Occupational hazards for cath lab operators pose health risks over the long term.
Since the incorporation of fluoroscopy in the cath lab 50 years ago,
health risks associated with radiation exposure have been of increasing concern
to those who make their living in the lab.
During that time, developments in technology have offset some of these
concerns by affording cath lab operators the ability to perform a
catheterization with decreased amounts of radiation required to obtain good
“The framing rates to visualize images 30 to 40 years ago used to
be 30 to 60 frames per second, and now we routinely use 15 — the
fluoroscopy during that time was continuous, but now it is pulsed at 7.5 frames
per second, so you are shooting fewer frames,” said Thomas Bashore,
MD, clinical chief, division of cardiology, Duke University Medical Center,
Durham, N.C., in an interview. “The equipment is also a lot better and
provides higher resolution images.”
Nevertheless, increasing demands for catheterizations and extended times
in the cath lab have countered the benefits interventionalists experience as a
result of these innovations.
“Thirty years ago, we performed a fewer number of cases per day,
the cases were generally shorter and the total fluoroscopy times were
relatively brief. Now, a busy operator performs six to 10 cases per day,
including complex interventions requiring prolonged fluoroscopy
exposures,” said James A. Goldstein, MD, director of cardiovascular
research and education, William Beaumont Hospital, Royal Oak, Mich., and a
founding member of the Multispecialty Occupational Health Group.
Augmenting the concern of overexposure to radiation are the known risks
associated with wearing orthopedically burdensome leaded aprons over the long
However, despite these safety hazards and the innovations to the imaging
modalities themselves, the radiation protection systems have remained virtually
unchanged during the past 3 decades.
“We are still using leaded aprons, glasses and thyroid collars, and
small shields we put up from the table or drop down from the ceiling;
unfortunately, our heads, arms and legs are incompletely protected,”
Goldstein said. “Little has changed in radiation protection, which is
The Nature of the Problem
Occupational health hazards in interventional cardiology have often been
referred to as “the cost of doing business” by those who enter the
field. For Bashore, this lack of attentiveness to a potentially serious problem
can at least be partially explained by the fact that, unlike radiologists,
cardiologists do not receive a lot of training in radiation safety.
“Education in radiation safety for radiologists has really helped
them understand how much radiation the operators and patients receive.
Cardiology has not done a good job with this,” Bashore said.
According to Bashore, most cardiologists have not paid a lot of
attention to radiation exposure, “mainly because they have not been
focused on the equipment itself but rather on the procedure. Radiologists are
much more focused on the actual equipment and how it is best used. It’s
only been in the last decade that people in cardiology have started to realize
they need to pay more attention to this.”
Part of this realization in recent years has come from research that has
highlighted the potential harm of long-term, cumulative radiation exposure.
Recently, a study was published in EuroIntervention that brought one of
the chief concerns to the forefront.
In the study, Ariel Roguin, MD, PhD, and colleagues performed an
extensive literature search and reported that, among interventional
cardiologists, there were nine cases of brain tumors, five that were already
published and four new cases. Since the publication, Roguin, who is associate
professor at the Technion, Israel Institute of Technology, Haifa, Israel, has
regularly received emails of additional cases of malignancies among those in
the specialty, which now number at 20.
Although admitting that the collection of cases via email is not
scientific, Roguin insisted that interventional cardiologists must be aware of
the potential dangers of radiation exposure, even though the risks most likely
will never be proved because of the low numbers of epidemiological issues and
“I can’t prove that our findings are anything more than
background noise. However, from those 20 cases we have, I know the side that
was involved in 12. In those 12, one was from the right side, one was from the
midline and 10 were from the left side, and we work with radiation to our
left,” Roguin said. “So is this chance? Maybe. I’m still
actively seeking more cases and plan on updating our small data set in the
Despite there not being a “smoking gun” yet in terms of
whether there is an actual risk for cancer among those who work in the cath
lab, Goldstein, who is also a member of the Cardiology Today
Intervention Editorial Board, said the issue of cancer in the cath lab is a
“These anecdotal reports of cancer among
interventionalists are growing in number,” he said. “But caution must
be exercised when interpreting such data. In order to draw firm conclusions,
further studies where we really know what the numerator and denominator are
will be necessary. Thus, as a scientist, one must look upon such anecdotal
cases with a healthy dose of skepticism; however, one cannot ignore the warning
such cases are sending.”
John W. Hirshfeld, MD, professor of medicine at the Hospital of
the University of Pennsylvania, Philadelphia, agreed that the quality of data
currently available is not strong, stressing that there have not been good
observational data on whether practitioners have a detectable degree of health
effects from their exposure.
“The field of intervention is just starting to accumulate people
who have 25 to 35 years of experience, so we don’t really know the health
effects of long-term exposure in the cath lab yet,” Hirshfeld told
Cardiology Today Intervention. “There have been some armchair
analyses that have looked at what the estimated increased cancer risk is for
someone who is occupationally exposed to radiation, and the analyses suggest
that they probably have an incremental lifetime risk of about 2%. But your
lifetime risk of getting cancer anyway is around 20% to 25%, so the incremental
effect of occupational radiation exposure would be difficult to detect with
confidence in the small population of career catheterizers.”
For those who are occupationally exposed to radiation, the term ALARA,
or “as low as reasonably achievable,” has for decades been the
standard for acceptable exposure levels. However, the subjectivity of what is
“low” and what is “reasonably achievable” ultimately leads
to questions as to how best to apply this principle to practice.
In an attempt to bring more objective measures to radiation exposure,
badges are now worn by cath lab operators that collect day-to-day exposure
levels. And for those who exceed the monthly levels deemed safe, they are taken
out of the cath lab for the remainder of the month.
“Operators are essentially being punished for their exposure. So,
not surprisingly, many don’t wear a badge,” said Lloyd W. Klein,
MD, professor of medicine, Rush Medical College, Chicago, and a member of
the Multispecialty Occupational Health Group. “We’ve created a system
in which if you dare to be exposed you will be punished. That has to change or
no one will wear their badges.”
Rather than limiting exposure by compromising the operator’s
ability to perform their job, others are suggesting ways to fine-tune
methodology that will reduce radiation exposure and the resulting consequences.
In an editorial published in the American Heart Journal, Bashore offered
several recommendations on how to reduce radiation exposure in the cath lab,
- Use fewest magnified views.
- Keep source-to-image distance as narrow as possible.
- Keep the maximal kilovolt potential across the tube as high as
practical for good contrast, but keep milliamperes as low as possible to reduce
the number of X-rays produced.
- Keep the number of exposures to a minimum.
- Use pulsed fluoroscopy.
- Use lowest framing rate possible.
Although the editorial was published 8 years ago, Bashore said these
measures are still pertinent to the practice of interventional cardiology
today; however, he added that minimizing time in the room, limiting high-dose
fluoroscopy and avoiding extremely angulated views to keep the source-to-image
distance narrow are important as well. Added to which, awareness of dose to the
patient, he said, can be determined in most laboratories by noting the
dose-area-product (total amount of exposure sent to the patient) and an
estimate of skin dose that can be derived from the interventional reference
In addition, Hirshfeld suggested that operators make sure the equipment
is properly calibrated so that it is using the lowest possible dose rate that
will produce quality images, and operators be as far from the X-ray tube as
possible. “The X-ray intensity goes down as the square of your distance
from the source, so if you double your distance from the source, you’ve
just decreased your exposure by a factor of four,” he said. “Also, it
is important to use the ceiling mounted Plexiglas shields, which stop 90% of
the scattered radiation. By using it, you cut the dose rate to the upper body,
which is where most of your unprotected structures are, by a factor of 10. Just
about all laboratories have them installed, but the operator has to decide to
Hirshfeld also said the exposure levels for the clinical staff who work
in the lab should be minimal.
“Physicians who work in the cath lab need to make sure that staff
members are minimally exposed and that they keep their distance from the X-ray
source, because most of the time the staff should not have to experience the
exposure,” he said. “The physicians can’t get out of where they
stand, but nurses and technicians can.”
An ‘Epidemic’ in the Cath Lab
Although techniques and protocols to lower exposure levels have been
evolving, surprisingly, radiation protection technologies have been virtually
unchanged during the past 30 years. And, unlike the anecdotal reports of harm
caused by radiation exposure in the cath lab, the health risks associated with
wearing leaded aprons and collars over the long-term are clinically
substantiated — to the extent that some are calling it an epidemic.
“It has been well-established that working in the cath lab for 20
or more years and having to work standing up and wearing heavy leaded aprons is
associated with an epidemic of orthopedic problems, particularly in the spine
but also in the hip, knees and ankles,” Goldstein said. “Almost
everyone I know — even our younger colleagues — walk out of the cath
lab at the end of a busy day with an aching back.”
To quantify this epidemic, Goldstein, Klein and several others from the
Interventional Committee of the Society of Cardiovascular Angiography and
Interventions conducted a survey of more than 1,600 members and received
responses from 424. Among those who responded, orthopedic problems were
prevalent, with 42% experiencing spine problems — of which 70% were
lumbosacral and 30% cervical — and 28% experiencing hip, knee and ankle
“Because of these orthopedic problems, there has been a large
percentage of cath lab operators who miss work or even change careers,”
Klein said. “To be direct about this, hospitals don’t really expect
people to spend their whole careers in the cath lab. They expect radiation
technologists and nursing staff and physicians to retire in their 50s and go on
and do more general medicine. They just keep producing new and younger
radiologists and technicians, while the older ones go out and become sales
reps, head nurses, chiefs of cardiology and so on. It really wasn’t until
the interventional era of the last 5 to 10 years that a large number of people
are truly spending their careers being an interventional cardiologist and
retiring as one.”
This can partly explain why there has been little change in lab design
over the decades, Klein said, although he added that three additional factors
are also at fault:
“First, those who operate the labs don’t mind if there is
periodic turnover because it keeps cost down. Second, those who work in the lab
are constantly new and don’t think hazards will happen to them. And third,
those who have experience suggest that anyone who is concerned about these
problems shouldn’t work there.
“So, when one takes a complete look at how the cath lab is run,
it’s fair to say that if we ran mines or factories like this, we’d
all be in jail,” he said.
A Call for Change
Due to the multifaceted concerns of working in the cath lab, many
interventional cardiologists are calling for a complete revolutionizing of the
current work environment in favor of a more technologically advanced,
One way that some propose would limit occupational radiation exposure in
the future is robotic-assisted PCI. This technology would potentially allow the
operator to direct the movement of catheters and wires while standing several
meters away from the patient and the source of radiation.
In a 2011 study, Klein, Goldstein and other members from the
Multispecialty Occupational Health Group forecasted the cath lab of the future,
and highlighted robotic-assisted PCI as one of the possible game-changers.
“Robotics would be the ultimate answer if it works,” Klein
said. “However, I don’t expect that the transformation to
robotic-assisted PCI will happen in my lifetime. People don’t want to go
under the knife in the first place, and if they’re going to go under the
knife they want the knife to be in the hand of a human being that they select;
and as long as that attitude exists, we’re not going to get into
There are also some more fundamental issues that must be addressed as
“Robotic-assisted PCI is not very practical right now. There are
little data supporting its use and the techniques to use it effectively still
need to be worked out,” Hirshfeld said.
Consequently, some are advocating for measures that have the potential
to improve working conditions in the short term. However, those too are not
without their set of challenges to overcome.
“Ultimately, you have to get the lead off the shoulders and backs
and get it within the room so that it is protecting everyone,” Klein said.
“But in order to do that we have to make manufacturers change their
According to Goldstein, during the past 5 years, the Multispecialty
Occupational Health Group has met with industry, including the major companies
that manufacture X-ray systems, with the intent of convincing them to do just
that. “We communicated to them that the present environment is
unacceptable, and that it’s time for industry to change it.”
Although the large amount of capital required to develop new cath lab
technology has shown to be a significant obstacle, the challenge is further
compounded by the fact that change must also reach the hospital level as well.
“Hospitals have to be willing to spend [the money],” Klein
said. “Unfortunately, it’s much easier for them to replace doctors
who get orthopedic problems than to spend the money.”
Although this may have been the economically correct answer up until
recently, the number of procedures being performed currently and the amount of
training and experience it takes to do them effectively and efficiently
indicates that operators’ careers are not going to be 15 to 20 years long
but rather 30 to 40 years long, Klein said.
“Suddenly, we’re no longer moveable parts and replaceable
pieces. Now, once you train a nurse to work the equipment in the lab and
assist, it’s not so easy or cheap to replace them, and as a result the
finances and economic decisions change. It won’t be economically feasible
to just treat people like they have a limited career,” he said.
Yet, one important change that has taken place, which has the potential
to lead to future improvement in working conditions, is the transition away
from the mindset that a hazardous work environment is just part of “doing
“Surely we can create a better environment. That is what the
Multispecialty Occupational Health Group is working toward,” Goldstein
said. “The societies and their members need to advocate to industry, and
subsequently hospitals, the need for better solutions and a safer place to
work.” – by Brian Ellis
Bashore TM. Am Heart J. 2004;147:375-378.
Goldstein JA. Catheter Cardiovasc Interv.
Hirshfeld JW. Circ Cardiovasc Interv.
Klein LW. Cath Cardiovasc Interv.
Klein LW. Cath Cardiovasc Interv.
Roguin A. EuroIntervention. 2012;7:1081-1086.
Disclosure: Drs. Bashore, Hirshfeld, Klein and
Roguin report no relevant financial disclosures; Dr. Goldstein has equity in
Eco Cath Lab Systems, a company designing novel radiation shielding products
that are not yet available.