SS26. Population-Based Analysis of Inpatient Vascular Procedures: Predicting Future Workload and Implications for Training

Section of Vascular Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter (Impact Factor: 3.02). 01/2012; 55(5):1394-9; discussion 1399-400. DOI: 10.1016/j.jvs.2011.11.061
Source: PubMed
ABSTRACT
The purpose of this study was to analyze the trend in inpatient vascular procedures in the United States over the past decade and predict the future demand for vascular surgeons.
The Healthcare Cost and Utilization Project Nationwide Inpatient Sample was queried to determine the weighted national estimates of inpatient vascular procedures performed on adult patients (age ≥ 18) between 1997 and 2008. Using population estimates from the United States Census Bureau, the per capita rates of inpatient procedures were calculated for age-specific groups (18-64 years, 65-84 years, and ≥ 85 years). The change in per capita rates over the past decade along with population forecasts were used to predict future workload.
There was a net increase of 22% from 971,046 inpatient vascular procedures for all adults in 1997 to 1,188,332 in 2008. During the same time period, the adult population increased by 16% from 198 to 230 million. The age-stratified per capita rates of all vascular procedures were +21% for age 18 to 64; -4% for age 65 to 84; and +18% for age ≥ 85. This resulted in a net increase of 5% (490 to 515 procedures per 100,000 capita) in the per capita rate for all adults. Based on the assumption that trends in age-specific rates remain constant, there is a predicted inpatient workload increase (compared to 2008) of 18% by 2015, 34% by 2020, and 72% by 2030. The vascular workload is predicted to more than double by the year 2040.
Despite a conservative approach of using a population-based analysis of only inpatient procedures, there is a dramatic increase in the predicted vascular workload for the future. The vascular surgery training process will need to adapt to ensure an adequate number of fellowship-trained vascular surgeons is available to provide quality vascular care in the future.

Full-text

Available from: Brian G Rubin, Apr 22, 2016
From the Society for Vascular Surgery
Population-based analysis of inpatient vascular
procedures and predicting future workload and
implications for training
Jeffrey Jim, MD,
a
Pamela L. Owens, PhD,
b
Luis A. Sanchez, MD,
a
and Brian G. Rubin, MD,
a
St. Louis, Mo
Objective: The purpose of this study was to analyze the trend in inpatient vascular procedures in the United States over the
past decade and predict the future demand for vascular surgeons.
Methods: The Healthcare Cost and Utilization Project Nationwide Inpatient Sample was queried to determine the
weighted national estimates of inpatient vascular procedures performed on adult patients (age >18) between 1997 and
2008. Using population estimates from the United States Census Bureau, the per capita rates of inpatient procedures
were calculated for age-specific groups (18-64 years, 65-84 years, and >85 years). The change in per capita rates over the
past decade along with population forecasts were used to predict future workload.
Results: There was a net increase of 22% from 971,046 inpatient vascular procedures for all adults in 1997 to 1,188,332
in 2008. During the same time period, the adult population increased by 16% from 198 to 230 million. The age-stratified
per capita rates of all vascular procedures were 21% for age 18 to 64; 4% for age 65 to 84; and 18% for age >85. This
resulted in a net increase of 5% (490 to 515 procedures per 100,000 capita) in the per capita rate for all adults. Based on
the assumption that trends in age-specific rates remain constant, there is a predicted inpatient workload increase
(compared to 2008) of 18% by 2015, 34% by 2020, and 72% by 2030. The vascular workload is predicted to more than
double by the year 2040.
Conclusions: Despite a conservative approach of using a population-based analysis of only inpatient procedures, there is a
dramatic increase in the predicted vascular workload for the future. The vascular surgery training process will need to
adapt to ensure an adequate number of fellowship-trained vascular surgeons is available to provide quality vascular care
in the future. (J Vasc Surg 2012;55:1394-1400.)
Data from the United States Census Bureau shows that
the population is increasing and aging.
1,2
This growth is
expected to continue for the next few decades.
3
The most
dramatic growth is in the elderly population 65 years of
age and in those 85 and older. There are two main factors
that may account for this. First, a large wave of population
density (the so-called “baby boomer” generation) hit re-
tirement age in 2011. Furthermore, people simply live
longer than they had in the past. The life expectancy at birth
had increased to a record high of 78.2 years in 2009.
4
In
addition, the death rates for 10 of the 15 leading causes of
death decreased significantly from 2008 and 2009.
Cardiovascular disease remains the leading cause of
death and morbidity for the elderly. The prevalence of this
disease process has steadily increased at a rate of 1% to 2%
annually.
5
As age is a significant risk factor for cardiovascu-
lar disease, this growth is expected to continue for the next
few decades. The American Heart Association projects an
additional 27 million people with hypertension, 8 million
with coronary artery disease, 4 million with stroke, and 3
million with heart failure in 2030 relative to 2010.
6
With
the increase in prevalence of cardiovascular diseases and the
aging population, the economic burden and the use of
healthcare resources will continue to increase in the future.
Over the past several years, numerous studies have
reported current or future shortage of the physician work-
force.
7
As vascular surgery continues to be the speciality
with the lowest number of active physicians, the increase in
the future vascular workload may potentially have a devas-
tating effect on the delivery of quality vascular surgical
care.
8
The purpose of this study is twofold. With the
changing population dynamic and increasing prevalence of
cardiovascular disease, the first objective is to evaluate the
trend in inpatient vascular procedure volume in the United
States over the past decade. Second, we will use population
estimates from the United States Census Bureau and prior
trends in inpatient care to predict the future caseload and
resultant demand for vascular surgeons.
METHODS
Data source. Population estimates were obtained
from the United States Census Bureau.
1-3
Inpatient proce-
dural data was collected from the Nationwide Inpatient
Sample database, which was created as part of the Health-
care Cost and Utilization Project by the Agency for Health-
care Research and Quality. The Nationwide Inpatient Sam-
ple is the largest all-payer inpatient care database in the
From the Section of Vascular Surgery,
a
and the Department of Internal
Medicine,
b
Washington University School of Medicine.
Author conflict of interest: none.
Presented at the Society for Vascular Surgery Vascular Annual Meeting,
Chicago, Ill, June 17, 2011.
Additional material for this article may be found online at www.jvascsurg.org.
Reprint requests: Jeffrey Jim, MD, Washington University School of Med-
icine, 660 S. Euclid Avenue, Campus Box 8109, St. Louis, MO 63110
(e-mail: jimj@wudosis.wustl.edu).
The editors and reviewers of this article have no relevant financial relationships
to disclose per the JVS policy that requires reviewers to decline review of any
manuscript for which they may have a competition of interest.
0741-5214/$36.00
Copyright © 2012 by the Society for Vascular Surgery.
doi:10.1016/j.jvs.2011.11.061
1394
Page 1
United States and contains data from approximately 8
million hospital stays each year. The data available approx-
imates a 20% stratified sample of all hospital discharges.
Total procedural numbers were calculated using sampling
strata and weights as determined by Healthcare Cost and
Utilization Project.
Patient selection. The study period ranged from
1997 to 2008 and was limited only to patients 18 years
old. Utilizing International Classification and Diagnosis,
Ninth Revision procedure codes, we identified patients
who underwent vascular procedures. We subdivided proce-
dure codes into categories as noted in the Appendix (online
only). The following were further categorized as “major”
vascular procedures: open carotid, open abdominal aortic,
thoracic-subclavian, endovascular thoracic/abdominal aor-
tic, and peripheral procedures. There were no exclusion
criteria.
Data collection and analyses. The weighted national
estimates for inpatient vascular procedures were tabulated
for each calendar year and also for three age subgroups: 18
to 64 years; 65 to 84 years, and 85 years. The per capita
rates were derived by using the number of procedures and
census estimates. For future projections, an assumption is
made that the trends during the past decade will persist at
the same rate into the future. The changes in per capita
rates over the study period were then combined with pop-
ulation forecasts to predict future workload.
RESULTS
Trends in inpatient vascular procedure volume.
The population estimates during the study period can be
found in Fig 1. The adult (18 years) population grew
from 198 million (1997) to 229 million (2008), a total
increase of 16.0%. There was a differential rate of increase
between the age subgroups: 16.6% (164.0 to 191.1 mil-
lion) for age 18 to 64; 10.2% (30.3 to 33.4 million) for age
65 to 84; and 39.3% (3.9 to 5.5 million) for age 85.
The number of inpatient vascular procedures per-
formed during 1997 (beginning of study period) and 2008
(end) can be found in Table I. There was a trend in decrease
in the total number of open vascular surgical procedures:
open carotid (26.5%), open aortic (49.1%), periph-
eral (24.5%), dialysis access (30.1%), and amputation
(4.6%). There was a concomitant increase in less invasive
treatment modalities. Percutaneous interventions had an
overall increase of 296.8% (103,754 to 411,672 proce-
dures). The International Classification and Diagnosis,
Ninth Revision procedure code for endovascular abdomi-
nal aortic aneurysm repair was introduced in 2000 and for
thoracic endovascular aortic repair in 2005. As such, the
change in volume for endovascular aortic procedures was
calculated from the year 2001 to 2008. During the 8-year
period, the total volume increased by 191.4% (14,261 to
41,553). Over the entire study period from 1997 to 2008,
“major” vascular procedures decreased by 21.3% (478,430
to 381,138) and the total number of inpatient vascular
procedures increased by 21.9% (971,076 to 1,183,322).
Using the available population estimates, the inpatient
vascular procedure per capita rates were calculated and can
be seen in Fig 2. The rate of percutaneous interventions
increased for all adult patients (from 52 to 129/100,000
capita) with the largest percentage increase (449%, from
104 to 568) in patients age 85 and older. Compared to
baseline levels in 2001, there was an increase of 169% (7 to 18)
in endovascular aortic procedures by 2008. With the increase
in percutaneous and endovascular procedures, there was a
decrease in “major” vascular procedures across all age groups.
Overall, in terms of all vascular procedures, there was an
increase in patients aged 18 to 64 (21%) and 85 (18%) and
a decrease in those aged 65 to 84 (4%). For the entire adult
population, there was an increase of 5% (490 to 515 proce-
dures/100,000 capita) from 1997 to 2008.
Predicting the future vascular caseload. The pre-
dicted future population estimates can be found in Fig 3.
There will be a significant amount of growth in the coming
decades, with the largest increase in patients over the age of
65 (Table II). Overall, the adult population will increase by
35.6% to over 311 million people by the year 2040. With
the assumption that the per capita increase in inpatient
procedures over the study period will persist into the future,
the predicted future workload is shown in Fig 4. Using the
0
50000000
10000000
15000000
20000000
25000000
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Population All 18+
Population Age 18-64
Population Age 65-84
Population Age 85+
Age Group 1997 2008 Change
All 18+ 198.1M 229.9M 16.0%
Age 18-64 164.0M 191.1M 16.6%
Age 65-84 30.3M 33.4M 10.2%
Age 85+ 3.9M 5.5M 39.3%
Fig 1. United States population estimates during study period.
Table I. Volume of inpatient procedures in the United
States from 1997 to 2008
Inpatient procedures 1997 2008 Change
Open carotid 170,941 125,573 26.5%
Open aortic 104,868 53,405 49.1%
Thoracic-subclavian 15,916 19,633 23.4%
Endovascular aortic 14,261
a
41,553 191.4%
Peripheral 186,705 140,974 24.5%
Percutaneous 103,754 411,672 296.8%
Dialysis 89,441 54,488 30.1%
Amputation 149,559 142,735 4.6%
“Other” procedures 149,892 193,289 29.0%
“All” vascular 971,076 1,183,322 21.9%
“Major” vascular 478,430 381,138 21.3%
a
Procedure number in the year 2001, the first full year the procedure code
was available.
JOURNAL OF VASCULAR SURGERY
Volume 55, Number 5
Jim et al 1395
Page 2
year 2008 as reference, the future volume is as follows: 18%
increase to 1,394,000 procedures by 2015; 34% increase to
1,590,000 procedures by 2020; 72% increase to 2,031,000
procedures by 2030; and more than double (106% in-
crease) with 2,440,000 procedures by the year 2040.
DISCUSSION
In this study, we used data obtained from a large
population-based database to determine the trends in the
AC
BD
0.00
100.00
200.00
300.00
400.00
500.00
600.00
700.00
800.00
Percutaneous All 18+
(Per capita) Age 18-64
(Per capita) Age 65-84
(Per capita) Age 85+
Age Group Change
All 18+ 241%
Age 18-64 263%
Age 65-84 206%
Age 85+ 522%
0.00
200.00
400.00
600.00
800.00
1000.00
1200.00
"Major" All 18+
(Per capita) Age 18-64
(Per capita) Age 65-84
(Per capita) Age 85+
Age Group Change
All 18+ (31.3%)
Age 18-64 (22.3%)
Age 65-84 (32.5%)
Age 85+ (21.7%)
0
10
20
30
40
50
60
70
80
90
100
Endo aortic All 18+
(Per capita) Age 18-64
(Per capita) Age 65-84
(Per capita) Age 85+
Age Group Change
All 18+ 147%
Age 18-64 194%
Age 65-84 135%
Age 85+ 172%
0.00
500.00
1000.00
1500.00
2000.00
2500.00
All vascular All 18+
(Per capita) Age 18-64
(Per capita) Age 65-84
(Per capita) Age 85+
Age Group Change
All 18+ 4.0%
Age 18-64 16.8%
Age 65-84 (2.8%)
Age 85+ 17.4%
Fig 2. Per capita (per 100,000 capita) rates of (A) percutaneous, (B) endovascular aortic, (C) “major,” and (D) all
inpatient vascular procedures in the United States during the study period.
0
50000000
100000000
150000000
200000000
250000000
300000000
350000000
1997 2008 2010 2015 2020 2030 2040
Population All 18+
Population Age 18-64
Population Age 65-84
Population Age 85+
Age Group 2015 2020 2030 2040
All 18+ 7.6% 12.9% 24.2% 35.6%
Age 18-64 4.9% 7.2% 11.8% 20.6%
Age 65-84 21.6% 44.6% 90.0% 101.0%
Age 85+ 15.5% 21.1% 60.5% 160.6%
Volum e
4.0%
16.8%
(2.8%)
17.4%
Fig 3. United States future population predictions.
Table II. Predicted increase in the United States adult
population (compared to baseline values from 2008)
Age group 2015 2020 2030 2040
All 18 7.6% 12.9% 24.2% 35.6%
Age 18-64 4.9% 7.2% 11.8% 20.6%
Age 65-84 21.6% 44.6% 90.0% 101.0%
Age 85 15.5% 21.1% 60.5% 160.6%
JOURNAL OF VASCULAR SURGERY
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1396 Jim et al
Page 3
weighted national estimates of inpatient vascular proce-
dures and to predict the increase in future demand. Over
the study period from 1997 to 2008, we found a trend away
from what had traditionally been considered as “major”
vascular procedures (such as open aneurysm repair, open
carotid procedures, and peripheral bypasses) with replace-
ment by endovascular and percutaneous-based interven-
tions. Overall, we found an increase of 5% in the per capita
rates of total procedures for the entire adult population.
The driving force behind this increase remains uncertain.
With the rise in cardiovascular disease burden in our pop-
ulation, the increasing need for vascular procedures can
result if patients are “sicker” and thus additional interven-
tions are needed. However, the minimally invasive nature
and safety profile of percutaneous-based endovascular in-
terventions likely remains an important factor.
9
Prior studies have attempted to predict the future vas-
cular workload with the use of census projections and
pre-existing treatment trends.
10-12
In 1996, the Commit-
tee on Workforce Issues of the Society for Vascular Surgery
and the North American Chapter International Society
for Cardiovascular Surgery predicted that the total num-
ber of vascular operations for the year 2020 would be
1,020,067.
10
A more recent study from 2004 predicted
that the caseload in 2030 will range from a minimum of
1.33 million to a maximum of 2.17 million.
12
The projec-
tions from this study mirrored these prior reports. We
project close to 1.6 million procedures in the adult popu-
lation by 2020 and just over 2 million by the year 2030. By
2040, the total number of procedures will more than
double from the documented rates in 2008 to well over 2.4
million. While we used an expected increase of 5% in the per
capita rates of vascular procedures, the driving force in this
increase is the several fold higher predicted growth in the
population.
With this increase in the vascular workload, the physi-
cian workforce will need to expand accordingly to ensure
continued access to quality health care. This problem is not
limited to vascular surgery alone and, over the past several
years, numerous studies have concluded that the US phy-
sician workforce is facing current or future shortage on
multiple levels. This has been demonstrated in reports
showing shortages at the state and national levels as well as
in specialty-specific studies.
7
This wide encompassing phe-
nomenon likely demonstrates the overwhelming effect of
the expanding population as the dominant factor as op-
posed to any change in treatment paradigm that may be
seen in any particular specialty (such as growth of endovas-
cular procedures in vascular surgery).
In 2006, the Association of American Medical Colleges
(AAMC) released a position statement on the issue of
physician shortage and made recommendations for an in-
crease of medical school enrollment over the next decade
by 30% from the 2002 level.
13
Furthermore, the AAMC
recommended expansion of graduate medical education
positions to accommodate the increase in medical school
graduates. However, the Balanced Budget Act of 1997
currently places a cap and limits the number of postgradu-
ate training positions. The Resident Physician Shortage
Reduction Act of 2009 calls for an increase of 15% in the
number of residents in approved training programs. How-
ever, the proposal has remained under consideration by the
Senate Finance Committee since its introduction on May 5,
2009. Furthermore, the Patient Protection and Affordable
Care Act, a product of the health care reform agenda of the
current administration, includes no provisions to increase
the number of physicians. As such, it remains “incumbent
on surgical leadership to adapt the existing resources to the
realities of our current system.”
14
The problem of future workforce shortage is particu-
larly vexing for vascular surgery. At the current time, vas-
cular surgery already is one of the smallest specialities in the
nation. In an AAMC report using data from 2007, there
were 2610 active vascular surgeons with only 2392 that
participated in patient care (others had major activities
designated as teaching, research, or administration).
8
Over
one-third (37.2%; 971 of 2610) of active vascular surgeons
are aged 55 or older. Population data estimates that there
are 115,564 people per active vascular surgeon, by far the
largest number of all the specialities. To contrast, there
were 14,022 people per physician for the 21,511 cardiovas-
cular disease specialists and 11,268 people for each of the
26,279 active general surgeons. As it stands now, vascular
surgeons only perform a fraction of the vascular procedures
in this country. Medicare and state database information
shows that vascular surgeons perform approximately 70% of
all endovascular aneurysm repairs and 30% of peripheral
stents and carotid stents.
15,16
To address the workforce
shortage, a potential solution is to increase the number of
fellowship-trained vascular surgeons. There has been a sig-
nificant growth in the number of training positions (from
56 in 1989 to 120 in 2009) over the past 2 decades. Despite
this, there is still a failure to meet the estimated minimum of
160 vascular graduates needed each year for the expected
demand in 2030.
17
There remain major barriers to continuing the increase
in the number of training positions. First and foremost is
the cost associated with training additional surgeons. It has
1997 2008
Volume (1 0
3
) 971 1183
Change **
2015
1394
17%
2020
1590
34%
2030
2031
72%
2040
2440
106%
Fig 4. Predicted future workload for all inpatient vascular proce-
dures in the United States.
JOURNAL OF VASCULAR SURGERY
Volume 55, Number 5
Jim et al 1397
Page 4
been estimated that it will cost over $1 billion to train
enough vascular surgeons by 2030.
18
Even if the financial
restraints are eliminated, there remains a limitation in the
number of candidates that apply to vascular surgery. In 8 of
the past 10 years, there were fewer applicants than available
training positions.
19
Furthermore, the number of female
and minority trainees in vascular surgery remains among
the lowest of all the specialities.
8
In 2006, the 5-year integrated program was approved
for vascular surgery training. Since its approval, there has
been an incredible growth in the number of programs
across the country. In the 2010 match, there were 20
programs offering 22 positions. It remains to be seen if
these new integrated positions will supplement, rather than
replace, traditional training positions. However, the push
for these programs has undeniably led to increasing medical
student interest in vascular surgery. There has been a more
concerted effort at the institutional and national level in
outreach to medical students. As a result, the quality of top
vascular surgery applicants is comparable to top general
surgery residency applicants, yet the vascular applicant had
a higher percentage with advanced degrees, more publica-
tions, and more involvement in cardiovascular research.
20
There must remain a conscious effort to expose medical
students to vascular surgery.
21
If we are able to pique
interest in more students, in particular women and minority
candidates, then there will certainly be a demand for addi-
tional training positions.
Predicting the future certainly is difficult and not an
exact science. To perform our calculations, we had to make
the assumption that trends from the past can be extrapo-
lated into the future. This assumption is an important
limitation and certainly does not account for potential
changes in health care delivery in the face of increasing
prevalence of vascular disease and associated risk factors.
We have already seen the dramatic impact of a new thera-
peutic modality (endovascular and percutaneous-based in-
tervention) on the way patients are cared for. There may be
additional technologic advances that eliminate the need for
reintervention or improvements in medical therapies that
reduces the effects of atherosclerosis. Furthermore, utiliza-
tion may differ in the future with changes from healthcare
reform if certain procedures are found to provide only
marginal benefits at significant costs. However, we can only
use the past decade of experience as the basis for modeling
the influence of these potential changes.
With the above limitation in mind, we therefore pur-
posely used a conservative approach to calculate the future
workload. We used only an inpatient database and did not
account for the high number of vascular procedures per-
formed in the outpatient setting. Over the past decade,
there has been a decrease in the ratio of inpatient vs
outpatient interventions. This has been clearly demon-
strated in patients with critical limb ischemia, claudication,
and other vascular diagnoses.
22
During the study period,
the 30% decline in inpatient dialysis procedures, despite an
increase of over 66% in the prevalence of patients with
endstage renal disease, also points to a shift to the ambula-
tory surgery setting.
23
As such, it is important to keep in
mind that the observed trends and the calculated projec-
tions likely provide a significant underestimation of the
overall future volume. Even with the intended underesti-
mation, we still predict a significant future increase in
vascular workload.
The role of other physician specialities in the future
delivery of vascular care also remains unclear. In addition to
vascular surgeons, many other specialties (including cardio-
vascular disease specialists, general surgeons, interventional
radiologists, and others) also perform vascular procedures
in this country. However, the future physician shortage is
not unique to vascular surgery and can be seen in these
other specialties as well.
7
Furthermore, the role of the
general surgeon in future vascular care merits additional
discussion. While the number of vascular procedures per-
formed by nonfellowship-trained general surgeons has
steadily declined over the past 2 decades, there remain
some general surgeons that perform vascular operations in
relatively large numbers.
24
However, this will likely change
in the future with the increasing recognition of vascular
surgery as a distinct specialty. The Surgical Council on
Resident Education has developed a general surgery resi-
dency curriculum outline that does not expect the general
surgeon to be able to provide comprehensive management
of most vascular problems.
25
As such, it is unlikely that
newly trained and future general surgeons can continue to
provide quality vascular surgical care.
Therefore, to increase the number of accredited fellow-
ship-trained positions must remain a priority among the
leaders in vascular surgery. If there is a failure to do so,
other specialists will no doubt relish the opportunity to fill
the void left by the missing vascular surgeon. The qualifi-
cations and speciality of physicians who perform vascular
procedures had been, and will likely remain, a hotly debated
and controversial topic. Regardless, the delivery of high
quality care should remain the ultimate goal in the future.
The only way that vascular surgeons can ensure that we
reach this goal is to provide a sufficient amount of well-
trained vascular surgeons in the future.
CONCLUSIONS
Over the past decade, the types of inpatient vascular
procedures being performed changed dramatically, with a
shift from major open operations to endovascular and
percutaneous-based interventions. Overall, there has been
an increase driven by an increase in per capita rates and
more significantly by population growth. Despite using a
conservative approach of using a population-based analysis
of only inpatient procedure volume, there will be a dramatic
increase in the number of future vascular surgical proce-
dures. This increasing vascular workload will need to be
carefully evaluated, and training of additional physicians
implemented, to assure that quality vascular care can be
provided in the future.
JOURNAL OF VASCULAR SURGERY
May 2012
1398 Jim et al
Page 5
AUTHOR CONTRIBUTIONS
Conception and design: JJ
Analysis and interpretation: JJ, PO, BR, LS
Data collection: JJ, PO
Writing the article: JJ
Critical revision of the article: JJ, PO, BR, LS
Final approval of the article: JJ, PO, BR, LS
Statistical analysis: JJ, PO
Obtained funding: Not applicable
Overall responsibility: JJ
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Additional material for this article may be found online
at www.jvascsurg.org.
DISCUSSION
Dr Julie Ann Freischlag (Baltimore, Md). I had a question
about risk factor modification and prevalence of disease, such as we
think there is going to be more diabetes and more obesity but the
impact of less smoking and perhaps better control of lipids. How
do you even try to attempt that in your analysis? Is there a way we
can look at that?
Dr Jeffrey Jim. I think it is probably impossible to account for
something like that. We started by looking at trends and changes,
such as improvement in medical therapy over the past decade,
which were accounted for in the calculations. However, there is a
lot that we cannot predict about the future. Certainly, these
include new techniques or even new medical therapy that may
completely eliminate atherosclerosis if we get lucky.
Dr Matthew Mell (Stanford, Calif). It seems from your data
that major open vascular procedures decreased over time, yet
percutaneous procedural volumes increased. Did you consider the
impact of other specialties’ offering percutaneous treatment and
the proportion of patients cared for by vascular surgeons on future
predictions?
Dr Jim. I will start off by saying that shortage of providers is
not something that will be unique to vascular surgery. The Amer-
ican College of Cardiology has also noted this and published a
report recommending an increase in training positions. There are
many published studies showing vascular surgeons perhaps are
already performing less than half of the peripheral interventions. If
we do not increase the total workforce, the market share of the
vascular surgeons will only continue to decrease.
Dr Jonathan Beard (Sheffield, United Kingdom). The Na-
tional Vascular Registry in the United Kingdom has shown exactly
what you have shown, a fall in major open vascular procedures and
JOURNAL OF VASCULAR SURGERY
Volume 55, Number 5
Jim et al 1399
Page 6
a dramatic increase in endovascular surgeons. My question is, do
you think if this trend continues we are going to move toward an
office-based specialty where, because of volume outcome relation-
ships, only a few vascular surgeons will actually need to be trained
to perform major open vascular surgery?
Dr Jim. I think ultimately the need for major open vascular
procedures will not disappear in the future. There will continue to
be other specialists that can perform percutaneous interventions.
However, if there remain a limited number of surgeons, then they
will still have to perform these open procedures because they are
the only ones that are adequately trained and qualified to perform
them.
Dr Samuel Ahn (Los Angeles, Calif). About 10 years ago, I
published a very similar article and made a very similar presentation
as you did. I made a bunch of predictions and came to the same
conclusion: increased clinical need, not enough doctors, and so on.
I was wondering if you had a chance to go back and look at that
study, as well as other studies that followed (for example, Dr Craig
Kent behind me here also published several papers trying to predict
our future.) Have you gone back and looked at which of those
papers were accurate and how accurate they were in predicting the
future? Also, various authors used different methods and databases
to make their prediction; were you able to make any prediction as
to which of those methods and databases are the most predictable?
Dr Jim. I think certainly trying to turn prediction into a
science is not going to be possible. Each of the studies you
mentioned, as well as others in the literature, all has their own
merits and limitations. Similarly, there is no single database or
prediction model that is perfect. I think there is a need to try to be
comprehensive and this includes looking at ambulatory care cen-
ters. However, it is difficult to look at all 50 states and picking one
single state and then extrapolating may not be the best technique
either.
Dr John Ricotta (Washington, DC). I want to just have you
address the workforce issue. Our initial hopes with the 0-5 pro-
gram was that we were going to increase the total number of
trainees. It is not clear to me that that is going to be the case, or at
least not in the way that we want to. It seems to me that a
significant number of programs are simply going to go from one
paradigm to the other and leave us with a relatively modest increase
in the total number of trainees. So I would like your thoughts
about what some of the roadblocks are to increasing total vascular
graduates and maybe what the Society might be able to do to
facilitate that?
Dr Jim. I think you are correct in saying that most of the 0
5 positions are really replacing traditional 5 2 and not creating
additional spots. However, with the push for these programs is a
side effect of a significant increase in interest in our field by medical
students. With the 0 5, there has been a concerted effort in
outreach. If we are able to pique interest in women, minority
groups, and other medical students, then ultimately you are going
to have the demand for additional training spots. Even if we have
more positions right now and you do not have enough people
interested, that is not going to work either.
Dr K. Craig Kent (Madison, Wisc). I have a concern about
your methodology and then a comment. You alluded to this issue
in your presentation, but, at this point in time, the majority of
vascular interventions in this country are percutaneous and if you
look at the coding, over half of these procedures are coded as
outpatient procedures. So using the National Inpatient Sample,
you have grossly underestimated the number of percutaneous
procedures that are being performed and likewise the potential
growth rate of vascular interventions. The comment is somewhat
similar to John Ricotta’s. There are going to be many more
vascular interventions performed over the next 10 to 20 years, and
the question is, who is going to perform those interventions? If
vascular surgeons do not perform these procedures, I assure you
that there are other interventionalists that will rise to the occasion
and take on this work. So the solution for us is to train more
vascular surgeons. But we seem to have hit a plateau. We just do
not seem to be able to increase the number of fellowship training
programs. I would challenge everyone in the audience that if we are
going to solve this problem, the solution is looking into each of our
individual practices to see if there is the potential to develop a
training program. We need to produce more vascular surgeons.
Dr Jim. I definitely agree with your comment and it was our
intent to stimulate discussion in the future of our field. To address
your first question, when we chose to focus only on an inpatient
database, we knew we were going to grossly underestimate. De-
spite the underestimation, there was still a very dramatic increase in
what we found for the future. We admit that it would certainly be
more comprehensive to include the ambulatory care setting. How-
ever, we shied away from using only a limited number of represen-
tative states and then try to extrapolate, because certainly practice
patterns in terms of ambulatory treatment is very different between
states. We therefore chose to be conservative and still show a
dramatic result.
JOURNAL OF VASCULAR SURGERY
May 2012
1400 Jim et al
Page 7
Appendix, online only. Inpatient vascular procedures
categories by International Classification and Diagnosis,
9th Revision, procedure codes
“Major” procedures: include open carotid surgeries,
open abdominal aortic, thoracic-subclavian, endovascular
thoracic/abdominal aortic, and peripheral
Open carotid
3812 Endarterectomy, other vessels of head and neck
3802 Incision of vessels, other vessels of head and neck
3832 Resection of vessel with anastomosis, other vessels of head
and neck
3842 Resection of vessel with replacement, other vessels of head
and neck
3862 Other excision of vessels, other vessels of head and neck
3882 Other surgical occlusion of vessels, other vessels of head
and neck
398 Operations on carotid body, carotid sinus and other
vascular bodies
Open abdominal aortic
3804 Incision of vessel, aorta
3806 Incision of vessels, abdominal arteries
3814 Endarterectomy, aorta
3816 Endarterectomy, abdominal arteries
3834 Resection of vessel with anastomosis, aorta
3836 Resection of vessel with anastomosis, abdominal arteries
3844 Resection of vessel with replacement, aorta
3846 Resection of vessel with replacement, abdominal arteries
3864 Other excision of vessels, aorta
3866 Other excision of vessels, abdominal arteries
3884 Other surgical occlusion of vessels, aorta, abdominal
3886 Other surgical occlusion of vessels, abdominal arteries
3924 Aorta-renal bypass
3925 Aorta-iliac-femoral bypass
3926 Other intra-abdominal vascular shunt or bypass
3954 Re-entry operation (aorta)
3955 Reimplantation of aberrant renal vessel
Thoracic-subclavian
3805 Incision of vessels, other thoracic vessels
3815 Endarterectomy, other thoracic vessels
3835 Resection of vessel with anastomosis, other thoracic vessels
3845 Resection of vessel with replacement, other thoracic vessels
3865 Other excision of vessels, thoracic vessel
3885 Other surgical occlusion of vessels, aorta, thoracic vessel
3922 Aorta-subclavian-carotid bypass
3923 Other intrathoracic vascular shunt or bypass
Endovascular thoracic/abdominal aortic
3971 Endovascular implantation of graft in abdominal aorta
3973 Endovascular implantation of graft in thoracic aorta
Peripheral
3929 Other (peripheral) vascular shunt or bypass
Appendix, online only. Continued
(Lower extremity vascular procedure)
3808 Incision of vessels, lower limb arteries
3818 Endarterectomy, lower limb arteries
3838 Resection of vessel with anastomosis, lower limb arteries
3839 Resection of vessel with anastomosis, lower limb veins
3848 Resection of vessel with replacement, lower limb arteries
3849 Resection of vessel with replacement, lower limb veins
3868 Other excision of vessels, lower limb arteries
3869 Other excision of vessels, lower limb veins
3888 Other surgical occlusion of vessels, lower limb arteries
3889 Other surgical occlusion of vessels, lower limb veins
(Upper extremity vascular procedure)
3803 Incision of vessels, upper limb vessels
3813 Endarterectomy, upper limb vessels
3833 Resection of vessel with anastomosis, upper limb vessels
3843 Resection of vessel with replacement, upper limb vessels
3863 Other excision of vessels, upper limb vessels
3883 Other surgical occlusion of vessels, upper limb vessels
Percutaneous
0063 Percutaneous insertion of carotid artery stent(s)
3950 Angioplasty or atherectomy of noncoronary vessel
3972 Endovascular repair or occlusion of head and neck vessel
3979 Other endovascular repair (of aneurysm) of other vessels
3990 Insertion of nondrug-eluting, noncoronary artery stent(s)
9910 Injection or infusion of thrombolytic agent
Dialysis access
3927 Arteriovenostomy for renal dialysis
3942 Revision of arteriovenous shunt for renal dialysis
3943 Removal of arteriovenous shunt for renal dialysis
3953 Repair of arteriovenous fistula
Lower extremity amputations
8410 Lower limb amputation, not otherwise specified
8411 Amputation of toe
8412 Amputation of through foot
8413 Disarticulation of ankle
8414 Amputation of ankle through malleoli of tibia and fibula
8415 Other amputation below knee
8416 Disarticulation of knee
8417 Amputation above knee
843 Revision of amputation stump
Other procedures
387 Interruption of vena cava
3949 Other revision of vascular procedure
3952 Other repair of aneurysm
3956 Repair of blood vessel with tissue patch graft
3957 Repair of blood vessel with synthetic patch graft
3958 Repair of blood vessel with unspecified type of patch graft
3991 Freeing of vessel
3999 Other operations on vessels
-
JOURNAL OF VASCULAR SURGERY
Volume 55, Number 5
Jim et al 1400.e1
Page 8
  • Source
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