(cid:142)(cid:3) Having completed the anastomoses release the clamps ensure haemo- stasis a nd close the wounds in layers with a subcuticular suture or staples to the skin. Femorofemoral graft (5 year patency 60 \200\22380%) Indications (cid:142)(cid:3) Unilateral iliac occlusive disease not amenable to stenting. (cid:142)(cid:3) Patients with adequate circulation in one leg with patent iliofemoral vessels on the donor limb. The operation can be done under local anesthesia in unfit patients. It may be used as a lim b salvage procedure in patients with a patent profunda femoris artery on the symptomatic si de with rest pain but in the absence of gangrene. Exposure Expose the groin vessels bilaterally through vertical incisions. Procedure (see Fig. 12.16) (cid:142)(cid:3) Using finger dissection or a tunneling instrume nt fashion a subcutane- ous tunnel suprapubically between the two groin incisions and pass an 8mm Dacron graft through the tunnel from one side to the other (Fig. 12.16A). Alternativ ely, the graft can be taken from the common iliac to femoral artery (Fig 12.16B). (cid:142)(cid:3) Give the patient 5000IU heparin and apply vascular clamps to the common femoral artery and its branches on the donor side. (cid:142)(cid:3) Make a longitudinal incision in the common femoral artery and carry out an end-to-side anastomosis with a continuous 5/0 Prolene suture (Fig. 12.16C and D). (cid:142)(cid:3) Apply a vascular clamp to the graft adjacent to the completed anasto- mosi s and release the femoral clamps to restore circulation to the donor limb. (cid:142)(cid:3) On the ischaemic side make a longitudinal incision in the common femoral artery extending into the origin and first part of the profunda femoris. (cid:142)(cid:3) Tailor the graft obliquely applying gentle traction to reduce the crimp- i ng and fashion an end-to-side anastomosis with continuous 5/0 or 6/0 Prolene (Fig. 12.16E). (cid:142)(cid:3) Release the clamps and ensure haemostasis before closing the wounds in layers. EXTRA-ANATOMIC BYPASS1 435 (A) (B) Dacron graft tunneled via Cave of Retzius Iliofemoral graft (D) (C) (E) CFA CFA PFA PFA SFA SFA Fig. 12.16 Iliofemoral and femorofemoral graft CHAPTER 12 Peripheral vascular surgery 436 Iliofemoral/unilateral aortofemoral/iliopopliteal Indications Unilateral iliac occlusive di sease, not suitable for angioplasty or stent Incision In flank gently curved incision from costal margin to lateral edge of rectus sheat h and 2 \200\2233cm above the inguinal ligament. Distally vertical incision in the groin or lower thigh. Procedure (cid:142)(cid:3) Divide the external oblique in the line of its fibers, cut the i nternal oblique and transversalis in the line of the incision and using finger dissection o pen up the retroperitoneal space, displacing the peritoneum medially. (cid:142)(cid:3) Identify the aortic bifurcation, common and external iliac vessels and control them with slings. Insert a self retaining retractor. (cid:142)(cid:3) Select an appropriate graft (8mm Dacron/PTFE). Give the patient 5000IU heparin, clamp the appropriate vessels proximally and distally and make a longitudin al arteriotomy (aorta/iliac). (cid:142)(cid:3) Trim the graft obliquely and fashion an end-to-side anastomosis with continuous 4/0 or 5/0 Prolene. Clamp the graft just distal to the suture line and release t he vessel clamps. (cid:142)(cid:3) Tunnel the graft to the groin or popliteal incision, clamp the vessels pro ximally and distally and fashion an end-to-side anastomosis to the arteriotomy with continu ous Prolene. Close the wounds in layers. Carotid to subclavian bypass Indications (cid:142)(cid:3) Subclavian steal syndrome (cid:14 2)(cid:3) Occlusive disease of the proximal subclavian (cid:142)(cid:3) It may be a preoper ative requirement in endovascular stenting of thoracic aortic dissection or thoracic aortic aneurysm if stent placement is required to cover the orifice of the subclavian. Position Supine with the head turned to the opposite side and a pad under the shoulders. Incision 6 \200\2238 cm incision parallel to and 1 \200\2232cm above the medial third of th e clavicle. Procedure (see Fig. 12.17) (cid:142)(cid:3) Make a supraclavicular incision 2cm above the m edial end of the clavi- cle extending from the clavicular head of the sternomastoid. Divide the platysma and clavic ular head of the sternomastoid and dissect through the fascia and the scalene fat pad (take care to avoid the thoracic duct on the left). (cid:142)(cid:3) Identify the phrenic nerve on the scalenus anterior and preserve it. Divid e the scalenus anterior and locate the subclavian with the thyrocervical trunk and free it. The brachial plexus lies laterally in the wound. EXTRA-ANATOMIC BYPASS1 437 (A) Subclavian art. CCA (B) CCA Subclavian art. Fig. 12.17 Carotid-subclavian bypass CHAPTER 12 Peripheral vascular surgery 438 (cid:142)(cid:3) Expose the carotid artery in the medial aspect of the incision by retrac- tion of the sternal head of sternomastoid. Dissect anterior to the internal jugular vein, o pen the carotid sheath and mobilize the common carotid artery passing slings to control the vessel. (cid:142)(cid:3) Heparinise the patient with 5000IU heparin and apply clamps to the subclavian and then the carotid. (cid:142)(cid:3) Select a suitable Dacron graft and fashion the carotid anastomosis end-to- side first at right angles to the carotid. The graft is brought either anterior or posterio r to the jugular vein and clamped adjacent to the anastomosis the carotid clamps being remo ved to restore cerebral circulation. (cid:142)(cid:3) Now tailor the graft to length and cut it obliquely to match the arteri- o tomy in the subclavian artery and fashion an end-to-side anastomosis to the artery. (cid:142)(cid:3) Secure haemostasis and close the wound in layers. Obturator bypass Indications (cid:142)(cid:3) Graft sepsis localized to the groin (cid:142) (cid:3) Crush injury to the groin (cid:142)(cid:3) Infected femoral aneurysms in IV drug ab user. Position Supine with the entire leg prepared to allow abduction/lateral rotation. The groin wound is covered with an adhesive drape and the skin of the thigh is prepared. Procedure (cid:142)(cid:3) Expose the iliac vessels by a retroperitoneal approach. If there is no infection in the patent graft it may be used as the donor site (unlikely), otherwise use th e common iliac or aorta as a donor site. (cid:142)(cid:3) Locate the obturator foramen just posterior to the superior pubic ramus by following the obturator nerve along the pelvic brim. (cid:142)(cid:3) Reflect the peritone um from the external iliac towards the pubic ramus. Incise the obturator membrane anteriorally and medially to avoid the nerve and vesse ls. (cid:142)(cid:3) Expose the above knee popliteal artery via a vertical skin incision dis- p lace the sartorius posteriorly and mobilize the artery with slings. (cid:142)(cid:3) Tunnel a suitable graft to the supragenicular incision via the obturator foramen. Give the patien t 5000IU heparin and clamp the iliac vessel. (cid:142)(cid:3) Make a longitudinal arterioto my, cut the graft obliquely and fashion an end to side anastomosis with continuous 5/0 Prolene. When the anastomosis is complete clamp the graft adjacent to the suture line and release the iliac or aortic clamps ensuring the join is watertight. Fashion a similar anastomosis to the popliteal artery above the knee. (cid:142)(cid:3) Close the wounds in layers. This page intentionally left blank CHAPTER 12 Peripheral vascular surgery 440 Infrainguinal bypass Aims To restore the circulation to the lower limb affected by occlusiv e vascu- lar disease. Indications (cid:142)(cid:3) Crippling intermittent claudication \200\224the majority of cl audicants are managed by interventional radiological procedures or conservatively (cid:142)(cid:3) Critical ischaemia (cid:142)(cid:3) Limb salvage. These bypass procedures make use of the native long saphenous vein (reversed vein graft/in situ vein graft) or a pr osthetic graft of either Dacron or PTFE or a prosthetic graft with a distal vein cuff/patch . The graft is attached proximally to the common femoral artery and distally to the above k nee/below knee popliteal artery (femoropopliteal bypass) or to the infracrural vessels in t he case of femorodistal bypass for limb salvage. Preoperative preparations Good quality arteriography to define the extent of the disease an d to assess the distal run-off. Position Supine with the knee flexed to 45(cid:13), the hip flexed and externally rotated. Prepare the lower abdomen, groin and entire leg, placing the foot in a sterile, transparent bag. If a prosthetic graft is to be used administer a broad spectrum antibiotic at inducti on of anesthetic. Incisions See access to major blood vessels (p392) for exposure of the groin and popliteal vessels. Femoropopliteal bypass grafting Procedure (cid:142)(cid:3) Make the initial incision vertic ally in the groin across the inguinal crease following the line of the long saphenous vein. (cid:142)(cid:3) Expose the femoral vessels in the groin and either the above knee or below knee popliteal artery. (cid:142)(cid:3) Mobilize the common femoral, SFA and profunda arteries as normal (ligate o verlying lymphatics to avoid lymphocele). If a reversed vein graft/in situ vein graft is co ntemplated preoperative vein mapping is helpful. (cid:142)(cid:3) Using finger dissection expose the entire length of the necessary long sap henous vein, ligating the venous tributaries with silk or an absorb- able tie (4/0) or liga clips ensuring you do not compromise the vein by ligating too close to the main trunk. INFRAINGUINAL BYPASS1 441 (cid:142)(cid:3) Leave the vein in situ until the moment of harvest. When both the donor an d recipient site vessels have been exposed, mobilized, and slung with tapes, remove the vei n and attach a bulldog clamp to the upper end of the reversed vein. Using a Tibbs cannula o f appropriate size flush the reversed vein with heparinised saline and check for leaks befo re marking the vein with an ink line along its length to help avoid twisting during its pas sage along the subsartorial tunnel. (cid:142)(cid:3) Pass a tunneling instrument subsartorially between the donor and recipient incision sites (an additional small above knee incision as for exposure of the ab ove knee popliteal artery may help in tunneling to a below knee site). In the case of a syn thetic graft (usually 6/8mm Dacron/PTFE) pass the graft as above through the tunnel ensurin g no kinks and straighten the leg to ensure there is a sufficient length of graft or vein t o reach the target vessels without tension or excess. (cid:142)(cid:3) Give the patient 5000IU heparin intravenously and apply arterial clamps and fashion an arteriotomy with a 15 blade knife extending it with Potts scissors to an appropriate length. (cid:142)(cid:3) Spatulate the end of the vein or synthetic graft and anastomose to the dis tal vessel with a continuous 5/0 or 6/0 Prolene. A similar anastomo- sis is fashioned end-t o-side to the common femoral artery using a 5/0 Prolene suture. Release the clamps and ensu re good flow in the graft. (cid:142)(cid:3) Having ensured haemostasis, close the wounds in layers. In situ vein graft May be used in femoropopliteal reconstruction as above or in femorodis- tal grafting for limb salvage where the distal anastomosis is fashioned to the anterior tib ial, posterior tibial or peroneal arteries (for exposure of these vessels see p392 \200\223 5). The minimum diameter of vein acceptable as a conduit is 3mm. Procedure (see Fig. 12.18) (cid:142)(cid:3) Expose the femoral vessels as above and the rec ipient vessels likewise. Expose the long saphenous vein throughout its length taking care n ot to undermine the skin flaps. Ligate the side branches and the sapheno- femoral junction exposed, its branches being divided and ligated. (cid:142)(cid:3) Apply a pediatric Cooley clamp to the common femoral vein and the saphenof emoral junction disconnected leaving a cuff of common femo- ral vein exposed so that it can be oversewn with a continuous 5/0 or 6/0 Prolene suture and the Cooley clamp removed. The first valves in the long saphenous vein are divided under direct vision and clamps ap- plie d to the femoral vessels. (cid:142)(cid:3) Fashion a vertical arteriotomy in the common femoral artery (the site is d etermined by the position of the saphenofemoral junction relative to the bifurcation of the common femoral artery) and carry out an end-to-side arteriovenous anastomosis carried out with continuous 5/0 or 6/0 Prolene. After completion release the occluding clamps and blood flow is established in the vein to the next competent valve. CHAPTER 12 Peripheral vascular surgery 442 (cid:142)(cid:3) Pass a Halls/LeMaitre vein valve cutter retrogradely from below through the anastomosis and withdrawn it to achieve valvulotomy evidenced by pulsatile bloo d flow throughout the graft (several passes rotating the cutters may be necessary). Achieve appropriate control of the distal vessels; trim the graft to length and spatulate the end. Anastomose the graft to a suitable site on the popliteal artery or one of its three branch es below the knee. (cid:142)(cid:3) Check that the foot is perfused and for pulses either by palpation or using Doppler. Close the wounds in layers. Adjuvant techniques in infragenicular prosthetic grafts The patency of below knee prostheti c grafts may be improved by the use of interposition vein cuffs or patches The Miller cuff (see Fig. 12.19) (cid:142)(cid:3) Harvest a segment of vein 3 \200\2234mm d iameter from a suitable site (lateral tributary of long saphenous vein or short saphenous vein). (cid:142)(cid:3) Open the vein longitudinally along its length and place a double ended sut ure (5/0 or 6/0 Prolene) in the middle of the posterior wall of the arteriotomy and the mid dle of the vein sheet with the intimal surface innermost. (cid:142)(cid:3) Suture around the apex and heel of the arteriotomy until the two ends meet in the middle of the anterior wall of the arteriotomy. Trim the excess vein and sutured to gether the vein cuff ends. Now cut the distal end of the PTFE graft obliquely to match the length of the cuff and sutured to it with continuous 5/0 or 6/0 Prolene. The Taylor patch (see Fig. 12.19) (cid:142)(cid:3) Harvest a segment of vein and open it as described above. (cid:142)(cid:3) Cut the PTFE graft obliquely and the heel is sutured to the proximal apex of the arteriotomy. (cid:142)(cid:3) Make a 2cm longitudinal incision in the toe of the graft. Trim the corners of the vein patch and suture it to the apex of the arteriotomy taking care to avoid any narrowing and continue the suturing proxi- mally along the arteriotomy and PTFE incisi on. INFRAINGUINAL BYPASS1 443 (A) CFA CFV Halls vein valve cutter LSV CFA CFV (B) CFA (C) LSV LSV SFA (D) Fig. 12.18 In situ vein graft CHAPTER 12 Peripheral vascular surgery 444 Miller cuff Taylor patch Fig. 12.19 The Miller cuff and Taylor patch This page intentionally left blank CHAPTER 12 Peripheral vascular surgery 446 Popliteal artery entrapment syndrome This occurs as a developmental defect, the popliteal a rtery passing medial to and beneath the medial head of gastrocnemius or a slip thereof lead - ing to compression of the artery. Five anatomical variants are recognized and lead to int ermittent claudication symptoms in young people. The pedal pulse classically vanishes on ac tive plantar flexion of the foot against resistance or on passive dorsiflexion. Preoperative findings Angiography (cid:142)(cid:3) Medial deviation proximal popliteal arte ry (cid:142)(cid:3) Segmental occlusion mid popliteal artery (cid:142)(cid:3) Post stenotic dilatation Any two or more of these are diagnostic of the condition. CT or MRI scan will d efine the anatomy precisely. The posterior approach is better for all anatomical variants a nd allows easy repair of the artery if necessary. Position Prone on the table under general or epidural anesthesia with the leg slightly flex ed. Incision Lazy S incision with the horizontal portion in the popliteal crease. Procedure (cid:142)(cid:3) Deepen the incision and divide the deep fascia longitudinally ta king care to avoid damage to the sural nerve. (cid:142)(cid:3) Identify and protect the tibial nerve passing a sling around it to allow g entle traction. Identify the popliteal vein, the artery is not in its usual position and is best identified high in the popliteal fossa as it exits from the adductor canal. (cid:142)(cid:3) Trace the artery inferiorly and divide the compressing band of muscle/ fas cia, mobilizing the entire length of the artery. Fix the transacted head of gastrocnemius t o the femur with an absorbable suture. (cid:142)(cid:3) If the artery is occluded or its wall thickened or fibrotic, apply bulldog clamps proximally and distally and resect the damaged segment after administration of 5000 IU heparin. (cid:142)(cid:3) Harvest a suitable length of long saphenous vein and replace the dam- aged segment of artery with a reversed vein graft sutured end-to-end to the divided artery ends with continuous 5/0 Prolene. (cid:142)(cid:3) Ensure haemostasis and close the wound in layers without drainage. This page intentionally left blank CHAPTER 12 Peripheral vascular surgery 448 Peripheral aneurysms The majority affect the femoral or popliteal artery and are often asso ci- ated with aortic aneurysmal disease. Carotid aneurysm These are rare and are either true aneurysms or post traumatic, the bifurc ation being the commonest site of true aneurysm disease. The choice of treatment is depende nt on the size and location, resection and reconstruction with an autogenous conduit being the preferred method, particularly if infection is suspected. Procedure See pp386 \200\2237, 406 \200\2237 Femoral artery aneurysm Two principal types: (cid:142)(cid:3) Confined to the common femora l (cid:142)(cid:3) Involves origin of profunda. Indications Surgery is usually carried out if size greater than 2.5cm diameter or for complications (embolisation/thrombosis/rupture) or symptoms (pain/ venous or neural compression). Position Supine with lower abdomen and entire leg prepared and draped with foot in a steril e, translucent bag. Incisions Rutherford Morrison incision as for control of the external iliac artery and vert ical incision in groin for mobilization of femoral vessels. Procedure (see Fig. 12.20) (cid:142)(cid:3) Make an oblique incision in the iliac fossa lat eral to the edge of the rectus sheath and divide the abdominal wall muscles to expose the p eritoneum. Mobilize the peritoneum medially to expand the retrop- eritoneal space identifyi ng the ureter. (cid:142)(cid:3) Mobilize the external iliac artery and pass a sling around it for control. Now make a vertical incision in the groin and mobilize the common femoral artery, profunda femoris, and the superficial femoral vessels passing slings for control. (cid:142)(cid:3) When proximal and distal control have been achieved give the patient 5000I U heparin, apply arterial clamps to the inflow and outflow vessels and incise the aneurysm sac, evacuating thrombus and atheroma. (cid:142)(cid:3) Now sew an interposition 8mm Dacron /PTFE graft end-to-end to the distal external iliac/common femoral artery with continuous 3 /0 or 4/0 Prolene beginning in the middle of the posterior wall. If the aneurysmal disease does not involve the origin of the profunda make a similar end-to-end anastomosis to the co mmon femoral artery above the bifurcation. PERIPHERAL ANEURYSMS1 449 (A) (B) (C) Fig. 12.20 Femoral aneurysm CHAPTER 12 Peripheral vascular surgery 450 (cid:142)(cid:3) In the case of involvement of the profunda origin it may be possible to ta ilor the graft to cover the origins of both the profunda and superficial femoral or alterna tively a separate interposition graft to the profunda may be required. (cid:142)(cid:3) Check the graft for haemostasis and the limb for perfusion and close the a neurysm sac over the graft with an absorbable suture before closing the wound in layers. Popliteal aneurysm Debate continues as to the correct timing of intervention for asympto- m atic popliteal aneurysm disease. Surgery is performed for complications (embolisation or th rombosis) or rapid expansion. Approaches (cid:142)(cid:3) Medial approach \200\224most frequently used (cid:142)(cid:3) P osterior approach \200\224lazy S incision but disadvantage of separate incision for vein harvest. Position Supine as for femoropopliteal bypass surgery. Incisions As for exposure of above and below knee popliteal artery over site of previously mapped long saphenous vein. Procedure (see Fig. 12.21) (cid:142)(cid:3) Fashion incisions as above taking care to avoid the underlying long saphenous vein. Deepen the upper end through the deep fascia and deflect the sartorius musc le inserting a self retaining retractor. (cid:142)(cid:3) Expose the above knee popliteal artery and mobilize a sufficient length of the vessel as it leaves the adductor canal, passing slings around the vessel for control. The distal popliteal artery below the knee is ap- proached via a vertical incision parallel to and just below the tibia. Continue dissection between the medial head of gastrocnemius and the tibia to reach the neurovascular bundle. (cid:142)(cid:3) Mobilize the popliteal artery and a sling passed. Harvest a suitable length of long saphenous vein, between the two incisions and tunnel it orthotopically in a reversed state between the above and below knee vessels. (If no suitable vein is available use 6 or 8mm PTFE as the con- duit.) (cid:142)(cid:3) Heparinise the patient and apply arterial clamps to the popliteal artery making an appropriate sized arteriotomy. (cid:142)(cid:3) Fashion an end-to-side anastomosis of the conduit to the above knee distal superficial femoral artery. The distal anastomosis can be fashioned end-to-side/end- to-end to the below knee popliteal artery or tibioperoneal trunk. When both anastomoses are complete release the occluding clamps on the proximal and distal ends of the graft to rest ore flow in the graft and check the circulation. (cid:142)(cid:3) Remove the occluding clamps on the aneurysm and ligate the native artery p roximal to the aneurysm and proximal to the distal graft anastomosis. Close the wounds in l ayers. PERIPHERAL ANEURYSMS1 451 (A) (B) (C) (D) Vein graft with ink marks Fig. 12.21 Popliteal aneurysm CHAPTER 12 Peripheral vascular surgery 452 Pseudoaneurysms These may be iatrogenic or secondary to infection, trauma or post sur- gery and occur when there is disruption of arterial continuity with ex- travasation of blood in to surrounding tissues with formation of a fibrous tissue capsule. Indications (cid:142)(cid:3) Active hemorrhage with increase in size (cid:142)(cid:3) >3cm diameter (cid:142)(cid:3) Impending skin necrosis (cid:142)(cid:3) Pain/femoral nerve compr ession (cid:142)(cid:3) Not suitable for percutaneous closure with fibrin. Most iatrogenic are located in the femoral or brachial artery. Iatrogenic pseudoaneurysm Procedure (cid:142)(cid:3) Make a vertical incision over the puls atile mass (in the case of a femoral pseudoaneurysm proximal control may be achieved through a separate retroperitoneal incision in the iliac fossa). (cid:142)(cid:3) Enter the aneurysm sharply and evacuate the layered thrombus to reveal the vessel in the base and the pinpoint arterial defect. (cid:142)(cid:3) Control the bleeding by finger compression of the defect. Usually only one or two 5/0 Prolene sutures are required to secure the vessel. (cid:142)(cid:3) Evacuate residual haematoma. (cid:142)(cid:3) Close the wound in layers wi th a suction drain. Femoral anastomotic aneurysm Position Supine with the leg prepared and the foot in a steril e, translucent bag. Incision Repair through the previous groin incision (proximal and distal control should not be compromised and the iliac vessels may need to be exposed by an oblique retroperitoneal approach). Procedure (cid:142)(cid:3) Expose the pseudoaneurysm anteriorly via the groin incision and identify and isolate the limb of the graft above the aneurysm. (cid:142)(cid:3) Identify the native vessels if possible and free them, passing a sling aro und each to gain control. If unable to free the native vessels they may be controlled with balloon catheters from within the aneurysm sac. (cid:142)(cid:3) Give the patient 5000IU heparin and clamp the graft. Open the aneurysm sac by a longitudinal incision and insert controlling balloon catheters if necessa ry. PSEUDOANEURYSMS1 453 (cid:142)(cid:3) Oversew the orifice of the native common femoral artery with 3/0 Prolene and select a new Dacron graft of the same diameter and tailor the distal end to for m a \200\230cobra head \200\231. Suture the tailored distal end to the orifices of the sup erficial femoral and profunda vessels with 3/0 Prolene beginning at the heel and progressin g around both sides to the toe. Cut the graft to length and suture it end-to-end to the pre vious graft limb. Now release the occluding clamps and check for haemo- stasis and adequate limb perfusion. (cid:142)(cid:3) Close the wound(s) in layers. CHAPTER 12 Peripheral vascular surgery 454 Fasciotomy Indications The treatment of compartment syndrome (a group of clinical symp- tom s/signs associated with pathological increase of tissue pressure within the osseofascial co mpartments of the extremities usually following trauma or post ischaemia and involving the skeletal muscles). Signs Pain, swelling (tense) and tenderness diminished sensation. Treatment effective only if performed correctly. (cid:142)(cid:3) Lower limb requires 4 com partment release (cid:142)(cid:3) Upper limb requires 2 compartment release Procedure Lower limb (cid:142)(cid:3) Make a lateral incision in the leg one fingerbreadth anterior to the fibula and extending from the fibular head to the ankle. (cid:142)(cid:3) Divide the deep f ascia throughout the length of the incision. (cid:142)(cid:3) Make a medial incision one fi ngerbreadth posterior to the tibial border dividing the deep fascia to the ankle. Upper limb (cid:142)(cid:3) Make a curvilinear incision in the forearm extending from the a nticubi- tal fossa to the palm. The tense muscles will bulge through the divided fascia. (cid:142)(cid:3) Assess the color of the muscles/bleeding and contraction. Non-contractile non-bleeding tissue is excised. Wound management Frequent changes of non-adherent sterile dressings and delayed primary clo sure may be feasible. Alternatively skin grafting may be required to close the skin defect. This page intentionally left blank CHAPTER 12 Peripheral vascular surgery 456 Renovascular access surgery Aims Provision for dialysis access. Preoperative assessment Full cardiac history required and preoperative assessment of inflow vessels. (cid:142)(cid:3) Stenosis. (cid:142)(cid:3) Pulse volume. (cid:142)(cid:3) Consis tency of the artery wall. (cid:142)(cid:3) If absent ulnar pulse perform Allen \200\231s Te st \200\224if positive, risk of steal? (cid:142)(cid:3) Check skin for MRSA colonization. ( cid:142)(cid:3) In the obese female with little visible veins explore wrist vessels \200 \224may need to superficialise a vein. (cid:142)(cid:3) Straight configurations tend to have fewer problems than those tunneled in a curve. (cid:142)(cid:3) The preferred conduit is autogenous vein if available. Anesthesia Options include: (cid:142)(cid:3) Local anesthesia \200\224majority performed by this method (cid:142)(cid:3) Brachial plexus block \200\224adds temporary sympathectomy an d vasodilatation (cid:142)(cid:3) General anesthesia \200\224increased risk, altered pharmacokinetics in CRF . Procedure Snuff box AV fistula (cid:142)(cid:3) Make a 3 \200\2234cm incision over the anat omical snuff box and isolate the distal cephalic vein. Mobilize it and transect the vein spatulating the end. (cid:142)(cid:3) Infiltrate further anesthetic below the extensor retinaculum and mobilize the distal radial artery, dividing the small branches with diathermy or 4/0 Vicryl ties. Pa ss short segments of silk tie to act as slings and apply Yasergill/Maryfield clamps. (cid:142)(cid:3) Flush the divided cephalic vein with 20ml heparinised saline (papavarine 400mg/L) and make a small arteriotomy in the radial artery. (cid:142)(cid:3) Fashion an end-to-side AV anastomosis with continuous 6/0 or 7/0 Prolene. Check there is a palpable thrill and haemostasis is secure. (cid:142)(cid:3) Close the wound in layers with 4/0 PDS. Radiocephalic (Cimino) fistula (ci d:142)(cid:3) Infiltrate the skin of the wrist overlying the radial artery with 1% xylocaine and make a 3 \200\2234cm incision in the skin. Isolate and mobilize the cephalic vein passing a silk tie as a sling. (cid:142)(cid:3) Transect the vein distally to allow a sufficient length of vein to be swung to the radial artery taking care to avoid spiraling or twisting of the divided vein. (cid:142)(cid:3) Flush the vein with heparinised saline and apply a Maryfield clip to the vein. RENOVASCULAR ACCESS SURGERY1 457 (cid:142)(cid:3) Mobilize the radial artery dividing any small branches either with diathermy or 4/0 ties and fashion a 1cm vertical arteriotomy using iris scissors and perfor m an end-to-side AV anastomosis with continuous 6/0 Prolene. A radiocephalic fistula may be fashioned at almost any site in the forearm although the rad ial artery becomes progressively deeper in the upper arm. Brachial AV fistula (cid:142)(cid:3) Infiltrate 10 \200\22315ml of local anesthesia into th e skin of the cubital fossa from just lateral to the palpable brachial pulse laterally. (cid:142)(cid:3) Make an oblique/transverse incision in the skin to expose the superficial veins. The venous anatomy is variable but options include: (cid:142)(cid:3) End -to-side using the median cubital vein (cid:142)(cid:3) Deep perforating vein if it will re ach the artery (cid:142)(cid:3) If median cephalic thrombosed mobilize proximal cephalic to reach. (cid:142)(cid:3) Infiltrate further anesthetic and divide the deep fascia and the biceps aponeurosis to expose the brachial artery which is mobilized over a suffi- cient length and slings passed. (If high bifurcation use the radial/ulnar.) (cid:142)(cid:3) Divide the vein ligating the distal end and spatulating it proximally applying a Maryfield clip to prevent backbleeding. (cid:142)(cid:3) Apply bulldog clips to the brachial artery and fashion a 1cm arteriot- omy with iris scissors. Join the spatulated vein to the arteriotomy with a continuous sutur e of 6/0 Prolene and release the occluding clips on the brachial artery. Check the haemosta sis and for the presence of a thrill. (cid:142)(cid:3) Close the wound in layers with 4/0PDS. Basilic transposition AV fistula Th e basilic vein lies deep within the limb close to the brachial artery and is often spared f rom venepuncture or infusion injury. (cid:142)(cid:3) Expose the vein is exposed by a longi tudinal incision along the medial border of the biceps muscle extending the major part of t he length from the elbow to the axilla. The side branches are divided and the vein mobilize d throughout its length taking care to preserve the me- dian cutaneous nerve of forearm and the median nerve. Tunnel the mobilized vein subcutaneously to lie adjacent to the brachial artery or superficialise it. (cid:142)(cid:3) Apply bulldog clips to the brachial artery and divide the vein proximally and spatulate its end. Make a 1cm arteriotomy in the brachial artery and fashion an end-to- side AV anastomosis with continuous 6/0 Prolene. (cid:142)(cid:3) Close the subcutaneous tissues below the superficialised vein and close the wound in layers with an absorbable suture after ensuring the presence of a palpable thr ill in the fistula. Lower limb AV fistula The long saphenous vein of >3.5mm diameter in the thigh can be used a s a suitable conduit if there are no suitable veins in the arm. The preferred configuration is a straight transposition onto the anterior thigh. (cid:142)(cid:3) Expose the long saph enous vein in the proximal thigh through a vertical incision along the desired length. CHAPTER 12 Peripheral vascular surgery 458 (cid:142)(cid:3) Transpose the mobilized vein subcutaneously to lie over the distal superficial femoral artery in the mid to distal thigh. (cid:142)(cid:3) Expose the SFA and apply bulldog clips to the artery and fashion a 1.5cm arteriotomy. Now join the spatulated vein end to the arteriot- omy with a continuous 6/0 Prolene and release the occluding SFA clamps. (cid:142)(cid:3) Close the wound in layers. Prosthetic access grafts Indications Synthetic arteriovenous bridge if no adequate vein exi sts. The usual prosthetic material is PTFE. Requirements for a synthetic graft are suit- ab le arterial inflow and a vein to provide adequate venous outflow. A variety of anatomical graft configurations are possible: (cid:142)(cid:3) Straight radiobasilic (cid:142)(cid:3) Brachiobasilic forearm loop (cid:14 2)(cid:3) Brachioaxillary graft (cid:142)(cid:3) Thigh loop (common femoral/femoral vein). Grafts require a brief period of consolidation (7 \200\22310 days) but are prone to infecti on or thrombosis. Brachioaxillary PTFE graft Position Supine with the arm extended on a table with the hand i n a sterile, trans- lucent bag. Procedure (cid:142)(cid:3) Make a transverse incision in the axilla and mobilize the axilla ry vein passing slings around the vessel. (cid:142)(cid:3) Now expose the brachial artery at the elbow either by a vertical incision just below the edge of biceps or by an oblique cubital fossa incision. (cid:142)(cid:3) Mobilize the artery and pass slings around it for control. Using a tunneling instrument fashion a subcutaneous tunnel between the two incisions and pass a len gth of unsupported 6mm or 8mm PTFE graft along the tunnel. (cid:142)(cid:3) Give the patient 5000IU heparin and clamp the axillary vein with bulldog clips. (cid:142)(cid:3) Make a 1.5cm venotomy, tailor the graft obliquely and suture the graft to the venotomy with continuous 6/0 Prolene. Now apply bulldog clips to the brachial artery an d fashion a 1.5cm arteriotomy, anastomosing the graft to the artery in a similar fashion en d to side with 6/0 Prolene. Release the arterial clamps and check for haemostasis at the su ture line then release the clamps on the axillary vein. (cid:142)(cid:3) Close the wounds without drainage in layers. This page intentionally left blank CHAPTER 12 Peripheral vascular surgery 460 Amputations Despite use of embolectomy, arterial bypass surgery and catheter- directed thro mbolysis the annual amputation rate has not decreased, peripheral vascular disease being re sponsible for 90% of amputations performed in England and Wales. Aims Restoration of mobility, relief of pain life saving procedure. Indications Chronic ischaemia flexion contractures or non- Elderly who do not walk with rec onstructable disease (rest pain) and ulceration or gangrene affecting a considerable part o f the weight bearing surface. Acute ischaemia Limb loss following acute ischaemia is 9 \200\22330% with a mortality >18%. Ampu- tation appropriate when ischaemia fails to respond to surgical or medical measures a nd to prevent septicaemia resulting from gross tissue necrosis. Infectious gangrene (diabetics) When gangrene is \200\230dry \200\231 amputation is perfor med when there is a clear line of demarcation established. When \200\230wet \200\231 gangr ene is present, preop- erative control of infection is needed by use of antibiotics. Infect ion is usually polymicrobial and adjunctive treatment with broad spectrum anti- biotics nec essary (cephalosporins/ aminoglycosides/metronidazole).The foot is not salvageable when inf ection has destroyed the plantar architec- ture or if debridement results in no functional weight bearing surface. MRSA is today a likely problem. Level of amputation (see Fig. 12.22) Aim (cid:142)(cid:3) Remove the infected/dead part (ci d:142)(cid:3) Site with good potential for healing (cid:142)(cid:3) Successful rehabilitati on (cid:142)(cid:3) Prosthetic device fitting. Ultimate objective is to identify the most d istal site at which healing will reliably occur. Vascular reconstruction may allow healing at a lower level and better rehabilitation potential. Basic principles (cid:142)(cid:3) Careful, precise surgical technique (cid:142)(cid:3) Bone s transected at comfortable distance above skin flap (no tension) (cid:142)(cid:3) Nerves d ivided sharply (nerve catheters for analgesia) (cid:142)(cid:3) Avoid mass ligatures (cid:1 42)(cid:3) Haemostasis essential (closed system suction drains). Foot Digital amputations The flaps may be fish mouth, plantar based, dorsal based or circul ar but should be tension free to allow closure over the bone stump. Never AMPUTATIONS1 461 Amputation sites Skin flaps Transmetatarsal amputation Fig. 12.22 Amputations in the lower limb CHAPTER 12 Peripheral vascular surgery 462 carry out amputation by disarticulation through a phalangeal joint, but rather transect the proximal phalanx leaving a button of bone. Ray amputation (cid:142)(cid:3) Use a racquet incision with the vertical component on the d orsum of the foot to expose the metatarsal head and carry out incision distally to encircle the toe. (cid:142)(cid:3) Divide the distal metatarsal shaft at its neck and all the attached ten- dons and nerves. Secure haemostasis. (cid:142)(cid:3) Approximate the skin flaps are approximated accurately and without tension using non absorbable sutures. Transmetatarsal amputation Indications (cid:142)(cid:3) Gangrene of foot confined to the to es (cid:142)(cid:3) The plantar skin of the foot must be healthy. Procedure (cid:142)(cid:3 ) Make a slightly curved dorsal incision from one side of the foot to the other just distal to the anticipated point of bone division in the middle portion of the metatarsal shafts. Extend the incision at the base of the toes across the plantar surface of the foot in the m etatarsophalangeal crease. Deepen the dorsal incision down to the metatarsal shafts. (cid:1 42)(cid:3) Excise the plantar flap from the metatarsal shafts and divide the meta- tarsal bones with a Gigli or oscillating saw. The bone ends are smoothed with a rasp and th e plantar flap tailored, thinned, and redundant muscle excised. (cid:142)(cid:3) Approximate the flap and skin edges by a tension free skin closure using interrupted sutures. Postoperatively (cid:142)(cid:3) No weight-bearing for 7 \200\22310 days (cid:142)(cid:3) N o specific prosthesis required but shoe modification. Lisfranc forefoot amputation Similar to above but makes use of a short dorsal and along pla ntar flap, the bones being divided along the base of the metatarsals. Symes amputation Seldom indicated for the truly ischaemic limb but may be applicable in dia betics with forefoot gangrene. Not greatly favored by prosthetists or patients (BKA better) . A healthy heel pad is a prerequisite. Procedure (cid:142)(cid:3) The incision creates a long posterior flap incorporating the hee l pad the dorsal incision extending across the ankle from the medial to lateral malleolus. Make the plantar incision at 90(cid:13) angle to the dorsal incision and extend it in the p lantar aspect of the foot distal to the heel cutting all layers to the bone (take care not to cut the posterior tibial artery on the sole). (cid:142)(cid:3) Enter the capsule of the tibiotalar joint. Divide the tibialis posterior