How NPWT Changed Wound Care and Why We Need to Think Like Oncologists

My suite-mate in college used to refer to vacuuming as “Hoovering.” The first manufacturer of technology often becomes synonymous for the technology itself. I still remember the first time a representative from KCI came to talk to me about a device called “The VAC.” That noun quickly became a verb as we all learned what it meant “to VAC” a wound.

I still have the 1997 photos of my first VAC patient, only 2 years after the device was cleared by the FDA. She had an abdominal dehiscence so massive that I could bury my forearms into the area of undermining along the sidewalls of her midline defect. The first time I changed her abdominal dressing I knew that the entire field of wound care had changed. I had already been running a wound center for 7 years. Most of the time, I could do little more than the 16th century barber-surgeon, Ambroise Paré, who said, “I dress the wound and God heals them.”

In 1997, with negative pressure wound therapy (NPWT), it became possible to actually harness the healing process. The first NPWT device was large and bulky and had no battery. I wish I had a photograph of the way one innovative patient created the first “portable” NPWT unit by using bungee cords to attach the heavy device to a skateboard so he could pull the unit behind him, plugged into an outlet via a long orange industrial power cord.

I went to one of the first training seminars for physicians, taught in part by Louis Argenta, MD, himself. In 2016 he received Jacobson Innovation Award from the American College of Surgeons.¹ This recognition was long overdue. More than two decades ago, we used the VAC to revolutionize the management of abdominal compartment syndrome at my level 1 trauma center. In 1999, we tried to calculate the cost savings associated with NPWT for abdominal compartment syndrome, but outcomes were so dramatically improved and the savings so huge, we gave up trying to figure it out.

The recent analysis of 2014 Medicare claims data by the Alliance of Wound Care Stakeholders demonstrated that the dehisced surgical wound is the most common chronic wound among Medicare beneficiaries.² The same analysis showed that dehisced surgical wounds are also the most expensive chronic wound, with most of the costs accruing in the outpatient setting. NPWT is probably responsible for a lot of those costs. As the anticipated 2024 bankruptcy of the Medicare trust fund approaches, there is increasing interest in finding answers to questions like when is the optimal time to discontinue NPWT? What is the ideal suction pressure? Which patients really need incisional NPWT? Some wounds that receive NPWT likely could heal without it, but which ones?

In 2007, the Food and Drug Administration (FDA) demanded that KCI (now Acelity) provide an assessment of the safety of “the VAC” in comparison to moist wound care among patients undergoing NPWT in the home setting. Thanks to the availability of real-world data in the U.S. Wound Registry (USWR), it was possible to analyze the risk of possible complications like infection and bleeding in nearly 1,000 VAC-treated patients, 200 of whom were on Coumadin (Bristol-Myers Squibb), compared to nearly 9,000 moist wound care patients.³ The analysis demonstrated to the FDA that “the VAC” was no less safe than moist wound care in home use.

Perhaps as a result of this experience, in 2009, KCI was alone among wound care manufacturers in understanding the need for a risk stratification system. It partnered with the USWR and Susan Horn, PhD, of the Institute for Clinical Outcomes Research (ICOR) to fund such a project. We had hoped to create one model that worked for all wound types but, because different factors affected different wound types, 7 models were ultimately developed, one for each major ulcer category. Termed the Wound Healing Index (WHI), the nearly four-year project involved analyzing the structured data from almost 70,000 wounds in the USWR, identifying individual factors associated with failure to heal, creating predictive models and validating them from additional data.^4–6

The WHI makes it possible to predict with reasonable accuracy, at the conclusion of the first visit, whether a wound of a given type is likely to heal with standard wound treatment alone. Using the WHI, it is not necessary to wait weeks to establish a wound healing “trajectory.” The WHI allows the early identification of patients who will likely need an advanced therapy like NPWT to achieve healing, or perhaps more importantly, those who do not, allowing better targeting of healthcare resources. It is interesting to consider that despite all the hype about using artificial intelligence (AI) in wound care by analyzing photographs, there is no apparent interest in using the AI currently available in the form of predictive models. When KCI helped fund the WHI project, the planned second phase was to identify the factors that predicted the likelihood of benefit from advanced therapeutics such as NPWT. The recent analysis of the cost of chronic wound care suggests that this second phase should still be undertaken.

The most important impact of the WHI is to enable the honest reporting of healing rates to Centers for Medicare and Medicaid Services (CMS). A recent systematic analysis found that the vast majority of hospital based wound centers publicly report healing rates better than 92% in less than four weeks.⁴ The contradiction between nearly perfect healing rates and the multibillion-dollar cost of treating chronic wounds creates a looming crisis for the field of wound care. CMS has implemented the Quality Payment Program (QPP). The majority of practitioners are now subject to the Merit Based Incentive Payment System (MIPS) under which a practitioner’s Medicare Part B payments can be assessed either a bonus or a penalty based on a complex formula that includes quality performance (e.g., outcomes reporting) and per patient spending. Under MIPS, CMS requires that patient outcomes be reported using “risk stratification,” which is why virtually every medical specialty has developed a risk stratification system.

Given the realities of the QPP, it’s time for wound care practitioners to think more like oncologists. Reputable cancer centers do not report that they cure 92% of all cancers. Thanks to the transparent and uniform way that oncologists report outcomes, we know that whether patients are likely to be cured of their cancer is determined in large part by the type they have and the stage at which cancer is diagnosed. The higher mortality rate of more aggressive cancers is not interpreted as an indictment of the oncologist, but an argument for developing better treatments.

Similarly, wound care practitioners should brag about their healing rates in relation to the predicted likelihood of healing. We should be reporting the outcome of the most difficult patients, not the easiest ones, if we want to justify the need for our services and the cost of care.

In 2014 the USWR was among the first Qualified Clinical Data Registries (QCDRs) recognized by CMS. There are currently 11 wound care relevant quality measures approved by CMS as part of the USWR MIPS registry, two of which are the healing rate of diabetic foot ulcers (DFUs) and venous leg ulcers (VLUs). In March of 2017, a few forward-thinking wound care practitioners reported the healing rate of diabetic foot ulcers and venous leg ulcers to CMS as part of their MIPS participation. These healing rate measures were stratified by the WHI. They didn’t report healing rates of over 92%. They reported honest healing rates, which in some cases were 60%, because the patients they cared for were so complex. CMS rewarded them with the highest quality measure score possible under MIPS.

Although we all think of “the VAC” as the most important accomplishment of the company previously called KCI, history will probably show that enabling the development of the WHI was just as important to the field of wound care. Last week a private payer denied NPWT to yet another of my patients with a dehisced surgical wound. She has a genetic disease that affects collagen production, and adult onset diabetes. Using the WHI, I can prove her wound probably won’t heal without NPWT, but sadly, using the WHI to justify the need for NPWT hasn’t been promoted, even though that’s the very reason the WHI was created.

I predict that it will become harder and harder to get NPWT approved by private payers, and that includes patients with Medicare Advantage. Without using the WHI to justify the need for advanced therapeutics like NPWT, the future of wound care could look like it did in the early 1990s: dressing the wound and praying for patients to heal.

Caroline E. Fife is Chief Medical Officer at Intellicure Inc., The Woodlands, TX; executive director of the U.S. Wound Registry; medical director of St. Luke’s Wound Clinic, The Woodlands; and co-chair of the Alliance of Wound Care Stakeholders.

 

1. American College of Surgeons. Available at https://www.facs.org/media/press-releases/2016/argenta060616 .
2. Nussbaum SR, Carter MJ, Fife CE, DaVanzo J, Haught R, Nusgart M. An economic evaluation of the impact, cost, and Medicare policy implications of chronic nonhealing wounds. Value Health. 2018; 21(1):27–32.
3. Fife CE, Walker D, Thomson B, Otto G. The safety of negative pressure wound therapy using Vacuum-Assisted Closure in diabetic foot ulcers treated in the outpatient setting. Int Wound J. 2008; 5(Suppl 2):17-22.
4. Fife CE, Eckert K A, Carter MJ. Publicly reported wound healing rates: the fantasy and the reality. Adv Wound Care. 2018; 7(3):77–94.
5. Horn SD, Fife CE, Smout RJ, Barrett RS, Thomson B. Development of a wound healing index for patients with chronic wounds. Wound Rep Reg. 2013; 21(6):823-832.
6. Fife CE, Horn Susan D, Smout RJ, Barrett RS, Thomson B. A predictive model for diabetic foot ulcer outcome: The Wound Healing Index. Adv Wound Care. 2016; 5(7): 279-287.