This topic, as opposed to the thumb reconstruction, is tested very commonly. So I would urge you, if you can, stay awake and try to pay attention. I'll try to give you some of the things that have been asked over the years and highlight those things. So again, nothing to disclose related to this presentation. So you say, why do we want to talk about chronic ischemia of vascular insufficiency? It's not a very sexy topic. And just like the toothbrush and the toilet paper, you think this is the worst problem in the world taking care of these disasters. And I guess the answer is because if you see patients like this, you can actually do them a service and often help improve their chronic pain that they have from ischemia and get these amputation sites to potentially heal, or at least to give you an idea of how to think about this. So there's two kind of components to chronic ischemia, the first being vasospasm. And if you look at different surveys and different literature responses, about 10% to 15% of the people report sensitivity to the cold in their fingertips and the tips of their toes. About 20% of the population in the northern climates will describe digital blanching, white color to the tips of the fingers and the toes, as well as numbness in the digits. And the other component, aside from vasospasm, is occlusive disease or embolic disease. This can cause pain, numbness, contribute to decreased productivity, and interfere with the quality of life. And so when you think about upper ischemia of vascular disorders, these are certainly much less prevalent than what you'd see involving the brain, so stroke or lower extremity or heart that you'd see with MIs, cardiac ischemia. But they can cause substantial morbidity and decreased function, so important to understand and also important for test-taking purposes for this exam. So for chronic ischemia, as I said, I've broken it down to two processes, the vasospastic processes. The primary processes are Raynaud's disease. This is a question that's come up before. What's the difference in Raynaud's disease and Raynaud's phenomenon? The disease is a primary process. The phenomenon is secondary to another cause, such as collagen vascular disease or another disorder. And then occlusive disease actually can create distal vasospasm, so it can be lumped into as a secondary cause of vasospasm. And then occlusive disease to occur primarily is typically related to either embolism, thrombosis, or aneurysmal disease. And so the key questions to ask for both of these conditions are what's the collateral circulation like and what's the sympathetic tone like? And if you can answer those questions, you can determine the best treatment for these conditions. So there's two components to the circulation in the hand, the macrocirculation and the microcirculation. The macrocirculation is really what everybody thinks about most of the time. And so the question you ask, is the vascular system competent? And by that, I mean the ability to regulate blood flow to fulfill the metabolic requirements and maintain cellular viability. And it's dependent upon the anatomy, the collateral circulation, the vasomotor tone, as well as the metabolic demands of the tissues. And when it's not able to meet these demands, you have vascular incompetence, which can result in pain, cold intolerance and numbness, potentially tissue loss or ulceration and then tissue loss. If you look at the microcirculation, this is the total blood flow. And it has two components, the nutritional blood flow, which is that distal most 10% to 15% typically, that provides the cellular and metabolic needs for the tissue. And then the thermoregulatory blood flow. And these are the AV shunts or the AV anastomosis. They're used to provide temperature control and help maintain blood pressure. And so if you look at the vascular anatomy of the hand, everybody knows and thinks about the radial and ulnar digital vessels. But what's often overlooked and not really thought about are these distal connections or the AV anastomosis there. And so here's a picture depicted from Green's operative hand surgery, Andy Komen's chapter. And you can see the nutritional capillaries out here distally. And so there's these connections between. And so your body can sense what's going on from a temperature standpoint. It'll figure out when it needs to shunt blood through these versus allowing the blood to go distally. And so as I said, vascular insufficiency exists when the nutritional blood flow or that distal most aspect is inadequate to maintain the cellular viability. So on physical exam, the things that you want to think about are capillary refill, the presence or absence of ulcerations in the tips of the fingers, and the peripheral pulses, both proximally, radial and ulnar artery, and the brachial artery, as well as distally out in the digits. And then you can use an Allen's test that everybody's familiar with in the distal form, compressing the radial and ulnar artery. But you can also do this in the digit. And then a handheld Doppler is really essential for this. This is just an example of one of them that we have. And so any Doppler is fine. But you really need that to be able to evaluate these patients. The diagnostic tests that you're going to get after your exam, the goal of these is to determine the anatomy of the vasculature system and the capability of the system to respond to stress. And cold tends to be a good stress. As we talked about, patients often have sensitivity to cold. So you can test them both before and after a cold stress to see their response to that. The two tests that are commonly obtained and commonly tested, segmental arterial pressures, or DBI, digital brachial indices. And in calcified vessels or in-stage renal disease, these tend to be not as accurate, but very helpful from a standpoint of vasospastic disease. And then digital plasmography, or PVRs, which helps quantify blood flow by measuring volumes. And so both of these are very helpful for vasospastic processes. So with a PVR, you're going to get a waveform back. This will help differentiate between occlusive or vasospastic processes. And then, as I said, you get it before and after a cold stress. So they'll do the exam, give you the recording, and then they'll repeat the exam after cooling the hand, either in ice or in a cold refrigerator type of hand place. And that'll help determine how it responds to stress or to cold. The segmental arterial pressures, or the DBIs, are obtained by obtaining occlusive cuffs. So essentially, a blood pressure cuff. And they have smaller cuffs for the digits. So they can compare the proximal areas, either at the brachial artery or the radial or ulnar artery, down into the fingers. And you'll end up with a ratio, which is very important as far as determining the adequacy of the blood flow. So this is an example of what this looks like for the lab. And they can measure this at multiple points. So brachial artery is going to be the key. And they can measure it all the way down to the fingers to help understand that. And so the key for treating this, as well as test taking purposes, is this number 0.7. So a normal DBI should be about 0.9 or 0.9. If it's greater than 0.7, there's adequate arterial inflow. And that's going to change your whole reconstructive options. If it's less than 0.7, it's inadequate arterial inflow. And so that supports the need for intervention of some sort. So this is a number that comes up often on test exams. So remember that 0.7. So this is an example of what it looks like with both the waveforms, as well as the pressure measurements in the fingers. And so you can calculate the numbers. For occlusive disease, I still think arteriogram is the gold standard and the best way to evaluate these. MRAs are getting better. The image quality is substantially improved with better magnets and dedicated wrist coils. And one advantage of the MR angiogram is you can actually evaluate the venous phase. And there are some situations, such as AV malformations or vascular or venous malformations, where it can be helpful to look at the venous phase. In CT angiograms, I find that the radiologists often like to get this. And it's often ordered well. But I find it difficult for the most part to evaluate many of the things that we're looking for in the upper extremity. They're better for high flow lesions. So if you're really looking to evaluate an AV malformation, an AV fistula can be helpful. But for some of the other things that we look at, occlusive disease, CT angiograms, I don't find nearly as helpful. This is an example of an MRA showing an aneurysm of the ulnar artery. You can see the image on the left is the early phase here. This is the late. And so this is what I mean by you can evaluate the venous phase with this. You can get different time points to see what the appearance is. Many of these conditions can be managed medically. So most of the time, they don't need surgery. But there's certainly a process to go through to begin the medical evaluation part of this. And then eventually, if that doesn't succeed, proceed with surgery. So from a medical management for vasospastic processes, calcium channel blockers tend to be a first line treatment. So low dose nifedipine, Procardia. Diltiazem is less potent than the nifedipine, but fewer adverse effects. Tricyclic antidepressants, such as amitriptyline, have been shown to be effective. The selective serotonin reuptake inhibitors are helpful. Alpha-2 agonists, such as clonidine. Phosphodiesterase inhibitors, or Viagra, have been shown to be beneficial. Usually pretty easy to get the males to go for this. A little bit harder to sell to the females. And sometimes hard to get insurance to cover it if you're writing it for a female. The non-surgical alternative, typically when you think of non-surgical alternatives now, we're thinking about collagenase for treatment of dupatrans. But in a similar vein, Botox has been shown to be effective for management of vasospastic processes or vascular disorders in the hand. Typically, you'll inject 100 units into the hand. And so that creates about 20 units per digit. We don't have a lot of science behind coming up with that number. It just happens to be that the vials are 100 units. And so the people that started doing it would divide it one for each digit and come up with 20 units per digit. There's several level four studies, though, demonstrating good pain relief and healing of ulcers, at least in the short term. One of the more recent papers in the Journal of Hand Surgery European Edition from 2014 looked at 20 patients, 100 units of Botox per hand. 16 demonstrated improvement in symptoms, pain relief, and improved dash scores, with 13 reporting less cold intolerance and improvement in the grip, and 18 reporting improvement in their pinch strength. So when you get to the surgical process, now we're looking typically at sympathectomy for the vasospastic processes. And this can either be done proximally in the cervical thoracic region, which has been done historically, but not done nearly as commonly anymore. These are something that thoracic surgeons did, but tend to have a very high recurrence rate and didn't have nearly as good a resolution of symptoms as doing it more distally. And so the three ways to think about it distally are the larich sympathectomy, which is essentially a ligation and resection of the thrombosed vessel, or a sympathectomy where you're removing the adventitia around it. And this can either be done at the wrist and the palm or actually out in the finger. And so the image on the left depicts the palm, as well as the radial and ulnar arteries. The image on the right depicts it being done in the fingers. And I think, for the most part, my preference is to do the procedure described on the left. When you start getting out in the fingers, the fingers become very swollen in this situation, often become very stiff. So I'll typically start more proximally, and only go distally if I've done it proximally and they've had recurrence of symptoms. So an example of a patient, you can see early tissue changes at the tip of the index finger here. Radial and ulnar arteries, you strip about three centimeters of the adventitia around them. Same thing with the superficial palmar arch. And if the thumb or the index finger are involved, you can also do the radial artery in the snuff box. Here's the examples of that. Here we can see hewing. Same thing, this is ulceration along the radial aspect of the index finger, sympathectomies. You can see the palmar arch there. And here early, you can see not resolution, but now you can start to see some granulation tissue, and this becoming red rather than the yellow appearance. So for occlusive disease, often this is a combined process, including both vasospasm and occlusion. As I said, it's related to embolism, thrombosis, or aneurysms. So going back to the question that we asked, what's the collateral circulation like, and what's the sympathetic tone like? So if there's adequate circulation, meaning that you've done your diagnostic test, your digital brachial index ratio is greater than 0.7, well, a reached sympathectomy can work. So that's a simply resection of the thrombose segment of the artery, typically the ulnar artery. If the digital brachial index is less than 0.7, then that supports the need for arterial reconstruction. And there's a variety of things that have been described for this. Angioplasty described, I don't think it's commonly done, but there's a couple of papers that talk about that. And then resection and end-to-end repair, use of grafts, reversal of flow or arterialization of the venous system, and omental transfer, all the things that have been described for this. And so as I said, the decision on what you need to do is based on what your digital brachial index is on your workup. So I said the principle of a reached sympathectomy and the reason that you can just resect the thrombose vessel and actually have improvement in the way it decreases the vasospasm is because the thrombosed artery increases the sympathetic discharge. It can shower distal microemboli, but that increases the sympathetic tone. And by resection of this segment, you decrease the microemboli. You decrease the sympathetic discharge. And so overall, the secondary vasospasm distal to this tends to improve. And so in a situation where you have an adequate circulation or adequate collateral circulation with a DBI greater than 0.7, pretty straightforward from a standpoint of the operation. Just a quick comment about Burgers disease because this has come up on tests occasionally. More common in the middle and the far east, typically males under 40 years of age. Tobacco use is almost always present in this, at least on the test type of questions. And so really, the treatment is to discontinue tobacco use. By and large, stopping the tobacco use will help reverse the process. So going back to what we talked about with the occlusive disease, here's a paper from the European Journal of Vascular and Endovascular Surgery suggesting essentially that angioplasty is feasible. They reported 82% technical success with 65% wound healing. There was poor distal runoff in their series. They admitted to, but did say the procedures can be repeated if there's restenosis. So there's a paper to suggest this, but probably not commonly done, certainly here in the United States. So as an example, 38-year-old left-hand dominant manual laborer, so he's got a dominant hand. You can see changes in the tips of the middle and ring finger, gone on for six months or so, increasing in severity. So you look at the arteriogram, and here's what we have. So you can see flow through the radial artery and the palmar arch here, but nothing, or the deep palmar arch, nothing on the ulnar side of the hand. So why does this occur? So we know the ulnar artery and the ulnar nerve run through Guillain's Canal, essentially between the pisiform and the hook of the hamate, and that's very superficial. It's above the level of the transverse carpal ligament. So any sort of repetitive force or trauma to this area can cause changes in the ulnar artery. And so you get the trauma, and you get one of two things, either periadventitial thickening, which typically will result in thrombosis, or disruption of the internal lamina, which will result in an aneurysm. But either one of these can end up compromising the distal circulation here. So the treatment for this, if you don't have adequate collateral circulation, so your DBI is less than 0.7, is to resect the thrombosis and then reconstruct this typically with some sort of a graft. Here's a clinical example of this. Ulnar artery dissected free. This was a little larger. Usually these areas are about three to four centimeters in size as far as the length of the defect. And so here it is after reconstruction with a vein graft. Aneurysmal disease, so that was the occlusive disease. Aneurysmal disease, questions come up often. The difference in a true and a false or pseudoaneurysm. A true aneurysm typically results from blunt damage to the arterial wall, and the aneurysm contains all layers of the arterial wall. A false or a pseudoaneurysm typically only involves a portion, so not all layers of the vessel wall are involved. And it typically results from a sharp or a penetrating injury, often with small focal areas of dilation. The MRI example here, MRA example of a dilated ulnar artery or ulnar artery aneurysm. Here it is clinically. You can see enlarged, different orientation of it there. This situation, there is enough redundancy of the vessel. We're able to resect this and repair this primarily. And so as typically happens with these, it's always at a junction, so you typically have to do a couple of anastomosis distally, but in this situation, we're able to use the native ulnar artery to repair to the common arteries. When we talk about grafts, there's a couple options or choices for vein grafts. They've been used historically. There's an abundance of graft material, because you have veins essentially all over the body that are expendable. But you have to reverse the veins or remove the valves. And so this can create a seismic match, because the distal portion of the vein is often different from a size. And the proximal portion of the vein, when you reverse it, becomes the distal portion that's anastomous to the artery. And there's a seismic match, and there's thinner walls, so it's a little bit harder to sew an artery to a vein. More recently, arterial grafts have become a little bit more popular as far as a choice. There are some advantages, but there are disadvantages. There's limited graft length that you can get from an artery, and you must have an expendable artery. But there are some that are very helpful for the hand. There's no valves. You don't have to worry about reversing this. And there's a similar size match and diameter, and so it makes it much easier to sew an artery to an artery than a vein to an artery. And often, you can find similar branching patterns to what you see in the ulnar artery of the hand, such as depicted with the Y for the vein. You can find similar patterns for the arteries. So currently, there's no definitive evidence in the hand surgery literature to suggest that one is superior or better than the others. But the idea of using arterial grafts is based on the concept from the cardiac surgeons, and we know that there's higher long-term patency with arterial grafts. That's why they use the IMA as their first choice. They'll often use the radial artery as a choice for an arterial graft, or epigastric arteries. So the graft choices that are typically used for a hand, either the thoracodorsal artery, the deep inferior epigastric artery, or the descending branch of the lateral femoral circumflex artery. These will typically provide a length of about 10 to 15 centimeters, which is good for most things that we're gonna reconstruct in the hand and upper extremity. They have a diameter of about two to three millimeters, so usually a pretty good size match. And particularly, the lateral femoral circumflex artery is helpful because you often have several different branches that you can find along the way, and so you can typically position that. So rather than doing end-to-side anastomosis, you can do end-to-end anastomosis. Here's an example of a case with this. Again, you can see the ulnar artery is not patent at the level of the wrist. To harvest this, the descending branch of the lateral femoral circumflex is essentially at a line between the anterior superior iliac crest and the superior lateral aspect of the patella. Runs in the interval between the rectus femoris and the vastus lateralis muscle. And so, although it's a deeper dissection, it's a pretty straightforward dissection at an interval where many of the orthopedic surgeons are typically comfortable, as opposed to the epigastric artery, which is an area they don't as commonly work. So I think this works very well for this. Here you can see the exposure with the thrombose segment. Resected, you can see the proximal and distal stumps of the artery. And then reconstructed with an arterial graft that was a very good size match. If you look at the outcomes for reconstruction with grafts for ulnar artery thrombosis, there's not a whole lot. But a recent paper from the Mayo Clinic group looked at their vein grafts for arterial reconstruction. They found that 14 out of the 18 had been occluded based on an ultrasound study at an average of 118 months. So good long-term follow-up, showing that many of these don't stay patent in spite of our thoughts or wishes. But in spite of the fact that most of these were occluded, there was no difference in the dash score or the grip strength. The one thing they did note was that the occluded group tend to have more cold intolerance. So when you get past the point of reconstructable disease, kind of what I call end-stage ischemia, most common is calcific peripheral vascular disease, often associated with renal insufficiency. Many of these patients have had amputations in the lower extremities. And so anything that you can do to help salvage their upper extremity can be very beneficial. If you've lost two legs and you lose an arm, it becomes a very difficult situation for them to independently care for themselves. So when you see an arteriogram that looks something like this, where there's some proximal flow and nothing distally, can be very discouraging and very challenging. And so the problem with this, if you just say, well, they've got necrotic fingers, we're just gonna go ahead and amputate these fingers, they don't have adequate vascularity to even heal the amputation sites. There's nothing distal to bypass to, typically. And so the salvage procedures that tend to work well for these, or relatively well, are either a reversal of flow or arterialization of the venous system and freo-mental transfer. So the concept of using a vein for delivery of oxygenated blood to improve the distal perfusion enables the amputation sites to heal. It can often help relieve the ischemic type of pain that doesn't respond to medicines or really any other treatment. You typically use the cephalic or the bacillic vein, and you do have to remove the valves because the vein is left in situ, essentially. And then your proximal anastomosis is pretty straightforward. It's either gonna be to the radial artery, or I like to go up into the brachial artery, because even in situations with advanced vascular disease, brachial artery typically has a pretty good pulse and is a reasonable place to do your anastomosis. Just a clinical example of this, and the patient showed earlier. So you expose the entire cephalic vein, and then you'll make little venotomies through the side, and you'll take out the valves. So you're gonna create a valveless conduit, essentially. So when you do your proximal anastomosis, you can deliver the blood distally. So in a small valvulotome, there's these disposable ones, or a permanent valvulotome. I like the back-cutting ones better than the forward-cutting ones, because these vessels get so small, if you're trying to push, you run the risk of pushing right through the vein. But the back-cutting ones tend to be less of a problem from that standpoint. So here we can see, after we have revascularized this, you can see flow through the vessel. Hopefully it shows up there. So that's the cephalic vein now that blood is flowing through. Amputation sites heal. Another thing associated with chronic ischemia is the Steele syndrome. This is associated with AV dialysis fistulas. Symptoms are often increased in dialysis. And so you need an arteriogram to evaluate for stenosis if you can't determine clinically. So clinically, if they have a palpable AV fistula and they have coolness in their hand or no distal pulses, you can actually just palpate and occlude that fistula. And then with your Doppler, if you can hear better perfusion distally, that gives you a sense that this is really a Steele phenomenon, and that's the reason there's no distal circulation. The treatment for it is to do something to essentially decrease the blood going through the fistula, as depicted here. And so what you wanna do is essentially steal from the fistula to improve the distal circulation. And so sometimes there's just areas of stenosis that you can dilate, and that will allow blood to flow distally. And the other procedure is the DRIL, or distal revascularization and interval ligation. This is essentially just a bypass of the fistula. So you can see the graft coming from here. Now you're bypassing the fistula to allow the blood to flow distally. So the blood's gonna flow down the path of least resistance, and so you just bypass that fistula. Another procedure that has at least been described, but I've not talked to or aware of anybody that has done this. This was in the annals of vascular surgery last year. The ORVIP procedure, or open repair and venous inflow placation. Basically with time, the vein that they use for the fistula dilates. And so they describe removing a segment about three centimeters, so you're decreasing the size of the fistula. This can decrease the flow reduction, and the complications they reported in their paper included high flow resulting in CHF, as well as a pseudoaneurysm. So I think there's probably better treatments for this. In this, you probably want your vascular surgeon or the person that created the fistula involved. So I think I'm out of time. Scott, do you want me to go through a couple of the self-assessment questions for this? So I'll just go through a couple of them. So as I said, several questions that have been asked on this. So in last year's self-assessment exam, 46-year-old female with primary vasospastic disease presents with new onset of ulceration involving the long finger. Examination reveals brisk capillary refill that digits with isolated non-healing ulcer at the tip of the long finger. Digital brachial index measures 0.8. So initial treatment should consist of what? Sympathectomy, injection of Botox, amputation, bypass, or oral calcium channel blocker. DBI is 0.8, so there's adequate circulation. And so in this situation, as I said, often medical management is successful, so you start off with a calcium channel blocker. Another question from last year, 42-year-old female with a four-month history of fluctuating pallor, numbness, and pain following cold exposure in her non-dominant ring and middle fingers. Ulceration formed on the middle fingertip two months ago. Digital brachial index of the middle finger is 0.6. So that 0.6 is going to tell us there's not adequate circulation. Arteriogram demonstrates occlusion to the superficial arch and proximal portions of the second and third web space. Best treatment for this is arterial reconstruction with a vein or arterial graft, resection and ligation of the thrombose segment. So the Loree sympathectomy is good if there's adequate circulation. In this situation, we're 0.6, so that's not an acceptable answer. Adventitial stripping of the superficial palmar arch. Good for vasospastic processes, but not occlusive processes. Calcium channel blocking oral medications. Inadequate circulation with 0.6, so that's probably not good. Topical vasodilatory agents such as nitroglycerin. So in this situation, because the DBI is less than 0.6, you know that you need to proceed with an arterial reconstructive procedure of some sort. Another question. After radial artery cannulation was attempted in the ICU hospitalization, patient develops a mass along the volar radial aspect of the wrist that does not transluminate, so you know it's not a ganglion. Six weeks later, the hiana remains well-perfused, but the patient complains of increasing pain. What is the preferred treatment? So this is a false aneurysm. It occurred from a sharp injury, and so in this situation, it's a pseudoaneurysm or false aneurysm. You resect it and then repair it. Going back to 2014, we'll do a couple of these and we'll be done. Which of the following is generally believed to be the primary regulator of cold-induced vasodilation? The arterial venous anastomosis. Those are the little connections that I showed in the picture. The distal aspect of the fingertips. Patient presents with an ulnar artery aneurysm thrombosis at the hook of the hamate, leading to acute pain in the digits. Digital pressure is 25, so we talked about calculation of the DBI. If the pressure is 25 and you know that a normal systolic pressure in the brachial artery is gonna be much higher than that, this is gonna be pretty low. So your best course of action, ulnar artery reconstruction. In this situation, they recommend an arterial graft. So we'll go ahead and stop here.

chronic ischemia

vascular insufficiency

vasospasm

occlusive disease

diagnostic tests

treatment options