Building A Better ‘Mousetrap’ For NPWT

Kathleen Satterfield DPM FACFAOM

The proof that a perfect solution has been achieved is when you don’t see a lot of other products on the market for a particular problem: it’s called building the better mousetrap.

It seemed like KCI’s Vacuum Assisted Closure therapy (VAC® therapy) was just that for more than a decade. I had been a believer for multiple reasons as a wound care provider and unfortunately as a patient with a large abdominal wound. How often on the foot do we see wounds of the size and depth of an abdominal wound? Never.

Now there is a better “mousetrap” that that fits our needs: the SNaP® (Spiracur). With this product, I believe wounds we have been depriving of negative pressure wound therapy (NPWT) will no longer be left wanting.

I and my colleagues, first at the University of Texas Health Science Center at San Antonio and now at the Western University College of Podiatric Medicine in Southern California, have shied away from using NPWT on wounds like the diabetic ulcer under a metatarsal head or at the tip of a digit, the ulceration over a bunion deformity or a small puncture wound site.

Such wounds are too small, we would argue, for such a big gun treatment. The treatment is not cost effective, we might say, for the size of the wound unless it became problematic and we had to open it up more extensively due to non-healing down the line.

What The Recent Literature Reveals

It is reassuring to read that prominent researcher David Armstrong, DPM, MD, PhD, and leading clinicians are agreeing with me on this. Armstrong and colleagues tested the SNaP system in a 12-center randomized, controlled trial of 65 patients with non-infected, non-ischemic, dorsal lower extremity wounds.1 The preliminary results of the study showed that the SNaP device had no difference in wound closure rates in a head-to-head comparison with VAC therapy.

In the latest publication in Ostomy Wound Management, Nemes and Robertson showed the SNaP’s efficacy on exactly the type of wound I am talking about: the distal tip of the hallux in a patient with diabetes.2 The ulcer had been present for nine months. After the clinicians debrided the underlying osteomyelitis and treated the infection, the patient underwent SNaP treatment for the 8 mm x 9 mm x 20 mm ulcer (length x width x depth).

At four weeks, the ulceration was small enough that the clinicians chose to place Apligraf (Organogenesis) and Mepitel (Molnlycke) non-adherent dressing on the previous ulcer site. 2 Frankly, I would not have used an Apligraf because at that point, the wound seemed to have epithelialized well enough to me. (For photos of the wound, see ). Suffice it to say, the wound is pinpoint at that stage.

The clinicians do report that it took about 58 minutes to apply the device the first time. However, they note that this decreased to seven minutes (with a range of three to 10 minutes) as their familiarity with the device grew.

Other Considerations With The SNaP System

Another key difference between VAC therapy and the SNaP system is that the SNaP is a modality that the clinician orders in bulk, keeps on the shelf in the office and then dispenses.

Spiracur is still working to get an outpatient code and this would likely lead to a significant increase in use for our patients. Right now for insurance purposes, the SNaP is limited to hospital use. Otherwise, it is available for cash paying patients in all settings. The cost to DPMs in the profession is roughly 20 to 30 percent less than for the VAC therapy system.

This SNaP system requires no power source. It needs no electricity or batteries. You throw it away into a biohazard bag after you are done with it. This is an ingenious invention. There is no noise (a big deal for some patients) but it still offers NPWT at 75, 100 and 125 mmHg through suction.

Patients are going to love this. It is small and it does not weigh a lot. It does not require canister changes. You change the unit as a whole — all 3 oz. of it. The patient does not have to be hooked up to a power source or to batteries. As a former wound patient, these attributes are a very big deal.

If you can get healing for smaller, more awkwardly sized wounds, why not consider the SNaP system? In my view, this is indeed a better wound care “mousetrap.”

There will be plenty of wounds for VAC therapy to conquer still. I just recommended VAC therapy for a colleague’s patient yesterday. The patient had a gaping Loeffler-Ballard incision for a previous diabetic foot infection that exposed all of the plantar muscle compartments. That is a VAC therapy wound, not a SNaP wound.

However, I would venture to say that most podiatrists see ulcers and wounds in their day-to-day practice that are smaller than that but are usually more difficult to heal than the acute or traumatic wound.

If the wound is 15 x 15 cm (the size of the dressing) or smaller and if it is exudating less than 100 cc a week, then the hospital and patient will appreciate that you will save them money for the same outcome. I was interested in the fact that the SNaP system requires only two — versus the VAC therapy’s three — dressing changes per week.

Final Notes

I challenge each one of us to build the better mousetrap for podiatry. I see a huge need in several other areas that we treat. I will blog more about those in the near future. I welcome your suggestions about areas where you believe we need innovation or new products that you think have provided us with that “better mousetrap” for our patients. Please share your thoughts and suggestions with all of us.

Editor’s note: Dr. Satterfield discloses that she is not a speaker or paid consultant for Spiracur.


1. Armstrong DG, Marston WA, Reyzelman AM, Kirsner RS. Comparison of negative pressure wound therapy with an ultraportable mechanically powered device vs. traditional electrically powered device for the treatment of chronic lower extremity ulcers: a multicenter randomized-controlled trial. Wound Repair Regen. 2011; 19(2):173-80.

2. Nemes K, Robertson R. Treatment of a diabetic hallux ulcer with ultraportable negative pressure wound therapy: a case study. Ostomy Wound Manage. . Published April 12, 2011. Accessed April 26, 2011.


Thanks for the heads-up, Kathy. That one hasn't made it to our area yet.

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