is a potential finding that has really, really, I mean,
without hyperbole, has worldwide type of implications. One of the things that
this study adds is the variable of poor perfusion. And so it's not just simply
a matter of skin tone equals larger errors but poor perfusion by itself. And we
know there are many, many various disease states or iatrogenic causes of poor
perfusion. So, you know, peripheral vascular disease or hypothermia or use of
vasopressors. These can all cause poor perfusion. But once again that did this
study adds that variable and says, hey, poor perfusion can actually affect the
amount of error and the frequency of error of your pulse ox machine.
And so as a practical
clinical matter, I'd say for me in my personal practice, that may even mean I
have a lower threshold to insert arterial line for cases in which I'm, you
know, sort of thinking about it, um, in which these variables are going to come
into play in terms of poor perfusion, in terms of skin tone, that sort of
thing. And then finally, I think it's a good reminder, like you had mentioned
earlier, that, you know, science is always changing, right? And so this is a
great reminder of that. It's also a reminder that machines and technology are
not infallible, that just because a machine is giving you a number doesn't mean
that it's, you know, 100% accurate 100% of the time. And so I think this is a
it's a great article. And it's it's a little bit of a wakeup call I think to us
as well. But um, it really, um, goes to show us that we really need to stay on
top of these changes because they do have clinical implications.
DR. TRAINER:
You know, being a
critical care physician -- so I work a lot in the ICUs where, you know, I could
see us looking at, you know, these patients a little bit differently. You know,
we have our COPD patients, for example, where we tell the nurse, you know,
titrate the oxygen to 88%. But you know, what about, you know, our patients
with darker skin pigmentation? I might actually change my clinical practice to
where I'm going to, for darker skin pigmentation, raise that minimum threshold
up because of how dangerous we know that, you know, end organ perfusion is
dependent on oxygen saturation and and blood flow. Right. So if you know now
that we know this and this is out there, we really should be thinking about it
more. And you know, I just wonder are we going to officially work to change our
parameters for those low those low thresholds for patients with darker skin
pigmentation? Maybe we have to, you know, rely on that Fitzpatrick scale to do
that. It's really interesting.
Um, so final question
before I let you go, I would love to hear a bit about the work that you're
doing with SEE. And if there's something you'd like to share with our
listeners, you know, who may not know a whole lot about the program. Um, so if
you would just take us behind the scenes a bit to share some of your
experiences with the committee?
DR. CHI:
Sure. Yeah, absolutely.
Um, SEE is S.E.E. It's an acronym which stands for Summaries of Emerging
Evidence. It is a CME product for practicing clinicians, um, also for
residents, but more directly more directed toward practicing clinicians. It's
available through the ASA, and you can receive 30 hours of CME credit every six
months. So in one calendar year, you could receive up to 60 hours of CME
credit. It's available in a paper and online format as well. It's available
through the app. And the great thing about it is you can go at your own pace.
You don't have to go to a conference and you don't have to travel anywhere.
One of the things that's
unique about SEE is our mission is to highlight new and emerging evidence. So
what does that mean? So that means new techniques, new medications, new study
findings. Um, the application of technology such as AI. And that's, you know,
that's been a hot topic, of course. And any kind of new findings around the
world, not just in American journals, but just from journals and publications
all around the world. And the SEE is run by an editorial board and also by ASA
staff members. And the editorial board has 12 people. What we do is we review
30 different medical journals that have some kind of relevance to anesthesia.
So all the major medical journals that have any kind of relevance to our field
of anesthesiology, each of the editors goes through those journals literally
every month and hand picks articles that we think highlight new and emerging
evidence that is going to be clinically relevant for practitioners. And so this
is a great way for subscribers to stay on top of the latest developments and
stay on top of new developments. And we do all the work for you. You know, the
editorial board does, you know, we pick the articles and we read them for you.
We summarize them and then we put them into a question and answer format. You
don't get graded. Nothing like that. But the question is merely to pique your
interest. And then we have a 4 to 5, you know, sometimes six paragraph
discussion about a certain article. And so once again, the two articles that we
had talked about today, the blood transfusions and then the darker skin
pigmentation and pulse oximetry, those are articles that were published in
anesthesiology and in ANA. And then we highlighted them in SEE, and we wrote a
question and discussion based on those two articles. So just to you know, in
summary is SEE I think it's a I think it's great. I use it myself personally,
even though I'm on the editorial board, I use it myself to get CME credits
because I find it to be so helpful and very interesting. I think it's a great
way to stay on top of new developments, and it's a great way to get CME credits
as well. So yeah, that's what SEE is about.
DR. TRAINER:
Absolutely. And Dr. Chi,
thank you so much for sharing your time and your invaluable expertise with us
today. I mean, I found myself just shaking my head listening to this really
thoughtful discussion. And I really appreciate I know our listeners do too.
Your time, your thoughtful analysis, and, you know, your ability to break down
these critical issues. For our listeners, it's really a pleasure to learn from
from you. You're so knowledgeable with all of this. So thank you.
DR. CHI:
Thank you. You're too
kind. Yeah. Thank you. Thank you, Dr. Trainer, for having me. And, uh. Yeah,
it's it's it's been a pleasure.
(SOUNDBITE OF MUSIC)
DR. TRAINER:
Yeah, absolutely. And
for listeners who want to learn more about these topics or see in general,
Please visit us at asahq.org/SEE.
VOICE OVER:
You can't read everything, so SEE does it for you. Learn what the
specialty is learning on your own time. SEE is available now, with insights
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