When Robert Cuff, MD, and Max Wohlauer, MD, first launched the Vascular Surgery COVID-19 Collaborative (VASCC) back in the spring of 2020, the pandemic was still in its first wave, and the goal of a new vascular surgery registry to leverage key data with the the goal of preparing for the fallout from future outbreaks was in its nascent stages.
Fast forward to the waning weeks of 2021, as the Omicron variant ravaged the globe, and Cuff, Wohlauer and a burgeoning team of VASCC collaborators were already counting the positive impact of interim data gathered from one of two core VASCC projects.
One of the most interesting aspects of the data emerging out of VASCC Project 1—covering the impact of COVID-19 on scheduled vascular operations—so far surrounds its use outside of the pandemic context, explains Cuff, a co-founder of the registries with Wohlauer.
“At our institution, we’ve been delaying a lot of surgeries, not necessarily because of our COVID numbers, but because we’re facing a large nursing shortage and therefore our bed capacity has decreased, as we don’t have people to take care of them,” says Cuff, program director for integrated vascular surgery residency at Spectrum Health-Michigan State University in Grand Rapids, Michigan.
“This is a nationwide problem. Every surgeon I have talked to is facing the same issues. So although the data that we gather in VASCC is on delays due to the pandemic, that data is going to be helpful in determining what patients should be delayed for in other situations like the one we’re facing now.”
It comes down to weighing competing priorities, Cuff explains.
“We have several aneurysm and open surgery patients who have been delayed for almost a month from their originally scheduled surgery, and this data that we developed was actually helpful in trying to figure out: should we move them up regardless, versus patients who have carotid disease or other disease,” he says.
“Maybe we can delay them a little longer in order to use beds as wisely as we can. So this is not just applicable to the pandemic or the COVID situation, but it is actually providing a framework for looking at delays for any reason that may be outside of a short-term situation for a few days, to help give guidance as to which patients may have to be treated sooner or later when it comes down to a bed crunch.”
Interim data presented at fall 2021 meetings
Fellow co-founder Wohlauer, a vascular surgeon at the University of Colorado-Anschutz in Aurora, Colorado, summarized interim results delivered at high-profile vascular meetings in the second half of last year, giving some insight into the type of findings Project 1 yielded. “At VAM, we presented our interim data analysis for aortic disease, chronic limb-threatening ischemia [CLTI], venous disease and end-stage renal disease [ESRD], and at the European Society for Vascular Surgery [ESVS] annual meeting, our impact on carotid disease interim data analysis—and we found some interesting things,” says Wohlauer. “We found that the overall mortality in our aortic group was about 5%, ESRD was about a 6% perioperative mortality, and I think 2% or maybe 4% died while waiting for their surgery. We found that patients with CLTI had about a 4% risk of decompensating while waiting for their operation, and that those patients who required an emergency surgery did very poorly—about 60% of them ended up having an amputation. We found in this group of patients with CLTI that diabetes has a strong association with major adverse limb events. And we found that, overall, with venous and carotid procedures in our cohort, patients were postponed and rescheduled with minimal complications.”
The international breadth of the VASCC endeavor has opened doors and broken some fresh ground, while also posing unique challenges. Alongside Project 2, which is focused on thrombotic complications of COVID-19, Project 1 lives at three separate locations, which each governing specific geographical area for the VASCC registries: the European hub in Rome, Italy, led by Giovanni Tinelli, MD; the U.S. hub at the University of Colorado; and the international hub, managed by Susan Heard at CPC Clinical Research, which is affiliated with the University of Colorado. While Project 1 looks at outcomes following delays to vascular procedures related to the virus (across the five modules of carotid, aortic, peripheral, venous and hemodialysis), Project 2 probes COVID-related thrombotic issues in cases of acute limb ischemia (ALI), acute mesenteric ischemia, symptomatic venous thromboembolism (VTE) and stroke.
Data privacy concerns and regulatory differences across borders complicate the management of a VASCC database that spans the U.S. and Europe, Wohlauer says. The single database at three locations is aimed at facilitating widespread participation among vascular surgeons from different countries, practice types and levels of seniority in order “to get a sense of what’s happening around the world with patients whose surgeries were postponed during the pandemic,” he shares.
Chiming in from Italy, Tinelli lauded the international scope of the collaborative. “This is a great opportunity to create a real network in Europe and around the world,” he says. “VASCC is a great opportunity inside the COVID pandemic because the real great solution from the vascular registry is that it is taking place during the first, second, third and now fourth wave.”
Mahmood Kabeil, MD, a research scholar at the University of Colorado assisting the VASCC projects, highlights the far-reaching nature of the surgeons and institutions inputting data—from Ireland to Australia and multiple points in between. The latest involvement numbers show around 250 sites in almost 50 countries, and “the collaboration is growing,” Kabeil discloses.
As manager of the international hub, Heard—CPC’s clinical data manager—says VASCC is treading largely virgin territory in terms of information gathering. “To my knowledge, this is a fairly novel approach in terms of using REDCap as our data collection tool. Because we have three completely separate instances in three different locations but we’re using the same database structure, as any changes need to be made, it’s very easy for us to be able to do that so that our databases continue to sync as we are collecting data separately but together.”
Ethan Moore, a research assistant at the University of Colorado assigned to work on VASCC, detailed a list of physician meetings drawn from disparate locations across the globe—recently Ireland and Indonesia, later Japan and Australia—that proved an eye-opening experience in terms of the vantage point they provided into how different countries are dealing with the pandemic at different times depending on their local circumstances. “It offers a real-time opportunity to look at each country and see how they’re dealing with it,” Moore adds.
Perioperative risk stratification
Meanwhile, as VASCC looks ahead, Kathryn Colborn, MD, an associate professor at the University of Colorado and biostatistician working on the registries, details the use of a novel risk stratification system developed within thoracic surgery named the Surgical Risk Preoperative Assessment System (SURPAS).
SURPAS utilized American College of Surgeons National Surgical Quality Improvement (ACS NSQIP) data to develop a preoperative risk surveillance system, she explains. In short, it involves a logistic regression model with eight variables collected at the preoperative visit to estimate the risk of 12 postoperative complications, thus producing a risk score.
The system helps in a number of ways, Colborn explains, such as enabling discussion with patients preoperatively about their risk and also to risk adjust rates postoperatively.
“The goal for VASCC was to incorporate SURPAS so we could estimate observed-to-expected event ratios in these patients,” she says. “In some patients, we might expect certain complications. But if we can evaluate their preoperative risk, we can evaluate whether we had higher-than-expected event rates in this population.”
Meanwhile, Wohlauer describes a specialty equipped to deal with the vagaries of COVID-19. “In vascular surgery, we are like cobblers—each shoe is a little different. That’s how we see ourselves,” he says. Ultimately, VASCC is a team effort, Wohlauer reflects, and what the research aims to do is use high-quality data to understand best practices, and in which situations a certain operation works best.
“There are clinical trials like BEST-CLI that are helping answer these questions as well. I think they are really healthy for our community to be answering these questions in this way,” he continues.
“This organization shows we can custom-build a database to answer a specific question, and that harmonizes with the important work national registries do, which have less plasticity—and they collect orders of magnitude more data than we do.”
VASCC also demonstrates a proof of concept, Wohlauer says. “The projects that we’re completing right now show this proof of concept: taking a working group of experts in the field, making sure we have diverse representation of views— seniority, gender, ethnicity, country of origin—to make sure we’re asking the questions the way we want to answer them; spending a lot of time with our registry managers building the registry; and also thinking a lot about the data analysis before even looking at the data.” All of this was accomplished during a time of great limitation—not only on procedure scheduling, but on doing research, he adds. “We found a way to do it.”