Published On March 14, 2019
HECTOR MORALES ROUTINELY CHECKS HIS FEET. His diabetes causes high glucose levels in the blood, which can damage blood vessels and nerves, meaning that it is both harder for him to notice a wound and harder for his body to heal it. Infected foot ulcers are the most common reason that patients with diabetes end up in the hospital, and those with nonhealing wounds face grim odds, with about one in five undergoing the amputation of a limb.
While the about two-thirds of amputations are performed on people with diabetes, they can also result from vascular diseases or traumatic injuries. More than 500 Americans a day lose an upper or lower extremity, and the number of people with amputations is expected to double by 2050.
Losing a limb is a life-altering event, and related problems and costs can be staggering. People with amputations struggle with chronic pain, additional wounds related to prostheses and falls, further hospitalizations and far lower rates of survival at the five-year mark than patients with many types of cancer. Lifetime health care costs for an amputee are estimated to be nearly double those for the average person. There are also indirect costs, such as making a home more accessible or losing a job.
Because of this, amputation has gotten a fresh wave of attention as something to be studied in and of itself and headed off, with its own specialized toolbox. Some progress is surgical, and much is the result of advancing technology. With ultrasound and other medical imaging now doing a better job of pinpointing compromised blood vessels, surgeons have more options for clearing away small blockages, including inserting a catheter into the groin or a limb, and using techniques and devices—stents, balloons, lasers—normally used to clear central arteries. Some of these repairs can happen using local anesthesia.
Machine learning also plays a role. A project at Duke University looked at the records of 17,000 patients with diabetes and was able to evolve a model that could predict—with 90% accuracy—when a patient might require an amputation in the next year. With that kind of lead time, a host of interventions and preventive strategies can be put in place.
But one of the most important advances may be administrative. Increasingly, hospitals are creating collaborative limb-salvage teams—also known as limb-preservation teams—as a new standard of care.
“Over the past three to five years, almost every major health care organization has either started a team or is attempting to do so,” says Joseph Mills, a vascular surgeon and medical director of the Diabetic Foot and Wound Care Center at Baylor St. Luke’s Medical Center in Houston. The Society for Vascular Surgery and the American Podiatric Medical Association have also been catalysts, encouraging a multidisciplinary approach to limb preservation.
Mills has been a pioneer. He helped develop Baylor’s “toe and flow” team (Save the Extremity Program, or STEP), which brings together podiatrists—the toe experts—and vascular surgeons, who are responsible for improving blood flow to the affected limbs of patients with diabetic foot issues. These specialists don’t often collaborate, says Mills, but the pairing allows more rapid and effective care and helps avoid delays that can be created when consultations and communications aren’t coordinated. “These are often complex patients—people who in the old model would have to have had multiple visits with many different physicians and diagnostic tests to determine and carry out a treatment plan,” he says.
These multidisciplinary teams may be able to help develop more standardized strategies to avoid amputations. Determining when a given impaired limb is beyond salvage can be a very challenging clinical question, and there is a real shortage of consensus and data to guide treatment decisions, says Matthew Menard, a vascular surgeon at Brigham and Women’s Hospital in Boston. Menard is a principal investigator in a large, randomized clinical trial involving more than 134 medical centers and nearly 2,100 patients that is looking at how to address impaired blood flow to limbs. The trial will evaluate various treatments but also serve as a way to share information. “A multidisciplinary approach is a big component of the trial,” Menard says. “We know there are great benefits of having physicians with different skill sets assessing a given patient together.”
Hector Morales did eventually sustain a foot injury related to his diabetes, and within hours of arriving at the emergency room of Adventist Health White Memorial Hospital in Boyle Heights, Los Angeles, he was evaluated by a multidisciplinary team. Specialists in podiatry, vascular disease, infectious disease, endocrinology and cardiology gave their opinions. Morales was in surgery by the next morning. “If I had waited another 12 hours, my foot would have been amputated,” he says. Within a few months he was fully recovered and back on both feet.
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