Transradial Access at the University of Miami
Dr. Mauricio Cohen has been performing transradial access procedures for approximately 5 years. After joining the University of Miami Hospital cath lab in January of 2009 as director, he instituted a transradial program.
Dr. Cohen, where did you first learn transradial access?
I was exposed to these procedures during my training in Argentina back in the mid-1990s. In 1994-95, we did a randomized study looking at radial, brachial and femoral access, and it was during this study that I was exposed to transradial access. I learned the nuts and bolts of the transradial procedure, but did not incorporate it into my practice until ten years later.
What’s your sense of how transradial access is utilized in Argentina?
I believe it is used slightly more than in the U.S., but not quite as much as in high-use countries like France, Canada, Spain or Sweden.
How often do you use transradial access in your current practice at the University of Miami?
I use it in 80-90% of my cases. When I approach a patient, the first thing I do is check the radial pulse. My mindset is that every patient is a candidate for transradial catheterization, unless contraindicated. Therefore, every patient is a radial case by default.
What are some of the reasons not to use the transradial approach?
There are very few contraindications for transradial access. These include the presence of an occluded radial artery, usually secondary to a previous procedure; lack of radial pulse; hemodialysis with an arterio-venous (AV) fistula in the forearm, and an abnormal Allen’s test. It is worth mentioning that we perform the Allen’s test using pulse oxymetry and plestismography to test the patency of the palmar arch. With this technique, less than 2% of patients will have an abnormal test. If there is previous coronary artery bypass graft surgery with a left internal mammary artery (LIMA) graft, we can puncture the left radial artery. As a matter of fact, engaging the LIMA is fairly simple and safe with this approach. If a patient has an occluded right radial artery, we will use the left radial artery, and then if we are unsuccessful, we will use a femoral approach.
How often do you find that you are converting to femoral access after beginning with a radial approach?
I’d estimate that occurs in less than 5% of cases. A common reason is tortuous anatomy. A tortuous subclavian would preclude access of the catheters to the ascending aorta. However, there are very few cases in which I have to convert because we are now able to negotiate the significant tortuosity associated with radio-ulnar loops, spasm or other problems that may present. I do think my rate of femoral conversion is actually decreasing.
How do you solve the problem of tortuosity?
It is important to keep in mind some basic rules when you do radials. You never push. Every procedure must be done with finesse. When we find that the wire is not going where it should be going or feel unusual resistance, we take a limited angiogram that will allow us to uncover the problem — anomalous anatomy or severe spasm. If it’s severe spasm, then we will give more vasodilators such as verapamil and nitroglycerin, and sedate the patient more. If it is a true anatomic problem, then we can sometimes use smaller wires and different catheters, such as a hydrophilic-coated catheter, to navigate the tortuousity, and then exchange for a stiffer wire that will straighten the vessel. Sometimes, when we cannot negotiate the tortuosity, we will convert to transfemoral access, but this is a rare occurrence. It is important that within one’s learning curve, the inexperienced operator be aware of his/her own limitations and convert to femoral access before causing a vascular perforation in case of very tortuous anatomy.
In general, we use 3 mg of intra-arterial verapamil in every case right after inserting the sheath. We use a dedicated access kit with a hydrophilic-coated sheath. It goes into the vessel very smoothly and I think it is less traumatic, so that’s an additional factor to prevent spasm. Sometimes we need to use additional doses of sedatives to prevent the adrenergic release associated with anxiety. We see spasm in 5-10% of cases, but in the past six months, I haven’t seen spasm severe enough to make me switch the access site.
When patients have severe vasospasm and severe pain, it may be a sign that there is a vascular anomaly, such as a radio-ulnar loop. Sometimes the catheter may have gone through a communicating vessel between the ulnar loop and the brachial artery. This communicating vessel is usually very narrow and reacts to the catheter with severe spasm. In these cases, when the patient feels severe pain, a limited angiogram helps us understand the problem.
When you are presented with challenges during radial access, why go the extra step of trying to work through them? Why not simply convert to femoral access?
We put in additional effort because the patient already has arterial access and because we believe that transradial access adds significant safety to the procedure. If you think you can safely negotiate the tortuosity, and feel confident it can be done with the equipment you have, I don’t see a reason for not doing so.
Is there a problem with excess contrast with transradial access?
It depends. Many studies have shown that transradial access increases radiation exposure to the physician, as sometimes the cases are slightly longer. I believe that any additional radiation exposure is offset by the significant benefit it delivers in terms of patient outcomes. What we also need to keep in mind is that if you don’t commit to using transradial access on a regular basis, you will never become truly proficient at it. The more you do, the better you become. Using a one-catheter technique, I can complete a transradial case in as little as two to two-and-one-half minutes when working alone, as I don’t need to exchange catheters to selectively engage each coronary artery. When I am the operator, I believe the radiation is at the same level as when I utilize femoral access.
There is no question that a set of skills are needed to become proficient in transradial access. It takes about 100-200 cases to become experienced. A skilled operator with good hands can master the technique much faster. One of our fellows was first exposed to transradial access when he started to cath with me. By the end of his one-month rotation, he was independently performing a complete transradial case. I was not scrubbed in. This fellow has very good hands. He got access, engaged the right and the left coronary artery with the same catheter, and then finished with a ventriculogram. I was very pleased. So both skills and a positive attitude are necessary for the adoption of this technique.
Do you prep the femoral access site even when you are planning to do transradial access?
It depends on the situation. I always evaluate the patient before the procedure to determine if a groin prep is required. I recently treated a male patient who was fairly young. He had a very good radial pulse and the nurses asked me if I wanted the groin prepped. I said no, as I did not foresee any problems getting radial access. On the other hand, when I see a “little old lady” with a weak radial pulse or a patient that is clinically unstable (i.e., STEMI), I may request a groin prep as back up.
Some have said that women have a higher conversion rate (to femoral access), but they are also the ones who benefit most from transradial access.
You would think that women with their smaller body size and smaller radial arteries would have higher conversion rates, but I haven’t seen that in my experience. In fact, I’m not sure that this has been well-described in the literature. But you are right about the benefit, because female gender and older age are two major risk factors for bleeding. If you eliminate the vascular access site as the source of bleeds, then you eliminate 60-70% of the chance of bleeding. Registries have shown that 60-70% of the bleeds that occur after transfemoral percutaneous coronary interventions originate from the vascular access site.
Do you perform ST-elevation myocardial infarction (STEMI) cases with transradial access?
Transradial access is substantially beneficial in these cases. STEMI patients receive a large bolus of heparin in the emergency room and we use GP IIb/IIIa inhibitors in the cath lab. Therefore, they are at high risk of bleeding. At University of Miami, as well as in my previous position at University of North Carolina at Chapel Hill, I have been performing more than 50% of my STEMI cases transradially. Some of our STEMI patients are transported by air from the Florida Keys straight to our cath lab having received at least one bolus of thrombolytic therapy. Therefore, transradial access is very convenient and safe in these cases.
Have you noticed a decrease in your bleeding complications?
Anecdotally, I believe this is the case. I have not looked at enough of our data yet. There is no question that patient comfort is much better and patient length of stay is much shorter. Equally important, when I go home at the end of the day, I am very confident that patients are not going to bleed and I will not be called in the middle of the night because the patient is having a huge groin bleed or has developed a life-threatening retroperitoneal hematoma. This confidence gives me peace of mind.
How does the transradial approach affect scheduling in your cath lab?
Transradial patients have a significantly shorter recovery period. They can get up right away and do not need assistance to go to the bathroom. Obviously, there is a decrease in nurse workload, patients go home sooner and the flow improves substantially. Sometimes we have to bump patients scheduled in the morning because an acute case presented to the emergency room. We then have to do these elective patients by the end of the day. Transradial access in elective patients is greatly advantageous because these patients can generally still go home as a result of this access strategy. If we did these cases via femoral access, then we have to admit them overnight in order to watch their groin. Another situation is when a patient is admitted with chest pain and we have to rule out an MI. Even after three enzymes are negative, a physician may still feel that the patient should have a cath. We do the cath transradially, so that if the patient does not need an intervention, the patient can go home immediately following the cath. Transradial access generally allows the patient to leave on the same day, therefore avoiding a night’s stay.
The cath labs at University of Miami are used by a wide range of physicians. Have you seen any interest across the various disciplines regarding transradial access?
The beauty of this cath lab is that we all interact well. There’s a very friendly relationship among physicians of different specialties and subspecialties, including vascular surgery, vascular interventional radiology, interventional cardiology and electrophysiology. We also have an aortic valve program and some of the cases are done in a hybrid cath lab with the help of a surgeon, since these cases need transapical access. As yet, I have not been able to do cases with physicians of other specialties, but it is definitely in the works. Several vascular surgeons and interventional radiologists have expressed interest in the transradial approach. We also have a few “interventional nephrologists,” who are also very interested in the technique.
You mentioned that you train fellows on radial access and they are mostly enthusiastic about it. Will the next generation be more comfortable with this procedure?
I hope so, but I don’t think that the large majority of training sites are teaching fellows how to do it. We are training them and, as they gain experience, they become very enthusiastic about radial access. I have actually developed a “transradial approach tutorial” with pictures, so the fellows can see, step by step, how it is done. Then, they join me in the cath lab and see one or two transradial procedures. Next, I give them the first operator post, and I expect them to get access and start gaining hands-on experience on how to navigate through the vasculature of the upper extremity until they reach the ascending aorta with the catheters. Some of them learn fairly fast. Two of the fellows that I trained at the University of North Carolina are now in practice and actually using transradial access as a marketing tool to obtain more referrals and be known in the community where they practice.
Radial access is not a fancy procedure that is performed once in a while. This is a modality that can be incorporated into 99% of your patient practice. The patients we see every day in the cath lab are generally those that require a coronary angiogram and a left heart cath. You can incorporate the transradial technique into your practice, immediately convert the majority of your cases to transradial procedures and increase the safety of your patients.
Joey Collazo became the chief technologist at University of Miami cath lab in September 2008. He has been involved with transradial access for the past 7 years.
How did you train staff on the transradial approach?
We started training a few months before Dr. Cohen arrived, practicing with various staff as the “patient.” I trained one staff member a month, both the technologists and the nurses. We went step by step, beginning with the Allen’s test and going through the whole procedure. Our staff learned how to position the arm board and handle equipment used for transradial access. We trained hard and created a checklist for our staff to ensure they knew which wires and catheters to use in a transradial case. As a result of our training, I believe our team can fully support a case, including any complications that might present.
What was the reaction when the program began?
Staff loved it. While we trained hard, the training was relatively easy. Actually, I would say our doctors are also becoming more engaged in transradial access.
Interestingly, I am seeing more and more patients ask if they are getting radial or femoral access. They are learning a lot through articles and word-of-mouth discussions. A significant number want radial access.
[Dr. Cohen: Today I had a case that we did transradially. The case went smoothly and easily. Staff and I are getting to the point where communication is non-verbal. They already know what I need and expect. As an endorsement of the transradial access among my team, some of the staff members came to me and said that if they ever need to have a cath done, they want me to do it using transradial access.]
What’s your sense of the program overall?
Overall, I think it is excellent. More staff and more fellows are getting trained. I have been working in the cath lab for 19 years, and I have noticed that transradial access is much easier on the patient. We see fewer complications with transradial access than we see with groin access. If you go through the femoral artery, it is possible to hit a nerve, making it more painful for the patient. Using the radial artery also means less bed rest time for the patient. Patients can walk around almost immediately after the procedure. For staff, it means less time, because, for instance, prepping the radial site is a lot quicker than prepping the groin.
Before we bring the patient in the room, the first thing we do is an Allen’s test, to make sure the radial artery is usable, with adequate blood supply to the hand through the ulnar artery. Next, we will call Dr. Cohen or whoever is doing the procedure to let them know that the Allen’s test was okay for transradial access. We do always shave the groins just in case there is any reason to convert to femoral. We prep both the radial and the groin, unless the doctor feels 100% about his ability to perform the case using radial access.
What about post-procedure care?
Once the procedure is done, we put on a TR Band (a radial compression device) and give the patient a couple hours wearing the band. Dr. Cohen requires the patient to walk right away after the procedure. They actually walk from the procedure room, which is beneficial to their recovery. Walking around allows patients to feel more comfortable and independent, and less nervous. They love it.
Have you also given inservicing to staff outside the department?
Yes, every single floor in this hospital has been trained on the transradial procedure and how to use the TR Band, including how to take it off. They have also been trained to handle potential complications.
How are things different at the University of Miami from your previous position?
There was only one doctor at my previous position who was performing transradial procedures. At University of Miami, we actually have a number of doctors who are now performing transradial procedures. They know they can rely on Dr. Cohen during a case, if his assistance is needed. He’s our resident expert.
What have been the benefits to the cath lab that you’ve seen from transradial access?
It means less time for patients to be in the hospital. They don’t have to be lying flat for 4-5 hours. Also, we are using a lot less equipment. For example, using transradial access, we can perform a basic diagnostic procedure with a single catheter, as compared to three catheters when going through the femoral artery. It’s a cost savings for the department.
Kym Manni is Associate Vice President of the cardiovascular service line at the University of Miami Hospital.
How many cath labs are in the University of Miami cardiovascular service line?
We currently have five cath labs and 24 staff members. We are constantly recruiting and currently have 10 openings. We can’t build this program fast enough. We have a multi-disciplinary staff of physicians that use the cath lab: vascular surgeons, open-heart surgeons, interventional radiologists, cardiologists and electrophysiologists. There are at least 60 physicians with privileges in the cath lab.
What are your thoughts about transradial access?
Radial access has been around for a number of years. Most physicians were typically trained to perform the femoral approach, so in my past experience, transradial would only be used if we couldn’t get femoral access. The University of Miami is the first lab I’ve worked in with a physician whose preference is to do procedures transradially. For all of us who have been in the business for a number of years, access has always been through the groin, so by default, that was the habit. Rethinking and implementing a new access strategy is challenging. Yet, once mastered, it offers many benefits, including additional patient safety factors, immediate patient ambulation post procedure and the potential for early patient discharge from the hospital. Regarding patient ambulation, this contrasts against a patient having to lay flat for four hours or more post procedure with a transfemoral approach. In our institution, we treat a number of patients from the Florida Keys, which is a four-hour drive from Miami. By using a transradial versus a transfemoral approach, we are able to treat and discharge patients much quicker, often enabling them to make the long trip home before dark.
What have you seen happen from a financial perspective?
Financially, there is a significant cost reduction for radial access versus femoral access, both in terms of equipment used and length of stay, which benefits from quicker ambulation post procedure.
Interestingly, Dr. Cohen’s overall cost per procedure is roughly $2,000 less than his counterparts using transfemoral access. Physician cost per procedure is something that we’ve only recently started to keep track of; the university has only owned this hospital for a little more than a year. These things are now being tracked and are shared with physicians through our cath lab committee.
We still use the same number of staff per procedure. Ultimately, I think the biggest benefit is patients being discharged sooner. They can ambulate much quicker, and we don’t have all the groin complications with closure devices or groin bleeds, so from the patient safety standpoint, that is where we see the biggest benefit. Patients can have a post-procedure bleed with femoral access. They can require care for a pseudoaneurysm. We have not seen any complications with our transradial program.
Dr. Mauricio Cohen can be contacted at email@example.com
Joey Collazo, RCIS, can be contacted at firstname.lastname@example.org
Kym Manni, RCIS, PhD, can be contacted at email@example.com
Summarized Policy for Transradial Access at University of Miami Hospital Cardiac Catheterization Hospital
• The use of transradial arterial approach in the cardiac catheterization laboratory is at the discretion of the attending interventional cardiologist.
• All catheterization laboratory personnel will be familiarized with this approach through in-service education and review of the unit procedure manual.
• The advantages of the transradial versus transfemoral approach include, but are not limited, to: immediate patient ambulation, dual blood supply to the hand associated with a decrease in vascular complications, easily compressed vessel, less risk for nerve injury and patient preference.
• Radial access should be strongly considered in patients who are morbidly obese or have significant coagulation disorders, or with severe peripheral vascular disease without femoral access.
• The contraindications of the transradial approach are abnormal modified Allen’s test, patients who require intra-aortic balloon pump (IABP) counterpulsation, known upper extremity vascular disease, patients on hemodialysis with arterio-venous (AV) fistulas in the upper extremities, and pre-existence of internal mammary grafts contralateral to the site of entry.
Supplies and Drugs Needed for Transradial Approach
Oversized Plexiglass arm board
“Brachial” sterile drape
Glidesheath Access Kit (6 French) (Terumo Medical Corp., Somerset, NJ)
Stiff Shaft Glidewire – 260 cm length, angle tip (Terumo)
Verapamil: vial of 5 mg (2 cc)
Nitroglycerin spray (to administer SL per physician request)
Heparin 5000 units or 60 U/Kg bolus
TR Band (have regular and large sizes readily available) (Terumo)
Sheath Removal Protocol
The following steps should be followed to obtain hemostasis:
1. Clean the wrist area with sterile saline
2. Withdraw the sheath approx. 2-3 cm
3. Align the green marker, which is located on the center of the compression balloon, to the puncture site and fix the belt on the wrist with the adjustable velcro fastener.
4. Inflate the balloon by injecting 15 cc of air through the one-way valve in the side port using a special syringe provided with the kit. Do not discard the syringe, as it will be used at a later time to deflate the device. Keep syringe in a plastic bag attached to patient’s chart.
5. Remove the sheath as the balloon is inflated.
6. Slowly withdraw air from the TR Band 1 cc at a time, until there is blood oozing from the puncture site, at which time 1 cc of air can be re-injected into the balloon.
7. Use sterile gauze or swab to wipe any excess blood from underneath the TR band.
8. Check capillary refill and pulse oximetry of the affected hand after the device is secured.
Nursing Assessment in the Holding Area
• Monitor site for bleeding, hematoma, or ischemia.
• Place sensor for continuous monitoring of pulse oximetry in the affected hand.
• Check capillary refill every 15 minutes x 4, every 30 minutes x 2, every 1 hour x 4.
• The patient can sit in a chair and ambulate to go to the bathroom immediately after transfer to the holding area.
• Assess patient’s pain level, administer pain medications if ordered.
• Notify the physician if:
o Any problems arise, especially the presence of arm pain.
• Vigilance for the development of forearm hematoma associated with pain is extremely important. Accumulation of blood in the forearm can cause compartment syndrome and severe hand ischemia. Therefore, prevention is crucial. Notify the physician immediately and have elastic bandage or tape ready (ACE bandage or Elastoplast).
o Any uncontrolled bleeding (elevate the arm and apply manual pressure should this occur.)
o Circulation to the hand appears compromised.
• Removal of TR Band
o After approximately two hours, gradually deflate the device, 1 cc at a time, using the syringe provided in the kit. Remove 5 cc of air and observe the access site carefully for any bleeding. Then remove 5 cc of air every 15 minutes thereafter until the device is completely deflated.
o If bleeding occurs while deflating the device, re-inject 1 cc air until the bleeding stops and wait another 15 min before repeating the steps above.
o Once the TR band is completely deflated, confirm that bleeding has stopped, remove the device and place a protective covering (i.e.: band-aid, tegaderm, etc.)
• Assess perfusion to the hand (color, temperature, sensation) with vital signs.
• Instruct the patient about movement and activity restrictions. The dressing should be left intact until the next morning. The patient should minimize manipulation of the wrist for 24 hours. After the dressing is removed, the site may be gently cleansed with soap and water.