I'm interested in taking the CWCA exam, but a friend of mine mentioned that the WCC is better. What is the difference between the two?
Noncontact Normothermic Wound Therapy and Offloading in the Treatment of Neuropathic Foot Ulcers in Patients with Diabetes
- Wed, 9/3/08 - 10:24am
- 0 Comments
- 5593 reads
A n estimated 5% to 6% of the population of the United States has diabetes.1 A common complication of the disease is plantar ulceration secondary to sensory neuropathy and the repetitive stress of walking.2 Nonhealing foot ulcerations secondary to diabetes have been implicated in up to 90% of all amputations in Japan, Taiwan, Spain, Italy, Canada, the United States, and England.3-5 Half of all nontraumatic lower extremity amputations reported in the United States occur in people with diabetes; minorities account for a disproportionately high number of these cases.6
If clinicians are to have an impact on the diabetic population, attention must be directed to preventing ulceration or, in cases where ulceration is already present, to facilitating wound healing. In addition, glucose must be properly controlled and other factors such as adequate blood supply and pressure reduction in the lower extremities must be addressed.
Although blood supply may be adequate to support the basal needs of intact tissue in people with diabetes, the increased oxygen demands for healing are quite different.7 Without adequate blood flow and oxygenation, tissue infection rates rise and amputations become more likely. Because vascular supply to wounds is often compromised, a hypoxic state frequently exists. This, in turn, correlates with decreased tissue temperature. Typically, hypoxic wounds have temperatures between 26o to 33oC8-10; therefore, heat may be one of the most effective means of increasing oxygen perfusion in tissues and, subsequently, reducing infection.11,12
Van Hoft's law states that for every 10o-C rise in tissue temperature, a two- to threefold increase in cellular metabolism occurs.13 Excessive heat is detrimental, as thermal burns can result. The challenge is to find a safe means of providing controlled, mild warming of hypothermic tissues.
A relatively new device has been developed to deliver gentle warmth to wounds via a noncontact, semiocclusive dressing. The device, termed Warm-Up wound therapy® (Augustine Medical, Inc., Eden Prairie, Minn.), delivers humidified warmth to the wound and periwound skin at a normothermic temperature of 38oC ± 1oC. Recently published controlled clinical trials14,15 and case reports16,17 support the effectiveness of this device in accelerating healing in patients with pressure and venous insufficiency ulcers.
In addition to circulation, another factor that must be addressed when managing patients with diabetic foot ulcerations is offloading the extremity. If high plantar pressures persist, foot wounds will not heal.18 A variety of mechanisms have proven useful in decreasing plantar foot pressures. The present day gold standard is the total contact walking cast (TCC), first introduced in the United States in 1965.2 The TCC is designed to shift high pressures from wounds and bony prominences by distributing weightbearing forces over as large an area as possible. However, total contact walking casts are not always feasible when daily wound care is required. In such cases, custom fabricated posterior walking splints or halfshoes with metatarsal bars are often preferred.18
Because most noninfected, neuropathic foot ulcers heal when pressure is removed from the wound, the authors sought to determine if the healing rate could be accelerated by adding controlled warmth. A randomized, controlled clinical trial was undertaken to address this question.
References:
1. Foundation for Accountability. Measuring health care quality: Diabetes. Rockville, MD: Agency for Health Care Policy and Research; 1996.
2. Birke J, Patout C. The contact cast: an update and case study report. Wounds. 2000;12:26-31.
3. Mulder G. Evaluating and measuring the diabetic foot: an overview. Advances in Skin and Wound Care. 2000;12:33-39.
4. Pecoraro R, Reiber G, Burgess E. Pathways to diabetic limb amputation: basis for prevention. Diabetes Care. 1990;13:513-521.
5. Group TG. The Global Lower Extremity Amputation Study Group. Epidemiology of lower extremity amputation in centres in Europe, North America and East Asia. B J Surg. 2000;87:328-337.
6. Harris M, Cowie C, Stern M, et al. Diabetes in America. In: Reiber G, Boyko E, Smith D, eds. Lower Extremity Foot Ulcers and Amputation in Diabetes, 2nd ed. Washington, DC: US Govt Printing Office; 1995.
7. Bowker J. A holistic approach to foot wound healing in diabetic persons with and without dysvascularity. Wounds. 2000;12:72B-76B.
8. West J, Hopf H, Hunt T. A radiant-heat bandage increases abdominal subcutaneous oxygen tension and temperature. Wound Repair and Regeneration. 1996;4:A134.
9. Ikeda T, Tayefeh F, Sessler D, et al . Local radiant heating increases subcutaneous oxygen tension. Am J Surg. 1998;175:33-37.
10. Ikeda t, Kurz A, Tayefeh F, Plattner DSO, Hopf H. The effect of three different local heating temperatures on subcutaneous oxygen tension. Anesth Analg. 1997;84.
11. Rabkin J, Hunt T. Local heat increases blood flow and oxygen tension in wounds. Arch Surg. 1987;122:221-225.
12. Kurz A, Sessler D, Lenhardt R. Perioperative normothermia to reduce the incidence of surgical wound infection and shorten hospitalization. N Engl J Med. 1996;334:1209-1215.
13. Fischer E, Soloman S. Physiological responses to heat and cold. In: Licht S, ed. Therapeutic Heat and Cold. Baltimore, Md.: Waverly Press; 1965:127-128.
14. Kloth L, Berman J, Dumit-Minkel S, Sutton C, Papanek P, Wurzel J. Effects of a normothermic dressing on pressure ulcer healing. Advances in Skin and Wound Care. 2000;46:69-74.
15. Robinson C, Santilli S. Warm-Up active wound therapy: a novel approach to the management of chronic venous stasis ulcers. Journal of Vascular Nursing. 1998;26:38-42.
16. Santilli S, Valusek P, Robinson C. Use of a noncontact radiant heat bandage for the treatment of chronic venous stasis ulcers. Advances in Wound Care. 1999;12:89-93.
17. Cherry G, Wilson J. The treatment of ambulatory venous ulcer patients with warming therapy. Ostomy/Wound Management. 1999;45:65-70.
18. Armstrong D, Lavery L, Harkless L. Options for offloading the diabetic foot. Wounds. 2000;12:30B-34B.
19. Gilman T, Margolis D. Comparing healing rates across studies is the vision, but first, a correct equation please! Ostomy/Wound Management. 1995;41:6-7.
20. Boulton A, Meneses P, Ennis W. Diabetic foot ulcers: a framework for prevention and care. Wound Repair and Regeneration. 1999;7:7-16.
21. Margolis D, Kantor J, Berlin J. Healing of diabetic neuropathic foot ulcers receiving standard treatment: a meta analysis. Diabetes Care. 1999;22(5):692-695.
22. Kantor J, Margolis D. Expected healing rates in chronic wounds. Wounds. 2000;12:155-158.
23. Armstrong D, Lavery L, Bushman T. Peak foot pressures influence the healing time of diabetic foot ulcers treated with total contact casts. J Rehabil Res Dev. 1998;35:1-5.
24. Inlow S, Orsted H, Sibbald RG. Best practice for the prevention, diagnosis and treatment of diabetic foot ulcers. OstomyWound Management. 2000; 46:55-68.
_sm.jpg)
Post new comment