Category: techniques

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acute limb ischemia bypass chronic limb threatening ischemia cli clti cost innovation hybrid technique limb salvage Practice techniques vascular lab

MacGyvering as tactical innovation -set your mind free.

The patient is a 70 year old man with risk factors of cigarette smoking, type II diabetes mellitus, hypertension, and hypercholesterolemia who presents with rest pain and gangrene of the tip of his left great toe. Several weeks prior to this, he went to his pharmacy and received a flu vaccination and picked up over the counter topical medication for an ingrown toenail. who developed pain from an ingrown toenail. Several weeks later, the tip of his toe blackened and the pain became unbearable and he came to the hospital.

No pulses, dry gangrene of tip of toe

Physical examination was notable for the dry gangrene affecting the distal phalanx of the left hallux. There was a left femoral pulse, but nothing was palpable below. His forefoot was cool and painful and this pain was relieved with dependency.

Pulse volume recording showed a drop in flow across the left knee and flate waveforms at the ankle, foot, and digits. The ABI was zero. WIfI 2 3 2, Stage 4, potential benefit of revascularization high (reference 1). CTA was performed and revealed patent aortoiliac segment, patent common femoral and profunda femoral arteries, with occlusion of the mid to distal SFA, reconstitution of the above knee popliteal artery with 2 vessel runoff via a patent posterior tibial and peroneal arteries.

CTA VR Reconstruction Shows Reconstitution of AK POP and 2V Runoff via PT and Peroneal Arteries

The centerline reconstructions, adapted from aortic planning, lets me determine the character of the arteries for size, calcification, stiffness, collateralization, and length of occlusion. This was had low density and given the timecourse of the events -from claudication to gangrene, and the lack of collaterization implying an acute process possibly on a chronic lesion, I felt there was likely to be some thrombus burden over a chronic plaque across Hunter’s Canal with occlusion of the geniculate arteries. Usually, when the occlusion is chronic, femoropopliteal occlusions of this type come with an ABI of 0.5-0.7, not 0.

GLASS FP:3, IP: 0 Stage II: Intermediate complexity disease

Global Limb Anatomical Staging System (GLASS) Classification of CLTI (reference 2) through the easy to use SVS calculator came out Stage II: Intermediate Complexity. I had the good fortune of being in the audience when GLASS was presented to a rapt audience in Lyons, France, by Dr. John White in 2017, at the ESVS meeting. I include it because Dr. Devin Zarkowsky on a tweet that generated this post wanted WIfI and GLASS. WIfI I find helpful. GLASS I am still figuring out, because it tends to tell me what I already know: this is a lesion of intermediate complexity that could go either way to open or endovascular.

Treatment options include:

  1. Endovascular -starting with POBA and escalating to various additional therapies such as stents, covered stents, DCB, drug coated stents, atherectomy, thrombectomy, thrombolysis (then any of the previously mentioned).
  2. Bypass with PTFE
  3. Bypass with vein
White Arrows Show the Excellent GSV

The data tells us so far that open or endovascular is broadly equivalent, but experience guides me. For rest pain, any incremental increase of flow will do, and it does not necessarily have to be in-line. For healing major tissue loss, there really can’t be enough flow. Bypasses with good runoff deliver a lot of flow. Bypasses with vein have great longevity and the shorter they are, the longer they last.

So is long patency important? Numerous studies have shown that patency does not impact limb salvage or amputation free survival, going to BASIL Trial (reference 3), but even stretching back to Dr. Frank Veith’s advocacy of PTFE bypass to infrageniculate targets (reference 4), patency does not add to limb salvage beyond the initial wound healing. The patency of a PTFE bypass to a tibial target is less than 20% at 5 years, but the limb salvage rate is a laudable 80% plus, and this is repeated in numerous evaluations of POBA, stents, and every new technology that has accrued in the nearly 4 decades since that paper.

What does patency buy you? Less reinterventions. There is nothing worse to me than having to reintervene within a year or two of an intervention. When a bypass works well, the patients just come for a hello-how-do-you-do for years. The BASIL trial concluded that bypass operations were more expensive, and I dispute this. In 2021, operations were far less expensive than the latest energy weapon, their box you have to purchase, and the catheters you use once and throw away. The argument given by interventionalists is that bypass operations are disfiguring and ridden with complications and that argument holds water as there are many points where vascular surgeons fail or have largely stopped work on investigating and optimizing open surgery. What if bypass surgery could be brought to the level of dialysis access surgery in terms of invasiveness? What if groin complications could be minimized? What if long filleting-type incisions of the thigh and leg could be eliminated entirely? What if edema could be prevented or minimized postoperatively to prevent serous drainage and infections? If you focus on the art of bypass surgery and choose patients well, you can get a quick, minimally invasive bypass with the overall physiologic impact of a Brescia-Cimino AV fistula. After considering endovascular, I chose bypass.

This patient had on mapping excellent saphenous vein between 3-5mm in diameter. He had excellent skin and was not obese. A vertical groin incision could be avoided by making a skin line incision over the saphenofemoral junction and transposing it to the adjacent SFA which was patent. Skin line oblique incisions in the groin heal much better than the standard vertical incisions, and it is possible to mobilize and expose the saphenous vein using an appendiceal retractor and clipping the generous proximal thigh tributary. In this patient, the most proximal incision was well away from the inguinal crease, the generator of wound infections in the groin. Essentially, if there is no groin incision there can be no groin complication.

The distal vein is mobilized first before dropping on the above knee popliteal artery which is exposed through a separate incision. This is because the AK POP space is best exposed over the sartorius, and the vein in this patient was well below (posterior) to the sartorius. The vein was tunneled under the sartorius to the AK POP. With the in-situ technique, the proximal anastomosis is completed, then the valves lysed with a retrograde LeMaitre valvulotome. Doing, after two or three passes, the pulse was strong, and the flow strong enough to fling the blood beyond the foot -a key step. If there is no such flow, if there is a weak pulse, or poor blood flight, I do one more pass of the valvulotome then duplex for any large diverting tributaries and tie them off one by one until good flow is achieved.

I do not mobilize the entire vein (and tie off every collateral) unless I cannot do an in-situ technique. It defeats the purpose of this beautiful minimally invasive procedure.

Femoral artery to above knee popliteal bypass with in-situ vein

He recovered rapidly and was discharged home after a partial hallux amputation by podiatry. In followup, he was feeling better. All of his surgical wounds had healed. Duplex and ABI did find this:

Retained valve, very hard to see but present on B-mode, causing a hemodynamically significant stenosis, with ABI of 0.57

I took him to the angiosuite for repair of this retained valve. Rarely, retained valves occur after in-situ bypasses, but require generally unsatisfactory solutions involving either open valvulectomy and patch venoplasty or stenting of a virgin vein. Valvulotomy is possible, but generally described as an open procedure as well, but I had other plans.

Downstream of this retained valve were tributaries which could be seen on duplex, and therefore accessible with a micropuncture needle. This would then allow for placement of a 4F sheath, through which the LeMaitre valvulotome would pass unhindered, allowing for valvulotomy. I would use this session in the angiosuite to deliver embolization coils to the diverting tributaries as well.

Arteriography reveals a retained valve and diverting AVF’s
Retained valve catches the catheter sent up and over from the other side

LeMaitre is a unique company in that it focuses on vascular surgical operations and arises from the original product and reason for the company the eponymous valvulotome. Because it comes sheathed in a low profile catheter, it is immediately familiar to modern surgeons even though it was made in another century.

Cutting of retained valve with LeMaitre valvulotome​ using ultrasound guidance​

Cutting the valves involved passing the valvulotome several under fluoroscopy through a 4F sheath placed through the tributary seen above. After the valvulotomy, the diverting tributaries, only one of which drained quickly into a deep vein, were coiled. At the end of the procedure, a manual cuff was found and an ABI checked. It was now 1.05.

Diverting tributaries coiled

In 2015, the Oxford English Dictionary added McGyver as a verb -“Make or repair (an object) in an improvised or inventive way, making use of whatever items are at hand.” A television show from the 80’s and early 90’s, the main character, McGyver, was able to make useful tools out of what was available, allowing him to come out victorious, but usually just survive. It is a useful concept that is a must have in managing complex and dynamic situations. Just because it hasn’t been done before to your knowledge doesn’t mean that it isn’t a simple solution. I have only one ask that LeMaitre flip their blades around and design an ante grade valvulotome. Those who know what I’m getting at know what I am getting at.

The LeMaitre valvulotome allows for in-situ saphenous vein bypass, a prototypical hybrid vascular procedure from the 80’s that portended the endovascular revolution that followed. It is meant to be used intraoperatively, but because of its low profile, it can be applied.

I will allow that this second procedure likely makes any argument to cost moot, but numerous incisions and extra time in the OR is avoided. The patient now has a vein bypass that could last many years which diminishes the need for follow up procedures to maintain assisted patency.

We will be arguing this point for years even after BEST-CLI is presented. BASIL-2 just closed enrollment. Hopefully we will get some clarity.

Reference

  1. Mills JL Sr, Conte MS, Armstrong DG, Pomposelli FB, Schanzer A, Sidawy AN, Andros G; Society for Vascular Surgery Lower Extremity Guidelines Committee. The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System: risk stratification based on wound, ischemia, and foot infection (WIfI). J Vasc Surg. 2014 Jan;59(1):220-34.e1-2. doi: 10.1016/j.jvs.2013.08.003. Epub 2013 Oct 12. PMID: 24126108.
  2. Conte MS, Bradbury AW, Kolh P, White JV, Dick F, Fitridge R, Mills JL, Ricco JB, Suresh KR, Murad MH; GVG Writing Group. Global vascular guidelines on the management of chronic limb-threatening ischemia. J Vasc Surg. 2019 Jun;69(6S):3S-125S.e40. doi: 10.1016/j.jvs.2019.02.016. Epub 2019 May 28. Erratum in: J Vasc Surg. 2019 Aug;70(2):662. PMID: 31159978; PMCID: PMC8365864.
  3. Adam DJ, Beard JD, Cleveland T, Bell J, Bradbury AW, Forbes JF, Fowkes FG, Gillepsie I, Ruckley CV, Raab G, Storkey H; BASIL trial participants. Bypass versus angioplasty in severe ischaemia of the leg (BASIL): multicentre, randomised controlled trial. Lancet. 2005 Dec 3;366(9501):1925-34. doi: 10.1016/S0140-6736(05)67704-5. PMID: 16325694.
  4. Veith FJ, Gupta SK, Ascer E, White-Flores S, Samson RH, Scher LA, Towne JB, Bernhard VM, Bonier P, Flinn WR, et al. Six-year prospective multicenter randomized comparison of autologous saphenous vein and expanded polytetrafluoroethylene grafts in infrainguinal arterial reconstructions. J Vasc Surg. 1986 Jan;3(1):104-14. doi: 10.1067/mva.1986.avs0030104. PMID: 3510323.

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bypass complications graft infection mycotic aneurysm open aneurysm surgery peripheral aneurysm pseudoaneurysm skunk works techniques

EIA pulldown transposition: another way to treat infected common femoral pseudoaneurysm

Patient with infected femoral pseudoaneurysm, skin necrosis, about to blow

A surgeon from Nepal posted a case of a ruptured common femoral pseudoaneurysm infected from IV drug abuse on LinkedIn. The comments centered around typical textbook responses which were:

  1. Ligate, debride, obturator bypass
  2. In situ bypass with femoral vein +/- sartorius flap
  3. Rifampin soaked graft or crypreserved allograft
  4. Ligate only

My preferred treatment is #2, in-situ bypass with harvest of adjacent deep femoral vein. I never liked that procedure because in general in these patients, everything bleeds. Then I had a thought -how about if you mobilize the external iliac artery in the pelvis over its entire length and pull it out from under the inguinal ligament to sew to the femoral bifurcation or SFA? That is, when you enter the pelvic retroperitoneum to gain proximal control:

The external iliac artery is usually redundant and elastic in young people

You mobilize the external iliac artery from the iliac bifurcation to the inguinal ligament, detaching the inferior epigastrics as a last step. And then you pull it out from under the inguinal ligament, and anastomose it to the femoral bifurcation or the SFA.

The mobilized external iliac artery is pulled down to reach normal femoral artery. The distance x is the length of CFA that needs replacing

This makes sense because in young people and those with AAA and minimal atherosclerosis, the external iliac artery is both redundant and elastic, making it suitable for a pull down transposition. But then, how do you know as you mobilize the artery in the pelvis that you have enough to pull down?

Pythagoras figured that out two an a half millenia ago. If you measure the straight line distance from iliac bifurcation to the takeoff of the inferior epigastric arteries, you get the straight line external iliac artery distance. The length of the common femoral artery which is the excess EIA length needed, is assigned the value x. Then the height of the stretched artery off the line between the iliac bifurcation and the inguinal ligament will determine how much extra artery you have.

Taking these values, I did some maths.

The solution for h, the height, is highlighted in yellow below. (note, the variable x in my notes is half the length of CFA, l is half the length of EIA, ie. 2x is CFA length).

Creating a spreadsheet for CFA lengths from 2 to 6cm and EIA straight distances of 5-10cm, the ratio of height H to CFA length varies from a minimum of 0.7 to maximum of 1.7 with an average of 1.1. That means the majority of the time, if you get 1.5x the length of CFA height off the pelvis, you should reach.

If you are short, you can detach the profunda and mobilize the SFA, pulling upwards, then reattach the PFA. Though this is entirely a thought experiment, there is no reason why it should not work. As with most things, I predict that it already has been done!

The advantages are using autologous tissues and leveraging the natural anatomy. There is a cost benefit in that OR time is shorter with less time for venous harvest and avoiding grafts, patches, and devices. The patient would avoid ischemia as would happen in the staged repair. The disadvantage is when you are short, but if you mobilize the appropriate amount (height off pelvis at least 1.5x the CFA length) you should be okay. The more curvature and tortuosity seen on 3DVR recontstruction and absence of significant atherosclerosis would predict feasibility.

Categories
AIOD aortoiliac occlusive disease (AIOD) bypass complications cost innovation graft infection techniques

The Story Should Fit: Repair of a Stent Graft Infection with Aortoiliac Endarterectomy and Bovine Pericardial Graft

One of the greatest surgical texts, Cope’s Early Diagnosis of the Acute Abdomen, is something every surgical resident, vascular or general, should read. The mid-century edition which I owned during my residency, has since been updated, but the central message of the book is this: every complaint or pain the patient has comes from a nerve, either peripheral or visceral, and understanding the nature of the pain, you narrow the diagnosis to only a few possibilities. Irritation of the psoas muscle results in a characteristic pain that years of diagnosing appendicitis the old fashioned way -by exam, then operation, makes it easy to recognize, like Marilyn Manson showing up as your substitute teacher (I would have said Alice Cooper, but that completely dates me). When the psoas muscle is irritated, by a hematoma, injury, inflammation, or abscess, the muscle relays intense pain localized to the retroperitoneum. Stretching the muscle worsens the pain, and the patient is often seen with the ipsilateral hip flexed. The genitofemoral nerve which rides on top of the psoas, is triggered and there is pain referred to the groin and proximal anterior thigh. Seeing this, and fitting the story allows for a diagnosis, before imaging. Without this insight, there is no swift vector to treatment and resolution.

Patient with inability to straighten left hip after iliac stent placement

The patient, a middle aged man, had undergone a redo-iliac angioplasty and stent for left iliac in-stent restenosis. He relayed that on the table, he felt immediate left lower quadrant abdominal pain and the desire to flex his left hip. He was restrained, sedated, and the procedure finished -a covered stent had been placed. When he came to my office a month after his initial procedure done elsewhere, he was in wheel chair, unable to straighten his leg. He claimed before coming to see me, he had gone to another hospital, where he had a CT scan and was told nothing was wrong (will have to confirm). He was having subjective fevers at home.

On examination, he sat on the exam table with left hip flexed. His pedal pulses were easily palpable. He had furuncles in his groins which he relayed he had had all of his life. I sent him for CTA and subsequently admitted him for surgery.

left iliopsoas abscess

The CT showed a large collection around the left iliac artery and stents and on the psoas muscle, an abscess. The blood cultures on admission were positive for Staphylococcus lugadensis sensitive to penicillin.

Putting the story together after the fact is much easier than when you are in the moment, but being aware of the location and type of pain should give you a clue. Very likely, he had a brief rupture on the angiosuite table resulting in his sudden pain, drowned out by the sedatives typically given in response to a patient moving when a stent is deployed. Inflating a balloon in an artery typically causes some discomfort -as the vessels are lined with visceral nerve fibers which are quite sensitive but less localizable than say a pin poking on the index finger. If you ever had bloating with gas, that general discomfort localizable to the mid abdomen, that nausea and discomfort is from stretched visceral pain fibers. If you have ever had dull aching pain of distended spider veins, that is visceral pain. It’s there, but you would not be able to pinpoint it exactly. That is not what this patient had when he flexed his hip on the angio suite table. While the covered stent was deploying, he likely briefly ruptured causing both somatic and visceral pain around his left common iliac artery and iliopsoas muscle. Additionally, if the sheath had been entered through an area of a skin abscess, likely the sheath, wires, and gloves were contaminated. Any handling of the balloon expandable stent graft, which I highly discourage, would have contaminated it, resulting in a device infection, which was made more likely due to his diabetes. As the hematoma got infected, it resulted in the worsening symptoms he was having of left lower quadrant abdominal pain, groin pain, thigh pain, and inability to straighten his hip without pain.

I took him to the operating room and drained his abscess, assisted by Dr. Andrew Tang, chief resident headed to CT Surgery fellowship here at the Clinic, and Dr. Jenny Chang, PGY 2 Surgery. I gave Dr. Chang a copy of Cope’s with the admonition to read it soon and pass it on, as most of the current generation claim no knowledge of this important text. While I am not against interventional drainage, it takes time to drain the collection through a tube whereas sticking your hand in, sampling the collection, observing the injury, and breaking up collections and washing out with brown-bubbly -a mix of betadine/peroxide diluted in saline, I believe speeds the recovery from the infection. His drainage was done through a retroperitoneal approach from the left side and notably, his psoas muscle while viable, did not retract to cautery energy, suggesting some degree of rhabdomyolysis. The iliac artery was an indurated, thickened, and hard from the calcium and plaque that was the original problem affecting his distal aorta and iliac arteries (see left arteriogram centerline). I placed a pair of JP drains, removed one that wasn’t draining much on POD #3, and the other about a week after discharge on POD#5. His WBC elevation which was never high promptly resolved. I kept him on oxacillin with consultation from ID, and waited. After 3 weeks, I repeated his CTA.

His right iliac centerline showed patent stent with diffuse plaque and calcium starting in mid infrarenal aorta.

His abscess had significantly resolved and his pain was gone. He was ambulating again.

Before and after abscess drainage

The choices at this point were the following

  1. Continue treatment of patient with supressing antibiotics for life
  2. Resection of left iliac stent graft which is presumed to be infected

If resection chosen, the options for repair that I considered included:

  1. NAIS (ref 1). Neoaortoiliac System graft using femoral vein
  2. Aortoiliac homograft
  3. Rifampin soaked gelatin coated graft (ref 2)
  4. Extra-anatomic bypass with axillofemoral bypass or femorofemoral bypass.
  5. Aortoiliac endarterectomy and repair with bovine pericardial patch and graft

The choice of replacement is becoming clearer in that while rifampin soaked grafts offer immediacy and expedience, all grafts seem to be prone to reinfection at a higher rate than autologous material (ref 3). The NAIS bypass is a great option, but is hampered by the addition of several hours invested in harvest of the femoral veins. While it can be staged with mobilization done one day and harvest another, those added hours add complications. We often forget that the simple metric of procedure time is the most important determinant of complication rate. Any operation going over 2 hours risks wound infection for example simply from ambient colonization of the open wounds from the rain of dead skin from the surgeon’s face, aerosolized fecal flora from flatii (prohibited in my ORs). The microenvironment of the open wound is also room temperature and not 37, having an impact on organ function and hemostasis. The homograft is the original aortic graft -before Arthur Voorhees invented the cloth vascular graft as a resident at Columbia P&S (my medical school alma mater, ref 4), major hospitals had tissue banks of aortic homografts harvested from the recently deceased. Having homografts is now an outsourced function, but does require having proper refrigeration for the cyropreserved grafts and generally can’t be ordered with short notice.

Rifampin soaked grafts work well, especially wrapped in omental flap, in the short and medium term but suffer a reinfection rate that is higher than seen with autologous tissues, and prosthetic grafts without rifampin, such as PTFE for extraanatomic bypass, have the highest rates of reinfection (3), despite being the board answer decades ago.

Endarterectomy allows for use of native tissues for repair. The adventitia around plaque and stents, while thin, can support physiologic pressures, even when they have been occluded for years. And while practice of aortoiliac endarterectomy is a bit of a lost art, it has both a long history stretching back nearly a century and a modern track record with carotid and femoral endarterectomy. It is merely a matter of scale. Pinch and zoom in on a femoral endarterectomy at the bifurcation and you have the same case as with an aortic one.

The question is, is bovine pericardium more autologous than prosthetic? It is a decellularized sheet of collagen from a cow’s pericardium, used in heart valves and vascular patches, but only recently applied as a graft (ref 5-7). I have long used bovine pericardium as a patch with some caution, but the rule of thumb is are there well vascularized tissues around it? A layer of Scarpa’s fascia and fat in a groin wound are not sufficient to protect a bovine patch, but a sartorius flap is. For me, once the infected stent graft is out, knowing if the surrounding tissues bleeds well is an important one.

I chose to do aortoiliac endarterectomy. The patch and graft would be made with bovine pericardium, unless I found the left iliac segment to be devitalized and foul with anaerobic vapors, then, I would close and go NAIS or extra-anatomic. The key point is that choices have to be on the table and constantly rearranged during the conduct of the operation.

The patient was preoperatively vein mapped and had suitable deep femoral vein for bypass conduit, having robust duplicated systems that would impact the patient minimally. The patient was placed in a supine position and via a midline laparotomy, the infrarenal aorta and the common iliac arteries beyond the short iliac stents exposed. I chose this limited exposure as any further into the phlegmon on the left risk injury to ureter and vein. The aorta had a palpable demarcation between plaque and mildly diseased proximal segment, predicted by the CTA to be at the IMA. A longitudinal arteriotomy was created on the right side from mid aorta to mid right iliac, and the left side had a separate arteriotomy to release the stent. The plaque came out in a single specimen (image).

The exposed stent is the left iliac stent holding within a stent graft.

The left iliac artery was destroyed by the infection but the tissues around it bled avidly and were not foul or infected. I avoided excess debridement here as the iliac vein was intimate with the phlegmon. There was a 3cm gap. Again, I thought briefly about taking femoral vein, but proceeded to make a graft from the bovine pericardium. This was sewn around the rod portion of a renal vein retractor from the OMNI set. The finished product resembled Voorhees’ graft. It was sewn into the orifice of the iliac from inside the aorta and end to end to the freshened iliac stump. Unfortunately, the omentum was atropic across the transverse colon, but the tissues around the resected artery and stent graft bled well, indicating good penetration of antibiotic. The retroperitoneum was closed after hemostasis obtained. Dr. Shashank Sharma, our chief resident headed to a vascular surgery fellowship at the renown Houston Methodist next year got to see what is unfortunately a rare occurrence -an aortoiliac endarterectomy, which through me puts him three degrees of separation from Cid Dos Santos (ref 8). Dr. D’Andre Williams, PGY-2 Vascular Surgery Resident, got important lessons on sewing the aorta. She’s part of a fortunate cohort that get exposed to open aortic surgery at our main campus which is unfortunately rare throughout the world.

The pericardium was soaked in rifampin, but probably did not bond to the collagen.

The final graphic shows the operative end result.

The patient recovered well and was discharged within the week with another month of IV antibiotics planned.

Before and After

Conclusion: The operation was started at 8 in the morning and was done by lunch time. For aortic cases, this is a crucial metric, as when the clock winds past the surgeon’s comfort, the patient suffers even more. Adding the femoral vein for a NAIS may have been the textbook thing to do, but we don’t do extra-anatomic bypasses that much either. I don’t believe that adding two more hours for retrieving the femoral vein would have enhanced the procedure, and would have served to add potential areas for complication. Technically, the aorta closes much as with a carotid or femoral endarterectomy, but the adventia is thin and really should be sewn with 5-0 or 6-0 Prolene. The larger needles such as the SH size creates unnecessary bleeding unless sewn with a line of felt which could become infected. Despite the thinness, it will hold pressure if it is not infected. Clamps that bend out of the “airspace” above the laparotomy, such as the Cherry Supraceliac Clamp and Wiley Hypogastric Clamp, prevent limiting the operative space with long clamps such as aortic Fogarty or DeBakey clamps, while being stronger than the Zenker.

A final comment for Staphyloccocus lugudensis. This is the second major vascular graft infection with this organism I encountered this year. The other was an infected aortic stent graft. Lugudensis means from Lyons. I do not know why that is, but it is so far not the nasty player that is S. aureus. I am sure it will share some plasmids, and become resistant one day, but in the earlier case in Abu Dhabi and now this, it is sensitive to penicillin, and came from the skin at the femoral puncture site, and for this we are fortunate. Major vascular infections are one of the few areas that still demand open surgical skills, and we foresake them at great peril. It’s critical to remember all the collective memory of surgery from the past, or we will become mere technicians fixing whatever comes out of the radiologist’s report with whatever knowledge obtained from a Zoom meeting for the latest, greatest device.

Acknowledgement

Gratefully, the patient gave his permission, as with all patient, for use of his case for educational purposes.

References

  1. Chung J, Clagett GP. Neoaortoiliac System (NAIS) procedure for the treatment of the infected aortic graft. Semin Vasc Surg. 2011 Dec;24(4):220-6. doi: 10.1053/j.semvascsurg.2011.10.012. PMID: 22230677.
  2. Oderich GS, Bower TC, Hofer J, Kalra M, Duncan AA, Wilson JW, Cha S, Gloviczki P. In situ rifampin-soaked grafts with omental coverage and antibiotic suppression are durable with low reinfection rates in patients with aortic graft enteric erosion or fistula. J Vasc Surg. 2011 Jan;53(1):99-106, 107.e1-7; discussion 106-7. doi: 10.1016/j.jvs.2010.08.018. PMID: 21184932.
  3. Smeds MR, Duncan AA, Harlander-Locke MP, Lawrence PF, Lyden S, Fatima J, Eskandari MK; Vascular Low-Frequency Disease Consortium. Treatment and outcomes of aortic endograft infection. J Vasc Surg. 2016 Feb;63(2):332-40. doi: 10.1016/j.jvs.2015.08.113. PMID: 26804214.
  4. Smith RB 3rd. Arthur B. Voorhees, Jr.: pioneer vascular surgeon. J Vasc Surg. 1993 Sep;18(3):341-8. PMID: 8377227.
  5. Almási-Sperling V, Heger D, Meyer A, Lang W, Rother U. Treatment of aortic and peripheral prosthetic graft infections with bovine pericardium. J Vasc Surg. 2020 Feb;71(2):592-598. doi: 10.1016/j.jvs.2019.04.485. Epub 2019 Jul 18. PMID: 31327614.
  6. Lutz B, Reeps C, Biro G, Knappich C, Zimmermann A, Eckstein HH. Bovine Pericardium as New Technical Option for In Situ Reconstruction of Aortic Graft Infection. Ann Vasc Surg. 2017 May;41:118-126. doi: 10.1016/j.avsg.2016.07.098. Epub 2016 Nov 27. PMID: 27903471.
  7. Belkorissat RA, Sadoul C, Bouziane Z, Saba C, Salomon C, Malikov S, Settembre N. Tubular Reconstruction with Bovine Pericardium Xenografts to Treat Native Aortic Infections. Ann Vasc Surg. 2020 Apr;64:27-32. doi: 10.1016/j.avsg.2019.10.104. Epub 2020 Jan 10. PMID: 31931127.
  8. Barker WF. A history of endarterectomy. Perspectives in Vascular and Endovascular Therapy. 1991;4(1)1-12. doi:10.1177/153100359100400102
Categories
taaa tbad techniques thoracabdominal aortic aneurysm type b aortic dissection visceral malperfusion

Something new in open thoracoabdominal aortic aneurysm repair

Our debranch first technique described by Dr. Niranjan Hiremath and was presented at CX Aortic in Vienna in October. Hoping to collect multicenter experience with this technique.

Categories
techniques thoracabdominal aortic aneurysm type b aortic dissection

Video of TAAA case using debranch-first technique.

www.linkedin.com/posts/w-park-565310a_clevelandclinicabudhabi-activity-6849686801343369216-2cxD

Link to original blog article regarding this case

Link to journal article.

Categories
Commentary cost innovation ECMO opinion skunk works techniques type b aortic dissection ultrasound vascular lab visceral malperfusion

5 innovations, 4 years and how cost innovation must save healthcare

At CCAD, during my 4 years here as chief of vascular surgery, I had the privilege of working with excellent colleagues in a world class facility in an amazing and generous host nation. Over that time, our operative case volumes grew rapidly (figure below) as we proved our worth.

Our unique situation as both a main campus of Cleveland Clinic and a startup in 2015 with a fraction of the systems already in place at Cleveland made innovation a necessity. When making do became making great, we achieved the world class results as we were tasked to do. I count 5 off the top off my head in vascular, but there are many more that we do every day, contributed by all the team members. It is in the Cleveland Clinic’s DNA, from its origins century ago in the vasty fields of wartime France, this systemic mission to make things better. I think a lot of how our founders worked from necessity near the trenches in operating theaters within tents, sleeping on rough cots, thousands of miles from Cleveland. It is working in a startup hospital here, a stunning facility endowed by the Emirate of Abu Dhabi, that I realized that practical innovations were the lifeblood of hospitals in times past, and that it continues to have meaning when lives are saved. In a world where costs, not ideas, will, or skills, limit the availability of healthcare, cost innovation will play a large role in its salvation.

Innovation #1: Debranching Thoracoabdominal Aortic Aneurysm

The thoracoabdominal aortic aneurysm (TAAA) is the most challenging operation to do either with open or endovascular approaches because of the complications associated with the procedure including bleeding, kidney failure, spinal cord ischemia, and death. You really can only get good by doing a lot of these regularly, as it brings with it precious experience for the OR, ICU, rehab, and floor staff. The patients with TAAA presenting to CCAD do not always have the opportunity to travel to one of the acknowledged aortic centers (with which each of the faculty here have close ties), and we must offer results that match those other centers. To me, the biggest hassle and source of complication with an open TAAA repair is the drying up of bleeding at the end of the case, the result of long visceral clamp times. Long procedure time prolongs the case and exposes the patient to a more turbulent and prolonged recovery and higher risk.

Endovascular repair with branched or fenestrated stent grafts offers one solution in avoiding the thoracoabdominal exposure and long procedure times. Unfortunately, a significant minority of patients do not have the anatomy for endovascular approaches. We have the skills, staffing, and facilities to offer both approaches, but are handicapped by low volume. Review of our volumes show that aortic aneurysm disease is dwarfed by diabetic circulatory problems. So to offer these patients the same results with open aortic surgery as the patients I had at main campus in Cleveland, I had to cheat a bit by rearranging the deck. How so? By turning the highwire act of thoracoabdominal aortic aneurysm surgery and turning into a deliberate walk on a low balance beam. By debranching the visceral branches from the graft one by one, the visceral ischemia time is minimized (video) or largely eliminated.

I discussed this with Dr. Niranjen Hiremath, our aortic trained clinical associate and like all things in medicine, a similar concept was applied by his mentor, Dr. Matalanis in Australia, to the aortic arch. We have performed two of these and both patients survived and are doing well, including the most recent one with a hybrid extant 2 repair. We published the technique after the first case in Journal of Thoracic and Cardiovascular Surgery (figure below, reference 1). I also presented the first case on this blog (link). More gratifying are the reports of adoption of this technique around the world. The patients come out of the operation without the torrent of coagulopathic bleeding seen with the traditional technique.

Innovation #2, The Vascular Lab in Every Patient’s Room

One of the things that happened early in my tenure was realizing how limited the tools available for vascular assessment were for non vascular caregivers. Both the physical examination with pulse palpation and pulse Doppler examination are challenging to master and usually fail to answer the simple question: is there enough perfusion? The absence of a pulse or Doppler signal in the hands of a non-vascular caregiver is an inconstant thing, and various projects have been undertaken that do not specifically address the triage gap that vascular surgery has compared to cardiology for chest pain. Not all chest pains are referred to cardiology. Only those those patients who pass the screening test of EKG and serum troponin levels are referred. My first inclination was to budget for pulse volume recording machines to be located in the ED and ICU’s of the hospital, but it was not a simple solution and would require stretching the limited vascular lab staff. Then it dawned on me that the toe waveforms offered a solution. On the PVR machines, the toe waveforms are captured by transmitting red laser light through the nail of the toe. A receptor captures a waveform (figure below) that is reflects the passage of blood that absorbs that red light.

This is in fact the identical technology in a pulse oximeter which has extra circuitry to calculate an oxygen saturation. I was not interested in the saturation, but rather the waveform. It turns out, for all practical purposes, the waveform given by pulse oximeter units is qualitatively the same as that given by the pulse volume recorder’s digital plethysmograph (figure below).

So now, when I get a phone call from the ED that a patient has no DP or PT pulse, I ask the caller to place a pulse oximeter with a waveform trace on the patient’s second toe (or nearest extant toe). I then ask, is there a waveform? The presence of a waveform, no matter how dampened, means the patient does not face acute ischemia, and can safely wait until the morning, avoiding a drive in the middle of the night (figure below, severely dampened waveforms).

an abnormal DPPG captured with a hospital ICU pulse oximeter

We are validating this with a study that has completed data collection and hope to present this simple test to a broad audience. This is something akin to having a point of care vascular lab study that can answer a simple question: is there blood flow at the level of the toes? The finer points of “how much blood flow” can be answered by formal testing but that keen absence of broad vascular assessment skills among healthcare providers and absence of a simple test like an EKG for MI will feel less sharp, particularly because of the near universal availability of a pulse oximeter with waveform display throughout most hospitals.

Innovation #3: Assessing for Visceral Malperfusion before Surgery for Aortic Dissection

The typical scenario for a sad ending is this: a patient undergoes emergency surgery for an ascending aortic dissection. The operation ends in the middle of the night. The morning labs show a lactate of 10 which had been rising since the end of the operation from a high borderline level of 2. The urine output also dropped to zero. The patient remains intubated and has palpable femoral pulses, but now has a distended abdomen full of bowel gas, and is unable to report pain. The decision is made to get a CTA on top of the ones the patient received preoperatively which nearly guarantees permanent renal failure and need for hemodialysis. The descending aortic portion of the dissection is noted to be causing a malperfusion of the SMA and left renal artery, and there is pneumatosis of the small bowel through transverse colon which are resected after revascularization. The patient recovers with a jejunostopy and lifelong TPN and hemodialysis. This sad scenario is what I thought about when I was asked to assess a patient intraoperatively without a femoral pulses after an aortic dissection for possible visceral malperfusion. The question was if CT with contrast was indicated. Having an RVT credential (I’m old), I frequently do my own scans, and have found under general anesthesia, the abdomen is easy to scan well. The patient is typically prepped from neck to toes for the operation, so sliding in with an abdominal probe was simple. It is possible to get excellent windows on the visceral segment abdominal aorta with long axis and short axis views of the celiac axis, SMA, renal arteries, and iiac and lower extremity arteries (figure below).

At CCAD, the patients also get a TEE, and the arch and descending thoracic aorta is well visualized. That first patient underwent a femorofemoral bypass for the lower extremity malperfusion, and I found that the left renal artery had obstruction, but the right did not. The patient was reassessed at the end of the case and good visceral perfusion was seen at that point. I realized I was onto something, and whenever possible now for ascending aortic dissections, myself or the vascular tech is called to evaluate the visceral and lower extremity arteries at the beginning of the case, avoiding contrast studies. We are submitting the experience as an abstract for the STS conference.

Innovation #4: Retrograde tibial artery distal perfusion cannulas for ECMO

This past year, ECMO has been lifesaving for many patients facing cardiovascular collapse from COVID and other conditions. Once the cannulas go in, a hypoxic patient in heart failure has a chance at recovery. The drama of the moment causes the caregivers to overlook the fact that up to 10 percent of patients without a distal perfusion cannula will develop leg ischemia, and that after 6 hours, irreversible will occur leading in neuromuscular death and limb loss. This has happened for two patients transferred for care this year. The problem is that the skill of placing a antegrade femoral artery distal perfusion cannula in the proximal thigh is not always present, and the ability to judge perfusion is degraded with ECMO flow. While older patients on ECMO may have significant arterial disease, young patients generally do not, and I saw that as an opportunity for simplifying the distal perfusion cannula by placing a 5F micropuncture sheath into the dorsalis pedis artery (figure below).

The distal perfusion cannula is in the dorsalis pedis artery

This provided sufficient flow to avoid limb loss in a series of patients on which we published a technical article (reference 2) and presented. The retrograde access of these supericial vessels is within the technical envelope of most intensivists and cardiologists, those who most frequently place emergency ECMO cannulae. It was gratifying to catch up with one of my first patients who walked in with both legs, having undergone a heart transplant while bridged with ECMO.

Innovation #5: Park Clamp Used in Thoracoscopic and Laparoscopic Surgery

The Park Clamp (link) is a circular compressor that is intended to compress bleeding tissues allowing for suturing within the circle. I invented this while at main campus, and missing it sorely, had two custom made at the prototyping facility at Cleveland Clinic and shipped into CCAD. It is particularly useful in venous bleeding during spinal exposures, redo groins around the profunda, and retroperitoneal tumor resection. Dr. Redha Souilamas, chief of thoracic surgery (image above) found it particularly useful in thoracoscopic pneumonectomies, when staple line bleeding is encountered on the pulmonary artery (image below).

Pulmonary artery staple line bleeding controlled, ready for suturing.

In laparoscopic surgery, it is possible to introduce the compressor via a small incision and this will allow for laparoscopic suturing of a vascular injury in a bloodless field. I was able to resect an IVC tumor thrombus with Dr. Waleed Hassen using this device to achieve hemostasis. The critical feature of the Park Clamp, lacking a manufacturer, is that we made it ourselves in our own hospital.

Conclusion: a modest proposal or how cost innovation will save health care

Inventions and innovations exist in a vacuum unless they are implemented, and this requires the will to accept the possibility of a better way. You should never be satisfied with the status quo if there is harm to be reduced. There has to be buy in from everyone involved or you get the situation I had when I was a PGY-2 in 1995 in the ICU. Being the surgical ICU resident, I was called nearly hourly to change the dressing on a patient with HIV and necrotizing pancreatitis with an open abdomen. There was over a liter an hour of exudate soaking the dressings and pads, making it a nightmare for the nurses. After a third round of this and feeling it would interrupt lunch, I came upon a plan for covering the wound with lap pads, overlaying a chest tube, and sealing everything with an Ioban. With the chest tube to negative pressure via a Pleuravac, the calls to change the patient’s dressing ceased, and the nurses no longer hand to change the bedding hourly -bedding that was soaked with HIV positive exudate. I was very pleased about this until I was stat called to the director’s office. I was given the dressing down of my life -how dare I experiment on his patient and didn’t I think that placing a suction on the transverse colon would result in a fistula? I hung my head in shame and took down the dressing. Of course, readers will know that this preceded the VAC dressing by about a decade, and negative pressure wound therapy is now a multi-billion dollar industry. What it teaches me to this day is that progress only happens when success is actually seen by everyone, but also there has to be buy-in from the stakeholders -the people who bear responsibility for any bad outcomes -fistula and death in the case of this proto-VAC dressing. Without convincing everyone, there is no success, and the invention goes off to die.

The fact is, one time early in my tenure here at CCAD, we ran out of negative pressure pumps, and I placed this chest tube/Pleurevac dressing on a patient with a large groin wound that was leaking high volumes of exudate and lymph. After two days, when a VAC pump became available, the patient’s groin turned out to be clean and granulating and it came to me that the next great leap in innovation is low cost innovation.

Cost Innovation, to name it, is using what is available, sometimes repurposing, or at others, dialing back the clock, to replace costly things that threaten to break a hospital’s finances while maintaining quality. It was only a few generations ago when hospitals were self contained communities. Rather than use peel packs of disposable gowns and drapes, there were tailors, seamstresses, and launderers making and maintaining the same. The Mayo Clinic was making its own insulin after discovering it and gave away the recipe out of concern for ethics -out of believing it is wrong to profit from a life threatening condition. We have the technology and capacity to make low cost endoscopes and reprocess them -possibly undercutting current costs by a factor of a thousand. We slaughter millions of hogs and cows annually, but harvest no heparin from them in the US. Laser CNC cutters, 3D printers, and enthusiastic makers have proliferated and could make every item that we currently open from a peel pack, use once, and discard into landfills -one only has to look at the cottage industry of face shields and hand sanitizers that bloomed last year during the pandemic. Pharmacists are fully capable and trained to manufacture custom pills and compound salves and solutions by the gallons if only if they are allowed to, saving hospitals millions in cost of medications sold in blister packs and tiny tubes and bottles. Stents can be printed in-house, and stent grafts can be custom made (link). Every town or city has tradespeople who can work stainless steel, plastic, and glass, or make and program custom computers -it is a short jump to making medical equipment at scale in your hospital.

Cost innovation is the only way out for the inflationary cost cycle that has throttled healthcare throughout the world. We have become a world where healthcare is delivered out of peel packs and million dollar investments to perform single procedures is considered normal and desirable, almost to the point of thinking people as coming in disposable peel packs. When I watch shows about hospitals a century ago, such as The Knick, I don’t guffaw at the old-timey medical stuff. I see a fervent environment of innovation in purposeful communities of specialized workers within hospital walls. We need to return to such practicality if we are to break out of the plastic peel pack.

References

  1. Hiremath N, Younes H, Aleinati T, Park WM. Open repair of extent-III thoracoabdominal aortic aneurysm using a modified branch-first technique. JTCVS Tech. 2021 Mar 13;7:29-31. doi: 10.1016/j.xjtc.2021.03.014. PMID: 34318197; PMCID: PMC8312144.
  2. Göbölös L, Hogan M, Kakar V, Raposo N, Sänger S, Bhatnagar G, Park WM. Alternative option for limb reperfusion cannula placement for percutaneous femoral veno-arterial ECMO. Perfusion. 2021 Mar 26:2676591211003282. doi: 10.1177/02676591211003282. Epub ahead of print. PMID: 33765883.
Categories
median arcuate ligament syndrome opinion peripheral aneurysm techniques

Nonoperative management of median arcuate ligament syndrome (MALS)

The patient is a young woman who presented with classic symptoms and findings of median arcuate ligament syndrome (MALS). She avoided food because eating triggered severe pain in her upper abdomen. Over a year, this resulted in 15 pounds of weight loss. As a result, she no longer had the energy to work or exercise. She had an extensive gastrointestinal workup including blood work (LFT’s, amylase, cholesterol panel), abdominal CT scan, and upper endoscopy which were normal except for the finding of narrowing of the celiac axis due to compression by the median arcuate ligament. Examination was notable for upper abdominal pain exacerbated by pressure and seated, hunched-over posture. Unfortunately, due to her health insurance, surgery was not covered and she did not want any. So I recommended she try the following. 

  1. Eat standing up with good posture, shoulder back, back arched, taking deep breaths and holding once food passes
  2. Practice upward facing dog yoga pose (figure) 5 reps daily with deep inhalation breath holds. If this is difficult, do this standing up. 
  3. Improve the posture during seated work, never hunch over and pressed forward with “shrimp back,” periodically take a deep breath and hold with excellent posture. 
Upward facing dog yoga pose -shoulders square, outward collar bone tension, with deep inhalation breath holds

Over the past several years, I’ve noted that most patients respond to this, even in acute MALS pain situations (yes, there is acute MALS like slipped discs, for another post). That patient came back a few weeks later reporting that she was able to eat more food, more frequently. She also acknowledged compliance with the exercise and postural adjustments at work. A month later she reported regaining her lost weight and only mild pain with sitting in a car for a long time. She was still eating standing up, and she was grateful for having been treated without surgery.

From reference below, a mechanism for celiac plexus compression, injury, fibrosis, and development of neuropathy

We have postulated that MALS is a nerve compression syndrome of the celiac plexus by the median arcuate ligament (reference). There are two consequences to MALS, neither of which is mesenteric ischemia. The first is this compression of the celiac plexus with injury resulting in inflammation and fibrosis, resulting in further compression and a neuropathy of the celiac plexus. This neuropathy triggers aberrant pain sensations in response to eating. The other consequence is remodeling and injury due to arterial compression. The celiac axis can develop post-stenotic dilatation, growing large enough to be considered aneurysmal. The compression can damage the intima resulting in dissection. The artery can be injured and a pseudoaneurysm can develop. Finally, the aneurysmal segments may develop thrombosis and be the source of thromboembolism, usually to the spleen. Even when the celiac axis clots off, unless there has been resectional surgery such as a Whipple or splenectomy, the stomach gets enough collateral flow that ischemia is rare when celiac axis occlusion occurs. So similarly to  thoracic outlet syndrome (TOS), there is a neurogenic MALS and an arterial MALS. 

The first line of therapy in neurogenic TOS is physical therapy. With symptomatic MALS, I wondered if there could be physical therapy as well. This young woman and others I have managed nonoperatively suggests good response in some,  and partial response in most to exercises and maneuvers designed to address the compression.

Currently, in lieu of celiac plexus block, I have patients treat their MALS nonoperatively using the above protocol  for 2-4 weeks, typically while they undergo further workup to rule out more common gastrointestinal etiologies of their abdominal pain, and many have been able to improve their circumstances with these measures alone. This patient chose not to have operation as she was able to live symptom free and regain lost weight with these recommendations alone. 

Addendum

I received a comment from Ms. Suzanne Peek, president of the National MALS Foundation, who correctly pointed out not everyone presents in this way. I agree each patient undergoes a unique journey that is often marked by diagnostic delays because this is a rare condition. As I stated, not every patient responds to this regimen and after work up typically will undergo surgery to which in our published results 85% have a positive response to when diagnosed with MALS. Is certainly an area of further study to see if more people can respond to this non-operative approach. Our previous protocol which we instituted after the publication of our report was to use celiac plexus blockade as a diagnostic study and occasionally permanent blockade as therapy for those with prohibitive operative risk. A positive response to this regimen may signal a positive response to surgical celiac plexus ablation.

Reference

Weber JM, Boules M, Fong K, Abraham B, Bena J, El-Hayek K, Kroh M, Park WM. Median Arcuate Ligament Syndrome Is Not a Vascular Disease. Ann Vasc Surg. 2016 Jan;30:22-7. doi: 10.1016/j.avsg.2015.07.013. Epub 2015 Sep 10. PMID: 26365109.

Categories
AAA Commentary common iliac artery aneurysm complications CTA EVAR innovation ruptured AAA techniques training

Lifelong surveillance after EVAR -is it worth it?

About ten years ago, I had a patient who came to see me for moderate carotid disease. While his carotid disease was asymptomatic, he also had metastatic colon cancer. With colectomy, cryoablation of liver mets, and chemotherapy, he was in remission. Every 6 to twelve months he had some kind of CT scan with contrast. His renal function was poor and this was blamed on his chemotherapy. While it had nothing to do with this patient, I thought to myself, “Having an aortic stent graft was a lot like having metastatic cancer in remission.” After a stent graft, the patient is forever tied to the health care system. Without surveillance, there may be an endoleak, sac expansion, rupture, and even death. Patients and vascular surgeons can make choices that lengthen life, improve its quality, and avoid the complications of disease. But what if a treatment becomes a condition and a burden on healthcare resources and the patient’s finances?

Fool me once…

Type Ib Endoleak Causing re-Rupture of a previous r-AAA after no surveillance

Take this patient who had previously ruptured his AAA and undergone EVAR. Several years out from his rupture, he ruptured again from a type Ib endoleak due to aneurysmal degeneration of his right common iliac artery. Per his family, he never followed up. Perhaps he assumed he was cured of his disease? Repairing this was tricky, primarily because I hopped up and down, thinking, “I could cure this!” An open revision with a bifurcated graft would eliminate the need for EVAR surveillance, avoid abdominal compartment syndrome, and the physiologic consequences of a large retroperitoneal hematoma. But who wants a laparotomy? Not this patient, who was hypovolemic shock, and whose family chose the minimally invasive option that everyone assumes is better.

Not a clamp

I took him to the hybrid operating room, balloon occluding to stabilize his blood pressure, embolizing the normal internal iliac artery and extending the stent graft into the external iliac artery.

Completion -there is an Amplatzer plug in the right internal iliac artery

This patient stabilized and had abdominal tightness due to his large hematoma which did not need evacuation. After a stay lengthened by concern for abdominal compartment syndrome, moderate pain, fevers, and bilirubinemia (due to the hematoma), he was discharged and never showed up for followup. None of the phone numbers work. Without followup, EVAR is a menace. We will keep trying.

Regrets, I’ve Had a Few…

The great feature of EVAR is that the complications up-front at the time of surgery are wonderfully low. This patient pictured above here presented in middle age with a rupture into the retroperitoneum. He was unconscious and had hemorrhagic shock.

The decision to perform EVAR was made late in the transfer because I did not have the images from the transferring hospital (another subject for another blog post) so I set up for both open repair and EVAR. En route to the OR, I scanned, slowly, through the CT images sent via CD-ROM, and my internal discussion went something like this.

“He’s a 50-something smoker in shock with a contained rupture of a 8cm infrarenal AAA with a good neck. Let’s take care of this in 30 minutes with a percutaneous endovascular aneurysm repair (p-EVAR).”

“He’s a 50-something smoker in shock with a contained rupture with a good neck -let’s take care of this in 90 minutes with a tube graft, open aortic repair (OAR).”

“With p-EVAR, he’s going to have just two groin punctures and much lower complication rate, shorter length of stay, similar to lower mortality. Look -his blood pressure is 75mmHg systolic!“

“That hypotension is permissive to minimize bleeding. With OAR, he’ll avoid abdominal hypertension and complications of a giant hematoma. Because he’s young, he’ll avoid lifelong surveillance. If anyone can clamp this AAA, it’s me...”

“Pride cometh before the fall. Get this man off the table and figure out the logistics later. p-EVAR. You open him up, he’ll exsanguinate and expire before you get the clamp on.“

I sighed, looked up at the gathered team, and announced, “p-EVAR.” The percutaneous EVAR is something I’ve been doing since 2004, long before it was a big deal, and we were done under an hour. His blood pressure stabilized, but general surgery was consulted for his abdominal compartment syndrome. With sedation, fluids and time, his urine out put recovered but his belly remained distended and his bladder pressures which were never seriously elevated, trended down.

It was made known to me that the patient had very limited insurance making followup surveillance challenging. Due to his coverage, he had to have his imaging done at designated hospitals, so I wrote a detailed note -basically the timings of his followup CT scan, and asked that the reports should be sent to me. I ordered a CTA prior to discharge which showed a type II endoleak adjacent to the graft and connected to both lumbar and inferior mesenteric arteries (first image above). After some thinking, I took the patient for an aortogram, accessed the IMA via the SMA and coiled into his AAA sac and the IMA.

It was only a few weeks ago one of my colleagues across town contacted me that the patient had been admitted with abdominal pain, a CT showing a type II endoleak from his lumbars, but a smaller AAA sac than his pre-repair size of 8.5cm. The patient is seeking to repatriate, and I doubt he would be able to get adequate followup in his home country without paying in cash. Happy that the patient survived his rupture, I still have persistent regrets at not getting him through an open repair, which I am sure he would have done fine with… Or maybe not.

Je Ne Regret Rien…

Recently I admitted a patient, in his 70’s, with a symptomatic 6.5cm infrarenal AAA with bilateral common iliac artery aneurysms, the right being 25mm, the left over 30mm. Because of the pandemic, he was stuck here, seeking to repatriate. Over ten years before, he had a segment of descending thoracic aorta repaired for a traumatic tear -probably one of the last before the wide adoption of thoracic stent grafts which work great by the way.

Cardiac risk evaluation revealed an ejection fraction of 35% with reversible ischemia on nuclear stress test. CTA of the coronaries revealed triple vessel coronary artery disease corroborated by catheterization. Off-pump CABG was planned which would eliminate the effects of cardiopulmonary bypass.

Preparations were made for EVAR with IBE of the left iliac aneurysm as a contingency, but there was no question that if the patient recovered well from his CABG, he would undergo open repair. This was because bell-bottoming or IBE must have regular coordinated surveillance which was not going to be easy with the patient leaving for another country in the middle of a pandemic. It is difficult to get followup to happen in normal circumstances (see above cases). I expressed my opinion to the patient and family and we agreed to see how the patient responded to off-pump CABG.

He underwent off-pump CABG with three vessels revascularized. He was extubated POD#1 and mobilized. By POD #4, he was on a regular patient floor, being co-managed by hospital medicine who takes care of all of our patients. The patient expressed readiness for the next operation. His kidney function remained normal. He was transfused 2 units of PRBC to bring his hematocrit to 30%. He was taken off Plavix, but kept on aspirin. On POD#6, he was taken back to the operating room for open aortic bypass. This would not have been possible without close coordination of cardiology, cardiac surgery, and vascular surgery. Choosing off-pump CABG was a critical element in being able to proceed with open aortic surgery.

Right branch taken to iliac bifurcation, separate bypasses sent to left internal and external iliac bypasses.

I do several things to decrease the physiologic impact of the operation. First is keeping all the viscera retracted under the skin. This simple move has the effect of decreasing the rate of intestinal paralysis and amount of fluid shifts that occur postop, akin to going retroperitoneal. This decreases the space you potentially have if you use standard clamps, but I use the Cherry Supraceliac clamp (image), DeBakey Sidewinder (transverse), or just a Satinsky clamp oriented transversely. This minimizes the occupation of volume over the anastomosis which always happens with standard aortic cross clamps. The anastomosis is easier without the clamp taking up valuable space.

Cherry Supraceliac Aortic Clamp

The iliacs are always clamped with Wylie Hypogastric clamps, again, with the principle of eliminating clamp overhang. Suturing is done with 4-0 Prolene on SH needles -this is plenty (link). The proximal anastomosis wants to bleed, and sewing to a fully cut ring of aorta ensures good posterior bites but also allows for sliding a band of graft down over the anastomosis (Dan Clair calls this a gusset) which works well at creating a hemostatic proximal anastomosis rapidly-trust me, getting this done well is the key step of the operation. Before closing, I infiltrate the rectus sheath and preperitoneum bilaterally with local anesthesia -lidocaine 1% with epinephrine 1:1 with bupivicaine 0.5%. The skin is closed with absorbable dermal sutures because staples create as many problems as they solve. The patient had cell salvage through the case and no extra units of transfused blood.

The patient was extubated that night and started on clear liquid diet. The next day his lines were removed and he was moved to the floor and started on regular diet when he expressed hunger. On POD#2, he was pacing floor, asking when he could be discharged.

Sternotomy and Laparotomy POD#2, walking the floor

As he was eating, walking, talking, breathing, evacuating bowel and urine, and pain free (well controlled), I saw no reason to keep him beyond POD #3 AAA/#9 CABG. I have kept in touch with him and his family and he is doing well and has given permission for this posting.

Satisfaction

This final case has confirmed several of my beliefs. First, calling something high risk can drive one to make bad choices and in fact endanger patients. This last patient would qualify as high risk on any international criteria, and you would not be wrong in quoting upwards of 30% major morbidity and mortality for cardiac revascularization and AAA repair, but you would also be tying your hands from offering the best solution for this man who fortunately was able to undergo two prodigious operations. He will not require much in the way of followup. Coronary revascularization with arterial conduit and open aortic grafting frees him from the need for close followup and reassures us that his repair is durable.

Second, calling something advanced and minimally invasive gives one cachet in the marketplace but forgoes careful discussion and consideration of what is being abandoned. The first two patients survived their ruptures but now face the consequences of having stent grafts. It is a shame when podium speakers at international symposia declare surgery to represent failure because this affects training by encouraging abandonment of hard to acquire skills. It seeps into patient perceptions and expectations. I hope that a balanced approach prevails. You have to be capable of both open and endovascular approaches to be able to offer the best treatment for a particular patient.

Finally, these old operations are cost efficient and there is a lot of room to improve these procedures with new perspectives, techniques, and data. I don’t operate the same way I trained, and it is only through continued application of operations that improvements can come about. As budgets tighten and economies are stressed, cost efficacy will rein in much of the interest and demand in new stuff unless it adds value. That said, I am grateful to our stent graft representatives who have worked to get us bell bottoms and IBE’s for when they will be needed. These grafts will be used when the time is right.

Categories
iliocaval venous ivc ivc filter techniques ultrasound Venous venous intervention vte

Leave Nothing Behind -IVC filter edition

Why There is a Literature on Filter Removal

A long time ago, there was the IVC clip which survives today as a vestigial CPT code. Then in the 1980’s, the Greenfield filter was introduced and changed the management of thromboembolism (reference). The explosive adoption of endovascular technology in the late nineties and early 2000’s drove the growth in implantation of newer generations of IVC filters that were designed to be retrievable. The people requesting the filters -the physicians, surgeons, and even patients looking to stop taking anticoagulation, were basing their decision on common sense –“sometimes, people are vulnerable to pulmonary embolism and are at risk of hemorrhage with anticoagulation, so an IVC filter makes sense.” There was frankly a data gap -a breach into which multiple companies jumped in with their own flavor of filter. Many interventionists saw no need to be selective -these were easy to place, and easy to remove, and if they stayed in there was the excellent long term results of the Greenfield filter to cite, and their referring docs asked for it. There was also the high revenue density (revenue/time) that gave filters a gravitational pull. There were several problems with this endo-enthusiasm (like in so many other cases). In the absence of data and with the aggressive marketing, too many filters went in for weak indications. We now know that most of these filters do not behave like the Greenfield, which itself is not completely innocent. Unless followup is part of a process, many patients neglected to have their filters removed. And finally, the data caught up and failed several filters which are no longer on the market and the indication for these filters is now quite narrow.

In 2009, I was asked to consult on a young man who was hospitalized for upper GI bleeding. The EGD revealed the tines of an IVC filter poking through (the jpg is somewhere I swear). The prior year, he had been in a bad car accident and had a filter placed but never had it removed. The filter had migrated out of the IVC into the duodenum and into the spine and aorta. I removed it operatively, and that was the beginning of a series of cases, about 1-2 annually in my general vascular practice, of filters that had eroded through the IVC and was causing symptoms of bleeding or pain. The pain typically was associated with a tine touching on or eroding into the spine. Biomechanically, the IVC is a collapsible tube and all the viscera on top of it weighs about as much as an equivalent sack of uncooked chitterlings when recumbent and grinds on the filter and any sharp parts. Imagine unbending a paperclip (figure) and putting it in the belly. Over time, that clip will poke a hole in something. Why would we not expect an IVC filter to behave otherwise?

An Iliocaval Thrombosis Below a TrapEase Filter

The patient is a younger man who over a decade ago had a TrapEase permanent IVC filter placed when he had a pulmonary embolism while having multiorgan failure. He was on coumadin briefly, but in the 17 years since filter placement, never had another venous thromboembolic event, but did develop venous insufficiency and varicose veins that were successfully treated. Several days prior to admission, he had been working out and developed back pain. After trying to sleep it off, he woke with severely swollen and painful legs. On admission, he was found to have no lower extremity DVTs, but had slow flow suggesting central occlusion. An abdominal x-ray showed the TrapEase filter (image below).

CT scanning and MRV showed the occlusion of the patient’s iliac veins and erosion of the struts of the filter outside the IVC (axial images below).  

On heparin infusion and bedrest, his swelling improved and we had a chance to go over our treatment options. They included

  1. Catheter directed thrombolysis
  2. Angiojet thrombectomy
  3. Large sheath thrombectomy (link)

–with one of the following–

  1. Surgical resection of filter
  2. Endovascular retrieval of filter
  3. Balloon venoplasty and stent exclusion of the filter (link)

Catheter directed thrombolysis of such a large volume of clot in the absence of a good flow channel usually necessitates multiple days of thrombolysis with return for venography and adjustment, with a small but not zero chance of fatal or disabling hemorrhage. It is expensive -multiple ICU days, return trips to the OR angiosuite. Angiojet thrombectomy is useful for clearing smaller vessels and grafts but due to the pulsing of the jet, it has a good chance at creating pulmonary emboli if the filter’s occlusion is not complete. Plus it is expensive and limited by the volume of fluid necessary to create the suction. Large sheath thrombectomy has worked for me in the past (link), but I worry about leaving behind thrombus that would embolize when the filter is removed or pushed aside.

Endovascular removal of the filter is always an option -I have removed a Greenfield filter over two decades in. I have never been able to remove an OptEase or TrapEase filter -there is nothing easy about these. I have a picture somewhere sent to me by a trainee who was consulted on a patient whose IVC was transected during the attempt to remove one of these endovascularly. That said, both my partners Houssam Younes here in Cleveland Clinic Abu Dhabi and Christopher Smolock at Cleveland Clinic Main Campus suggested trying with a two-team approach with a 16F sheath and wire from above and a 12F sheath and wire from below. That would be contingent on being able to clear the thrombus adequately.

Surgery to remove the filter is something I am comfortable with. It sometimes is the only option (link). Several times a year, I scrub in with urologists and oncologic surgeons to remove tumor from the retroperitoneum or IVC and the exposure is straightforward. When I only need control of the IVC, I make a transverse incision slightly above the umbilicus and mobilize the retroperitoneum leaving the kidney down to expose the IVC. For the IVC and iliacs, a midline laparotomy with a Cattell maneuver allows for broad control. Surgical thrombectomy would be great if the thrombus was all fresh, but challenging if there were differing amounts of fresh and chronic occlusion. The CT scan, showing the iliac veins and IVC to be swole with clot, suggesting most of it was fresh. Neither CT nor MRV could tell me if the IVC below the renal confluence was occluded. I had to be certain.

I went over these issues in detail with the patient and we agreed to proceed with diagnostic venography to check out the clot. The verbiage of clot, tofu, and cheese (link) worked well in communicating the information needed to achieve our goal of getting the filter out and the IVC and iliac veins cleared of thrombus. I sent a hypercoagulability study (even on heparin, the genetic component is useful information) which returned negative.

The diagnostic venogram is much more than just the pictures. For me, so much information is transmitted from the tip of a Glidewire as it passes through an obstruction or clot. Venography (image below) showed the thrombus but more importantly, the wire passed effortlessly in either side, got caught up in the bottom of the filter, but I was able to get through and the 5cm of IVC below the renal confluence turned out to be patent. The wire looped easily on both sides to the full extant of the dilated vein suggesting no chronic component.

I recommended surgery in our hybrid angiography suite. It would avoid multiple days of thrombolysis and its attendant risks. It would avoid subtotal clearance of thrombus. It would avoid failed filter retrieval and bailing out by stenting the filter (link), something acceptable in an older higher risk patient but not in an active young man. It would avoid surgery after several days of failed thrombolysis. The ability to perform venography and sonography with a clamp on the IVC ensured the ability to fully clear clot. And we had cell saver. After laying out my thoughts and concerns, the patient agreed.

The patient was opened via a generous midline laparotomy. I recruited the assistance of my friend Waleed Hassen, master urologic surgeon here at CCAD, in exposing the IVC. The vessel loop in the picture (below) is around the ureter. Green arrows on the right image show the anterior struts (there are three posterior struts). I had just assisted Waleed recently in removing a metastatic testicular tumor off the IVC, aorta, and mesenteric arteries through the same exposure.

The surprising finding was the anterior hooks of the TrapEase filter had penetrated the serosa of the overlying duodenum. While not perforating, it eventually would have, as the struts had eroded through the wall of the IVC and were outside the adventitial. After heparinizing the patient, the cava was clamped above the filter and I opened the cava lontitudinally along the anterior most strut. I got the sternal wirecutters and removed the anterior three struts along with their hooks. There were large draining lumbar veins which were acting as collaterals that were ligated. The filter was removed internally in pieces leaving the posterior three struts behind as they were outside the IVC lumen. The lower cone can be seen with tissue ingrowth and chronic thrombus. It was dangerous and bloody behind the IVC and I chose to leave these struts behind as they would no longer be pressing into the spine with the filter mostly out. (image below).

The initial thrombectomy was done manually by massaging the vein from either side and up the cava -the thrombus (image below) in the basin on the left expelled as a unit with a spout of blood. Thrombectomy with a #5 Fogarty proved ineffective in the large vessel, and I resorted to using a Foley catheter, directing it left and right, with removal of some more thrombus.

Duplex demonstrated clearance of thrombus from the right iliac vein but adherent thrombus on the left. I placed an 18F sheath into the left femoral vein over a wire I had directed up and over into the right iliac system and advanced the sheath while suctioning -this collapsed the vein and allowed the sheath to scrape the walls of the vein, retrieving the final clot material in the right basin. Duplex confirmed the absence of clot in the left iliac vein. The venotomy was then closed primarily and a completion venogram was performed (below).

The patient recovered and was sent home after a duplex confirmed patency of his leg and iliac veins and IVC. He will be on 3 months of a NOAC for provoked DVT.

Discussion:

Most of these filters can be retrieved with endovascular techniques. The principle is of gaining control of the top of the cone and collapsing it like an umbrella. For the Cordis TrapEase and OptEase filters, both cones have to be collapsed, and the struts which will have grown into the walls of the IVC have to be be stripped away from the IVC. I had attempted removal of an OptEase with control from above when I was in Ohio, but like in this case, the filter had tissue ingrowth on the lower cone making looping and control of the filter difficult as the hook was encased. While I was able to collapse the filter into a 16F sheath supported through an 18F sheath, it was clear the IVC was invaginating into the sheath and with enough force, I would tear the IVC. It is not the worst thing, perforating the IVC, as it is a low pressure system, and a small perforation is tolerated, but a large one needs operative repair. This can be avoided with surgical removal of the filter.

Performing this in the hybrid suite allowed for complete clearance of thrombus. That said, the thrombus in the internal iliac veins likely did not come out, nor did I seek to clear them. Rather, I will rely on systemic anticoagulation to do this for me.

I use duplex sonography intraoperatively liberally during my procedures. During EVAR, transabdominal ultrasound is sufficient in ruling out or specifying endoleaks. During complex kidney transplantation which I sometimes participate in, duplex is a critical tool for evaluating flow. In this case, images showing a cleared vein (will post, currently stuck in portable ultrasound memory) assured me that I could open the clamps with confidence that pulmonary embolism could be avoided. Gratifyingly, the patient had immediate reduction of leg swelling and can be expected to avoid problems as nothing (such as stents) was left behind in the vena cava lumen.

References

  1. J-P Galanaud, J-P Laroche, M Righini. J Thromb Haemost 2013;11(3):402-11. doi: 10.1111/jth.12127.
Categories
bypass CTA EVAR open aneurysm surgery taaa tbad techniques TEVAR thoracabdominal aortic aneurysm type b aortic dissection

Debranch First! or Why Haven’t We Done This All Along for Thoracoabdominal Aortic Aneurysms?

figure 1

Context

Despite all the advances in endovascular repair of thoracoabdominal aortic aneurysms, no data shows their superiority in the mid to long term compared to open repair. That is why branched stent graft programs occur hand-in-hand with robust open surgical programs, to offer durable open solutions to younger healthier patients while mitigating risk in older sicker patients by going with a branched or fenestrated device. Despite these advances, clamp time and visceral ischemia persists as a challenge to safe performance of open thoracoabdominal aortic surgery. Even a straightforward group IV requires the surgeon to be swift. Time on an thoracic aortic clamp results in visceral ischemia with a predictable response of coagulopathy, acidosis, systemic inflammation, and renal insufficiency. Adding cardiopulmonary bypass mitigates some things (distal ischemia, normothermia, hypertension) but brings on other complexities (cannulation, circuitry, coagulopathy). Sewing to a Carrel patch allows one to perform one large anastomosis rather than four individual ones, gaining speed and time, but compromises by leaving aneurysmal tissue which could progress to a troublesome patch aneurysm. TAAA is a condition that demands referral to high volume centers. It is in high volume centers that these apex predator surgical conditions can be subdued. It is in these centers that branched/fenestrated stent graft programs can offer treatment for patients high risk for open repair. It is in these centers that patients can avoid compromises such as snorkels and chimneys. Unfortunately, these centers are long air flights away and the means of the patients may not match the desires. Out here in Abu Dhabi, half a world away from Cleveland, Rochester, Houston, Boston, Chapel Hill, New York, and Seattle, and over six hours from major centers in Europe, we usually have to find our own way. Thankfully, we have the resources in experienced staff and abundant materiel.

During my time at the main campus of Cleveland Clinic, I came to appreciate the hospital as a highly evolved tool for healing, but for open repair of TAAA, it still falls on the operating surgeon and the choices made that shaped the outcome. In this most invasive of operations, simplicity and efficiency translating to speed offers the only consistent path to success. My partner, Dr. Houssam Younes, who trained in Houston, mentioned that Dr. Joseph Coselli, has clamp times approaching 30 minutes for group II TAAA -an almost inhuman speed achieved by doing these cases every day. For this reason, stent grafts are popular because repair of aortic aneurysms can be achieved by more practitioners in widely distributed settings. Because of the marketing of all things minimally being better, patients come asking for endovascular.

Case

The patient is a fifty-something smoker who had a prior type B aortic dissection nearly a decade past who presented with substernal chest pain radiating to the back. He was found on CTA (figure below) to have a 6.5cm extant V TAAA starting above the diaphragm and ending at the level of the renal arteries.

figure 1

Closer inspection revealed it to be aneurysmal degeneration of the aorta at a large false lumen fenestration. The aneurysm had grown eccentrically into the patient’s right chest and retroperitoneum. The remaining dissection above to the left subclavian artery and to the aortic bifurcation was chronic and thrombosed. His pain waxed and waned with hypertension which initially had to be controlled with parenteral agents. His cardiac workup revealed normal ejection fraction and valve function, and no critical coronary artery disease on coronary CTA. Pulmonary consultation deemed him a low pulmonary risk for major surgery. I offered him open repair, and initially the patient balked, asking for an endovascular repair, but I carefully walked him through the concepts, principles, and data guiding my recommendation. Yes, in a rupture, I have stented and followed with visceral debranching (link) and we have placed multiple snorkels in a very high risk octogenarian with a rupture, but who would offer endovascular repair to an otherwise good risk 50 year old?

The operation was initially planned in the standard way with cell salvage, plan for clamping in the transition point where the descending thoracic aorta took a rightward turn. The sequence of operation was for proximal anastomosis, right renal anastomosis, cooling the left kidney, celiac axis (CA), superior mesenteric artery (SMA), left kidney, and finally distal anastomosis with reimplantation of any prominent intercostal vessels. Preop imaging suggested the one at the T12 level was large. CT surgery was asked to be available for cardiopulmonary bypass via left atrium and femoral vein. Cardiac anesthesia and I had a discussion about intraoperative monitoring and management. Plans were made for CSF drainage -despite recent papers suggesting as much harm as benefit from these drains, I still feel critical time is lost if the patient is ventilated for a prolonged period postop and motor evoked potential monitoring is not available. The culture of CCAD mirrors that of Cleveland Clinic’s main campus in Ohio, and collaboration is ingrained. It was also serendipitous that one of the clinical associates, Dr. Niranjan Hiremath, had a particular interest and training in aortic surgery and suggested something amazing.

The Game is Changed

Dr. Hiremath trained in both vascular surgery and cardiothoracic surgery in Melbourne under Dr. Matalanis. Drs. Matalanis and Ch’ng published a series of 5 patients done with a separate branched bypass to the visceral vessels fed from the cardiopulmonary bypass circuit (reference). A separate aortic bypass was then performed and this truncal visceral graft was anastomosed to the main aortic graft. It was a visceral branch application of what is commonly done for the aortic arch great vessels. It was clear to me that this concept eliminated the need for desperate speed, and minimized clamp time to the 5-15 minutes required for each visceral branch anastomosis. A game changer.

My process for incorporating new concepts to an operation requires comfort and familiarity. The familiarity with this modification had everything to do with my extensive use of shunts during peripheral bypass surgery. Placing the shunt into one of the renal branches of a 4 branch Coselli graft turns this graft into a live blood vessel. By fixing the proximal and distal ends of the graft in the correct orientation and position relative to the branches, each of the visceral branches could be anastomosed to the graft one at a time while the patient’s aorta remained unclamped. This is best described with the sketches I put together for the preop huddle (gif and figure below).

figure 2 animated

Figure 2

Even though I have done many of these operations, because of the smaller population at risk, thoracoabdominal aortic aneurysms are a relatively low frequency disease and no assumptions can be made. The fact was, it took very little convincing for me to understand this concept as a game changer, but I took the liberty of modifying it for the particular situation of the patient. Every operation is ultimately another quantum of experience for the people involved to take away priceless information for the next one which will always be unique. We must take these as opportunities for improvement. For once in a long time, I felt this would be a big improvement.

Day of Surgery

Our operations always start with a huddle, but this one was different because of the numbers of people involved. There were the cardiac anesthesiologists, some of the best I have ever worked with in my career led by Dr. Dominique Prudhomme. The cardiac surgeons, Dr. Tareq Aleneiti and Hiremath, who planted this idea, along with the perfusion team, cardiovascular nursing team, and my partner Dr. Younes walked through the steps of the operation with me, with bailout points and plans B and C (CPB with hypothermia and circulatory arrest as a last resort for any unforeseen uncontrollable bleeding). I felt like I was the ringleader in a heist movie, only in this case, rather than jewels, we were grabbing something actually priceless (figure 3).

figure 3

The patient was placed in the right lateral decubitus position across the table break in the golf backswing position with pelvis relatively flat to the shoulders which were upright. The incision extended from the top of the sixth rib into the abdomen. This dissection is really two -the thoracotomy and separation of the peritoneum from the retroperitoneum linked by the takedown of the diaphragm and cutting of the costal margin. It is a tactile portion of the operation -only the hands really understand when to pull down and separate the two layers. The celiac and SMA are entangled in myenteric plexus which had to be cut to exposure sewable lengths of both. The left renal artery was also tricky in that the prior inflammation of the dissection resulted in stickiness of the tissues. It goes quickly and we have this exposure (figure 4).

Figure 4

Heparinized

The patient is heparinized with a goal ACT around 250. Not enough for CPB, but good enough for rock and roll. The cardiac surgeons placed a cannula within a double ring of advential sutures, cinched with Rummel tourniquets and secured with an 0 silk tie -a maneuver I did many times myself during my cardiac rotations in residency. This was placed on a Y connector, one branch going to the CPB pump in case of a need to go to plan C, and the other to a tubing connector inserted into the right renal artery branch of the Coselli graft -a slight modification of the original plan (figure 5).

figure 5

The other branches were simply clamped and the aortic ends of the graft were rolled up with a straight Kelly and secondarily clamped with aortic clamps -this gave weight to the ends letting them be positioned in a way that kept the branches oriented properly. There is need for precision and prediction as everything rotates back 45-90 degrees and the viscera sit on the grafts and the anastomoses. That is why keeping some length is crucial -this length accommodates this rotation. The Coselli graft is opened to systemic pressure by releasing the shunt. The proximal and distal ends of the main graft are twisted and double clamped to position the graft branches in the correct radial and z-axis orientation.

The aortic and branch exposure with takedown of the diaphragm is a standard exposure. One technical difference for this procedure is the need to expose about 2cm of the CA and SMA. Typically, only enough to clamp the vessel is necessary in standard surgery as these vessels are prepared with aortic buttons or anastomosed as an island patch. These vessels are surrounded by myenteric nerve plexus which feels like fascia or scar tissue but can be divide. Use of a hook cautery typically used in laparoscopic surgery along with a Ligasure speeds dissection.

These arteries, starting with the left renal artery, are ligated at the origin and divided for end to end anastomoses to the Coselli graft branches. As these arteries are only briefly clamped for the anastomosis while the remainder are getting flow from the aorta or the shunted Coselli graft, visceral ischemia is minimized. I still chilled the kidneys with manual injections of cold Ringer’s Lactate via large syringes and Stoney injector tips. The final product is shown on figure 6.

figure 6

The operation no longer felt like a sprint. The atmosphere was lively and relaxed -something that does not happen in these cases even at closing as exhausted residents or fellows focus on stitching together all the separated layers of the patient’s chest and abdomen. I played a soundtrack of classic Bollywood tracks, alternating between mellow and lively.

What was striking was the absence of the need for blood transfusion -about a liter and half ended up in the cell saver, and the patient received 2 units of plasma, out of tradition. The patient had a minimal brief plasma lactate elevation which did not persist. He was closed with a chest tube and brought to the cardiac intensive care unit, stable, not on pressors. He was extubated that night, and moved all of his limbs to command. The chest tube was removed on POD#2, and he left the unit to recuperate on the floor. Amazingly, his serum creatinine did not rise significantly. Prior to clamping he received the usual cocktail of mannitol but it was likely unnecessary. Most of these patients, even with revascularizing first after the proximal aortic anastomosis in the fastest of hands, there is at least 30 minutes of ischemia manifest postoperatively as a rise in the creatinine with recovery in most. This rise was brief and transient (graph).

GRAPH

In the visceral circulation, the ischemia in the normal open repair is manifest postoperatively as systemic inflammation requiring pressors, persistent lactic acidosis, and coagulopathy, which at best is transient but at worst, fatal. This patient had no significant shift in any of these parameters. He had his CSF drain removed POD#2 after clamping for 24 hours, and was discharged home POD#11, having to recover from right chest atelectasis and a blood patch placed for persistent headache. CTA prior to discharge showed a good result. The left renal graft had been on stretch but was rendered redundant on repositioning of the viscera. No stenoses were noted.

figure 7

Aftermath

Of course we are writing this case up, but case reports by their form cannot be overly enthusiastic whereas on my personal blog I can be excited. The normal course of postoperative recovery, the ebb and flow taught in surgical critical care books, is a result of ischemia, blood loss and replacement, fluid resuscitation, and cardiopulmonary support. Add to that cardiopulmonary bypass and you get an additional hurdle for the patient to recover from. This technique of shunting reminds me most of the temporary axillofemoral bypass. When I was a fellow at Mayo, I assisted Audra Noel in taking an elderly patient with a 25% ejection fraction through open aortic surgery with nearly miraculous recovery largely by avoiding the factors that trigger the ebb and flow. This technique is easier but mandates a strong normal segment of thoracic aorta to serve as inflow, otherwise an axillary artery will need to be cannulated.

Spinal cord protection is made easier with this technique by avoiding the massive fluid shifts, the pressors, and the acidosis in a typical thoracoabdominal aortic aneurysm repair. The blood pressure and cardiac output were never seriously perturbed. Several large intercostals and lumbar arteries were encountered and they backbled so avidly, after the short operation that I really felt there was no need to revascularize them. The spinal drain was kept open only for a day, and kept another day clamped to ensure that it would not be needed before removing it.

If you accept that spinal cord ischemia is multifactorial, we had avoided those factors. The absence of massive blood loss, negligible pressor use, no fluid shifts, minimal ischemia, no significant acidosis, no prolonged OR and clamp times, no blood transfusions, and the presence of avid back bleeding suggesting strong collateralization, compelled me to end the operation without revascularizing these intercostal vessels.

The patient recuperated for an ten days after his operation but was walking from postoperative day #1. He had atelectasis due to mucus plugging in his right lung base and was treated for aspiration, but clinically did not have a pneumonia and his atelectasis cleared with chest physiotherapy and nebulizers and was discharged home. Gratefully, he has given us permission to discuss and study his case.

There is no success in these cases without a team, and we are blessed with talented caregivers. This technique greatly reduces the physiologic impact of this surgery on the patient, reducing the injury to the equivalent of a broad sword cut from chest to abdomen that missed all the vital organs and vessels. In the right hands, this concept will broaden the appeal of open repair of these challenging aneurysms.

Reference

Matalanis G, Ch’ng SL. Semin Thoracic Surg 31:8:708-12.