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_3757_Библиотеки_им_академика_М_И_Перельмана.pdf
334
S. S. Hans
Proximal Anastomotic Site
See discussion in Chap. 32.
Distal Anastomotic Site
The selected distal target vessel should be free of signicant atherosclerotic disease
from the planned site of anastomosis and distal to that site. However, the presence
or absence of plantar arch should not be a sole consideration for recommendation of
distal arterial bypass graft. In selecting a target artery for patients undergoing distal
bypass with advanced ischemia of the foot (gangrene of the toes), posterior tibial
and anterior tibial artery of suitable diameter and free of signicant disease should
be preferred over the peroneal artery, though later has proven satisfactory target
artery for distal bypass in patients with occlusion of both posterior and anterior
tibial artery. If all the crural arteries are patent (uncommon ndings in patients with
critical limb ischemia), the author’s preference is the posterior tibial artery, then
anterior tibial, followed by peroneal artery.
Conduit Selection
The most satisfactory conduit for infrapopliteal bypass is autologous vein. Options
include ipsilateral and contralateral greater saphenous vein, lesser saphenous vein,
cephalic/basilic vein, and occasionally supercial femoral vein. Because of the better size matching, author prefers in situ conguration to reversed vein as a conduit
for femoral crural and paramalleolar bypasses. Preoperative vein mapping with
duplex imaging should be performed to evaluate the diameter, compressibility, and
wall thickness of the conduit. For optimal patency, the vein diameter should be at
least 3 mm, although satisfactory results have been reported with compressible
veins between 2 and 3 mm used for tibial/peroneal artery bypasses. If adequate
length of greater saphenous vein is not available, a variety or combination of veins
can be used. Upper extremity veins (cephalic or basilic) can provide adequate
length, but due to their thin wall harvesting, the veins can be challenging. Lesser
saphenous vein (patient prone) has also provided suitable conduits for femoral popliteal/infrapopliteal bypasses. Short segments of veins can be connected to one
another with venovenostomies to obtain adequate length. The ends of each vein are
spatulated when performing spliced vein bypasses to aide in creation of wide anastomosis. As a last resort for limb salvage, a prosthetic graft may occasionally be
considered with the use of a distal vein patch or cuff.
33 Femoral-Infrapopliteal (Crural andParamalleolar) Bypass Graft
335
Vessel Control
Small arteries in the calf and distally are controlled with nontraumatic clamps
such as Yasergill (cerebral aneurysm clamp, Aesculap Tuttlingen Germany) or a
micro bulldog clamp. However, clamping a small diameter calcied artery can
result in dissection with resulting occlusion. Tourniquet occlusion in the thigh
prior to the performance of distal anastomosis aids in “bloodless” visualization of
the operative eld with minimal dissection of target vessels in the calf is a signicant advance in performance of small vessel anastomosis for lower extremity arterial reconstruction. Since clamp application to the calcied and friable artery is
avoided, early failure may be improved [2, 3]. Uncommonly in patients with
severe arterial calcication, tourniquet occlusion may not be successful as arteries
may be incompressible.
Special Considerations
Skip incisions in the thigh and calf decrease the incidence of surgical site infection.
Meticulous medial mobilization of the groin lymph nodes and ligation of the lymphatics decrease the incidence of postoperative lymph leak.
In Situ Bypass
1. In some instances, greater saphenous veins may not be able to reach the common
femoral artery for proximal anastomosis. Therefore, common femoral endarterectomy with patch graft is a useful adjunct.
2. Valvulotome– Several commercially available valvulotome LeMaiter, WL Gore,
and leather modication of Mills valvulotome are available, and operator should
be familiar with their use.
3. Arteriovenous stula– Careful ligation of signicant size branches of greater
saphenous vein is necessary to avoid residual arterial venous stula that may
threaten the patency of the graft. Visual inspection of the side branches, Doppler
insolation, and in some instances completion arteriography will aide in the
detection of medium to large size arteriovenous stulas. In general, if the stula’s communication does not outline the deep venous system, it may not require
ligation.
336
Ext. Hall. Long.
Post. Tib. Art.
S. S. Hans
Distal Anastomosis toPosterior Tibial Artery
Exposure ofPosterior Tibial Artery
A proximal one-third of the posterior tibial artery– the proximal segment of posterior tibial artery can be exposed via the popliteal fossa. Tendons of the pes anserinus (sartorius), gracilis, and semitendinosus may need to be divided at their
insertion into the tibia. The medial head of the gastrocnemius is retracted posteriorly, and the soleus muscle is taken down from the soleal line (Figs.33.1, 33.2, and
33.3), taking care to protect the underlying vessels. It is not necessary to divide the
origin of the anterior tibial vein for exposure of the proximal posterior tibial artery.
For exposure of the distal popliteal artery and its bifurcation for femoral popliteal
bypass below the knee the origin of anterior tibial vein as it crosses transversely at
the popliteal artery bifurcation. Distal portion of the tibial-peroneal trunk and its
division into posterior tibial and peroneal artery can be visualized, and anastomosis
carried out with 7-0 CV polypropylene continuous suture usually starting in a parachute manner and then as a continuous suture at the apex of the anastomosis to be
tied on the lateral wall of the arteriotomy in the proximal posterior tibial artery.
This should be carried out as the arteriotomy with Potts scissors is from the 1
o’clock to the 7 o’clock position so that autogenous vein is in satisfactory alignment with the plane of posterior tibial artery thus avoiding any kink at the distal
anastomosis.
Tib. Ant.
Ext. Dig. Long.
Per. Long.
Per. Brev.
Fibula
Soleus
Plantaris
Lat. head.
gastroc
L.S.V.
Fig. 33.1 Transverse section of upper leg 10cm below the knee joint for exposure of proximal
post. Tibial artery
Tibia
Tib. Post
Popliteus
Peron. Art.
G.S.V
Med. head
gastroc
Soleus
head gastroc
soleus fro
33 Femoral-Infrapopliteal (Crural andParamalleolar) Bypass Graft
A
B
C
D
A - Skin incission for prox. P.T. and peroneal art. expo
B - Skin incission for mid. P.T. and peroneal art. expo
C - Skin incission for distal P.T. and peroneal art. expo
D - Skin incission for distal P.T. art expos and planter art.
Fig. 33.2 Skin incision sites for exposure of post. Tibial and peroneal artery
337
Med.
Divided
m
soleal line
Fig. 33.3 Exposure of proximal post. Tibial and peroneal artery with takedown of soleus from the
soleal line
Vein bypass to
prox. P. T. art.
Mid-Segment Posterior Tibial Artery
The exposure of the mid-posterior tibial artery in the mid-calf is obtained by an incision, approximately 8–10cm in length performed 2cm posterior and parallel to the
medial border of the tibia (Fig.33.2). The medial head of gastrocnemius is retracted
338
a
Fig. 33.4 (a, b) Exposure
of mid-post. Tibial artery
S. S. Hans
a
Med. head gastroc.
b
b
P. T. Art.
P. T. nerve
posteriorly along with the soleus. The neurovascular bundle lies in the groove
between the exor digital longus medially and tibialis posterior laterally (Fig.33.4a,
b). Posterior retraction of the soleus and gastrocnemius may result in tear of small
arterial and venous branches. Posterior tibial artery at this site is accompanied by
vena comitans with crossing veins. The crossing veins should be carefully ligated
and divided with 4-0 silk, and 2–3cm length of posterior tibial artery is carefully
exposed.
Distal Posterior Tibial Artery
Posterior tibial artery in the distal one-third of the leg is exposed via longitudinal
incision between the post promedial border of the tibia and tendons achilles
(Fig.33.2). The deep fascia anterior to the tendons achilles is incised, and the neurovascular bundle is exposed between the exor digital longus and exor hallucis
longus. In situ bypass can be easily routed for distal anastomosis at this site.
Reversed vein bypass (prosthetic graft-uncommonly) is tunneled from the groin to
the popliteal fossa deep to the sartorius and then brought down distally in the subcutaneous position. At the ankle, longitudinal incision is made in the middle of the
tip of the medial malleolus and the calcaneus, and the fascial sheath is incised
exposing the posterior tibial artery with accompanying veins (Fig.33.5). Distal
anastomosis should be carried out to one of the plantar arteries if necessary, plantar
arteries exposing the bifurcation of posterior tibial artery toward the heel. Lateral
Flex. dig. long.
33 Femoral-Infrapopliteal (Crural andParamalleolar) Bypass Graft
Fig. 33.5 Exposure of
distal post. Tibial artery
Flex. hall. long.
339
plantar artery is usually larger than the medial plantar artery. Anastomosis to plantar
arteries can be formed in the rst 2cm and may require partial division of the origin
of plantar muscles (Fig.33.6).
Bypass totheAnterior Tibial Artery
Distal anastomosis to the anterior tibial artery in the upper and middle third of the
leg is best accomplished via anterior approach (Fig.33.7). The limb is positioned
with 60°–90° knee exion with a knee “bump” associated with dorsi exion of the
foot, and the operating table slightly tilted to the contralateral side (if right femoral
anterior tibial artery is planned, the right side of the table is tilted upward and the
left side of the table is tilted downward about 15°–20°). A longitudinal incision
about 8–10cm length is made over the patent anterior tibial artery just lateral to the
tibial crest (Fig. 33.8). The fascia is incised longitudinally, and the dissection is
done over the palpable groove between the tibialis anterior and the extensor digitorum longus muscle (Fig. 33.9). The neurovascular bundle is exposed, and the
Weitlaner retractor is applied for exposure. The artery is carefully separated from
the vena comitans, and bridging veins are ligated and divided. Anterior tibial artery
is carefully mobilized with a double-loop silastic loop if tourniquet occlusion technique is not used. An adequate tunnel from the medial aspect of upper calf to the
anterior tibial artery via interosseous membrane is constructed for the passage of
vein graft (Fig.33.10). In patients with tourniquet occlusion, complete mobilization
of the anterior tibial artery is not necessary.
340
long.
Ext. Hall. Long.
Post. Tib. Art.
G.S.V.
Fig. 33.6 Exposure of distal post. Tibial artery and prox. Planter arteries
S. S. Hans
Flex. dig. long.
Post. tib. art.
Nerve
Flex. halluc.
Flex. retinac.
Planter art.
ABD. halluc.
Tib. Ant.
Ext. Dig. Long.
Per. Long.
Per. Brev.
Fibula
Soleus
Plantaris
Lat. head.
gastroc
L.S.V.
Fig. 33.7 Transverse section of upper leg for exposure of proximal ant. Tibial artery
Tibia
Popliteus
Peron. Art.
G.S.V
Med. head
gastroc
Soleus
t.
33 Femoral-Infrapopliteal (Crural andParamalleolar) Bypass Graft
Fig. 33.8 Skin incision for
exposure of prox. Ant.
tibial artery
341
Fig. 33.9 Ant. tibial artery
exposure proximally
between tib. Ant. and ext.
dig. long
Ext. dig.
long.
Nerve
Tib. ant
Ant. A.T. ar
342
Fig. 33.10 Creation of
tunnel from medial upper
calf through interosseous
membrane to prox. Ant.
tibial artery
S. S. Hans
In exposure of the anterior tibial artery in middle third of the leg following a
longitudinal skin incision about 8–10cm long in the anterior compartment about
2cm lateral to the lateral border of tibia, the fascia is incised, and dissection is performed between the deep tibialis anterior muscle, and the extensor hallucis longus
muscle in order to expose the neurovascular bundle, and the vein bypass graft is
tunneled through the interosseous membrane for performance of distal anastomosis
to the anterior tibial artery. Similarly, the dorsalis pedis artery is identied proximally between the tendons of extensor hallucis longus and extensor digitorum longus and more distally between the extensor hallucis brevis and the digitorum longus.
In situ vein bypass can be easily tunneled at this level because of the proximity of
the greater saphenous vein to the dorsalis pedis artery.
The anastomosis to distal anterior tibial and dorsalis pedis artery is performed
following a longitudinal or a slightly curved incision made just above the ankle and
continued in the middle between the medial and lateral malleolus for exposure of
the dorsalis pedis artery (Fig.33.11). Extensor retinaculum is divided, and neurovascular bundle is exposed (Fig.33.12). The subcutaneous plane is suitable for the
tunnel to be used in both in situ and reversed vein bypasses at this level.
.
Ext.
33 Femoral-Infrapopliteal (Crural andParamalleolar) Bypass Graft
Fig. 33.11 Skin incision
for exposure of distal ant.
Tibial artery and dorsalis
pedis artery
343
Fig. 33.12 Exposure of
distal ant. Tibial artery and
dorsalis pedis artery
hall. long.
Ext. dig. long.
Tib. ant.
Nerve
AT. art.
Ext. retinac