by Dawn Brazell
Public Relations
The parents he
meets know him as their child's
anesthesiologist at MUSC Children's
Hospital. Others may recognize him from
TV and print ad campaigns where he's
dressed in a monkey towel blowing
bubbles with children.
Dr. Frank
McGowan as seen on commercials that ran
promoting MUSC's Children's Hospital.
But there's yet another side to Frank
McGowan, M.D., who collaborates with
researchers at Boston Children's
Hospital in Massachusetts on a new
technique heralded as a potential
medical breakthrough. The team has
developed microparticle-based
oxygen-delivery technology that
oxygenates the blood and bypasses the
lungs. It has the potential of saving
lives for a wide array of patients and
conditions, from wounded veterans in the
field to premature babies in intensive
care units.
The research landed on the cover of the
December issue of Scientific American as
one of 10 "world changing ideas." It
also was the cover of the journal
Science Translational Medicine in June
2012 with its successful use in an
animal model. McGowan said the
possibilities of promising clinical
applications will keep researchers busy
for many years to come.
Dr. Frank
McGowan holds up the December issue of
Scientific American that selected the
research he and Boston colleagues are
doing as a world-changing idea.
The idea first came up five years ago
when McGowan worked at Boston Children's
Hospital. A doctor in residence, John
Kheir, M.D., asked how he could have
saved a patient he lost because of an
inability to quickly oxygenate her
blood. "We started thinking why don't we
have better ways to acutely deal with
this while we're trying to figure out
what we're going to do longer term."
Then Kheir and McGowan began to do more
than talk.
The challenge was to devise some kind of
shell to safely encase and deliver
oxygen in the blood so that it could
release the encapsulated oxygen to
deoxygenated blood and then collapse in
a non-toxic form to be eliminated from
the body.
"We found that there are materials that
can do that with shells made of lipid or
mixtures of fats and other substances,
many of which are normally found in the
body," McGowan said. "We found a number
of really smart people who had spent
their lives trying to figure out how to
encase various substances, biologic
drugs, viruses, genes and other things
in lipids and other compounds. There's
always a whole world out there when you
go looking."
McGowan said the research is the perfect
example of why basic science research is
needed. "There was a tipping point.
People had devoted careers doing
fundamental work in related areas for
many reasons and applications. We were
able to study and theorize based upon
it. If we had to start completely from
scratch, we would have had to have spent
five careers trying to do this."
Another advantage of having
physician-scientists collaborate with
basic scientists is that the former
could understand and take advantage of
the basic research and apply it to solve
a clinical problem. Part of this was
having the knowledge to construct the
right paradigms and develop effective
experimental models, he said. "It's
these interactions with people of widely
disparate backgrounds and experiences
that produce the best results
sometimes."
That's not to say it was easy.
McGowan said they had many failures
until about three years ago when their
persistence started to pay off. McGowan
recalled finishing a case in the
operating room and deciding it was time
to test the latest shell version. They
drew some of his blood and made it
hypoxic, turning it dark red. When they
injected the substance, his blood turned
pink. It was a turning point. They then
had a number of things to test,
including defining the chemical and
biologic characteristics of the
microparticles' shells before designing
an animal model to test the further
refined foam suspension.
The suspension contains lipid-based
microparticles, smaller than what would
block the body's tiniest capillaries,
that encapsulate a core of pure oxygen
gas that can be delivered via
intravenous injection. Once the shell
delivers oxygen, it collapses to
sub-micron size and is eliminated by
normal body processes. The amount of
lipid delivered is consistent with what
can be tolerated in other medical
applications, he said.
McGowan said the ability to administer
oxygen and other gases directly to the
bloodstream may represent a technique
for short-term rescue of profoundly
hypoxemic patients, to selectively
augment oxygen delivery to at-risk
patients or organs, or for novel
diagnostic techniques. They will need
further research to prove the lipid
delivery system is safe and to find the
optimum chemical formulation and
delivery method.
One of the main advantages he foresees
for clinical use is that it can buy time
in situations with acute airway loss.
"We'd be able to
buy five or 10 minutes with someone who
could pull up with a cart and inject you
with oxygen as we are preparing more
definitive, longer-term therapy to
restore your ability to oxygenate."
It will be five to 10 years before the
research is ready for clinical
applications, but a sampling of other
possible uses that may prove successful
are:
- a bridge to
ECMO (extracorporeal membrane
oxygenation) or endotracheal
intubation;
- short-term
treatment by paramedics and emergency
room physicians for those with airway
loss until they can be stabilized;
- delivering
oxygen intravenously may allow reduced
mechanical ventilation in patients
with various kinds of lung disease,
perhaps reducing ventilator-related
lung injury;
- as a treatment
for diabetic wounds (either topically
or intravenously), which are
notoriously hard to heal
- lower dosages
for patients who only need partial
oxygen replacement as might occur in
situations such as lung injury or
heart disease;
- for use in
the battlefield for paramedics
treating extreme blood loss or to
improve the outcome of
cardiopulmonary resuscitation (CPR).
"The toughest nut of
all to crack and the one that is among the
most interesting is the lower level,
longer duration-needed application – the
lung injury patient, or the cyanotic
(blue) baby situation. Clinically, these
may be some of the better applications,
but experimentally, they're also some of
the toughest models."
McGowan compares doing
the research with his Boston and MUSC
colleagues as similar to playing a team
sport at a high level. It's constantly
challenging and stimulating.
"I'm certain that I'm
better clinically because of what we're
doing in the lab, and I also think that
I'm better in the lab because of what I do
clinically. It really does inform in both
directions."
Though he doesn't know
what applications might pan out, McGowan
said it's worth all the extra work. He
apologizes for tearing up as he explains
what motivates him to do translational
research.
"Parents hand me their
child every day to take into the operating
room. I still don't know how they have the
courage to do it. I usually have about 10
minutes to meet them and convince them to
allow me to take care of their child. To
continually try to be worthy of that trust
and improve the outcome of what we do are
the best parts of this."
Friday, Feb.
1, 2013
|