SOCIETY FOR VASCULAR SURGERY WOUND, ISCHEMIA AND FOOT INFECTION (WIFI) CLASSIFICATION SYSTEM: CHARACTERIZATION OF WOUNDS SISTEMA DE CLASSIFICAÇÃO DA SOCIEDADE DE CIRURGIA VASCULAR WOUND, ISCHEMIA, FOOT INFECTION (WIfI): CARACTERIZAÇÃO DAS FERIDAS

Objective: To identify the characteristics and severity of wounds in studies with classification of the WIfI System (Wound; Ischemia; foot Infection). Method: This is an integrative literature review, of a descriptive nature. Searches were performed at the MEDLINE and Virtual Health Library (VHL) databases, using the descriptors in English: “wound healing”, “amputation”, “diabetic foot” and “peripheral vascular disease”. The search identified 54 publications, and, after analysis and application of inclusion and exclusion criteria, 12 articles remained. Results: There was a predominance of studies with level of evidence 2B according to the Oxford Center Classification for Evidence-Based Medicine. Regarding the patients’ profile, those with peripheral arterial disease who underwent limb revascularization predominated. A complex wound profile was found, medium to large in size, with little possibility of healing without a multidisciplinary action. Conclusion: The research showed that the main characteristics about the wounds presented in studies using the classification of the WIfI System (Wound; Ischemia; foot Infection) were wounds with bone exposure and extensive wounds. Thus, nursing professionals, as members of the multidisciplinary team, should know the WIfI classification, in order to be able to identify and refer a patient with ischemia for revascularization earlier.


INTRODUCTION
Diabetes is a worldwide public health problem. According to the authors (1) , the main complication of diabetes is diabetic foot, which is "one of the most serious complications", with high costs for health institutions and worsening the patient's quality of life (1) .
Authors' studies (2) "about 15% of patients with diabetes will develop an ulcer". This is one of the main complications of diabetes, with high costs for health services.
The presence of foot ulcers in diabetic patients leads to an increase in mortality (2) , The authors (3) also add that diabetic foot ulcer is one of the main causes of hospital admissions and amputation. However, studies indicate that 25% of ulcers do not have a prospect of healing (4) . Another unfavorable outcome for diabetic foot ulcer stems from lower limbs, and every year 1 million people with diabetes are amputated, which means that every 20 seconds a person has a limb amputated due to diabetes (4) . In view of its systemic involvement, affecting the macrovasculature and microvasculature part (5) , its association with peripheral arterial disease, it can further increase amputation and mortality rates.
The main causative factor of peripheral arterial disease (PAD) is atherosclerosis, which has been described as a common pathology, with a prevalence of up to 10% in people aged under 70 years and up to 20% in the world population above this age.
In this context, the present work aims to identify the main characteristics and severity of wounds presented in studies using the classification of the WIfI System (Wound; Ischemia; foot Infection).

METHOD
This is an integrative review. This type of study is the "methodological approach

RESULTS
The saerch for the articles through Medline, this being a tool to search for scientific articles in the health area, using the  (2019).

DISCUSSION
The main characteristics of wounds presented in studies using the WIfI classification system (Wound; Ischemia; foot Infection) were grade 2 wounds of the lesions located in the forefoot, affecting two or more digits and/or superficial ulcers in the heel, with or without bone and tendon exposure.
However, some studies presented grade 2 and 3 wounds, representing a greater severity in relation to the extent and depth of the wounds, subjecting the patient to high risks for major amputation.
In view of the concern of the high rates of non-traumatic amputation and mortality, several strategies and tools are needed to assist the professional and the team in the search for alternatives that accelerate decision-making and early therapy. The wound has been an important factor for amputation risk, being evaluated together with two other factors of equal importance, i.e., ischemia and infection. Previously, ischemia was the only characteristic considered as a risk factor for major amputation, which is described as amputations above the ankle (transtibial, knee disarticulation, transfemoral or hip disarticulation) (24) (26) add that wound size is an important factor for successful healing. The authors (27) described that the wound area increased as the days (27) . Cull et al (2014) (12) report a healing rate of 79%, identifying mostly wounds with grade 2 and 3, demonstrating severity and great extent of these wounds, requiring several multidisciplinary interventions to achieve those healing rates, also described as a factor that interferes in the healing of diabetes, wound size and depth and location According to a study (28) , patients present negative perception with rejection of their own image, also reporting that they believe that other people also see them negatively, generating important emotional and psychological conflicts to them (28) . Driver et al (29) report that the costs of treating wounds with a higher degree increase by up to eight times the value in relation to lower-grade wounds (29) .
The authors (17) state that the wound healing rate reduced as the stages of the WIfI classification increased, thus the higher the severity of the wound, the lower the chances of wound healing (17) . These factors described in the study (12) demonstrate that nurses' role with preventive measures such as guidance with health education, and early identification of wounds can facilitate healing. After healing, follow-up is necessary to avoid recurrences, through health education, a strategy that can avoid up to 75% of recurrent wounds (30) .
The identification of the wound and its degree of complexity is necessary to the nurse, as this professional performs the dressings and usually defines the therapies for topical treatment. The authors (31) affirm the importance of nurses in assuming responsibility in "maintaining observation in relation to local, systemic and external factors that condition the appearance of the wound or interfere in the healing process" (31) . Thus, knowing and applying the WIfI classification as a system of clinical decision support by nurses is valid (32) for this resumption of actions and responsibility regarding the treatment of patients with wounds, enabling improvements in the quality of life of the patient and reduction of costs with the treatment of wounds. Another important action of the nurse regarding the degree of wounds is to be attentive to health education, because it contributes to self-care and prevention of new complications (33) .

CONCLUSION
The present   2018.