Enough Flow!

I got a call about a graft fistula that had a stenosis. “Where?” I asked. At the arterial anastomosis, the velocities were high -500cm/s. My next question was, “is there a problem with dialysis?” The response was, “no.” I reassured the caller and then asked what the velocities were in the mid graft. Around 200cm/s.

Which made me pull out a sheet of paper to do some math. I have to confess, after learning higher level math and fluid flow during college, I had to think about it. The question was, for a pipe that goes from 4mm to 7mm in diameter, what is the ratio of velocities in the smaller pipe compared to the larger section?

The diagram above shows the calculations. This makes a lot of assumptions about the fluid that aren’t necessarily true but I went to medical school, not grad school.

The algebra comes out to the calculation that the velocity in the 4mm segment will be 3 times faster than in the 7mm segment. Which is pretty close.

At the end of all this, it struck me that I needed no other more relevant information than the answer to, “is the dialysis going well?” The velocity numbers for the proximal anastomosis aren’t helpful except under the condition “yes, there is a problem with dialysis.”

There is only the Boolean, Dialysis Good, true or false. Enough flow? implies we know the exact number, a magic volume flow number. The problem with focusing on flow is that there is a problem with too much flow. Arteriovenous shunts are like adult ventriculoseptal shunts (VSD). They burden both sides of the heart. It’s like hitching a trailer on a car. Some cars like SUVs are fine for this, but imagine hitching a boat on a tiny car, which what happens to patients with bad hearts and renal failure.

We don’t have many good options in heart failure or severe systemic atherosclerosis than a catheter. Catheters are just awful, but in heart failure, any amount of flow may be detrimental.

I recently saw a patient with no fistula flow, but a patent and aneurysmal segment of cephalic vein fistula remained and inflated with expiration (above). The outside hospital had placed a tunneled catheter in the right internal jugular vein, but it failed to draw enough blood and they had taken to accessing the cephalic vein with a 14g needle and returning the dialyzed blood via the catheter. Here is a case of the nonflow access. The fistula has gone down at the anastomosis several months before -this is rare to have both a widely patent cephalic vein and a closed anastomosis.

The draw from the vein worked well because there was a siphon to the right atrium and on dialysis days, she was fluid overloaded enough to keep the remnant cephalic vein inflated.

The lack of arterial flow meant that return couldn’t happen in the same vein, but imagine if she had the same in the other arm or better, on the thigh.

Which then made me think that a dilated and varicose thigh vein with a patient sitting slightly upright would be fine for access. Why not? And accordingly, in heart failure patients, high venous pressures are the norm especially in the legs when the head is up. Can we make an access for heart failure patients that takes advantage of their fluid overload?

It would work like this. In both thighs, the valves in the saphenous vein are cut using a endoluminal valvulotome, particularly the anterior thigh tributary. Then you wait. The combination of heart failure and bipedalism will result in huge veins. Once the veins are huge, you could make a very small fistulous anastomosis, but I don’t think it would be necessary.

Some people will have large superficial veins that will allow for dialysis access even without a fistula. Crude drawing below if dilated veins created on the thigh.

Knee high stockings, of course.

Incidental Pheochromacytoma

An oldie but a goodie from my first blog, “The Pipes Are Calling” on Medscape. This case came to mind when I recently diagnosed a pheochromacytoma from my clinic -middle aged man with difficult to control hypertension and unilateral renal artery stenosis. One of the most critical lessons learned from medical school, the Columbia University College of Physicians and Surgeons, was to be a complete physician, to be curious and engaged in the well being of your patient even outside the narrow focus of your specialty. This I learned especially from people like Drs. Harold Neu and Mark Hardy.

Incidental Pheochromacytoma

W. Michael Park, MD, Surgery, Vascular, 05:24PM Jun 23, 2010

The patient is a middle aged man who developed rest pain of his left leg after CABG for 3VCAD/MI. Workup revealed an occluded left iliac arterial system with diffuse atherosclerosis of his aorta and iliac arteries. He had a long history of bilateral calf claudication and his right SFA was occluded and his left SFA was diffusely diseased. CTA was performed and showed the described anatomy

And a “2.2cm peripherally enhancing mass” probably representing a lymph node with central necrosis, adjacent to the aorta.

I proceeded with aorto-right iliac and left femoral bypass, planning on later leg revascularization as needed after establishing inflow. During the retroperitoneal dissection over the aorta, I ran into this purplish mass and on manipulation, the patient’s blood pressure shot to 210mmHg. As my brain processed, my resident who had just finished reading his chapter on endocrine, said, “this could be a pheochromocytoma.”

That tumor was out quicker than you could say “snit.” Frozen section, and later final pathology returned paraganglionoma.

The patient recovered well and graciously gave permission, as all my patients here do, to allow this to be discussed. He noted that hypertension kept him out of Vietnam. Records showed an uneventful CABG.

Applying the retrospectocsope, I will now be far more wary of midline retroperitoneal lesions that are highly vascularizad.

Innovating Our Way Out of Not Having Enough Vascular Surgeons

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View out of my balcony, sometimes you need many pieces to assemble a beautiful whole

Innovating Our Way Out of Not Having Enough Vascular Surgeons

This year’s SVS meeting featured a sobering assessment about the vascular manpower deficit affecting North America at the E. Stanley Crawford Critical Issues Forum, moderated by Dr. Michel Makaroun, MD, president-elect of the SVS. 35-45% of practicing vascular surgeons plan on retiring in the next decade by conservative estimates. We are not attracting enough candidates for the training programs. The solutions, including decreasing the length of training, public relations campaigns, and incentivizing retention have had mixed results, but we have yet to see a sustainable rise in vascular surgeon numbers.

Burnout driven by lack of work-life balance, the advent of electronic medical records optimized for billing, the passing of the private practice era, and the constant need to adapt to new techniques, create a persistent downdraft on staffing. So as some hospital face the reality of having to contract services, little attention is given to delivering best care with the staffing that we have. Changing how we practice is the only viable solution.

There are an estimated 3000 active vascular surgeons in the US. Imagine if all the cheese needs of this country could only be met by 3000 artisanal cheesemakers who make cheeses one at a time and want to live in places with international airports, BMW dealerships, and major league sports teams, and must have 3-4 partners to share cheese call. If you are a rural hospital in dire need of vascular surgery services and your one vascular surgeon is retiring, you are probably SOL.

When I was training, vascular surgery was oft touted as a primary care specialty. And that is how many of us still practice, managing risk factors, monitoring mild disease, as well as planning and performing interventions and operations. As much as I enjoy that kind of interaction, the half hour to an hour visit for a head to toe cardiovascular survey and discussion, educating patients and families about pipes and pumps, is incredibly inefficient. A healthcare system, a hospital, facing a staffing shortfall, has to do everything possible keep that vascular surgeon in the OR during work hours.

What is the core function of a vascular surgeon? Making good decisions and executing plans well. Decisions require data. What is this data? We laud the history and physical examination, but this is a throwback to another era. If you look at the diagnosis of myocardial infarction, it is not standard practice for a cardiologist to come and get a history, examine the patient, and declare that the patient is having a heart attack based solely on history and physical examination. It is a triage nurse in the ED who draws labs and orders an EKG which is read by a machine. These data points will tell you if heart muscle is being damaged. A process is started which triggers a team to come and take care of this patient. The hospitals focused on this actually drill their cath lab teams like pit crews. A stopwatch starts with the goal of revascularization under an hour.

Not so with peripheral vascular disease. The ischemic foot might have only a few hours depending on its presentation before it is irretrievably lost, but no matter -they sit in the ED until a vascular surgeon comes to speak to the patient and family, examine them, and then order tests, admission, consults, and operating room -typically all by themselves. Getting these patients into the operating room is in many places hampered by the lack of dedicated OR staffing, radiology techs, anesthesiologists, space, equipment, and critical care capacity. During work hours, there are scheduled cases that have to be delayed or canceled for another time, which takes time to do. After hours, the patient may have too many comorbidities to handle safely with the available staff. The vascular surgeon may have to bargain and cajole, to align several factions whose attention is demanded by many equally important concerns. If you decide to hold a lavish dinner party of twenty important guests -reserving space, calling caterers, inviting guests, arranging transportation – on short notice, you might pull it off once, but if you do this regularly, you are a masochist of the first order.

In the heart attack model, the history and physical examination is relegated to a series of yes/no or how long questions, and positive responses trigger a series of coordinated actions of a system -a reflex. In the leg attack model, there is no such system. I have to blame the vascular surgeons for preserving the current model.  Vascular surgeons are organized as a guild. Guilds are protective of their monopolies on skills and markets and fiercely resist change. Most vascular surgeons are terrified by loss of control, and cling to the notion of being misunderstood and unappreciated saviors. We can do better.

The area that needs streamlining is at the point of referral. The majority of time of a vascular surgeon is spent working up normal blood vessels, varicose and spider veins, leg edema and pain, and mild and moderate arterial atherosclerosis. This work initially does not require a vascular surgeon but rather a focused set of policies and initial diagnostic studies that can be administered or ordered by any caregiver. Reducing the need for vascular surgeons at this point in vascular care will go a long way in extending the vascular work force at hand.

 

Point of Care Blood Flow Evaluation

Finding and declaring blood vessels to be normal is challenging and too often time consuming. Streamlining this will go a long way in freeing vascular surgeons to take care of disease.

The average caregiver is an inconsistent pulse taker. The palpable pulses are not always easy to find. Asking over the phone or as policy for someone to examine pedal pulses -the posterior tibial artery and dorsalis pedis artery pulses, is challenging. A positive is just as likely to be true or false as a negative. No cardiologist would ask a similarly detailed and technical question about an MI. In fact, they can’t ask, “Is there a pulse in the LAD?” Cardiologists make do with tests easy to obtain and interpret with certainty -the plasma troponin level and the EKG. The EKG is read by an algorithm so established and so tested, that it should stand as an example of early machine intelligence taking over a human job -but I digress.

What is our EKG? It is not the ABI -the ankle brachial index, because it is terrible at identifying disease, and is difficult to obtain reliably without practice. The closest thing to an EKG we have in terms of simplicity and accuracy is the pulse volume recording, the PVR (figure below). A FloLab machine, the machine used to obtain PVRs, will basically run itself once the cuffs are correctly applied on the leg, and the tracings are very easy to interpret. Unlike an EKG, there are no electrodes whose locations you must memorize. If the closest vascular surgeon is an hour away by ambulance, the transfer of a patient with flat waveforms and ischemic foot does not require a consultation on site. The patient would go to the vascular surgeon with no time wasted and no kidneys injured by CTA’s that too often fail to travel with the patient. Unlike an EKG which can be performed by many caregivers, a PVR requires both the equipment and a vascular technologist. A vascular technologist is not available 24-7 in most hospitals, and FloLab machines purchased for vascular labs are not meant to be dragged around the hospital.

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So let’s think out of the box about another box in every triage nurse’s cell, every ER and ICU bed, and on every hospital nursing floor. These are pulse oximeters with a digital tracing, and bonus points, some come with strip printers! Placing a pulse oximeter probe on the second toe and comparing to an erstwhile normal wave signal such as on an index finger can provide qualitative information about normality and disease. Normal waveforms and abnormal ones can be easily discerned. A flat line is another obvious finding when in comparison, a finger or an ear on the same patient has normal signals.

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How much better would a vascular surgeon feel about a transfer call that has this information, “digital waveforms are flat in this patient with rest pain and a bruised toe.” How much better would a vascular surgeon feel about a call about a patient with “digital wave forms are normal in this patient with toe pain and a bruised toe. We got an x-ray and there was a fracture.” The communication can be quite detailed and refined. For example: “The patient had no pulses, we think. Digital wave forms were dampened but pulsatile in a patient with a bruised toe, we’ll send to vascular clinic in the morning.”

A study comparing pulse oximetry signals and ABI in type 2 Diabetes Mellitus found the following results (link).[i]

Method Sensitivity Specificity PPV NPV
Pulse oximetry 74.1% 95.7% 83.3% 92.7%
ABI 70.3% 87.1% 61.3% 91.0%

These data suggests pulse oximetry signal is equal to and somewhat better than ABI. Why is this important? Cost. This information is better than asking unsure people, “Is there a pulse?” A vascular technologist need not be on call 24/7. Extra FloLabs for ED, ICU, and floors need not be purchased. The pulse oximeter with waveform tracing is nearly ubiquitous wherever patient’s oxygenation needs to be assessed in most hospitals. While not perfect, it has great potential for serving as vascular surgery’s EKG machine for critical limb ischemia. Policies and algorithms can be built out in collaboration with Emergency Departments and nursing departments that can effectively determine if blood flow is normal or abnormal at point of care. Effective emergency responses to critical limb ischemia can be authored triggered by abnormal findings. Acute limb ischemia protocols based on time sensitive responses can be initiated. All of these can flow from referring entities being able to determine objectively normal or abnormal blood flow.

Clinic

The vascular clinic is a sorting process where patients are determined to be normal or have mild, moderate, or severe disease. The vast majority of the time spent in clinic can be spent in triage by trained nurses and testing by technologists. Clear pathways and guidelines can dictate the ordering of vascular laboratory tests obviating the need for vascular consultation at this stage. Patients with normal blood vessels and vascular function are sent back to their physicians with the normal report. Patients with mild disease and moderate disease are sent to a physician with specialization in cardiovascular medicine for management of risk factors and periodic surveillance. At any point in the process, a vascular surgeon can be called to provide guidance and direct patients to different tests and consultations. The patients needing operations, based on correct indications and imaging are sent to a focused clinic where the surgeon and interventional team can review films, determine the urgency of indications balanced against risk, and plan and schedule procedures. Currently, vascular surgeons do all of this by themselves, as well as make hospital rounds, perform procedures, and interpret vascular laboratory studies, seeing one patient at a time.

In introductory computer sciences courses, search algorithms are taught to be brute force if you look at one item at a time for the thing you want, and to be efficient if you have presorted those items because every time you look, you can exclude part of the data set, ever shrinking the pool in which you search, making the search shorter and faster

The shortfalls in vascular surgeon numbers have as much to do with this dependence on the star chef cooking up one meal at a time, rather than a team working off recipes, with the chef directing the flow and occasionally jumping by the fire to make the most difficult of dishes. The first restaurant can seat three parties. The latter, easily ten times the number. Everyone gets fed.

Only asking how many vascular surgeons you need misses the big picture because there are many equally important questions. How many vascular technologists do you need? An accredited laboratory provides the critical diagnostics upon which decisions are made, and the surgeon should oversee but not be directly involved in the initial screening. Nurses trained to triage and order vascular laboratory tests and even perform the simpler ones is the second need. Third, is the cardiovascular medicine physician who manages those patients discovered to have mild to moderate disease, and depending on symptoms, refers severely symptomatic moderate disease and severe disease to a scheduling clinic. The scheduling clinic is composed of both interventionalists and vascular surgeons who plan interventions and operations.

Surgeons must be in the operating room to be effective. A well thought out and organized system, with interlocking teams, and well disseminated basic knowledge and awareness of vascular diseases reduces the need for a vascular surgeon to be present all the time in many places and ultimately increases the effectiveness of the vascular surgeons that are available by keeping them in the operating room. The system needs to be set up by the surgeon to allow clinic to be a setting mostly for consenting the patient for an operation or a discussion of treatment options.

Finally, vascular surgeons must be aligned with all the resources of the hospital including the considerable numbers of interventional cardiologists and radiologists, neurologists, and nephrologists. There is no reason someone should wait a month to get on the OR list for an iliac angioplasty and stent if an equally skilled and privileged cardiologist or radiologist has an opening the next day. The surgeon’s special talent should be open surgery and hybrid surgery -that which mixes open surgery and intervention in optimal measures which is not possible from a purely percutaneous approach. The key is frequent and easy communication between specialities and trust built by being in one shared cardiovascular institute.

Execution

There is a critical need of good operators. The acuity of disease and their solutions demand the continued presence and availability of open surgery. The fact is, many solutions are optimal in a hybrid fashion and for peripheral vascular disease, these options can only be offered via a vascular surgeon trained in both open surgery and peripheral interventions, or in a combined effort of open surgeon and interventionalist. And many disease categories can only be managed by open surgery.

The reality is that silos, economics, and practice patterns prevent this kind of combined effort. Market forces have pushed the training of vascular surgeons forcefully into the interventional realm at the cost of open surgical training. Some of the geographic maldisdribution of vascular surgeons has to do with younger vascular surgeons flocking to established practices where there are senior surgeons more comfortable in opening a belly or chest (or both). The trap they and hospital systems fall into is then allowing these new recruits to become the interventional specialist of that group, relegating the aging open surgeon to a narrow role, and then finding that the hospital has a problem when that surgeon announces retirement at 60. Every year, millennia of surgical experience retires to beaches and golf courses. The hospital systems should recognize this brain drain as a crisis and create work arounds that keep these skills going. The other opportunity lost is close coordination with interventional cardiologists, radiologists, and nephrologists who in many cases compete with vascular surgeons for the same patients but treat the patients based on their training and skill sets to the exclusion of potentially better operations offered by surgeons. This disjointed care creates both suboptimal outcomes for patients and high costs for hospital systems.

Commerce should never dictate the fate of a patient. A particular point is where competencies and privileging overlap, and guidelines recommend intervention over surgery as in the case of a TASC A or B iliac artery lesion. A patient should not be kept waiting weeks for a spot on a busy surgeon’s OR schedule when an open interventional cardiologist or radiologist slot is available for a iliac stent the next day. It should be a matter of practice that these cases are discussed and distributed, optimally in a shared indication clinic or rounds. Patients bumped off of a surgeon’s elective schedules for emergencies who could be cared for by an interventional partner without an added delay should be given that option. This kind of change requires a commitment to continual reorganization and optimization into a vascular institute.

 

Conclusion

The perfect vascular surgeon is a unicorn -well skilled, and experienced in open vascular surgery, but also versatile, innovative, and skillful in wielding a wire. I can name just a handful of unicorns. An apt analogy from the book Moneyball is the signing of superstars in baseball on the free agent market. The upshot of that book is that you can arbitrage for the valued metrics through signing several utility players with an aptitude for one thing or another which in sum equals or exceeds that superstar and get the final result -wins, in the same proportions as overspending on a superstar. Rather than searching for that unicorn, it is more important to set up the right system. Screening, testing, and management of mild vascular disease by a nurses and cardiovascular medicine physicians, while directing operations and interventions to vascular surgeons, cardiologists, and interventional radiologists should be the next step in the evolution of vascular care systems. There will never be enough vascular surgeons in the current system. The critical and rare competency is open vascular surgical skill. A surgeon who performs only interventions is not an “advanced minimally invasive practitioner” but rather someone equally privileged as an interventional cardiologist or radiologist, and therefore easily replaceable by an interventional cardiologist or radiologist specializing in peripheral vascular disease. A surgeon skilled in open vascular surgery is becoming rarer every year, but they are still out there, looking at brochures of real estate in sunny places. A team consisting of a cardiovascular medicine physician, many vascular  technologists, nurses specializing in vascular diseases, several interventionalists, and a vascular surgeon skilled in open vascular surgery working as a single unit, is far more easy to assemble than finding and recruiting a herd of unicorns.

 

[i] Kumar MS et al. J Assoc Physicians India. 2016;64(8): 38-43.  https://www.ncbi.nlm.nih.gov/pubmed/27762107

A lot of people can put in a stent graft, unfortunately only a few can take them out.

 

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Drs. Roy Miler and Xiao Yi Teng performing anastomosis on open coversion of an aortic stent graft, now graduated and in practice. A significant part of their open aortic experience is in addressing failing stent grafts.

I recently had to remove a stent graft for infection and got to thinking about how the number of people who could comfortably and confidently manage that has thinned out in the world through the unintended consequence of the medical device market place. In every surgical specialty over the past twenty years, many open procedures were replaced with a minimally invasive option which generally involved adoption of new technology and large costs to the hospital. These newer procedures were touted as easier on the patient while being easier to perform for the average physician than the open procedure that they were replacing. That was the other selling point -that one could do several of these operations in the time it took one open procedure. In most cases, they were at best almost as good as the open procedure but at higher cost.

In the marketplace, minimally invasive always wins. In many specialties it became untenable to practice without marketing these “advanced minimally invasive” skills. Hence, the wide adoption of robotics in urology outside major academic centers -during those years of rapid adoption the surgeons would get flown to a course, work on an animal model, then for their first case a proctor would be flown out and voila -a minimally invasive specialist is born. The problem comes when learning these skills displaces the learning of traditional open surgical skills. In general surgery, it is not uncommon to hear of residents graduating without having ever having done an open cholecystectomy.  It is also the case that many vascular trainees graduate with but a few if any open aortic cases. What happens when minimally invasive options run out? Who will do my carotid endarterectomy or open AAA repair?

The first case is an elderly man with an enlarging AAA sac despite having had EVAR about seven years prior. No endoleak was demonstrated but the proximal seal was short on CT. Also, it was a first generation graft which is prone to “peek a boo” endoleaks from graft junctions and stent anchoring sutures. On that last point, I use the analogy of a patio umbrella -after seven seasons, they can leak where cloth is sewn to the metal struts. It is very hard to demonstrate leak of this kind on CTA or duplex ultrasound because they are small. The patient had his EVAR because he was considered high risk for open repair at the time of his operation -moderate COPD, mild cardiac dysfunction. His sac had enlarged to over 6cm in a short time, and therefore open conversion was undertaken. No clinical signs of infection were present. A retroperitoneal approach was undertaken. After clamps were positioned, the sac was opened.

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The picture does not show it, but a leak from the posterior proximal seal zone was seen with clamp off. The clamp was reapplied and the graft transected flush to the aortic neck. A bifurcated graft was sewn to this neck incorporating the main body stent graft and aortic neck in a generous running suture. The left iliac limb came out well and the new graft limb sewn to the iliac orifice, the right iliac limb was harder to clamp and therefore I clamped the stent graft and sewed the open graft to the stent graft.

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The patient recovered well and went home within the week. He was relieved at no longer needing annual CT scans.

Who needs annual CT scans? Patients with metastatic cancer in remission.

The second patient was an older man referred for enlarging AAA sac without visible endoleak. The aneurysm had grown over 7cm and was causing discomfort with bending forward. He too had been deemed high risk for open repair prior to his EVAR. If he had had an early generation Excluder graft, the possibility of ultrafiltration would be more likely and relining the graft would be reasonable (link). This was again a cloth and metal stent graft which can develop intermittent bleeding from graft to stent sutures, and I don’t think relining will help.

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The patient was taken for open repair (above), and on opening the AAA sac, bleeding could be seen coming from the flow divider. It stopped with pressure, but I replaced the graft in a limited fashion from the neck to the iliac limbs as in the first case. This patient did very well and was discharged home under a week.

The third patient was another fellow referred from outside who had an EVAR for a very short and angulated neck, and a secondary procedure with an aortic extension in an attempt to seal the leak had been done. This failed to seal the type Ia leak. This patient too was deemed too high risk for open surgery of what was basically a juxtarenal AAA with very tortuous anatomy.

The patient was taken for open repair, and the stent grafts slid out easily (below).

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A tube graft was sewn to the short aortic neck and distally anastomosed to the main body of the stent graft -with pledgets because of the thin PTFE graft material in this particular graft. This patient did well and went home within a week.

All three cases are patients who were deemed originally too high risk for open repair, who underwent EVAR, then underwent explantation of their failing stent graft. Only one involved a patient whose graft was placed off the IFU (short angled neck), but the rationale was that he was too high risk.

What is high risk? In non-ruptured, non-infected explantation of failing stent graft, the mortality is 3% (ref 2) from an earlier series from Cleveland Clinic.  With stent graft infection, the 30-day mortality of surgical management from a multi-institutional series was 11% (ref 3) when there was no rupture. From a Mayo Clinic series, stent graft resection for infection came with a 4% 30-day mortality (ref 4). These were nominally all high risk patients at the time of the original EVAR.

Real world risk is a range at the intersection of patient risk and the expertise of the operating room, critical care, and hospital floor teams. The constant factor is the surgeon.

Endografts for AAA disease (EVAR, endovascular aortic aneurysm repair), makes simple work of a traditionally complex operation, the open aortic aneurysm repair. The issue has been the cost and risks of long term followup as well as endograft failure and aneurysm rupture. The Instructions For Use on these devices recommend a preop, a followup 1 month, 6 month, and 12 month CTA (with contrast) and annual followup with CTA for life. These devices were meant to treat high risk patients but high risk patients with limited life spans do not benefit from EVAR (ref 1, EVAR-2 Trial). These have lead the NHS in the UK to propose that EVAR has no role in the elective repair of abdominal aortic aneurysms in their draft proposal for the NICE guidelines for management of AAA (link). While this is a critical discussion, it is a discussion that is coming at least ten years too late. A generation of surgeons have been brought up with endovascular repair, and to suddenly announce that they must become DeBakey’s, Wiley’s, Imperato’s, and Rutherford’s is wishful thinking at best or wilful rationing of services at worst.

In 2006, Guidant pacemakers were recalled because of a 1000 cases of possible capacitor failure out of 28,000 implants for a failure rate of 3.7% -there were 2 deaths for a fatality rate of 0.00007%. EVAR-1 Trial’s 8 year result (ref 5) reported 16 aneurysm related deaths out of 339 patients (1.3%) in the EVAR group compared to 3 aneurysm related deaths out of 333 patients (0.2%) in the OPEN group.

Academic medical centers, behemoths though they are, serve a critical function in that they are critical repositories of human capital. The elders of vascular surgery, that first and second generation of surgeons who trained and received  board certification, are still there and serving a vital role in preserving open aortic surgery. My generation -the ones who trained in both open and endovascular, are still here, but market forces have pushed many of my colleagues into becoming pure endovascularists. The younger generation recognizes this and last year, I sat in on an open surgical technique course at the ESVS meeting in Lyons organized by Dr. Fernando Gallardo and colleagues. It was fully attended and wonderfully proctored by master surgeons. This is of critical importance and not a trivial matter. As in the 2000’s when endovascular training was offered as a postgraduate fellowship in centers of excellence, there is no doubt in my mind that today, exovascular fellowships need to be considered and planned and that current training must reinvigorate and reincorporate their open surgical components.

References

  1. Lancet 2005;365:2187–92.
  2. J Vasc Surg. 2009 Mar;49(3):589-95.
  3. J Vasc Surg. 2016 Feb;63(2):332-40.
  4. J Vasc Surg. 2013 Aug;58(2):371-9.
  5. Lancet 2005;365:2179–86.

Top 12 Things to Get Your Favorite Surgeon in 2018

1. Microsoft Surface Book 2. It comes in two flavors, Large (13.5inch) and Supersize (15 inch).

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Surface Book 2 13.5 Inch

Like Apple and their Macbook Pros, Microsoft decided to price it out of the reach of most people. In my opinion, it is worth it because of the versatility of popping off the screen and using as a tablet. Reading a journal articles is unmatched at 13.5 inch size.

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The Surface Book 2 13.5 Inch Detached as a Giant Tablet

The other feature is the 12 plus hours of battery life for both sizes although results may vary. The keyboard part has a second large battery and an NVIDIA graphics processor which makes short order of Fortnite Battle Royale. The storage options come steeply priced, but there is an SD slot -with a half height MicroSD adapter (link)and some fiddling with DiskManagement (link), you can trick the computer to thinking the SD card slot is onboard hard drive, so you can add 200-400gB for dumping pictures, media, and Dropbox onto it.

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Sketched on Tablet Using Sketchbook

Low usage apps can also be installed onto this drive. The pen allows you create nice artwork -something that I have always needed for my blogging.  And it plays nice with Apple -you can run iTunes (yes it sucks), and link iCloud to your calendar, photos, iPhone, and Mac desktop. The sweetspot is the Core i5 with 256gB SSD in the 13.5 inch version for about $1400, but if you can swing it, the Core i7 with a 1tB SSD and 15 inch screen (with listed 17hr battery life) is the way to go, but be prepared for sticker shock

2. Samsung Galaxy Note 8/9 Smartphone. I know, I have been a lifelong Apple user, but I wearied of the closed nature of the Apple ecosystem. Get a Note 8 and you can add as much memory as you need via the MicroSD slot (remember to change settings on your apps to make use of this). The AMOLED screens are gorgeous, the pen (pens are back!) lets you scratch down patients MRNs during phone calls and sign PDFs. Google services are great for a lot of things. Add a folding bluetooth keyboard and you have an ultraportable solution to avoiding the giant corporate laptop. The imminent release of the 9 should give you pause, but given the incremental changes under the hood, buy if you find a deal on the 8. The battery life is sufficient for all day use, plays nice with iTunes music, and takes some of the greatest phone pictures I have ever taken (below).

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3. Bluetooth Keyboards -I know they are incredibly boring and utilitarian, but hear me out. There are two form factors that bear consideration. First, the folding keyboards that in combination with a large screen smartphone, give you 95% of the capabilities of a laptop, letting you travel with bare minimum of items. The EC Techology Folding Blue Tooth Keyboard (link) is smaller, and likely not suitable for people with giant paws, but for me, who used to write long form essays and papers on a Psion Series 5MX, this keyboard works well, particularly because it has the phone/tablet stand built into it.

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Samsung Galaxy Note 8 and EC Technology Folding Bluetooth Keyboard

For several months last year, TSA restricted travel to the US with anything bigger than a smartphone. My workaround then was digging up an old Palm Bluetooth keyboard, but the modern stuff is far better. The EC keyboard is sturdier, rechargeable, usable with multiple devices (the one above links to 3 devices). It isn’t backlit but you can find those that are.

The other kind of Bluetooth keyboard that I love are the ones that incorporate retro keys -there are several that have old typewriter keys and others that have the large IBM keys -these both share the clicky key mechanism that were lost when island type chiclet keyboards became the norm. While I love the Macbook, and tolerate the keys, for long typing, I need a real keyboard, and lately, I am willing to spend on mechanical keys.

Why do I like them? For focused writing, the chunky keys with a loud clickety clack sound is incredibly comforting -it sounds like intense work to spit out words on these keyboards. I recently purchased a Bastron Wireless Mechanical Keyboard (link) which looks and feels like an IBM Thinkpad keyboard circa 1995. It is backlit and has a groove for placing tablets and smartphones, although I use it as the center keyboard of my writing station between my laptop and a large second screen. It is backlit which is a plus. Most of you are familiar with the bluetooth keyboards that are like mechanical typewriter keyboards, but I think aside from the asthetics, they are generally very costly and I don’t feel compelled to get one. This Bastron Keyboard is a keeper at the 35 dollars on Amazon (a clearance price). Some people have a difficult time managing the wonky Bluetooth and therefore it gets a 3-ish rating. Just sit tight and follow the instructions and you will be fine. Mine came with a free Bluetooth mouse. I give it a 4 -taking off a point because it uses AA batteries.

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Bastron Wireless Mechanical Keyboard

4. Smartwatches. Sure, go ahead and get a fancy automatic watch, but be prepared to pay through the nose in maintenance and repair fees as when five to ten years out, you notice the watch not keeping time well.

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The watch is round, the way it should be…

The repair fees may actually come out to the same price as getting a new watch. The newer generation of smartwatches offer so many useful functions that they trump their general fugliness. The Apple Watch and the Samsung Gear 3 both hit the right pricepoint for not crying when the inevitable better and newer versions come out. My Gear 3 offers customizable faces and quick swapouts of bands to match my wardrobe. It tracks my activity and measures my heartbeat, and can record my runs. The battery is good for 3 days and recharges in about an hour wirelessly. Unlike the Apple watch, it is round.
5. A two week vacation in the middle of nowhere. All surgeons want out of a vacation is to be completely away from work and preferably with a stunning view. I suggest the following. A two week cruise with a private balcony and view of the ocean and never getting off the boat for excursions. A cabin/house rental off season -that means going to Vail or Aspen in the summer or Martha’s Vineyard or the Hamptons in the winter. Bring food for the apocalypse -Spam, pasta, rice, canned vegetables, oatmeal, powdered milk, sack of potatoes. The ultimate lonely vacation destinations are British microcolonies -the Falklands, the Hebrides, Prince Edward Island, Bermuda, Pitcairn. Unfortunately, they probably all have internet. Bring a couple bottles of whiskey and a box of cigars. Go shoot something with a local. Or spend two weeks on the transcontinental train across Russia from St. Petersburg to Vladivostok in a premier car.

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Go far away, eg. Maldives

6. Blank sheet journal of high quality. Moleskine makes a nice one, but when I travel, I always drop in on local stationers and arts stores for unusual blank books to write in. The Japanese in their infinite wisdom offer a cheap but high quality bound notebook of blank paper that you can find in Japanese bric-brac stores that are cheap but wonderful.

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From local Japanese Store (Daiso), for 10AED (about 3 dollars US), Personalized

I think that all surgeons need to keep notes on what makes their operations fail or work, and imagine what would make things better, but writing about your passions or scratching travel notes is great brain exercise. The bottom line is that an idea needs to be written down as much as a seed needs to be placed into soil.
7. Large capacity battery for recharging -I carry two of these Anker beasts (link). They will charge my Macbook and Surfacebook, and my smartphones multiple times. I can’t tell you how useful it is to not worry about low charges during travel. I bought mine 3 years ago and they are still going strong. They don’t need to be fancy, just incredibly reliable and able to recharge at the higher amperage required by tablets and computers. My MacBook will typically go from 25% to 100% on one of these power banks -nothing to sniff at when you want to write any where any time. Mine are 20100 mAh, but larger ones are available. They do get heavy and they must be on the carry on luggage.
8. Small bluetooth speaker. Not all operating rooms have good sound systems, but you don’t want to lug a huge speaker either. Most tablets will be sufficient for playing music at volume but without sufficient bass. You can play around with the acoustics by placing your smartphone or tablet in a large metal basin, but you want speakers if you want to hear the bottom half of your music, whether it be Vivaldi or Childish Gambino.

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Harman/Kardon makes a supercompact speaker that also is an excellent speakerphone and in a pinch will recharge your phone (link). It’s is plenty loud and gives a nice balanced sound. If you want more bass, you want something like the Bang and Olufson of bluetooth speakers. Again, there are larger speakers, but I’m focusing on ones that will fit nicely in a laptop bag, and I’m happy with my Harman Kardon’s.
9. Giant E-Ink Tablet. Imagine reading journal articles in original A4 size. While it is possible to do this with a standard tablet, the screen will cause eye fatigue. Printing this out means carrying heavy paper copies that are easily lost.

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Boox Max 2 In Monitor Mode. It’s also an Android 6.0 Tablet

You might remember that Amazon once had a Brobdingnagian Kindle -the Kindle DX, but has focused on ever smaller form factors. I had the DX and reading PDFs on it in normal size was a pleasure. Unfortunately, the DX was an early Kindle and not particularly fast nor high resolution. While it was excellent for its time, it has comparatively a muddy low resolution screen when compared to modern Kindles. So you would think in the effort to go paperless that modern hardware and software would combine with state of the art E-ink to create a great reader. Well, Sony put out the Sony DPT-RP1/B 13” Digital Paper, but based on feedback on Amazon, it is clear that Sony hasn’t shaken off their great handicap which is putting out great looking products with terrible names that fail in crucial fashion either in software or hardware. In this case, the proprietary software cuts the legs off this device. The Chinese on the other hand, have put out what appears to be an excellent 13-inch E-Ink tablet running Android (link), the Boox Max 2  and allowing for direct wired second monitor function. This is the sweet spot, but unfortunately is quite pricey. That said, if you really want to make your surgeon smile, this is the gadget. It has that modern high resolution E-ink screen that is close to paper linked to a touch screen and medium range Android hardware. The reviews say that it works well as a second monitor, but I would use it in combination with my bluetooth keyboard and IAWriter (link) to create a focused writing station.
10. Japanese massage chair. My father got one a couple of years back, and now whenever I visit him, I have to wake him up and shoo him out of this chair to get an intense deep tissue massage. The calf and forearm massage function is a must. When I get my forever house, a dark room with several large screens and this chair will be the core of this home. Put on golf or an animal documentary with Attenborough and you get the best nap of your life!

11. Audible.com Subscription. While commuting or long haul driving, catching up with the latest business managment book or historical non-fiction tome makes the 10 minute red lights in Abu Dhabi a pleasure. While there are free podcasts galore, audiobooks lets you get through the latest materials with minimal fuss. There are often free books with coupon codes from some podcasts. Suggested listening -Norse Mythology by Neil Gaiman, 1453: Holy War for Constantinople and the Clash of Islam and the West by Roger Crowley, How to American: An Immigrant’s Guide to Disappointing Your Parents by Jimmy O. Yang, and Ready Player One by Ernest Cline.

12. Ichiran Ramen Instant Noodles. If you haven’t been, you need to go to Ichiran Ramen in Brooklyn, NY. There you will be seated in a single booth, solo with a small cryptic order slip. You choose the texture of your ramen -basically under or over al dente, the add ons like fish cake, seasoned egg, pork belly, and some sides and ring a bell. The roll up shades peak and a hand, no face, reaches in and gets your order. You wait about 5 minutes, and the shade opens and your ramen is placed in front of you. One slurp and you are transported to a kind of ramen induced rapture. It is that good. The noodles are great -they invested a serious amount of time to create a noodle factory out in Brooklyn, but it is the soup that brings you to your knees. The donkotsu broth is made from pork shoulder and bones and has character, depth, and a lingering finish that burnishes itself into your memories. You can’t eat at a normal table and get the same effect -hence the flavor concentration booths. As you walk out, you can purchase boxes of packaged instant Ichiran Ramen which cost as much as buying one fresh, but lets you enjoy the noodles and broth at home or far away like here in Abu Dhabi. You can buy them on Amazon (link) but it looks to be overstock. 20180727_144208They opened a branch in Manhattan, but my kids say it wasn’t as good as in Brooklyn. I can’t imagine what it must be like at the original store in Japan, but I am planning an entire trip just to eat ramen.

Addendum

This post is meant to be a review of items and satirical in presentation. It is not a demand for gifts or services in kind. Anything sent from anonymous sources will not be acknowledged. Please consider donations to your local charity -in Cleveland, the United Way offers services to the needs of the community. Surgeons are perfectly fine getting these things for themselves.

The Interstitial

https://opmed.doximity.com/new-interest-in-the-interstitium-is-like-people-suddenly-obsessing-about-the-stuffing-in-sofas-308b1336a317

By Woosup Park, MD

A recently published paper caused breathless worldwide headlines about a “new” human organ hiding in plain site — the interstitium. It had me smiling because vascular surgeons, the good ones, recognize it and have been managing it for a long time. The interstitium is described as the space outside the cells. The new interest in it is like people suddenly obsessing about the stuffing in sofas. It is the body’s contained negative space and it is the most important organ because it was the first. It has been there all the while.

The genome and its expression, the organism, carry the past like hoarders. Look at a skin cell, and you see a nucleus and a cell membrane, the hallmark of the eukaryote, and the mitochondria that it took captive in eons past when it was a sea bacteria that was eaten and refused to be digested. The next most important step in evolution was multicellularity and specialization of these cells. The earliest efforts started as clumps of cells, but clumps have a limit — every cell had to have exposure to the outside and eventually these became spheres with a hollow internal space. Here was the first interstitium — the first inside, the first not-outside.

To these first animals, segregating an internal space different from the outer sea had advantages. You can concentrate nutrients inside when the seas outside are plentiful and use these when they are not. Add some structure and you have an endoskeleton — we share this with sponges inside this interstitium. As the organism became larger, this sphere flattened and some became animals with one pore ingesting and ejecting and others with two holes. We fall into a lineage that found transiting food through a cylinder to be advantageous. The nutrients were digested and absorbed from the worm into this internal space. The interstitial waters needed to be mixed as food came not from the outside but from this internal protodigestive tract, to have currents and streams. This was done with the development of tubes lined with smooth muscles that beat, interspaced with one way tricuspid valves. This primitive circulatory system is seen in many of our spiny sea cousins like starfish and sea cucumber, and lives in us as the lymphatics.

The interstitium is the remnants of this primitive sea creature that we carry with us, carrying within this pouch of internal sea. The fluid that fills blisters is a kind of briny sea water. When you see an edematous patient, observe the level of this sea by seeing where the edema ends. See how easy it is to milk out this edema out of a hand or foot, just as it is to squeeze the water out of a sponge. Edema is so common that it is easy to forget that so many diseases cause failure of the lymphatics — the bilge pumps of the body, and that on this tide may come many other things that makes the problem worse. In other instances, it may be just high tide in Venice, right before all the sewage gets washed out into the Adriatic.

The interstitium, as much as it was the progenitor of the circulatory system, is likely the foundational element of the nervous system. The various ion pumps are highly conserved and are useful only when concentration gradients are stable. The bioluminescent jellyfish is testament to this. Without the interstitium, cross membrane voltage potentials cannot be maintained. It is the bioelectric spark that life motion. If a planaria, a flatworm, is to have a soul, it resides in the interstitium. It is the spiritual ether bottled inside us. The ghost in our machine swims our portable primordial sea.

These old parts and compartments are hiding in plain site. The lymphatics beat and spread some of the nutrients from the gut into the venous system in connections up at the base of the neck. Both have been superseded by the portal venous system and the circulatory system but the lymphatics persist because there was no reason to abandon it, but possibly it is critical to our existence. The interstitium must play a critical role in homeostasis in the same way that the older autonomic nervous system plays critical subliminal roles by being both a buffer and a store. Every cell in our body is in contact with this inner sea as much as the first cell was afloat in the primordial one.

The interstitium is the final contact point between each cell and the organism as a whole. Oxygen does not go from alveoli to the skin without transiting the interstitium. Just as we are only beginning to grasp the complexity of genetics and the heredity of epigenetics, we are just noticing the interstitium. Up to now, it is as if we have been studying the outlines and histories of Byzantium, Rome, and Carthage, in isolation without studying the depth, composition, and currents of the Mediterranean.