It is widely assumed by vascular surgeons that amputation is the safer
option compared to infrainguinal bypass operations for high-risk patients with
multiple comorbidities. Neal Barshes, MD, MPH, contends that the health care
industry never had the data to precisely and fairly investigate that assumption
until now.
Researchers from the Division of Vascular and Endovascular Surgery at
the Brigham and Women’s Hospital in Boston, performed a risk-adjusted
comparison of early postoperative morbidity and mortality of high-risk patients
who have undergone infrainguinal bypass and major amputation.
The database of patients included 780 participants in the infrainguinal
bypass group and 792 patients in the major amputation group.
“The main finding of our study is that when we do an ‘apples
to apples’ comparison of high-risk patients undergoing amputation and high
risk patients undergoing bypass, the risk of death was actually lower in
patients undergoing bypass,” Barshes told O&P Business
News.
Infrainguial bypass had a lower 30-day postoperative mortality (6.5%)
than major amputation (10%).
“We interpret these findings as meaning that comorbidities —
such as unhealthy heart or kidney failure — should not, by themselves,
represent a reason to avoid attempting a bypass operation to improve
circulation and reduce the risk of ultimately needing an amputation.”
Barshes warned that this does not mean that an infrainguinal bypass
should be performed simply because it is associated with a lower risk of death.
In fact, infrainguinal bypass was associated with higher rates of return to the
operating room (27.6%) than amputation (14.1%) and a higher percentage of
bleeding requiring transfusion (2.1% vs. 0.9%).
Further, the study indicated that there was no difference in the overall
number of major adverse events or postoperative length of stay between the
infrainguinal bypass and major amputation groups.
Still, patients and practitioners must allow for other complicating
factors before any decision is finalized, Barshes recommended.
“These factors include whether they have an artery that can be used
as a ‘target’ for bypass (an artery past the area of blockage),
whether they have any veins in their legs or arms that can be used to perform
the bypass around the area of blockage and whether they are likely to be able
to walk after the bypass operation and derive benefit from the operation,”
Barshes said. “Not all high-risk patients are the same and there may be
certain patients with an extremely diseased heart, lung or kidney function that
would not be safe for a bypass operation.”
According to Barshes, bypass operations remain the most definitive and
reliable way of improving circulation to the leg, but he remains cautious.
“While the results of bypass in terms of saving a leg and avoiding
the need for amputation are good, the outcomes are not perfect,” he said.
“No bypass is as good as a healthy artery, so bypasses may stop working
over time — or even when working perfectly — may not improve
circulation enough to avoid the need for amputation.” — by Anthony
Calabro
This study addresses an ongoing controversy in vascular surgery; whether
amputation is actually safer than bypass surgery and is therefore the preferred
choice in high-risk patients with critical limb ischemia. The authors question
the long-held assumption that amputation is associated with a lower
perioperative risk of morbidity and mortality than bypass surgery for limb
salvage, presumably because the magnitude of the operation required is less.
While amputation is usually performed in less than an hour, lower
extremity bypass takes several hours and employs a much larger incision. The
results of this study show that patients undergoing infrainguinal bypass had
lower amputation rates than those undergoing major amputation, implying that
post-operative risk factors such as reduced mobility outweigh the increased
risk of the greater operation.
There is no free lunch, however — patients undergoing bypass had
significantly higher rates of non-fatal complications and there is no guarantee
of successful limb salvage even when bypass is undertaken.
This study reinforces the notion that the decision to bypass or amputate
should be based on the likelihood of successful bypass, rather than the
patient’s risk factors, although this perception is deeply entrenched
within the ranks of physicians and surgeons who care for patients with critical
limb ischemia and may be hard to alter.
— Cynthia K. Shortell, MD
Chief of vascular
surgery, Duke University
This data confirms previous data which suggests pretty strongly that
improving blood flow to the extremities is associated with less mortality in
patients and actually prolongs life. This study also confirms previous studies
data which suggests that while amputation is definitely the simpler option, it
is not always the best option.
The study confirms the important role that the vascular surgeon has on
the limb-salvage team. We have been developing an approach that is called the
“toe and flow.” This is approach marries a foot surgeon, in terms of
podiatry, with a vascular surgeon. When you put that “toe and flow”
philosophy together, it has an even bigger impact than a clinician working by
his or herself.
This study is also extremely crucial in that it emphasizes the critical
importance of the infrainguinal bypass. This can not be overstated. Many people
have been enamored with endovascular options. But endovascular procedures,
which could improve certain types of stenosis, are in many cases, not enough to
heal high-demand wounds in the extremities.
Therefore, we must marry the endovascular option with an infrainguinal
open bypass option. I think when we do that on the vascular side and combine it
with quality off-loading and surgical and non-surgical treatment on the
podiatry side, good things start to happen.
We are engaged by this data. I think they are important and point a way
to a future where we could keep a few more legs on a few more bodies.
— David G. Armstrong, DPM, MD,
PhD
Professor of surgery and director, Southern Arizona Limb Salvage
Alliance (SALSA), University of Arizona College of Medicine
