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The Elephant in the Room with Mike Wenninger · Style Points

0:09
Hello, anesthesia enthusiasts, and welcome to
0:11
another episode of Style Points. I'm your host,
0:14
John Crow. Today on the podcast, I'm sitting
0:16
down with Dr. Mike Winninger, the director of
0:19
animal health at the Cincinnati Zoo, to talk
0:21
about what anesthesia looks like when your patients
0:23
include fish, penguins, venomous snakes, and
0:26
elephants. Long -time listeners may remember
0:29
Episode 5, when my colleague Brian Vaughn told
0:31
us about doing anesthesia for the gorillas at
0:33
the zoo. Before we get there, I'll hand it over
0:36
to my co -host, Nate Moore, to introduce this
0:38
month's RSI, which of course stands for Resident
0:41
Selected Information. Thanks, John. I'm welcoming
0:45
Dr. David Karnbaugh back to the program. You
0:47
last heard from him as an intern, and we're lucky
0:49
to have him back as a brand new CA -1. He's gone
0:52
above and beyond digging into an emerging concern
0:55
regarding anesthetics in patients with Venezuelan
0:57
ancestry, so this will be important to listen
0:59
to before you do your next pre -op. Welcome,
1:02
David. Hi, everyone. This is David, one of the
1:05
anesthesia residents here at UC, and today I
1:08
wanted to talk about an emerging patient safety
1:10
issue that's generated a lot of discussion in
1:12
the anesthesia community over the past few months.
1:15
Recently, anesthesiologists around the world
1:17
started noticing healthy children and adults
1:19
developing devastating neurologic injuries, including
1:22
strokes, prolonged coma, and even death after
1:25
routine anesthetics. It started with reports
1:28
from anesthesiologists in South America that
1:30
were believed to be isolated events. But as word
1:32
spread through the anesthesia community, additional
1:35
similar cases were identified in Europe and the
1:37
United States. As investigators looked more closely,
1:41
a pattern began to emerge. Many of the affected
1:43
patients shared one important characteristic.
1:46
They were of Venezuelan maternal ancestry. Family
1:50
histories also revealed that, in several of these
1:52
cases, relatives had also experienced similar
1:55
unexplained complications after anesthesia. That
1:58
observation prompted genetic testing, which identified
2:01
a mutation in mitochondrial DNA involving the
2:04
ND4 gene, a gene responsible for encoding part
2:07
of complex 1 of the mitochondrial electron transport
2:10
change. So what is the significance of this?
2:14
Well, Complex I is responsible for the first
2:17
major step in oxidative phosphorylation and the
2:19
generation of ATP, which our cells are dependent
2:21
on for energy. The brain is especially dependent
2:24
on continuous ATP production, and volatile anesthetics
2:28
are actually known to inhibit Complex I. As a
2:31
result, the leading hypothesis is that patients
2:33
carrying this mutation may have mitochondria
2:36
that function normally under everyday conditions,
2:38
but become unable to meet the brain's metabolic
2:41
demands when exposed to these volatile anesthetic
2:43
agents, resulting in profound neurologic injury
2:46
in an otherwise healthy patient. It's important
2:49
to emphasize that this mechanism is still under
2:52
investigation. We don't know exactly yet why
2:55
these complications occur and why only certain
2:57
individuals appear susceptible. We also don't
3:00
know which anesthetic technique is truly safest,
3:02
as propofol can also affect mitochondrial function,
3:05
although the relative risk between volatile agents
3:08
and propofol in these patients remain unknown.
3:10
To date, only about 36 known or suspected cases
3:14
have been reported worldwide, making this an
3:17
exceptionally rare phenomenon. However, because
3:20
of the severity of the outcomes, the American
3:22
Society of Anesthesiologists and the Society
3:25
for Pediatric Anesthesia felt the evidence was
3:28
compelling enough to issue a joint communication
3:30
to practicing anesthesiologists. First, they
3:33
encouraged anesthesiologists to ask patients
3:36
about maternal Venezuelan ancestry when obtaining
3:38
a preoperative history. Because mitochondrial
3:43
DNA is inherited exclusively from the mother,
3:45
maternal lineage is particularly important. They
3:48
also emphasize approaching these conversations
3:50
with sensitivity and making it clear that the
3:53
questions are intended solely to identify patients
3:55
who may benefit from additional evaluation. Even
3:59
more importantly, a negative family history doesn't
4:01
eliminate the possibility of risk. Because mitochondrial
4:05
disorders can have variable expression, someone
4:08
may carry the mutation even if no relatives have
4:11
experienced complications. For patients considered
4:14
at risk consultation with genetic specialists,
4:16
and consideration of targeted testing for the
4:19
specific ND4 mutation may be appropriate. The
4:23
next recommendation is in regard to anesthetic
4:25
management. While we still don't know the safest
4:27
anesthetic technique for these patients, current
4:30
expert recommendations are to avoid volatile
4:32
and inhaled anesthetics when possible and consider
4:35
regional anesthesia if it's appropriate for the
4:38
procedure. Additionally, they also recommend
4:41
employing process EEG monitoring, such as a BIS
4:44
or SED line, throughout the perioperative period
4:46
in order to avoid burst suppression. It is also
4:49
worth noting that a few patients reportedly underwent
4:52
propofol -based anesthetic without complication.
4:55
However, propofol can also inhibit mitochondrial
4:58
functions, so we simply don't have enough evidence
5:01
yet to conclude that it's the safer alternative,
5:03
particularly for prolonged infusions. We can
5:06
consider the use of agents such as midazolam,
5:09
dexmedetomidine, and ketamine, which have not
5:11
been associated with complications in this population.
5:14
Finally, if a suspected case does occur, anesthesiologists
5:18
are encouraged to report it through their institutional
5:21
patient safety systems and the anesthesia incident
5:24
reporting system so that additional data can
5:26
help guide future recommendations. Overall, Anesthesia
5:30
has always been personalized based on a patient's
5:32
physiology, medications, and medical history.
5:35
And increasingly, we're seeing that genetics
5:37
may just become another critical piece of that
5:39
puzzle. Just as malignant hyperthermia changed
5:42
the way we think about inherited anesthetic risk
5:44
decades ago, the emerging mitochondrial disorder
5:47
reminds us that our understanding of pharmacogenomics
5:50
is still evolving. As more cases are identified
5:53
and studied, we'll hopefully gain a clearer understanding
5:55
of which anesthetic techniques are safest and
5:58
why these complications occur in the first place.
6:00
Until then, awareness, thoughtful screening,
6:03
and continued reporting suspected cases remain
6:05
our best tools. Thanks for listening. Mike, thank
6:11
you so much for joining us. Before we get into
6:14
it. Let me ask you one of my favorite interview
6:16
questions, which is my dinner question. If you
6:19
could have dinner with anyone in the world, could
6:21
be somebody from the past or even from fiction,
6:23
who would it be? Well, I'm not someone who is
6:26
really awestruck by celebrities or anything like
6:29
that. Sure. I kind of just, I'm a herp guy. Like
6:34
I like reptiles a lot. So I'll use the cliche
6:36
answer and say Steve Irwin. That's fantastic.
6:41
Tell me more. What would you talk to him about?
6:44
Well, I would ask him how it's so easy for him
6:47
to find the reptiles, because when I look, it
6:49
takes me forever to find a single specimen. And
6:51
it just seems like every time he looks anywhere,
6:54
there's one there. So I also kind of think they
6:56
were planted. Oh, yeah, I imagine so. It would
7:03
be really interesting to get behind the scenes
7:05
with Steve Irwin. I heard his son does a lot
7:09
of stuff, too. Yeah, I haven't really paid much
7:11
attention lately, but yeah, I know he's kind
7:14
of carrying on the legacy. So speaking of herpetology,
7:19
I read that you found your first snake when you
7:22
were four, and you've just been all in after
7:25
that. Can you tell me more about that story?
7:28
Yeah, my parents made the mistake of telling
7:30
me when I was a little kid that if I could find
7:32
a snake, I could keep it. And I didn't stop looking
7:36
until I found one. I found a baby red bellied
7:39
snake. And at the time it was, you know, before
7:41
internet. So we called the local like DNR people
7:45
and said, Hey, what do these things eat? And
7:47
they're like flies. I'm like, that's cool. Cause
7:50
they don't really like that. So it didn't live
7:52
long. So maybe that's what, what changed or helped
7:58
me to be where I am now. I don't know, but now
8:00
I like to fix things because I. obviously when
8:03
i was four really messed up or my parents did
8:06
so tell me more about how you came to pursue
8:12
veterinary medicine and how you became who you
8:15
are and tell us who you are what what you do
8:18
and what your life is like a big question yeah
8:21
um i've always loved animals and i've always
8:24
which is also every single veterinarian will
8:27
tell you that but i also really like fixing and
8:30
figuring out problems so i knew i wanted to do
8:33
medicine and it just was a natural fit i had
8:37
at one point thought about doing human medicine
8:40
but then i realized that humans are gross and
8:42
animals aren't which isn't entirely true a lot
8:46
of animals are also gross So I just decided that
8:50
would be the path I wanted to pursue. I grew
8:54
up. My family didn't have much for money, so
8:57
I wasn't able to go from vet school to multiple
9:03
internships and then a residency and then become
9:05
a zoo vet. So I took the very scenic route to
9:08
my career. So I grew up, went to undergrad at
9:12
UW -Madison. I was there for three years. I got
9:16
into vet school a little bit early, which helped
9:18
save money. Went to vet school at UW -Madison
9:21
and then went into private practice and did exotics
9:24
and companion animals for about 14 years before
9:28
deciding I wanted to make the switch to full
9:30
-time zoo. So how did you get into an exotic
9:35
animal private practice? That seems interesting.
9:39
I don't know how any of this works. Well, if
9:41
you're willing to see them, not a lot of people
9:43
are. Well, now more people are. But at the time,
9:46
there weren't a lot of people really interested
9:48
in treating birds and reptiles and small mammals.
9:50
And a lot of smaller zoos couldn't afford to
9:54
have a full -time veterinarian on staff. And
9:56
so I worked for a bunch of smaller zoos just
9:59
to help provide care for their collections. And
10:01
so I got a ton of experience that way. About
10:05
40 % maybe of my clinical caseload were exotics
10:09
for 14 years, so a lot of patients then. And
10:13
then I was lucky enough to get a position out
10:16
in California at the Fresno Chaffee Zoo. And
10:19
I was there for four years, saw the position
10:22
open up here, and I really wanted to get back
10:25
to the Midwest. I'm from Wisconsin. I wanted
10:27
to be close to family. The zoo here is awesome,
10:29
and it's one of the best zoos. It's a great position.
10:33
I have all the support in the world and I love
10:35
it here. I can confirm that the Cincinnati Zoo
10:38
is awesome. I have the whole family membership
10:42
and everything else. So I love walking through
10:45
and seeing all the animals, especially having
10:49
been given the opportunity to take care of a
10:51
couple of the gorillas here. I wonder if you
10:55
could talk a little bit about the partnership
10:57
that the. UC's anesthesia department has with
11:03
you guys and what we do with you. Yeah, it's
11:07
a great partnership. So we, you know, we kind
11:10
of have to know about anesthesia for all the
11:12
different species we have, everything from like
11:15
our insects and fish and amphibians, reptiles,
11:18
birds, mammals, all the things. And the one thing
11:22
that one like group of animals that we see here
11:26
that there are people who are obviously better.
11:30
or more knowledgeable at would be our apes because
11:32
they're so closely related to people. So for
11:35
any kind of longer or more involved procedures,
11:38
it's nice to have human anesthesiologists here
11:41
who can treat these guys more similarly to a
11:45
human than to most of the other animals that
11:48
we work with. So it works out really well. And
11:51
yeah, everybody's been super accommodating, great,
11:53
great partners. So with Gladys and her broken
11:57
arm, i remember talking to my colleague dr brian
12:01
vaughn about it and he told us about the conversation
12:05
about whether or not to do a nerve block and
12:07
ultimately decided not to because gladys wouldn't
12:11
really understand with her arm being numb i wonder
12:14
from your side what what was that thought process
12:17
and conversation like well i think we just didn't
12:21
know how she would respond um I wasn't 100 %
12:25
against doing nerve blocks. It's just sometimes
12:27
if they can't feel it, they might like chew at
12:30
it or she was already hurting a lot. So we did
12:34
provide a lot of analgesia for her. So she didn't
12:37
seem painful post -operatively. So it worked
12:40
out really well. I think there were also local
12:42
blocks like at the surgery site and things like
12:44
that. Yeah, that makes a lot of sense. I have
12:49
to name check another famous Cincinnati animal.
12:52
I wonder. Have you gotten the chance to work
12:54
on Fiona before? Is that one that you're pretty
12:57
familiar with? Yeah, I think everybody in the
13:00
zoo is real familiar with Fiona. She's a little
13:02
bit of a diva, and she kind of does what she
13:04
wants. She's actually really well trained, and
13:07
her keepers are great with her, along with the
13:11
rest of the hippos. So she's trained to let us
13:14
get blood from her, do exams like oral exams
13:16
and ear exams, and we can ultrasound her abdomen.
13:20
It's a little tough because she's quite thick.
13:22
I imagine. But, yeah, we can do a lot of diagnostics
13:26
with her. The only thing we've had in the last
13:30
few years with her is when she cycles, she gets
13:32
a little hormonal, so sometimes her attitude's
13:35
off a little bit. And then she also had an ear
13:39
infection, which was quite challenging because
13:41
hippos kind of close their ear canals when they
13:44
dive. And so when you go to put things in their
13:48
ears, it doesn't always get to where you need
13:51
it to go. Have you ever anesthetized a hippo?
13:55
Is that something that you guys do? How does
13:57
that work? I haven't had to do hippo anesthesia
14:01
because since I've been here, this is the only
14:03
zoo I've been at where we have hippos. So I haven't
14:07
had to do it, but Dr. Jenny here has had to do
14:10
it before. And you just need a really long needle
14:13
to get through their subcutaneous tissue. And
14:17
otherwise, just maintaining an airway and doing
14:19
the things you would do for any other animals.
14:22
Yeah, I want to talk about some of the larger
14:26
animals here in a second. But before I do that,
14:29
I saw in your email signature, you have the DVM
14:33
credential, but there's another one that I thought
14:37
looked kind of interesting, which was the aquatic
14:39
certification. Can you tell me what that means?
14:42
What's that about? Yeah, so it's just a certification
14:45
that you can get. Pretty much, it just says you
14:49
have a... You've met standards for care for aquatics
14:53
and the aquatic certification. Like it covers
14:58
like fish, but also aquatic birds and diving
15:01
birds and aquatic reptiles and amphibians as
15:04
well. So it kind of tracks along really well
15:08
with my love for herps. And yeah, like fish anesthesia
15:13
is really, really fun. Tell me about that. I
15:16
just I have a hard time picturing fish anesthesia.
15:20
Well, their gills are kind of like our lungs
15:22
and their water is kind of like our oxygen or
15:26
air. So essentially we mix up different concentrations
15:31
of anesthetics with water and then we run it
15:35
across their gills. And then by changing the
15:37
concentration in the water is similar to changing
15:40
like the concentration for an inhalant gas. So
15:43
we can keep their level of anesthesia. where
15:48
we want it based on what the concentrations are.
15:50
So what kind of drugs are you using? Are you
15:54
mixing into their tanks? You can use all sorts
15:57
of different ones, and you can also do injectables,
15:59
but they're not generally as predictable and
16:04
not as quickly reversible. So we use a drug called
16:07
MS -222, which comes as a powder, and I don't
16:11
believe it's used in any other species besides...
16:16
Fish and some some aquatic other aquatic animals
16:19
will respond to it. Some don't respond at all
16:22
to it like Some crayfish. No, they show no response
16:26
They'll actually if with crayfish some species
16:30
if you have it even high enough that it's precipitating
16:32
out of the water so you've Like you have your
16:35
max concentration. They'll carry it around And
16:39
it does nothing to them so we don't use it for
16:43
them, but we do for fish and It really works
16:47
really well. And as soon as you switch them back
16:49
to fresh water, it's kind of like turning off
16:50
anesthetic gas once you start flushing fresh
16:52
water, either salt or fresh water, I guess. Across
16:55
their gills, they recover really, really quickly.
16:58
What kind of analog in human medicine would that
17:04
MS -222 -32 drug have? I'm not sure there is
17:11
one, to be honest. Really? Wow. That's really
17:13
interesting. So how do you know when the fish
17:15
is asleep? What are you looking at? It's really
17:17
technical. They float. That's not entirely true.
17:25
I mean, they do float, some of them. Some of
17:27
them don't float, but you see their opercular
17:30
movements, which would be equivalent to our respirations.
17:34
You see those slow. You see their movements.
17:38
They will show similar ataxia. like a mammal
17:43
would. It's just they're in a water column, so
17:45
they won't maintain their place in that water
17:47
column. So if you're doing a procedure, I guess,
17:51
are you doing like a removal of a tumor or something?
17:56
Are you doing that under the water or how does
17:58
that work? You usually put usually put them in
18:02
like a like a foam wedge and submerse them mostly
18:07
in the water and then have like the like a tube
18:12
going into their mouth and across their gills.
18:14
And so their body will stay mostly in the water
18:18
that they're in, but the incision site will be
18:20
out. So things like mass removals or like celiotomies,
18:24
we see sometimes oophoritis in our female fish.
18:27
And so essentially you just spay them. Oh, okay.
18:31
That makes sense. Is there such a thing as a
18:34
fish that would be a bad anesthesia candidate?
18:38
Yeah, so there's horrible anesthesia candidates
18:41
that are a pain in the butt. So things like,
18:44
there's two kind of groups that come to mind.
18:46
One are any of the fish that can breathe air,
18:48
because when you put anesthetic, you put MS -222
18:53
in the water, then they come and gulp air and
18:55
they don't go to sleep. So that's a real pain
18:59
in the butt. So those guys, sometimes you have
19:00
to use injectables along with the additives to
19:04
water. and then the other ones that are more
19:07
challenging are the fish that are like um like
19:10
ram breathers like some of the sharks where they
19:12
have to be constantly moving so sharks and rays
19:15
which we don't have sharks or rays here we've
19:18
worked with some at the aquarium we have a really
19:20
great relationship with the aquarium here too
19:22
but in fresno we had a large number of rays and
19:27
some sharks and so we would constantly they have
19:30
to constantly be moving so we would be um just
19:33
increasing the flow across their gills. So why
19:36
do they have to constantly be moving? They don't
19:39
have a great way of respiring, so to move, they
19:45
essentially open their mouths and move and ram
19:49
the water through. Oh, okay. Wow. I imagine that
19:53
would make it really challenging to anesthetize
19:55
them. Yeah, it works out pretty well as long
19:59
as you... As long as they're moving around when
20:02
they're falling asleep, and then once they're
20:04
sleeping, you just need to make sure that the
20:05
flow across there, their gills are out their
20:10
spiracles. Are there any, like, disaster situations
20:13
that can happen in a fish anesthetic? Yes, sometimes
20:17
they can get too deep. They can have all the
20:20
same, like, negative, like, adverse effects that
20:23
other species can. I haven't actually ever, I
20:27
haven't anesthetized tons of fish, and... I haven't
20:30
had any complications. They seem to do pretty
20:32
well with MS -222. Oh, that's good. Okay, so
20:36
let's go to the other end of the spectrum and
20:39
go to the very large animals. What is it like?
20:43
What is the hardest part of anesthetizing an
20:46
elephant, say? Well, a lot of elephants of the
20:51
megavertebrate species are kind of, they're probably
20:55
among the more. Not predictable as far as how
20:59
they react to anesthesia, but most of them are
21:01
so well -trained that you can do things like
21:04
IV sedations or things like that. We do have
21:09
to sometimes dart them as well, but a lot of
21:11
times you can do things that you wouldn't be
21:13
able to do with a more wild or untrained animal.
21:17
So the biggest thing for those guys is just making
21:20
sure that you can establish an airway and that
21:23
you can... They're so heavy, you need to be able
21:26
to... to breathe for them to ventilate them so
21:29
getting them into an appropriate position sometimes
21:31
is quite challenging um there's actually um there's
21:37
like a oxygen demand valve kind of thing that
21:39
we use um we call it the zubinator because um
21:43
zuba is the last name of the veterinarian who
21:46
developed it but it's essentially like um you
21:50
can force like large volumes under pressure of
21:55
oxygen into their lungs and so we use that if
21:59
we have to luckily here we haven't had to our
22:01
elephants have been generally healthy and when
22:04
we've had to do things we've been able to do
22:06
it with sedation and local blocks so we haven't
22:08
had to do general anesthesia here in cincinnati
22:12
yet i read the uh you treated sabu's arthritis
22:16
with injections to the elbows and that you consulted
22:21
a pain medicine specialist and i was just curious
22:23
if you could tell me more about that yeah so
22:26
we um dr matt brunke is a pain medicine specialty
22:30
veterinarian he presented at the association
22:34
of zoo vets conference and we reached out to
22:37
him after and we talked about a bunch of different
22:39
options everything from like giving like Arthramid
22:42
in the joint to stem cells to like PRP and all
22:46
those things. And so we decided to do Arthramid.
22:49
And so he flew out here for the first time. And
22:52
then we've done it a few times since then without
22:54
him here. But essentially, we just do standing
22:58
sedation and then locate the joint space with
23:04
x -ray and ultrasound and then just do an intraarticular
23:07
injection. We also collected. um synovial fluid
23:11
for cultures and um like sequencing and cytology
23:15
things like that so i'm really fascinated by
23:19
the positioning aspect of it how can an elephant
23:22
safely lie down how does that work well for for
23:26
us we're when we're doing our sedation we hope
23:29
that they don't lay down um when they do um you
23:34
just need to not be under them as they're laying
23:36
down which sometimes is easier said than done.
23:40
I mean, it's easy enough to get out of the way,
23:42
but, um, and they usually show, show signs that
23:45
they're going to lay down when they're sedated,
23:47
but the goal is to do it in standing, um, through
23:50
standing sedation. Um, Sabu actually did lay
23:54
down and, um, we have, um, kind of like a, it's
24:00
a thing called like a tripod, but essentially
24:02
it puts a sling under him and then uses leverage
24:04
to help support weight. So we're able to kind
24:07
of hold him off, um in a normal like or in a
24:10
position that he could breathe easily even though
24:13
he was sedated and he had his elbows actually
24:15
flexed and so for him it made it really easy
24:17
to give him his joint injections because his
24:19
elbows were in a wide open easy space when we
24:22
did one of our other elephants she stood well
24:25
so her sedation didn't get as deep and we didn't
24:28
need to sedate her more and so it was a little
24:30
harder to find her joint space but it was a lot
24:32
easier because she not from a sedation perspective
24:35
because she never actually laid down wow so how
24:38
many people are in the room for something like
24:40
that well we do it in their holding space you
24:45
probably have maybe 20 people right around them
24:52
and then another like 20 people or so um ready
24:57
to respond if there's any um problems um we also
25:01
first boo because we didn't we know that he had
25:04
He has some elbow arthritis, and so we didn't
25:07
know how well he would get up if he went down.
25:09
So we actually removed from our elephant track
25:11
building, we removed one of the skylights and
25:14
had a crane brought in and lowered down so that
25:17
if he were to go down, we could lift him up off
25:20
the ground with a crane. Luckily, we didn't need
25:22
to do that, but we had it in place just in case.
25:24
There's a lot of planning that goes into those
25:27
procedures because you don't ever want to be
25:29
in a situation where you just can't get them
25:31
up. I've had some heavy patients personally,
25:35
but I've never thought about bringing in a crane.
25:39
That's amazing. That'd be really embarrassing
25:41
if you had to bring in a crane. Let's talk about
25:46
some of the cold -blooded animals and penguins
25:50
and the reptiles and such. I remember seeing
25:55
on your board earlier today that you're going
25:58
to do a CT on a penguin. Is that right? Yep.
26:01
So he's a little penguin who has a beak injury.
26:06
And so we're just doing a CT to see whether there's
26:09
bone involvement. His white cell count's been
26:12
normal and he's otherwise seems clinically normal.
26:15
So we think it's primarily like a trauma, like
26:17
he got it smacked on something. But we want to
26:20
make sure there's not any infectious component
26:22
or anything like that. So we're going to assess
26:23
him more today. So for them, because they have
26:27
dive reflexes, just like. Um, like the pinnipeds,
26:30
like seals and sea lions and things. And, um,
26:33
obviously like cetaceans all do, but, um, you
26:37
just, you premed them so that they're, um, you
26:39
don't need as much gas and so that you can maintain
26:42
a more smooth level of, um, anesthesia. And,
26:46
um, they're actually pretty, I mean, the penguins
26:48
are pretty simple for anesthesia. What's it like
26:53
to intubate a bird? What, what's different about
26:55
it? They're well, they're easy. So birds and
26:59
reptiles generally, their glottis is pretty easily
27:03
visible. And so it's way easier than any primate
27:07
or way easier than a person. What's the most
27:11
challenging animal to intubate? I imagine there's
27:14
probably a few. Yeah, I would say like the mega
27:17
vertebrates are because you can't see and everything's
27:20
by feel. um you know you might be up to your
27:24
shoulder and something's mouth trying to feel
27:25
for the glottis to then pass a tube in and the
27:28
tube's like bigger around than your arm so um
27:31
that's always fun i can show you after we chat
27:34
i can show you some of the tubes that we use
27:35
i would love to see some giant endotracheal tubes
27:39
that sounds awesome yeah we use everything from
27:41
like We'll use like a 24 or 22 gauge catheter
27:45
for some, like made into an endotracheal tube,
27:48
like an IV catheter for some of our really small
27:51
patients, like small lizards or snakes or things
27:54
like that, all the way up to the endotracheal
27:57
tubes for elephants are, yeah, as big around
27:59
as my forearm. Oh, wow. Or bigger. So we spend
28:04
all day in anesthesia trying to keep the patients
28:06
warm. Is it ever the opposite problem when you're
28:09
taking care of the penguins and such? Yes. Yeah,
28:13
actually, that's a good question. So we spend
28:15
a lot of our time trying to keep patients warm,
28:17
too. But even some of the mammals that stay warm
28:20
become hyperthermic because especially most of
28:24
our animals here at the zoo are really well trained.
28:26
And so they'll come up in position for hand injections
28:28
and they fall asleep. And there's not a lot of
28:32
excitement, but some of them aren't. And so those
28:34
guys you worry about hyperthermia. So you need
28:37
to make sure you're monitoring temps there. But
28:39
then a lot of our cold -weather penguins actually
28:42
become hyperthermic if they're not kept cool
28:44
under anesthesia. So we actually have cold -water
28:47
blankets and things that we sometimes use, and
28:49
we monitor their temperatures to make sure they're
28:51
not hyperthermic. So my understanding is very
28:56
limited of how bird respiration works, but I
29:01
understand that they have air sacs. That's a
29:02
little bit different. What does that mean practically
29:06
when you're trying to breathe for a bird? You
29:10
generally still use manual respirations just
29:15
like you do for a mammal. But one kind of cool
29:18
thing, I guess, is if they have an upper airway
29:21
obstruction, you can just put a tube into their
29:25
salomic air sac and then breathe them through
29:27
that way. while you're scoping or trying to get
29:31
an obstruction out like sometimes a seed hole
29:33
or something gets stuck so you can do that but
29:36
yeah you also have to be a little careful when
29:39
you're like restraining birds because they don't
29:41
have a diaphragm and their keel has to be able
29:43
to move out to expand their air sacs to move
29:46
air through their lungs so their lungs aren't
29:49
like ours where air goes in and then goes out
29:51
air actually moves all the way through them goes
29:53
through the air sac circulates and then goes
29:54
back out and so You can't compress their body.
29:59
They can't breathe then. I was reading something
30:02
about where you did regional limb perfusion on
30:05
a little blue penguin. Can you tell me about
30:07
that? Yeah, so we've actually had to do regional
30:10
limb perfusion on a bunch of different species.
30:12
But penguins have a really high incidence of
30:15
like pododermatitis. And one of our little blue
30:18
penguins actually came from another institution
30:20
a long time ago. And a long time being like four
30:24
years now. 40 years sure um but um she actually
30:29
had um osteomyelitis and so we were doing pretty
30:32
frequent regional lymph perfusions and so you
30:36
just put a tourniquet on catheterizer give like
30:39
amikacin or whichever antibiotic you're choosing
30:41
let it sit for about 20 minutes and then release
30:44
it and that way you can give the systemic a systemic
30:47
dose but keep it mostly localized to a small
30:51
area that's really interesting i i didn't know
30:54
that you were getting that in depth on one animal
30:59
that's really great yeah we have a pretty crazy
31:02
preventative health program here where every
31:05
animal in the zoo has a different is on a schedule
31:08
so um depending on like their risk factors for
31:11
anesthesia or where they're at training wise
31:14
um and what they're like what the species is
31:17
anywhere from one to three years every animal
31:20
in the zoo gets an exam blood work x -rays ultrasound
31:22
um if they're small enough a ct something you
31:26
know we we do all of our diagnostics anytime
31:29
when they're sedated so that we don't have to
31:31
sedate them as frequently and so we catch things
31:35
really early so we don't actually have a lot
31:37
of surprises which is nice that's great so when
31:42
i come to work I'm not working with patients
31:46
that I think are likely to or could kill me,
31:51
which is different from what you do. So let's
31:55
talk about if you have to anesthetize a tiger
31:58
or something like that. What is your theory of
32:03
mind when you're going to set that sort of thing
32:07
up? What do you have to think about? um, communication
32:10
is probably the biggest thing and just making
32:12
sure that everybody knows their role and like,
32:15
um, so we're very efficient. Um, luckily most
32:19
of our like super dangerous animals are trained
32:23
really well as, as well. And so, um, our tigers
32:27
will present their, their backsides for hand
32:29
injection. We'll sedate them. Um, they'll actually
32:32
let us get blood from their tail veins too. Our
32:34
technicians are really good at it. And so, um,
32:37
Sometimes we can have pre -anesthetic blood work
32:39
on them, which is really nice. Actually, all
32:41
of our big cats at the zoo. So we can check their
32:44
organ function before we anesthetize them most
32:47
of the time. But pretty much we give an injection
32:52
of induction drugs, which is usually a cocktail.
32:57
Oftentimes we use like ketamine, metatomidine,
32:59
or dexmetatomidine, butorphanol, midazolam, some
33:02
combo. Sometimes we also have to use ultrapotents
33:06
like etorophen or carfentanil or something like
33:08
that. But then once they're sleeping, one of
33:11
the veterinarians will go in and just assess
33:14
anesthetic depth. And they're usually like sleepy
33:18
enough that they're not going to get up and try
33:20
to get you. And so sometimes they need a little
33:24
more as a top off or sometimes they'll give propofol
33:27
or alfaxan or something. Get them a little sleepier
33:32
and then we'll intubate them and maintain them
33:34
on gas. And so we just really monitor their anesthetic
33:38
depth. There's always someone that's committed
33:40
to that being their only responsibility is to
33:42
make sure that they're under a safe anesthetic
33:45
plane that's safe for them. And also they're
33:46
not going to wake up and hurt anyone. Right.
33:48
I remember that being something that was definitely
33:54
on my mind when I was taking care of the two
33:57
gorillas that I've had the opportunity to take
33:58
care of was. The safety of everything. And I
34:01
did feel safe the whole time, but my own nervous
34:06
system was certainly on high alert when I was
34:09
transporting a gorilla in a van and masking with
34:14
isoflurane. Yeah, that's probably the transport
34:18
from their habitat to the hospital and then back
34:22
from the hospital back to their habitats. Probably
34:26
the most risky time. probably initial transports
34:31
the most risky because if they're being carried
34:33
and jostled around sometimes they get stimulated
34:35
but we do things like like for our apes we wrap
34:39
their hands so that if they do become light under
34:42
anesthesia they can't grab onto anything usually
34:45
we have catheters placed or at least a mask with
34:48
anesthesia so that we can get them deeper if
34:52
needed but we usually have We often have people
34:58
from our public safety team escorting us so that
35:02
if there was an emergency, they could respond
35:04
quickly. But we're just really careful. Obviously,
35:10
human health and safety comes before anything
35:12
else. And that's kind of how it is across the
35:15
zoo as a whole. Like the human health and human
35:18
safety has to come before animal health. And
35:20
then that comes before any kind of property damage
35:22
or anything. So it's always humans, animals,
35:25
then property. I do something sort of similar
35:29
with some of my human patients. When people have
35:33
really long fingernails, I will sometimes wrap
35:37
their hands in a blue towel and wrap tape around
35:39
them as they're waking up so they can't scratch
35:42
their eyes and prevent corneal abrasions and
35:45
stuff. Oh, I never thought about that. I normally
35:47
thought, well, I guess I don't have long fingernails,
35:49
so I guess I wouldn't have to worry too much
35:51
about doing it to myself. So I've never woke
35:53
up with my hands wrapped, but I'd be like, what
35:56
did I do? It's usually for those really long,
35:58
sometimes very sharp fake nails that you have
36:01
to worry about. I call it kitten mittens. Oh,
36:03
yeah, that makes sense. Yeah, things you learn.
36:07
So there's other types of animals that can be
36:10
very dangerous too for different reasons. Can
36:12
you talk about super venomous snakes and what?
36:15
that's like yeah so because i've had reptiles
36:18
my whole life um there were points in my life
36:22
where i've kept a lot of venomous um snakes and
36:24
i don't anymore because um i feel like it's probably
36:29
not the best plan for me but um so i'm very comfortable
36:32
with them i don't think that my heart rate increases
36:34
at all if i'm working with a cobra or something
36:37
but our reptile keepers are really really skilled
36:41
and They'll use like hooks and things and get
36:45
them into an acrylic tube so that they can't
36:47
bite anyone. And then we'll use injectable anesthetics
36:50
to get them sleeping if we need to do a surgery
36:52
or something like that. And then we will intubate
36:54
them. You don't put your fingers in their mouth
36:57
to intubate them. You just always use tools.
37:00
And then once the tube's in, we'll tape their
37:02
mouth shut over the endotracheal tube. So then
37:05
it's not likely someone's going to be bitten.
37:09
Wow. i've read that reptiles can take a lot longer
37:15
to wake up than people what's what's the differential
37:17
between wake up times between different species
37:20
how does that work oh yeah that's a good question
37:23
so birds generally wake up really really quickly
37:25
um i should say before that and we oftentimes
37:29
use reversible anesthetic protocols because we
37:32
want our animals to be able to recover pretty
37:34
quickly sure um so birds wake up very fast um
37:39
oftentimes From the time when they're off of
37:42
an anesthetic gas till the time they're awake
37:45
and standing in mostly normal is a matter of
37:48
a couple minutes. It's really, really quick.
37:52
And then I would say some of our like higher
37:54
metabolism mammals wake up pretty quickly as
37:57
well. Within after reversal, usually it's like
38:01
five to 10 minutes and they're like getting towards
38:04
normal. Um, our reptiles, a quick wake up is
38:08
like an hour, um, and a prolonged wake up could
38:12
be 12 hours. And so it depends a lot on what
38:16
anesthetic protocols were used and, um, whether
38:19
reversals are available or things like that.
38:21
Um, there are reports actually of reptiles being
38:25
given high doses of ketamine or, um, uh, telazole,
38:30
which is teletamine and zolazepam. Um, previous
38:34
to some of the newer cocktails where they were
38:36
given pretty high doses to get them sleepy enough
38:38
to do a procedure and sometimes those animals
38:42
would sleep for like two to three days as long
38:47
as they're like breathing on their own and you
38:49
can maintain their their temperatures and stuff
38:51
that was like you know 15 years ago a lot of
38:54
them and they would still live and do fine it's
38:57
just really nerve -wracking i never really had
39:00
any that lasted that long but they are reported
39:03
Spontaneous ventilation, obviously a really important
39:07
piece for a lot of your animals, I would think.
39:10
Do you use neuromuscular blockers in any of your
39:14
veterinary anesthetics? We don't often. The only
39:18
procedures that I've been in where that's been
39:21
used has been for more invasive procedures in
39:25
our pinnipeds in a previous zoo. So they would
39:29
be on a ventilator sometimes. But here we generally
39:32
don't need to. And it's a little bit interesting,
39:36
too, because we talked about differences in recovery
39:38
times. But things like what the stimulus to breathe
39:42
is, you know, for mammals, a high CO2 makes you
39:45
spontaneously breathe. But for reptiles, low
39:48
oxygen is the stimulus for breathing. And so
39:51
when you have them intubated and they're receiving
39:54
100 percent oxygen, once they get to like a.
39:58
reasonable surgical plane of anesthesia, they
40:01
stop breathing. And so those guys always require
40:04
manual ventilation throughout a surgery if they're
40:08
actually at an appropriate level of anesthetic.
40:11
Can you forgive my ignorance and I'll ask you
40:15
what a pinniped is? Oh, sorry. Yeah, those are
40:18
like seals and sea lions. Oh, okay. I gotcha.
40:21
One of the things that I am very used to is putting
40:25
on anesthetic monitors and they're pretty standard
40:28
across human anesthesia, but I imagine it's completely
40:31
different in all of the different species that
40:34
you anesthetize. What are some of the different
40:38
types of monitoring that you do? Is there anything
40:41
that we would recognize in human terms? Yeah,
40:45
I think mostly we use all the same things that
40:48
you guys do. We monitor like SpO2 and EtCO2 and...
40:53
blood pressure and heart rate, respiratory rate,
40:56
temperature, EKGs. How we get those are sometimes
41:00
a little bit different. And positioning for an
41:04
EKG on a snake might be a little bit different
41:06
than for a person. How do you position an EKG
41:09
on a snake? You essentially pretend they have
41:12
legs. And sometimes the clips will work. Sometimes
41:20
stick -on leads will work. But oftentimes we
41:25
use a needle through their skin and then connect
41:28
the clips to the needle. So essentially you're
41:32
just pretending that the needle's a leg or an
41:34
arm. And how would you measure SpO2, for example?
41:39
Where would it go? So that depends a lot on the
41:43
species. But a lot of our animals, we put it
41:46
on their tongues, sometimes a finger, sometimes
41:49
a prepuce. Sometimes a vulva, like sometimes
41:53
you have to be a little inappropriate where you're
41:55
putting the probe. But sometimes there's rectal
41:58
probes that that work pretty well. It just it
42:02
really depends. You can put it like between the
42:05
mandibles on a beak on some birds like that connective
42:08
tissue. Sometimes that'll pick up a SpO2 pretty
42:11
well. Wow. I have put SpO2 probes in some interesting
42:16
places, but not necessarily. I've done the nose
42:22
and the lip and the ear and in addition to, of
42:25
course, the digits. But that's really interesting.
42:30
Yeah, we use nose sometimes too and lips and
42:33
ears and sometimes fingers. And it just depends
42:36
on the individual. So another thing that's a
42:40
little bit easier to monitor in humans is when
42:42
they wake up, they can tell you if they're hurting
42:44
or not. How do you monitor that in? your animals
42:47
how can you tell some animals will actually um
42:51
like there's a huge range right so so some animals
42:55
will will actually pay specific attention to
42:57
an area some will just favor it um even some
43:01
like reptiles where pain is still i mean there
43:05
are still people out there that don't think reptiles
43:07
feel pain which is absolute crap but um but They
43:13
just express it differently. So a snake, if it's
43:17
painful along an incision, when it crawls, it
43:19
might just pull weight off of it or kind of shift
43:22
their position a little so they're not crawling
43:24
on that site. A lot of our animals just hunker
43:27
down, and if they're uncomfortable, just are
43:31
less active, and so that's a thing. There's grimace
43:33
scales, so you can see facial expression on different
43:36
animals sometimes. Keepers really monitor their
43:39
behaviors. eating there's a lot of different
43:44
symptoms or signs but how are you treating something
43:48
like post -operative pain in a fish versus a
43:52
gorilla is it what are you how does that work
43:56
it's really variable so um yeah so like The just
44:02
pharmacokinetics of the different drugs are so
44:05
different. We do use a lot of things like a lot
44:07
of NSAIDs and a lot of opioids, and we use like
44:09
gabapentin and amantadine and things like that
44:12
as well. But like a good example would be, you
44:16
know, for most of our mammals, a hydromorphone
44:21
dose is like 0 .1, sometimes up to 0 .2 milligrams
44:24
per kilogram, something like that. For reptiles.
44:29
In general, the dose is one milligram per kilogram.
44:33
And then there's differences like oftentimes
44:36
people will say, well, what drug do you like
44:39
for reptiles? That's like saying what drug do
44:41
you like for mammals? Sure. So like an elephant
44:44
and a human are as closely related as, you know,
44:48
like a snake and a tortoise. So that's probably
44:54
not exactly true if you look at the like tree,
44:57
but. same right idea like there's a huge difference
45:01
between all the different species just because
45:04
they have scales doesn't mean that they're you
45:07
can treat them with the same drugs how much of
45:11
what you do is veterinary medicine that is known
45:17
and published about versus we're just going to
45:20
try this maybe nobody has done this before Um,
45:24
oftentimes it's something that's known in another
45:27
species. So we, um, there's a ton of data out
45:31
there on domestics and, and on production animals
45:34
and things like that. Sure. And so, um, and there's
45:37
the, the body of literature and zoo medicine
45:40
is rapidly growing. And so we're constantly learning
45:44
new things, which is amazing. helps lets us contribute
45:47
as well which is a good great feeling it's one
45:50
of the things i love about my job here is like
45:51
i can feel like we make a difference outside
45:53
of the you know the zoo proper um but um i would
45:58
say like like a fair number of the things that
46:02
we do are are um known in other species and then
46:07
we have to extrapolate yeah that makes sense
46:10
so i imagine that there's some times where you
46:13
decide to not do an anesthetic that it might
46:17
be too risky. Um, can you talk about those situations
46:21
and what your thought process is around the ethics
46:25
of what to do and those types of situations?
46:28
Yeah. Um, in general, everything is a risk assessment.
46:34
So every, every procedure, you know, it's like,
46:37
is, is the benefit of doing this outweigh the,
46:41
is it going to outweigh the risk of this procedure?
46:43
And so we have as, as different as this is, you
46:49
know, in human medicine, you know, euthanasia
46:52
is not an option. Right. And so at least not
46:55
here. And so for our animals, if, if something
47:00
is sick enough that they're, you know, we're
47:04
worried that they're suffering or that they're
47:06
not going to improve. we can do things like plan
47:09
an anesthetic procedure to see if there's something
47:13
that we could make a diagnosis that could fix
47:15
the problem or if they need a surgery that we
47:18
could fix it. But while they're under anesthesia,
47:21
if we find that there's something we can't fix,
47:24
we can opt for euthanasia. And so if you find
47:28
metastatic tumors and it's not an animal that's
47:31
amenable for chemotherapy or something like that,
47:33
we could opt for euthanasia so that they don't
47:35
have to suffer. So we don't usually shy away
47:39
from the risks of anesthesia in those situations
47:41
where the candidate's not great because if they're
47:44
not a great anesthetic candidate because they're
47:47
sick, that means that there's something significant
47:50
that we should try to address so that their quality
47:52
of life isn't impacted. Yeah, that makes sense.
47:56
So let's say one of our residents was really
48:00
interested in getting more involved with the
48:03
zoo and getting more involved in this sort of
48:05
anesthesia. what would you recommend that they
48:08
do um just get involved with the program with
48:11
our apes um it's it's kind of a weird like veterinary
48:16
medicine has progressed a lot and so there's
48:18
a lot of specialty veterinarians and so based
48:23
on our practice act you know we're supposed to
48:25
involve veterinary specialists whenever appropriate
48:29
and so we don't usually have human anesthesiologists
48:35
come for procedures on animals that are more
48:38
similar to something that would be seen in veterinary
48:42
medicine. But I would argue that there are some
48:47
veterinary anesthesiologists that have done a
48:49
ton of ape work. They're kind of few and far
48:53
between. So like you guys anesthetize, in quotes,
48:57
apes every day. And so you're very... very knowledgeable
49:01
you know all the newest things in and so we're
49:05
really comfortable working with you guys for
49:06
those those cases because you're you know more
49:10
skilled in it than most of the other people that
49:12
we could find yeah we really appreciate it well
49:15
we really appreciate the opportunity it's it's
49:17
something that i consider one of the top experiences
49:20
of my life was getting to take care of the gorillas
49:23
here honestly yeah it's cool I've found myself
49:28
more involved in like human, like public health,
49:31
one health kind of dimension a little bit. And
49:33
so it's probably similar. I think that stuff's
49:36
really interesting how human, like the human
49:39
population is kind of monitored and screened
49:43
and like public health things. And so it's probably
49:46
similar. I think it's really interesting to me
49:48
doing that because it's kind of outside of the
49:50
things I do every day. And, you know, you guys
49:52
aren't anesthetizing bonobos or gorillas every
49:54
day. Yeah, right. before i let you go i'd like
49:57
to ask you about your own personal style points
50:00
what what style points or points of personal
50:02
preference have brought you success both in and
50:05
out of the operating room that's another thing
50:07
where i think communication is you can't really
50:11
overstate the importance of communication so
50:14
i like to goof around i like to have fun i don't
50:18
i don't like to just be serious all the time
50:21
i'm serious when i need to be serious but i think
50:24
having you know we're all dealing with you know
50:27
critical patients and complicated situations
50:30
and things and so just have being lighthearted
50:33
and having like a great relationship and open
50:36
communication with your team is probably more
50:39
important than any knowledge you could ever gain
50:41
you can always find someone that's more intelligent
50:44
than you right but you need to be able to communicate
50:47
with that person if you want to get a good outcome
50:49
so i do think that above all else like Being
50:52
able to work as a team and communicate effectively
50:55
makes for better procedures. Mike, thank you
50:58
so much for joining us. I really appreciated
50:59
your time. Yeah, it was a good time. Thanks for
51:03
listening to another episode of Style Points.
51:06
To address the elephant in the room, the picture
51:08
associated with this episode is of Mike and I
51:10
posing with an elephant -sized endotracheal tube,
51:13
size 45 if you're curious, a little bit bigger
51:17
than the 7 .5 we use in the adult human population.
51:21
If you enjoyed the show, please consider leaving
51:23
us a five -star rating or a written review. It
51:26
really is the best way to help other people find
51:28
the podcast. You can always reach me at stylepointspodcast
51:32
at gmail .com. Take a deep breath. Open your
51:36
eyes. We're all done.