When new technology, science
or engineering appear in
medical devices, how does
FDA assess their safety and
effectiveness?
When existing
devices malfunction,
how does FDA verify the
root cause of the problem?
Scientists and engineers in
FDA laboratories are asking
these questions and finding
the answers that help assure
that the latest technology
in medical devices is safe
and effective for patients.
In 2009, a patient underwent
routine gastric band
surgery, a widely done
procedure designed to help
severely overweight people
achieve weight loss.
The surgery went well,
but a few weeks later,
the band began to leak.
Then the same problem
occurred with another
patient.
What was the problem?
And, was it an
indication of a larger,
potentially more
dangerous problem?
Scientists at FDA's Office
of Science and Engineering
Laboratories, who look at
products before and after
they enter the market,
began to investigate.....
FDA has a special program
where we listen to the
clinical concerns of
health-care professionals
from across the country and
this is called the medical
product safety network.
Through that network, we had
a report about a problem
with a lap-band that
seemed to be leaking.
An adjustable gastric band,
frequently called a lap
band, is a device that's
used to treat obesity.
It's a collar that's
surgically placed around the
top of the stomach.
Then, using a needle that's
inserted into a port
implanted under the skin,
liquid fills the collar
squeezing the stomach.
This process works by making
patients feel full more
rapidly, so they eat less.
The hospital was very
concerned because they had
to repair several different
patients' lap bands and they
weren't quite sure
what the problem was.
...What they were noting at
this hospital was that the
lap band was leaking and
therefore, deflating.
We needed to understand
where in the path of flow
the leak was occurring.
And we didn't know how
widespread this was.
Was this a problem just at
this one hospital where we
had the report?
Was it a problem at many
different hospitals who
weren't thinking to
report it to us?"
So when you get an
initial report like this,
you really have many
different areas of concern.
We looked at the problem and
debated amongst ourselves,
is this an indicator of
a larger public health
problem?
And it felt like
it could be.
Therefore, we pulled
together a group of experts
from across the Center and
we talked about the issue,
and we called the hospital
together to find out what
they thought the
problem may be.
After some investigation
at the hospital site,
they determined that they
didn't think the problem was
with the lap band but rather
with the Huber needle that's
used to inject saline
into the lap-band.
Huber Needles have been
around since about 1946,
when the patent
was first issued.
They're designed so that
when the needle pierces a
rubber septum, there
is no hole left behind.
The hole, in a sense, heals
back up as the needle comes
out.
That's important if you're
trying to maintain sterility
or if you have a need for
multiple punctures through a
port with no leakage
after the fact.
Ports aren't just
used for lap bands.
Ports are used in many
different kinds of
procedures.
Most commonly, they're
placed under the skin for
chemotherapy purposes.
So many cancer patients who
are undergoing long-term
chemotherapy will have a
port placed under the skin,
and then when they go in
for their chemotherapy
treatment, a Huber needle,
with a chemotherapy agent,
is placed through the
skin into the port,
and goes into the
patient's system.
When a Huber Needle "cores",
it actually cuts a piece of
rubber out of the septum
that creates two potential
problems.
The first is that the
material that the port is
supposed to retain can leak
out and go places where it
should not.
The second concern is that
the foreign body could end
up in the bloodstream, which
then can be sent to the
heart, sent to the lungs and
sent to the brain - we just
weren't sure.
That was one of the major
reasons we wanted to go
ahead and further understand
the extent to which Huber
Needles do core, beyond
this one simple case.
We realized again that this
could be a problem well
beyond that with
just lap bands.
This could be a problem for
every patient undergoing
chemotherapy with the port.
So we brought the problem to
one of our scientists who
has a background in
mechanical engineering and
in manufacturing.
He investigated the Huber
Needles to determine if we
had a design problem or
a manufacturing problem.
The first question I asked
myself: how do we test the
needles with the lap band
port to see if they create
cores?
We needed to figure out how
to test their needles....
We looked for and discovered
that there was no standard
design parameter for testing
ports with different
needles.
So, we designed
our own test.
That was a major
part of our effort,
to come up with a test that
we could validate and then
we could share, so that
other people doing this sort
of work, the manufacturers,
our own internal
organizations, could
reliably reproduce the test
and believe the
data that they got.
We had to determine - was
this a problem with one
batch or lot of needles, or
was this a problem with all
of the needles
that were made?
So, we bought additional
needles from the same batch.
And we bought needles
from different lots.
When we tested Huber Needles
we were trying to follow
standard medical practices
which nurses use in
hospitals...
The lab invited me in to
demonstrate how the port and
needle are used in real
clinical practice on a
patient.
We used the same
size needles,
same type of needle and
the same size syringe.
I started to see obvious
differences in production of
these needles and I...was
not sure if this was a
design problem or a
manufacturing problem.
It appeared to be both
- a design issue and a
manufacturing issue.
The design issue was with
the back heel of the
needle's edge, where it was
actually cutting the septum
as it was entering the port.
The manufacturing issue was
that some designers had a
good design, but they
just couldn't produce it
consistently each
and every time.
When FDA reviewed
Huber Needles,
before this issue was
brought to our attention,
we were concerned with other
issues related to a medical
device review, such
as biocompatability,
consistency,
manufature--other issues
related to the performance
of the device.
Once we identified
the issue,
we brought to their
attention that coring was
also an important
consideration in the review
of Huber Needles.
We knew we had to take
immediate action to inform
the public of our findings
as well as to encourage
manufacturers to review
their manufacturing
operation and, if necessary,
perform a recall.
We met with 10 of the
largest manufacturers at FDA
headquarters.
FDA scientists presented
their test findings and the
Office of Compliance asked
for specific details about
how the firms would prevent
defective products from
getting on the market.
We also informed the firms
that we'd be following up
with non-compliant
manufacturers.
After this, we advised our
field offices on how to
inspect these
manufacturing facilities.
We also developed
safety communications,
such as letters to firms and
a website to notify users
and patients
about this issue.
In the end, a Huber needle
manufacturer conducted a
voluntary recall of more
than 2 million Huber
needles.
FDA's public health
responsibility spans the
entire life cycle
of medical devices,
from the early
development of a device,
to the manufacturing
of the device,
and then to its
use in the market.
At any stage of a
device's life cycle,
FDA makes well-supported
regulatory decisions based
on the information
available.
We call it the "total
product life cycle" and the
way this works in this
particular instance is that
one group received
the issue,
recognized that
it was a problem,
went to the group that would
do the investigation and
explore and find out what
actually was the problem.
Another group then was able
to take regulatory actions
that were needed to
improve the product at the
manufacturer level.
And the other group was then
able to communicate the
problem to all the hospitals
so they all would become
aware of the problem
with Huber needles.
This was an excellent
example of the various
elements within FDA working
together to solve a problem.
It involved publishing
our results.
And we're partnering with
industry to develop a
standardized test method so
all the needles can now be
tested the same way.
This new standard
is very significant,
because once it is
adopted by manufacturers,
it will serve to assure FDA
that the needles do not
core.
The testing procedures
that we developed and the
enforcement actions
that took place,
because of the results
that we uncovered,
now allow us to be
assured that industry,
going forward, either can
identify their own problems,
or can assure us that
they've now developed good
manufacturing processes to
ensure Huber Needles don't
core.
Signaling a public safety
concern....Identifying the
problem...Effective
communication...Working with
industry to adopt a
sustainable long-term
solution...
This is FDA at its most
effective...Achieving its
mission.
