Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_905_Библиотеки_им_академика_М_И_Перельмана.pdf
260
a
b
I. A. Laskowski et al.
received U.S. Food and Drug Administration
(FDA) approval in 2016. This system consists of
an IVL generator, a connector cable, and a catheter (Fig.21.15a). The IVL catheter comprises an
array of integrated lithotripsy emitters for the
localized delivery of pulsatile mechanical energy
and an integrated balloon (Fig.21.15b). The IVL
catheter is available in multiple sizes ranging
from 2.5mm to 12mm and compatible with a 5
French to 8 French sheath and has working
lengths of 110cm and 135 cm to treat aorta to
tibial and peroneal vessels (Fig.21.16).
The IVL catheter contains an ination lumen,
a guidewire lumen, and the lithotripsy emitters
(Fig.21.16). The ination lumen is used for ination and deation of the balloon with a 50:50
saline: contrast medium mixture. The guidewire
lumen enables the use of a 0.014-inch guidewire
to facilitate the advancement of the catheter to
and through the target stenosis. The system is
designed as “over-the-wire” (OTW) with a
110 cm or 135 cm shaft working length, and a
minimum of a 5 French sheath is required at the
access site. The balloon is located near the distal
tip of the catheter. Two radiopaque marker bands
within the balloon denote the length of the balloon to aid in the positioning of the balloon during treatment. The balloon is designed to provide
an expandable segment of a known length and
diameter at a specic pressure. The proximal hub
has three ports: one for ination/deation of the
balloon, one for the guidewire lumen, and one for
connection to the IVL connector cable. The IVL
catheter will deliver a maximum of 300 pulses or
10cycles of 30 pulses per cycle for L6 and M5+
catheters and 160 pulses or 8cycles of 20 pulses
per cycle for S4. It is recommended not to exceed
180 pulses in the same treatment segment.
Procedural Steps
The insertion site is accessed in a standard fashion using a micro-puncture system under ultra-
Fig. 21.15 Shockwave medical peripheral IVL system (a) with IVL catheter (b). (Reproduced with permission from
Shockwave Medical)
21 Surgical Decision-Making in Vascular Surgery: Practical Approaches to New Innovative Techniques…
261
Fig. 21.16 Shockwave peripheral IVL catheter balloons. (Reproduced with permission from Shockwave Medical)
sound guidance, followed by upsizing to an
appropriately sized sheath. Angiography is performed to localize and delineate the arterial
lesion (Figs. 21.17a and 21.18a). Appropriate
anticoagulation is initiated. A balloon catheter
size is then selected in a 1:1 ratio with the reference vessel diameter. The IVL catheter is prepared by lling a 20 mL syringe with 5 mL of
half-strength contrast medium and attaching the
syringe to the ination port on the catheter hub.
The syringe is pulled back at least 3 times to
release vacuum and allow the uid to replace the
air in the catheter. The guidewire port of the IVL
catheter is then ushed with saline, and the
protective sheath from the catheter is removed,
and the IVL connector cable is inserted into a
sterile sleeve and attached to the IVL generator.
The 0.014-inch guidewire is used to traverse the
treatment site under uoroscopic guidance. The
IVL catheter is then loaded over the guidewire
and advanced through the sheath to the treatment
site using the marker bands to aid in positioning.
Once the IVL catheter is positioned and conrmed with uoroscopy, the IVL balloon is
inated up to 4atm, and IVL is activated for up to
20 pulses for S4 and 30 pulses for M5+ and L4 by
pressing the activation button (Figs.21.17b-c and
21.18b). The balloon is then inated up to 6atm
under uoroscopy. Then, the balloon is deated,
and additional treatments can be performed as
needed by repositioning the IVL and repeating
the sequence as necessary. If multiple inations
are required due to a lesion length greater than
the IVL balloon length, the recommended balloon overlap is at least 1 cm. After treatment,
completion angiography is performed to assess
post-intervention results (Figs. 21.17d and
21.18c).
262
cd
bc
ab
I. A. Laskowski et al.
Fig. 21.17 Right lower extremity angiography demonstrating severe long segment calcied stenoses of the
anterior tibial artery and tibioperoneal trunk (a) treated
with 4 mm × 60 mm IVL catheter with a total of 300
a
pulses (b-c). Completion angiography illustrating signicant luminal expansion of the treated vessels with no
residual stenoses (d)
Fig. 21.18 Angiography illustrating severely calcied left iliac arterial system (a) treated with the IVL (b) alone.
Completion angiography demonstrates signicantly improved ow to the left iliac arterial system (c)
21 Surgical Decision-Making in Vascular Surgery: Practical Approaches to New Innovative Techniques…
263
Clinical Evidence ofIntravascular
Lithotripsy inPeripheral Artery
Disease
The DISRUPT PAD I and II were multi-center
retrospective studies of prospectively collected
data to investigate the short-term safety and efcacy of the IVL for treating calcied, occlusive
femoropopliteal lesions [51, 52]. The results
showed 100% procedural success with a dramatic reduction in stenosis severity, high acute
gain, and minimal vessel injury. There were no
major adverse events or revascularizations after
the index procedure, and vessel patency was
durable out to 6months, with primary patency
rates of 82.1%. The DISRUPT PAD III RCT
trial was the rst randomized controlled study
comparing the outcomes of IVL and percutaneous transluminal angioplasty (PTA) to prepare
the lesions before drug-coated balloon (DCB) or
stenting for occlusive femoropopliteal lesions
[53]. Compared to the PTA group, the IVL
group had higher procedural success and balloon/stent expansion with signicantly lower
residual stenosis and ow- limiting dissection
rates (Table21.1 and Fig.21.19). Two-year follow-up results revealed signicantly higher primary patency in the IVL group versus PTA
group (70.3% vs. 51.3%; P = 0.003) [54].
DISRUPT PAD III observational study (OS)
was a prospective, non-randomized, multi-center, single-arm study conducted to assess the
real-world acute performance of IVL in the
treatment of calcied, stenotic peripheral arteries that may not qualify for inclusion in the RCT
[55]. Of the 1531 lesions treated in the iliac,
common femoral, supercial femoral, popliteal,
and infrapopliteal arteries, 90% presented with
moderate or severe calcication, with an average calcied length of 115mm. The use of IVL
resulted in a nal residual diameter stenosis of
24% with only 0.7% and 0.2% experiencing
nal dissections (Type D–F) and perforations,
respectively (Table 21.1 and Fig. 21.19).
Notably, there were no instances of embolization, thrombus formation, no-reow or abrupt
closure.
Table 21.1 Summary of DISRUPT PAD III RCT and
OS trials
DISRUPT
PAD III RCT
No. 306 (153 IVL) 1367
Vessel SFA/popliteal Iliac, CFA, SFA/
Dissection
(type D-F)
Perforation 0% 0.2%
Embolization 0% 0%
Slow ow/
no-reow
Abrupt closure 0% 0%
Thrombus 0% 0%
Fig. 21.19 Efcacy of IVL in reducing the residual
diameter stenosis in Disrupt PAD III RCT and OS
studies
0% 0.7%
0% 0%
DISRUPT PAD III
OS
popliteal,
Infrapopliteal
The sub-analysis of the DISRUPT PAD III OS
study showed promising results in the use of IVL
in calcic infrapopliteal lesions, with 100% successful IVL catheter delivery and no ow- limiting
dissection, perforation, distal embolization, slow
ow, no-reow, or abrupt closure [56]. The
Disrupt BTK study was a prospective, nonrandomized, multi-center feasibility, and safety
trial composed of 20 patients (mean age
79.0±9.6years; 14 men) with Rutherford category 1 to 5 ischemia with moderate to severe calcied infrapopliteal stenosis treated with IVL
and followed for 30 days [57]. IVL catheter
delivery was successful in 95%, with a 46.5%
acute reduction in percent diameter stenosis of
264
target lesions, one dissection, and 2 stents placed.
None of the subjects experienced thrombus formation, abrupt closure, distal embolization, or
perforation, with no composite of major adverse
events at 30days. There were no device-related
complications. The results of this pilot study
demonstrated that calcied, stenotic infrapopliteal arteries can be safely and successfully treated
with intravascular lithotripsy. The effect of IVL
on calcic plaque under the stent strut has also
been reported in the carotid, mesenteric, and
lower extremity arterial systems. While IVL can
modify the calcic plaque under a peripheral
stent, improving stent expansion, the long-term
impact of this approach will need to be examined
in larger clinical studies.
Conclusion
IVL represents a promising endovascular technique for limb salvage and improved outcomes in
patients with calcied PAD. Clinical evidence
underscores its safety and effectiveness in achieving luminal gain and enhancing vessel patency
with minimal risk of complications. However,
further research is warranted to elucidate its longterm benets and applicability in specic patient
populations.
The May–Thurner Syndrome
The May–Thurner Syndrome (MTS) is compression of the left common iliac vein from the right
iliac artery and vertebral body. This condition
was rst described by an autopsy study performed by May and Thurner in 1957 [58]. The
clinical condition of left iliac vein stenosis was
described by Cockett [59].
Anatomy
The left iliac vein is present between the body of
the lumber vertebra and the right iliac artery
(Fig.21.20). This causes a physiologic stenosis
I. A. Laskowski et al.
Fig. 21.20 Left common iliac vein compression by right
common iliac artery
which is very common. A CT scan study shows
that 25% of asymptomatic patients have 50% stenosis and two-thirds of asymptomatic patients
have 25% stenosis [60]. When this stenosis
becomes exaggerated and causes clinical symptoms, it is diagnosed as MTS.
Clinical Presentation
MTS is present two times more commonly in
women as compared to men. MTS has two distinct clinical presentations which include thrombotic vs non-thrombotic.
Patients with non-thrombotic MTS have
chronic left lower extremity symptoms of venous
insufciency. Nonspecic symptoms of chronic
venous disease include heaviness, achiness,
swelling, throbbing, and itching (HASTI
Symptoms). A signicant number of patients
have venous claudication which is dened as
pain and stiffness of the leg with exercise and
improvement with rest and elevation.
Swelling of the lower extremity is a common
condition with differential diagnosis of venous
insufciency, deep venous thrombosis, lymphedema, heart failure, medications, leg injury,
morbid obesity, and prolonged inactivity in a sitting position.
Chronic venous disease is a common disorder
that has manifestations ranging from varicose
veins to venous ulcerations. Chronic venous disease is best classied by CEAP classication
21 Surgical Decision-Making in Vascular Surgery: Practical Approaches to New Innovative Techniques…
265
which includes clinical, etiological, anatomic,
and pathophysiological categories. Nonthrombotic MTS patients can have concomitant
lower extremity varicose veins due to primary
supercial venous reux along with left iliac vein
obstruction.
Thrombotic MTS occurs due to deep venous
obstruction of the left iliac vein from left iliac
vein stenosis. Deep venous thrombosis can occur
due to a history of thrombophilia or transient risk
factors such as pregnancy, surgery, prolonged
immobilization, or oral contraceptive pills.
Thrombotic MTS is often diagnosed with acute
ileo-femoral DVT. These patients present with
acute pain and swelling of the left lower extremity. In more severe cases, patients can present
with phlegmasia cerulea dolens. Some patients
with thrombotic MTS present with chronic left
ileo-femoral DVT.These patients have a history
of DVT which was treated with anticoagulation
in the past and have chronic post-phlebitic syndrome. These patients have venous claudication
with severe venous stasis changes in the left leg.
Multiple other conditions cause iliac vein and
IVC stenosis and thrombosis. These conditions
include iliac vein and IVC thrombosis due to
thrombophilia; iliac vein and IVC stenosis due to
congenital webs and atresia; external compression due to malignancy; a catheter or IVC lterassociated stenosis and thrombosis. These
conditions necessitate the same diagnostic studies and often similar treatment approaches as
MTS.
Imaging Studies
1. Duplex scan is the most important initial diag-
nostic study. Duplex scan for suspected
patients in the vascular lab involves lower
extremity duplex and iliac vein and inferior
vena cava scan. A lower extremity duplex
scan is useful for the diagnosis of deep venous
thrombosis and deep and supercial venous
reux. An inferior vena cava and iliac vein
study is useful to determine any deep venous
thrombosis in this segment. The extent of left
iliac vein stenosis is harder to determine by
duplex scan.
2. Contrast CT scan with venography has higher
sensitivity and specicity to detect left iliac
vein stenosis and deep venous thrombosis. CT
scan is also useful to determine external
causes of compression of the iliac vein by
malignancy, uterine broid, lymphadenopathy, or hematoma.
3. Magnetic resonance venography is an alternative to CT venography. This study is rarely
used due to the length of time it takes to do the
test as compared to a contrast CT scan.
4. Venography: Venogram of iliac veins and
inferior vena cava can be done by femoral
vein, popliteal vein, and jugular vein based on
the treatment plan. A venogram will show
severe iliac vein stenosis and occlusion; however, it will miss moderate iliac vein stenosis
even in multiple projections.
5. Intravascular Ultrasound (IVUS): IVUS is the
gold standard for diagnosis of MTS. IVUS
provides information regarding the degree
and length of stenosis. This information is
useful for accurate deployment of stents. It
should be noted that physiologic stenosis of
50% is present in many asymptomatic
patients. Treatment with iliac vein stents
should be done in patients with severe symptoms that interfere with the patient’s
activities.
Treatment ofMTS
Non-thrombotic MTS often presents with lower
extremity chronic venous disease. These patients
are initially treated with compression stockings,
leg elevation, exercise involving ambulation, and
weight loss if needed. Patients are evaluated with
a lower extremity venous duplex scan. Patients
who have signicant saphenous venous reux
and fail conservative treatment are rst treated
with radiofrequency ablation of the saphenous
vein. Patients who continue to have swelling of
the left lower extremity undergo a duplex scan of
iliac veins and IVC. These patients who have
severe symptoms undergo venogram and IVUS
procedures. We do a venogram for nonthrombotic patients by accessing the common
femoral vein by ultrasound guidance. A 6 Fr
266
ab
I. A. Laskowski et al.
Fig. 21.21 (a) Venogram showing severe common iliac vein stenosis (black arrow), White arrows showing lling of
collateral veins. (b) Venogram after left common iliac vein stent placement
sheath is placed in the femoral vein, and venogram is performed in AP and oblique projections.
Venogram generally shows patent left iliac vein
and IVC with no signicant stenosis. Stenosis on
venogram is only seen if it is severe (Fig.21.21a).
Next 6 Fr sheath is exchanged over wire for 9 Fr
sheath. IVUS is performed over 0.035 guide wire
(Fig.21.22a). In patients with severe symptoms
and with the presence of over 50% stenosis on
IVUS, a left common iliac vein stent is placed.
IVUS is useful to determine the extent of the iliac
vein stent. Generally, Wallstent, Zilver Vena, or
Abre stent are deployed. The diameter of the
stents is 14–16 mm, and the length of stents
ranges from 60 to 100mm. Extending the stent
beyond the stenosis into IVC is desirable
(Fig. 21.21b). Angioplasty of the iliac vein is
done using a 14 to 16-mm balloon. A completion
IVUS is done (Fig.21.22b). Patients are on bed
rest for 2hours and then discharged home. Postprocedure patients are placed on anticoagulation
for 4weeks. They are then placed on antiplatelet
for 6months. Patients undergo duplex scans at 1
month and 6months to conrm the patency of the
stent. This procedure has been shown to improve
patient symptoms with a 4-year patency of 93%
[61].
Thrombotic MTS presents with either acute
ileo-femoral vein DVT or chronic ileo-femoral
vein DVT.Clinical presentation and management
of these two conditions differ.
Patients with acute thrombotic MTS present
with severe acute pain and swelling of the left
lower extremity. These patients are often unable
to ambulate due to the extent of pain. Duplex
scan is done which will conrm ileo-femoral vein
acute DVT.The initial treatment of acute thrombotic MTS is leg elevation in the Trendelenburg
position and high-dose intravenous heparin protocol if the patient has no contraindication for
anticoagulation. For patients who have respiratory distress or hypoxia, a contrast CT scan of the
chest is done to check for pulmonary embolism.
Some patients also undergo CT venography to
determine the extent of thrombosis. The patient is
then booked in the angio-suite for mechanical
21 Surgical Decision-Making in Vascular Surgery: Practical Approaches to New Innovative Techniques…
267
ba
Fig. 21.22 (a) IVUS shows the left common iliac vein (curved arrow) and right common iliac artery (top arrow). (b)
IVUS of left common iliac vein after stent
thrombectomy, thrombolysis, angioplasty, and
stenting. Placement of temporary or removable
IVC lters is considered in patients who have
limited lung reserve due to pulmonary embolism
or free-oating thrombus. Most patients do not
require IVC lter placement.
In the angio-suite, patients are placed in the
supine position and a duplex scan is done for
patency of femoral and popliteal veins. The procedure is most commonly performed under conscious sedation; however, some patients require
monitored anesthesia care or general anesthesia.
We can access the left popliteal vein percutaneously with ultrasound guidance with the patient
in a supine position with the leg bent. Initially, a
6 Fr sheath is placed, and a venogram is done to
a patent segment of the femoral vein. A glide
wire along with a glide catheter is used to go
through the thrombosed femoral and iliac vein up
to IVC. Next 6 Fr sheath is exchanged over a wire
for a 9 Fr sheath. We use 8 Fr Angiojet-Zelante
catheters for thrombolysis and mechanical
thrombectomy of femoral and iliac vein thrombosis. Initially, a power pulse is used for thrombolysis with up to 10mg of tissue plasminogen
activator (TPA). TPA is allowed to dwell in the
thrombus for 20 minutes. Next mechanical
thrombectomy is done with multiple passes
through the thrombus. A repeat venogram is done
to assess the extent of clearance. In some cases,
clot maceration is done with repeat mechanical
thrombectomy. IVUS is done to access the extent
of left iliac vein stenosis, and stenting of the iliac
vein is done from IVC to the distal extent of stenosis [64, 65].
After the procedure anticoagulation with heparin is continued. This is later switched to
Lovenox, DOAC, or Coumadin for 6 months.
The patient is also evaluated for thrombophilia
and if present will need lifelong anticoagulation.
This procedure has replaced catheter-directed
thrombolysis in our institution which takes 1 to
2days of treatment in the intensive care and multiple visits to the angio-suite.
Patients with acute thrombotic MTS can also
be treated with an indigo penumbra 8 Fr suction
device and an Inari 13-F ClotTriever device.
ClotTriever device has the advantage that it can
be used for chronic thrombotic MTS.
Chronic thrombotic MTS presents with postphlebitic syndrome with leg pain, swelling,
advanced chronic venous stasis, and venous claudication. These patients undergo diagnostic studies including venous duplex and CT venography.
Patients are initially seen in an outpatient setting
and are brought to the angio-suite electively.
268
I. A. Laskowski et al.
ClotTriever procedure involves percutaneous
access of the patent distal femoral or popliteal
vein under ultrasound guidance. Initially, a 6 Fr
sheath is placed and a venogram is done to access
the thrombosed segment. Using a glide wire and
catheter thrombosed segment of the femoral and
iliac vein is crossed up to IVC. Next 13 Fr
ClotTriever sheath is placed, and the funnel is
deployed. Next ClotTriever catheter is placed
into IVC over the guide wire proximal to the
thrombus. The coring element and collection bag
are opened, and the coring element is pulled back
to remove the clot from the vessel wall. If resistance is met during thrombectomy, coring element is disengaged and re-engaged beyond the
stenosis. The area of iliac vein stenosis is treated
with angioplasty. After the thrombectomy, iliac
stenosis is stented. The main advantage of this
system is that it can treat both acute and chronic
deep venous thrombosis. This system also does
not require thrombolytic treatment. The results of
the ClotTriever device have been outlined in the
Cloud Registry which shows 91% of patients
have near complete thrombectomy (determined
by Marder score) with an adverse event rate of
0.2%. Patients had immediate improvement of
symptoms as shown by the Villalta scale before
and after the procedure [62, 63].
Patients with thrombotic MTS who are treated
with iliac stents have 2-year primary assisted and
secondary patency of 88 and 96% [66].
Conservative Treatment
Many patients with isolated left leg swelling and
non-thrombotic MTS elect not to have interventional treatment. These patients are treated with
compression stockings, leg elevation, and exercise as tolerated. Some of these patients with
chronic swelling have components of lymphedema, and they can be managed by manual lymphatic drainage and/or venous and lymphatic
pumps.
In our clinical practice, we have also treated
patients with acute thrombotic MTS with longterm anticoagulation and conservative treatment.
We have seen some of these patients recover with
minimal sequelae. CAVENT trial [67] showed a
lower incidence of postphlebitic syndrome in
patients with ileo-femoral DVT treated with
catheter- directed thrombolysis (CDT) as compared to anticoagulation alone. ATTRACT [68]
trial showed no improvement with CDT as compared to anticoagulation. Both of these trials
were not specic for MTS and did not employ
newer technology.
Patients with chronic thrombotic MTS can
also be treated conservatively. These patients
require anticoagulation if they have thrombophilia or recurrent DVTs. Some patients without
thrombophilia can be treated with a 6-month
course of anticoagulation and then it can be
stopped.
Conclusions
MTS presents with left lower extremity swelling
with venous claudication symptoms. Imaging
studies including venous duplex, venogram, and
IVUS are useful for the diagnosis of
MTS.Physiologic stenosis of the left iliac vein is
common and therefore accurate diagnosis
requires a combination of clinical criteria and
imaging study. Patients with non-thrombotic
MTS are treated with left common iliac vein
angioplasty and stent placement. Patients with
acute and chronic thrombotic MTS are treated
with thrombectomy of the ileo-femoral segment
along with iliac vein angioplasty and stent. These
patients require long-term anticoagulation. Some
patients with less severe symptoms can be treated
conservatively.
Evaluation ofaPatient
forHemodialysis Access
Hemodialysis is the most prevalent form of renal
replacement therapy (RRT), with the others being
peritoneal dialysis and kidney transplant. For
patients receiving hemodialysis, their longevity
is proportional to the quality of their dialysis,
which in turn is proportional to the quality of
access to their vasculature. It is important that the
vascular access for hemodialysis be reliable, adequate to deliver prescribed dialysis, suitable to
patient’s given needs, and with low complication
rates. The options for vascular access include:
21 Surgical Decision-Making in Vascular Surgery: Practical Approaches to New Innovative Techniques…
269
1. Arteriovenous stula: a surgical connection
between an artery and a vein. This is usually
in the upper extremity, but can be performed
in the lower extremity.
2. Arteriovenous graft: a conduit is connected
between an artery and a vein. The conduit is
directly accessed for dialysis.
3. Central venous catheter: a exible, double
lumen tube inserted into a large, central vein.
The National Kidney Foundation’s Kidney
Disease Outcomes Quality Initiative (KDOQI)
has provided evidence-based guidelines for
hemodialysis vascular access since 1996, with
the most recent update being in 2019 [69].
These are commonly referred to as the
“KDOQI guidelines” and form the basis for
much of the decision-making regarding the care
of chronic kidney disease (CKD) patients and
their vascular access. The Work Group which
wrote the guidelines was multidisciplinary and
included nephrologists, radiologists, vascular
surgeons, and vascular access nurses. While the
emphasis of the previous guidelines published in
2006 was “stula rst,” an important new concept introduced in the most recent update is that
of the End-Stage Kidney Disease (ESKD)
Life-Plan.
The ESKD Life-Plan is an individualized
roadmap of the patient’s vascular access needs
over their lifetime. It helps prepare for, create,
and preserve access for dialysis, as well as for the
next vascular access before the current one fails.
This considers the patient’s current and anticipated medical, functional, and psychosocial status to determine the optimal dialysis modalities
and access options. Important factors to assess
include:
1. Patient goals, preferences, and life
expectancy.
2. Comorbidities and functional status.
3. Vascular anatomy and suitability for different
access types.
4. Prior access history and complications.
5. Social support and logistics.
Keeping this ESKD Life-Plan in mind, the
access surgeon’s goal should be to provide the
right access, in the right patient, at the right time,
for the right reasons. This involves a collaborative process between the patient, their care partners, and the multidisciplinary care team. This
shared decision-making approach ensures the
Life-Plan aligns with the patient’s goals, preferences, and values. The Life-Plan requires regular
review and updates as the patient’s condition,
needs, and desires can change over time.
Pre-Access Evaluation by theSurgeon
Initial evaluation of a patient for new hemodialysis access emphasizes physical exam.
1. Arterial.
(a) Character of peripheral pulses, including
brachial, radial, and ulnar arteries.
(b) Allen test, assess adequacy of palmar
arch collateralization.
2. Venous.
(a) Assess for edema, arm size, and collateral
veins which could indicate central venous
obstruction.
(b) Visible, palpable veins such as cephalic
and basilic veins.
(c) Look for older, failed, previous stulas or
grafts.
3. Pump.
(a) Assess for signs of heart failure.
Vein mapping should routinely be obtained.
This could be performed in the ofce by the surgeon or can be done in a peripheral vascular lab.
Mapping includes vessel diameter, depths, and
quality. While there is not a strict minimum vein
or artery diameter on vessel mapping, arteries
and veins <2 mm in diameter should undergo
careful evaluation for quality and feasibility to
create a functioning access. There are emerging
studies that can be done to be more inclusive for
traditionally excluded vessels.
KDOQI Guidelines for Access Selection